Assessment of Appalachian basin oil and gas resources: Devonian gas shales of the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System: Chapter G.9 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Milici, Robert C.; Swezey, Christopher S.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

This report presents the results of a U.S. Geological Survey (USGS) assessment of the technically recoverable undiscovered natural gas resources in Devonian shale in the Appalachian Basin Petroleum Province of the eastern United States. These results are part of the USGS assessment in 2002 of the technically recoverable undiscovered oil and gas resources of the province. This report does not use the results of a 2011 USGS assessment of the Devonian Marcellus Shale because the area considered in the 2011 assessment is much greater than the area of the Marcellus Shale described in this report. The USGS assessment in 2002 was based on the identification of six total petroleum systems, which include strata that range in age from Cambrian to Pennsylvanian. The Devonian gas shales described in this report are within the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System, which extends generally from New York to Tennessee. This total petroleum system is divided into ten assessment units (plays), four of which are classified as conventional and six as continuous. The Devonian shales described in this report make up four of these continuous assessment units. The assessment results are reported as fully risked fractiles (F95, F50, F5, and the mean); the fractiles indicate the probability of recovery of the assessment amount. The products reported are oil, gas, and natural gas liquids. The mean estimates for technically recoverable undiscovered hydrocarbons in the four gas shale assessment units are 12,195.53 billion cubic feet (12.20 trillion cubic feet) of gas and 158.91 million barrels of natural gas liquids

Mineral resources of the Little Black Peak and Carrizozo Lava Flow wilderness study areas, Lincoln County, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoeser, D.B.; Senterfit, M.K.; Zelten, J.E.

1989-01-01

This book discusses the Little Black Peak and Carrizozo Lava Flow Wilderness Study Areas in east-central New Mexico (24,249 acres) which are underlain by Quaternary basaltic lava flows and upper Paleozoic to Mesozoic sedimentary rocks. The only identified resource is lava from the basalt flows, which is used for road metal, construction materials, and decorative stone. The basalt is classed as an inferred subeconomic resource. Both areas have low resource potential for sediment-hosted uranium and copper oil, gas, coal, and geothermal energy and moderate potential for gypsum and salt. The Little Black Peak area also has low potential for uraniummore » associated with Tertiary alkaline intrusive rocks. Two aeromagnetic anomalies occur beneath the northern part of the Carrizozo lava flow area and the southern part of the Little Black Peak area; the resource potential for these rocks is unknown.« less

A new reconstruction of the Paleozoic continental margin of southwestern North America: Implications for the nature and timing of continental truncation and the possible role of the Mojave-Sonora megashear

USGS Publications Warehouse

Stevens, C.H.; Stone, P.; Miller, J.S.

2005-01-01

Data bearing on interpretations of the Paleozoic and Mesozoic paleogeography of southwestern North America are important for testing the hypothesis that the Paleozoic miogeocline in this region has been tectonically truncated, and if so, for ascertaining the time of the event and the possible role of the Mojave-Sonora megashear. Here, we present an analysis of existing and new data permitting reconstruction of the Paleozoic continental margin of southwestern North America. Significant new and recent information incorporated into this reconstruction includes (1) spatial distribution of Middle to Upper Devonian continental-margin facies belts, (2) positions of other paleogeographically significant sedimentary boundaries on the Paleozoic continental shelf, (3) distribution of Upper Permian through Upper Triassic plutonic rocks, and (4) evidence that the southern Sierra Nevada and western Mojave Desert are underlain by continental crust. After restoring the geology of western Nevada and California along known and inferred strike-slip faults, we find that the Devonian facies belts and pre-Pennsylvanian sedimentary boundaries define an arcuate, generally south-trending continental margin that appears to be truncated on the southwest. A Pennsylvanian basin, a Permian coral belt, and a belt of Upper Permian to Upper Triassic plutons stretching from Sonora, Mexico, into westernmost central Nevada, cut across the older facies belts, suggesting that truncation of the continental margin occurred in the Pennsylvanian. We postulate that the main truncating structure was a left-lateral transform fault zone that extended from the Mojave-Sonora megashear in northwestern Mexico to the Foothills Suture in California. The Caborca block of northwestern Mexico, where Devonian facies belts and pre-Pennsylvanian sedimentary boundaries like those in California have been identified, is interpreted to represent a missing fragment of the continental margin that underwent ???400 km of left-lateral displacement along this fault zone. If this model is correct, the Mojave-Sonora megashear played a direct role in the Pennsylvanian truncation of the continental margin, and any younger displacement on this fault has been relatively small. ?? 2005 Geological Society of America.

Selenium in Paleozoic stone coal (carbonaceous shale) as a significant source of environmental contamination in rural southern China

NASA Astrophysics Data System (ADS)

Belkin, H. E.; Luo, K.

2012-04-01

Selenium occurs in high concentrations (typically > 10 and up to 700 ppm) in organic-rich Paleozoic shales and cherts (called "stone coal" - shíméi), in southern China. Stone coals are black shales that formed in anoxic to euxinic environments and typically contain high concentrations of organic carbon, are enriched in various metals such as V, Mo, Pb, As, Cr, Ni, Se, etc., and are distinguished from "humic" coal in the Chinese literature. We have examined stone coal from Shaanxi, Hubei, and Guizhou Provinces, People's Republic of China and have focused our study on the mode of occurrence of Se and other elements (e.g. As, Pb, etc.) hazardous to human health. Scanning electron microscope, energy-dispersive analysis and electron microprobe wave-length dispersive spectroscopy were used to identify and determine the composition of host phases observed in the stone coals. Native selenium, Se-bearing pyrite and other sulfides are the hosts for Se, although we cannot preclude an organic or clay-mineral association. Stone coals are an important source of fuel (reserves over 1 billion tonnes), both domestically and in small industry, in some rural parts of southern China and present significant environmental problems for the indigenous population. The stone coals create three main environmental problems related to Se pollution. First, the residual soils formed on stone coal are enriched in Se and other metals contained in the stone coals and, depending on the speciation and bioavailability of the metals, may enrich crops and vegetation grown on them. Second, weathering and leaching of the stone coal contaminates the local ground water and/or surface waters with Se and other metals. Third, the local population uses the stone coal as a source of fuel, which releases the more volatile elements (Se and As) into the atmosphere in the homes. The ash will be extremely enriched with the balance of the heavy metal suite. Disposal of the ash on agricultural lands or near water supplies will contaminate both. Human and animal selenosis has been observed in economically and geographically isolated rural communities in areas underlain by stone coal. However, local Public Health officials have adequately dealt with these cases of local selenium poisoning. In Enshi, Hubei Province, Se-contaminated farmland has been replanted with tea and the Se-enriched tea has been marketed nationally.

Morphology and systematics of cordaites of Pennsylvanian coal swamps of Euramerica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Costanza, S.H.

1984-01-01

Cordaites are extinct coniferophytic shrubs and trees of the Late Paleozoic. They were most prominent in tropical coal swamps existing from the Westphalian A-B boundary of Western Europe to the middle Desmoinesian (Westphalian D) of midcontinental United States. Structurally preserved coal-ball cordaites from Pennsylvanian Euramerican coals were analyzed for whole plant understanding, morphological variation, and indications of ecological tolerances. Organ assemblages for individual species were established from coals where coal balls contain single cordaitean seed species. Cordaitean organ assemblages were stratigraphically compiled, compared, and cross-correlated. Cordaitean assemblage comparisons of most known coals with coal balls confirm organ assemblages established formore » Pennsylvanioxylon, and indicate that Mesoxylon bore Mitrospermum ovules. Mesoxylon and Pennsylvanioxylon are the only coal-swamp Pennsylvanian cordaitean genera recognized herein. They are consistently different in stem xylem development, leaf and branch trace formation, in amount of cortical sclerenchyma and associated organs. Morphology of coal-swamp cordaites, especially cortical aerenchyma in Pennsylvanioxylon, indicates semi-aquatic ecological adaptation. Coal-swamp cordaitean lineages may demonstrate both gradualistic and punctuational evolutionary changes.« less

Total Petroleum Systems of the North Carpathian Province of Poland, Ukraine, Czech Republic, and Austria

USGS Publications Warehouse

Pawlewicz, Mark

2006-01-01

Three total petroleum systems were identified in the North Carpathian Province (4047) that includes parts of Poland, Ukraine, Austria, and the Czech Republic. They are the Isotopically Light Gas Total Petroleum System, the Mesozoic-Paleogene Composite Total Petroleum System, and the Paleozoic Composite Total Petroleum System. The Foreland Basin Assessment Unit of the Isotopically Light Gas Total Petroleum System is wholly contained within the shallow sedimentary rocks of Neogene molasse in the Carpathian foredeep. The biogenic gas is generated locally as the result of bacterial activity on dispersed organic matter. Migration is also believed to be local, and gas is believed to be trapped in shallow stratigraphic traps. The Mesozoic-Paleogene Composite Total Petroleum System, which includes the Deformed Belt Assessment Unit, is structurally complex, and source rocks, reservoirs, and seals are juxtaposed in such a way that a single stratigraphic section is insufficient to describe the geology. The Menilite Shale, an organic-rich rock widespread throughout the Carpathian region, is the main hydrocarbon source rock. Other Jurassic to Cretaceous formations also contribute to oil and gas in the overthrust zone in Poland and Ukraine but in smaller amounts, because those formations are more localized than the Menilite Shale. The Paleozoic Composite Total Petroleum System is defined on the basis of the suspected source rock for two oil or gas fields in western Poland. The Paleozoic Reservoirs Assessment Unit encompasses Devonian organic-rich shale believed to be a source of deep gas within the total petroleum system. East of this field is a Paleozoic oil accumulation whose source is uncertain; however, it possesses geochemical similarities to oil generated by Upper Carboniferous coals. The undiscovered resources in the North Carpathian Province are, at the mean, 4.61 trillion cubic feet of gas and 359 million barrels of oil. Many favorable parts of the province have been extensively explored for oil and gas. The lateral and vertical variability of the structure, the distribution and complex geologic nature of source rocks, and the depths of potential exploration targets, as well as the high degree of exploration, all indicate that future discoveries in this province are likely to be numerous but in small fields.

North American Paleozoic land snails with a summary of other Paleozoic nonmarine snails

USGS Publications Warehouse

Solem, Alan; Yochelson, Ellis Leon

1979-01-01

Land snails from the Paleozoic of North America are known from the coal fields of eastern Canada, from the Dunkard basin west of the Allegheny Mountains, and from the western margin of the Illinois basin. The earliest finds were made about 125 years ago; essentially no new information has been recorded for a century. Large collections of Anthracopupa from the Dunkard basin sparked inquiry into the land snails from the other two areas. Studies using the SEM (scanning electron microscope) have provided considerable insight into microdetails of shell structure, which allow systematic assignment of these gastropods. All may be assigned to extant families, except one, for which insufficient material allows only superfamily assignment. The prosobranch Dawsonella is confirmed as being a terrestrial neritacean gastropod. To date, it is known only from the upper Middle Pennsylvanian of Illinois and Indiana. All the other Paleozoic land snails are stylommatophoran pulmonates; their current classification as nonmarine cyclophoraceans is not correct. Restudy of material from the Joggins section of Nova Scotia indicates that representatives of two ordinal groups of pulmonates appeared simultaneously in upper Lower Pennsylvanian strata; the oldest land prosobranch is found in only very slightly younger rocks. Zonites (Conulus) priscus is reassigned to the new genus Protodiscus in the extant family Discidae. Dendropupa is placed within the family Enidae, Anthraaopupa is placed in the family Tornatellinidae, and 'Pupa' bigsbii is assigned to the superfamily Pupillacea. All four of these family-level taxa are diverse and belong to two orders within the superorder Stylommatophora, heretofore considered a derived rather than an ancestral stock. Anthracopupa ohioensis Whitfield is a highly variable species, and two other species Naticopsis (?) diminuta and A.(?) dunkardona, both named by Stauffer and Schroyer, are placed in synonymy with it. To obtain taxonomic data to support the family placement of Anthracopupa, growth forms of modern pupillid and tornatellinid snails have been distinguished. The apertural barriers in Anthracopupa are identical in placement and growth pattern with those of living Tornatellinidae and independently confirm the family placement derived from study of the general form. One new species, A. sturgeoni, has been named. Anthracopupa is found most commonly in thin limestones interpreted as having been deposited in pools into which the small shells floated. Dendropupa is most commonly found in erect tree stumps that were covered by rapid sedimentation. Both environments are similar to those in which the shells of allied living species may be found today, and the fossils support environmental interpretations made entirely from lithology. A survey of the few European occurrences of Paleozoic land snails indicates that both Anthracopupa and Dendropupa occur in Lower Permian strata; Anthracopupa is known from beds as old as Westphalian B. These genera cannot be used for determining the Carboniferous-Permian boundary. Both the long local stratigraphic range of A. brittanica and D. vetusta reported in the literature and the moderately long range and great variability of A. ohioensis suggest that the land snails have little stratigraphic utility. On the other hand, the occurrence of these land snails in the late Paleozoic of the Northern Hemisphere provides further fossil evidence suggestive of a closed Atlantic Ocean at that time. A comparison of the Paleozoic and the present distributions of land -snail families on both sides of the Atlantic provides some interesting data on geographic shifts of organisms. Finally, the assignment of the earliest land snails to extant taxa at the family level indicates that the subclass Pulmonata has been very conservative in its evolution after initial radiation. A few notes on Paleozoic freshwater snails complete this survey.

Shahejie-Shahejie/Guantao/Wumishan and Carboniferous/Permian Coal-Paleozoic Total Petroleum Systems in the Bohaiwan Basin, China (based on geologic studies for the 2000 World Energy Assessment Project of the U.S. Geological Survey)

USGS Publications Warehouse

Ryder, Robert T.; Qiang, Jin; McCabe, Peter J.; Nuccio, Vito F.; Persits, Felix

2012-01-01

This report discusses the geologic framework and petroleum geology used to assess undiscovered petroleum resources in the Bohaiwan basin province for the 2000 World Energy Assessment Project of the U.S. Geological Survey. The Bohaiwan basin in northeastern China is the largest petroleum-producing region in China. Two total petroleum systems have been identified in the basin. The first, the Shahejie&ndashShahejie/Guantao/Wumishan Total Petroleum System, involves oil and gas generated from mature pods of lacustrine source rock that are associated with six major rift-controlled subbasins. Two assessment units are defined in this total petroleum system: (1) a Tertiary lacustrine assessment unit consisting of sandstone reservoirs interbedded with lacustrine shale source rocks, and (2) a pre-Tertiary buried hills assessment unit consisting of carbonate reservoirs that are overlain unconformably by Tertiary lacustrine shale source rocks. The second total petroleum system identified in the Bohaiwan basin is the Carboniferous/Permian Coal–Paleozoic Total Petroleum System, a hypothetical total petroleum system involving natural gas generated from multiple pods of thermally mature coal beds. Low-permeability Permian sandstones and possibly Carboniferous coal beds are the reservoir rocks. Most of the natural gas is inferred to be trapped in continuous accumulations near the center of the subbasins. This total petroleum system is largely unexplored and has good potential for undiscovered gas accumulations. One assessment unit, coal-sourced gas, is defined in this total petroleum system.

Appalachian coal assessment: Defining the coal systems of the Appalachian basin

USGS Publications Warehouse

Milici, R.C.

2005-01-01

The coal systems concept may be used to organize the geologic data for a relatively large, complex area, such as the Appalachian basin, in order to facilitate coal assessments in the area. The concept is especially valuable in subjective assessments of future coal production, which would require a detailed understanding of the coal geology and coal chemistry of the region. In addition, subjective assessments of future coal production would be enhanced by a geographical information system that contains the geologic and geochemical data commonly prepared for conventional coal assessments. Coal systems are generally defined as one or more coal beds or groups of coal beds that have had the same or similar genetic history from their inception as peat deposits, through their burial, diagenesis, and epigenesis to their ultimate preservation as lignite, bituminous coal, or anthracite. The central and northern parts of the Appalachian basin contain seven coal systems (Coal Systems A-G). These systems may be defined generally on the following criteria: (1) on the primary characteristics of their paleopeat deposits, (2) on the stratigraphic framework of the Paleozoic coal measures, (3) on the relative abundance of coal beds within the major stratigraphic groupings, (4) on the amount of sulfur related to the geologic and climatic conditions under which paleopeat deposits accumulated, and (5) on the rank of the coal (lignite to anthracite). ??2005 Geological Society of America.

Biostratigraphy and petrography of upper Paleozoic rocks of Sierra Las Pintas, northern Baja California

NASA Astrophysics Data System (ADS)

Navas-Parejo, Pilar; Lara-Peña, R. Aaron; Torres-Martínez, Miguel Angel; Martini, Michelangelo

2018-07-01

A transported crinoid fauna is herein described for the first time in the Paleozoic succession cropping out in the Sierra Las Pintas, northern Baja California, northwestern Mexico. The fossil association includes Heterostelechus texanus Moore and Jeffords, Preptopremnum laeve? Moore and Jeffords, and Mooreanteris perforatus Moore and Jeffords, which indicates a Middle Pennsylvanian-early Permian time-averaged age. The studied area corresponds with the northernmost outcrop of definitely late Paleozoic deep-water facies in northwestern Mexico and the southern United States. Petrographic analyses indicate that the studied metasandstones were primarily derived from high-grade metamorphic rocks and from a shallow-water platform environment dominated by crinoid meadows. These results allow the correlation of the studied metasedimentary rocks with the Carboniferous Rancho Nuevo Formation of the Sonora allochthon, which crops out in central Sonora. The Sonora allochthon includes an Early Ordovician-Late Pennsylvanian sedimentary succession that was deposited in the oceanic basin located south of the Laurentian craton. Therefore, upper Paleozoic metasedimentary rocks of the Sierra Las Pintas were deposited along the same continental margin of Laurentia as those rocks in the Sonora allochthon, and were mostly derived from metamorphic rocks of the continental craton and by the typical Carboniferous encrinites, which characterize the shallow-water rocks of central and northern Sonora.

Hydrologic properties and ground-water flow systems of the Paleozoic rocks in the upper Colorado River basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, excluding the San Juan Basin

USGS Publications Warehouse

Geldon, Arthur L.

2003-01-01

The hydrologic properties and ground-water flow systems of Paleozoic sedimentary rocks in the Upper Colorado River Basin were investigated under the Regional Aquifer-System Analysis (RASA) program of the U.S. Geological Survey in anticipation of the development of water supplies from bedrock aquifers to fulfill the region's growing water demands. The study area, in parts of Arizona, Colorado, New Mexico, Utah, and Wyoming, covers about 100,000 square miles. It includes parts of four physiographic provinces--the Middle Rocky Mountains, Wyoming Basin, Southern Rocky Mountains, and Colorado Plateaus. A variety of landforms, including mountains, plateaus, mesas, cuestas, plains, badlands, and canyons, are present. Altitudes range from 3,100 to 14,500 feet. Precipitation is distributed orographically and ranges from less than 6 inches per year at lower altitudes to more than 60 inches per year in some mountainous areas. Most of the infrequent precipitation at altitudes of less than 6,000 feet is consumed by evapotranspiration. The Colorado and Green Rivers are the principal streams: the 1964-82 average discharge of the Colorado River where it leaves the Upper Colorado River Basin is 12,170 cubic feet per second (a decrease of 5,680 cubic feet per second since construction of Glen Canyon Dam in 1963). On the basis of their predominant lithologic and hydrologic properties, the Paleozoic rocks are classified into four aquifers and three confining units. The Flathead aquifer, Gros Ventre confining unit, Bighorn aquifer, Elbert-Parting confining unit, and Madison aquifer (Redwall-Leadville and Darwin-Humbug zones) make up the Four Corners aquifer system. A thick sequence, composed mostly of Mississippian and Pennsylvanian shale, anhydrite, halite, and carbonate rocks--the Four Corners confining unit (Belden-Molas and Paradox-Eagle Valley subunits)--overlies the Four Corners aquifer system in most areas and inhibits vertical ground-water flow between the Four Corners aquifer system and the overlying Canyonlands aquifer. Composed of the uppermost Paleozoic rocks, the Canyonlands aquifer consists, in ascending order, of the Cutler-Maroon, Weber-De Chelly, and Park City-State Bridge zones. The Paleozoic rocks are underlain by a basal confining unit consisting of Precambrian sedimentary, igneous, and metamorphic rocks and overlain throughout most of the Upper Colorado River Basin by the Chinle-Moenkopi confining unit, which consists of Triassic formations composed mostly of shale. The largest values of porosity, permeability, hydraulic conductivity, transmissivity, and artesian yield are exhibited by the Redwall-Leadville zone of the Madison aquifer and the Weber-De Chelly zone of the Canyonlands aquifer. The former consists almost entirely of Devonian and Mississippian carbonate rocks: the latter consists mostly of Pennsylvanian and Permian quartz sandstone. Unit-averaged porosity in hydrogeologic units composed of Paleozoic rocks ranges from less than 1 to 28 percent. Permeability ranges from less than 0.0001 to 3,460 millidarcies. Unit-averaged hydraulic conductivity ranges from 0.000005 to 200 feet per day. The composite transmissivity of Paleozoic rocks ranges from 0.0005 to 47,000 feet squared per day. Artesian yields to wells and springs (excluding atypical springflows) from these hydrogeologic units range from less than 1 to 10,000 gallons per minute. The permeability and watersupply capabilities of all hydrogeologic units progressively decrease from uplifted areas to structural basins. Recharge to the Paleozoic rocks is provided by direct infiltration of precipitation, leakage from streams, and ground-water inflows from structurally continuous areas west and north of the Upper Colorado River Basin. The total recharge available flom ground-water systems in the basin from direct precipitation and stream leakage is estimated to be 6,600,000 acre-feet per year. However, little of this recharge directly enters the Paleozoic rocks

Results of coalbed-methane drilling, Mylan Park, Monongalia County, West Virginia: Chapter G.3 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Ruppert, Leslie F.; Fedorko, Nick; Warwick, Peter D.; Grady, William C.; Britton, James Q.; Schuller, William A.; Crangle, Robert D.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

High-pressure carbon-dioxide adsorption isotherms were measured on composite coal samples of the Upper Kittanning coal bed and the Middle Kittanning and Clarion coal zones. Assuming that the reservoir pressure in the Mylan Park coals is equivalent to the normal hydrostatic pressure, the estimated maximum carbon-dioxide adsorption pressures range from a low of about 300 pounds per square inch (lb/in2 ) in coals from the Clarion coal zone to 500 lb/in2 for coals from the Upper Kittanning coal bed. The estimated maximum methane adsorption isotherms show that the coals from the Upper Kittanning coal bed and the Middle Kittanning coal zone are undersaturated in methane, but coals from the Clarion coal zone are close to saturation.

Geology and hydrocarbon potential in the state of Qatar, Arabian Gulf

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alsharhan, A.S.; Nairn, A.E.M.

The state of Qatar is situated in the southern Arabian Gulf and covers an area of 12,000 km{sup 2}. It is formed by a large, broad anticline, which is part of the regional south-southwest-north-northeast-trending Qatar-South Fars arch. The arch separates the two Infracambrian salt basins. The Dukhan field was the first discovery, made in 1939, in the Upper Jurassic limestones. Since then, a series of discoveries have been made so that Qatar has become one of the leading OPEC oil states. Hydrocarbon accumulations are widely dispersed throughout the stratigraphic column from upper Paleozoic to Cretaceous producing strata. The most prolificmore » reservoirs are the Permian and Mesozoic shelf carbonate sequences. Minor clastic reservoirs occur in the Albian and Paleozoic sequences. Seals, mainly anhydrite and shale. occur both intraformationally and regionally. Several stratigraphic intervals contain source rocks or potential source rocks. The Silurian shales arc the most likely source of the hydrocarbon stored in the upper Paleozoic clastics and carbonates. The upper Oxfordian-middle Kimmeridgian rocks formed in the extensive starved basin during the Mesozoic period of sea level rise. Total organic carbon ranges between 1 and 6%, with the sulfur content approximately 9%. The source material consists of sapropelic liptodetrinite and algae. The geological background of the sedimentary facies through geologic time, stratigraphy, and structural evolution which control source, and the subsequent timing and migration of large-scale hydrocarbon generation are presented in detail.« less

The Inskip Formation, the Harmony Formation, and the Havallah Sequence of Northwestern Nevada - An Interrelated Paleozoic Assemblage in the Home of the Sonoma Orogeny

USGS Publications Warehouse

Ketner, Keith B.

2008-01-01

An area between the towns of Winnemucca and Battle Mountain in northwestern Nevada, termed the arkosic triangle, includes the type areas of the middle to upper Paleozoic Inskip Formation and Havallah sequence, the Upper Devonian to Mississippian Harmony Formation, the Sonoma orogeny, and the Golconda thrust. According to an extensive body of scientific literature, the Havallah sequence, a diverse assemblage of oceanic rocks, was obducted onto the continent during the latest Permian or earliest Triassic Sonoma orogeny by way of the Golconda thrust. This has been the most commonly accepted theory for half a century, often cited but rarely challenged. The tectonic roles of the Inskip and Harmony Formations have remained uncertain, and they have never been fully integrated into the accepted theory. New, and newly interpreted, data are incompatible with the accepted theory and force comprehensive stratigraphic and tectonic concepts that include the Inskip and Harmony Formations as follows: middle to upper Paleozoic strata, including the Inskip, Harmony, and Havallah, form an interrelated assemblage that was deposited in a single basin on an autochthonous sequence of Cambrian, Ordovician, and lowest Silurian strata of the outer miogeocline. Sediments composing the Upper Devonian to Permian sequence entered the basin from both sides, arkosic sands, gravel, limestone olistoliths, and other detrital components entered from the west, and quartz, quartzite, chert, and other clasts from the east. Tectonic activity was expressed as: (1) Devonian uplift and erosion of part of the outer miogeocline; (2) Late Devonian depression of the same area, forming a trough, probably fault-bounded, in which the Inskip, Harmony, and Havallah were deposited; (3) production of intraformational and extrabasinal conglomerates derived from the basinal rocks; and (4) folding or tilting of the east side of the depositional basin in the Pennsylvanian. These middle to upper Paleozoic deposits were compressed in the Jurassic, causing east-verging thrusts in the eastern part of the depositional basin (Golconda thrust) and west-verging thrusts and folds in the western part. Hypotheses involving a far-traveled allochthon that was obducted from an ocean or back-arc basin are incompatible with modern observations and concepts.

Quantitative models for aggregate: some types and examples from Oklahoma carbonate rocks

USGS Publications Warehouse

Bliss, James D.

1999-01-01

Evaluation of data for three engineering variable--absorption, bulk specific gravity, and freeze-thaw durability (350 cycles)--was made for quarries in carbonate rocks in Oklahoma that supply aggregate. It was found that lower Palrozoic carbonate rocks (Cambrian through Devonian) are likely to make a better quality aggregate than upper Paleozoic (Mississippian to Permian) carbonate rocks. In addition, freeze-thaw durability can be forecast from absorption and is exemplary for lower Paleozoic carbonate rocks.

Assessment of Appalachian Basin Oil and Gas Resources: Utica-Lower Paleozoic Total Petroleum System

USGS Publications Warehouse

Ryder, Robert T.

2008-01-01

The Utica-Lower Paleozoic Total Petroleum System (TPS) is an important TPS identified in the 2002 U.S. Geological Survey (USGS) assessment of undiscovered, technically recoverable oil and gas resources in the Appalachian basin province (Milici and others, 2003). The TPS is named for the Upper Ordovician Utica Shale, which is the primary source rock, and for multiple lower Paleozoic sandstone and carbonate units that are the important reservoirs. Upper Cambrian through Upper Silurian petroleum-bearing strata that constitute the Utica-Lower Paleozoic TPS thicken eastward from about 2,700 ft at the western margin of the Appalachian basin to about 12,000 ft at the thrust-faulted eastern margin of the Appalachian basin. The Utica-Lower Paleozoic TPS covers approximately 170,000 mi2 of the Appalachian basin from northeastern Tennessee to southeastern New York and from central Ohio to eastern West Virginia. The boundary of the TPS is defined by the following geologic features: (1) the northern boundary (from central Ontario to northeastern New York) extends along the outcrop limit of the Utica Shale-Trenton Limestone; (2) the northeastern boundary (from southeastern New York, through southeastern Pennsylvania-western Maryland-easternmost West Virginia, to northern Virginia) extends along the eastern limit of the Utica Shale-Trenton Limestone in the thrust-faulted eastern margin of the Appalachian basin; (3) the southeastern boundary (from west-central and southwestern Virginia to eastern Tennessee) extends along the eastern limit of the Trenton Limestone in the thrust-faulted eastern margin of the Appalachian basin; (4) the southwestern boundary (from eastern Tennessee, through eastern Kentucky, to southwestern Ohio) extends along the approximate facies change from the Trenton Limestone with thin black shale interbeds (on the east) to the equivalent Lexington Limestone without black shale interbeds (on the west); (5) the northern part of the boundary in southwestern Ohio to the Indiana border extends along an arbitrary boundary between the Utica Shale of the Appalachian basin and the Utica Shale of the Sebree trough (Kolata and others, 2001); and (6) the northwestern boundary (from east-central Indiana, through northwesternmost Ohio and southeasternmost Michigan, to central Ontario) extends along the approximate southeastern boundary of the Michigan Basin. Although the Utica-Lower Paleozoic TPS extends into northwestern Ohio, southeastern Michigan, and northeastern Indiana, these areas have been assigned to the Michigan Basin (Swezey and others, 2005) and are outside the scope of this report. Furthermore, although the northern part of the Utica-Lower Paleozoic TPS extends across the Great Lakes (Lake Erie and Lake Ontario) into southern Ontario, Canada, only the undiscovered oil and gas resources in the U.S. waters of the Great Lakes have been included in the USGS assessment of the Utica-Lower Paleozoic TPS. This TPS is similar to the Point Pleasant-Brassfield petroleum system previously identified by Drozd and Cole (1994) in the Ohio part of the Appalachian basin.

Assessment of the petroleum, coal and geothermal resources of the economic community of West African States (ECOWAS) Region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattick, Robert E.; Spencer, Frank D.; Zihlman, Frederick N.

1982-01-01

Approximately 85 percent of the land area of the ECOWAS (Economic Community of West African States) region is covered by basement rocks (igneous and highly metamorphosed rocks) or relatively thin layers of Paleozoic, Upper Precambrian, and Continental Intercalaire sedimentary rocks. These areas have little or no petroleum potential. The ECOWAS region can be divided into 13 sedimentary basins on the basis of analysis of the geologic framework of Africa. These 13 basins can be further grouped into 8 categories on the basis of similarities in stratigraphy, geologic history, and probable hydrocarbon potential. The author has attempted to summarize the petroleummore » potential within the geologic framework of the region. The coal discoveries can be summarized as follows: the Carboniferous section in the Niger Basin; the Paleocene-Maestrichtian, Maestrichtian, and Eocene sections in the Niger Delta and Benin; the Maestrichtian section in the Senegal Basin; and the Pleistocene section in Sierra Leone. The only proved commercial deposits are the Paleocene-Maestrichtian and Maestrichtian subbituminous coal beds of the Niger Delta. Some of the lignite deposits of the Niger Delta and Senegal Basin, however, may be exploitable in the future. Published literature contains limited data on heat-flow values in the ECOWAS region. It is inferred, however, from the few values available and the regional geology that the development of geothermal resources, in general, would be uneconomical. Exceptions may include a geopressured zone in the Niger Delta and areas of recent tectonic activity in the Benue Trough and Cameroon. Development of the latter areas under present economic conditions is not feasible.« less

Detrital zircon provenance from three turbidite depocenters of the Middle-Upper Triassic Songpan-Ganzi complex, central China: Record of collisional tectonics, erosional exhumation, and sediment production

USGS Publications Warehouse

Weislogel, A.L.; Graham, S.A.; Chang, E.Z.; Wooden, J.L.; Gehrels, G.E.

2010-01-01

To test the idea that the voluminous upper Middle to Upper Triassic turbidite strata in the Songpan-Ganzi complex of central China archive a detrital record of Dabie ultrahigh-pressure (UHP) terrane unroofing, we report 2080 single detrital U-Pb zircon ages by sensitive high-resolution ion microprobe-reverse geometry (SHRIMP-RG) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis from 29 eastern Songpan-Ganzi complex sandstone samples. Low (<0.07) Th/U zircons, consistent with crystallization under UHP conditions, are rare in eastern Songpan-Ganzi complex zircon, and U-Pb ages of low Th/U zircons are incompatible with a Dabie terrane source. An unweighted pair group method with arithmetic mean nearest-neighbor analysis of Kolmogorov-Smirnov two-sample test results reveals that the eastern Songpan-Ganzi complex is not a single contiguous turbidite system but is instead composed of three subsidiary depocenters, each associated with distinct sediment sources. The northeastern depocenter contains zircon ages characterized by Paleozoic and bimodally distributed Precambrian zircon populations, which, together with south-to southeast-directed paleocurrent data, indicate derivation from the retro-side of the Qinling-Dabie (Q-D) collisional orogen wedge. In the central depocenter, the dominantly Paleozoic detrital zircon signature and south-to southwest-oriented paleocurrent indicators reflect a profusion of Paleozoic zircon grains. These data are interpreted to reflect an influx of material derived from erosion of Paleozoic supra-UHP rocks of the Dabie terrane in the eastern Qinling-Dabie orogen, which we speculate may have been enhanced by development of a monsoonal climate. This suggests that erosional unroofing played a significant role in the initial phase of UHP exhumation and likely influenced the petrotectonic and structural evolution of the Qinling-Dabie orogen, as evidenced by compressed Triassic isotherms/grads reported in the Huwan shear zone that bounds the Dabie terrane to the north. The central depocenter deposits reflect a later influx of bimodally distributed Precambrian zircon, signifying either a decrease in the influx of Paleozoic zircon grains due to stalled UHP exhumation and/or dilution of the same influx of Paleozoic zircons by spilling of Precambrian zircon from the northeastern depocenter into the central depocenter basin, perhaps due to infilling and bypass of sediment from the northern depocenter or due to initial collapse and constriction of the eastern Songpan-Ganzi complex basin. The southeastern depocenter of the eastern Songpan-Ganzi complex bears significant Paleozoic, Neoproterozoic, and Paleoproterozoic zircon populations derived from the South China block and Yidun arc complex, likely recording nascent uplift of the Longmenshan deformation belt due to impingement of the Yidun arc complex upon the western margin of the South China block. ?? 2010 Geological Society of America.

Variability of Mercury Content in Coal Matter From Coal Seams of The Upper Silesia Coal Basin

NASA Astrophysics Data System (ADS)

Wierzchowski, Krzysztof; Chećko, Jarosław; Pyka, Ireneusz

2017-12-01

The process of identifying and documenting the quality parameters of coal, as well as the conditions of coal deposition in the seam, is multi-stage and extremely expensive. The taking and analyzing of seam samples is the method of assessment of the quality and quantity parameters of coals in deep mines. Depending on the method of sampling, it offers quite precise assessment of the quality parameters of potential commercial coals. The main kind of seam samples under consideration are so-called "documentary seam samples", which exclude dirt bands and other seam contaminants. Mercury content in coal matter from the currently accessible and exploited coal seams of the Upper Silesian Coal Basin (USCB) was assessed. It was noted that the mercury content in coal seams decreases with the age of the seam and, to a lesser extent, seam deposition depth. Maps of the variation of mercury content in selected lithostratigraphic units (layers) of the Upper Silesian Coal Basin have been created.

Lower paleozoic of Baltic Area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haselton, T.M.; Surlyk, F.

The Baltic Sea offers a new and exciting petroleum play in northwestern Europe. The Kaliningrad province in the Soviet Union, which borders the Baltic Sea to the east, contains an estimated 3.5 billion bbl of recoverable oil from lower Paleozoic sandstones. To the south, in Poland, oil and gas fields are present along a trend that projects offshore into the Baltic. Two recent Petrobaltic wells in the southern Baltic have tested hydrocarbons from lower Paleozoic sandstone. Minor production comes from Ordovician reefs on the Swedish island of Gotland in the western Baltic. The Baltic synclise, which began subsiding in themore » late Precambrian, is a depression in the East European platform. Strate dip gently to the south where the Baltic Synclise terminates against a structurally complex border zone. Depth to the metamorphosed Precambrian basement is up to 4,000 m. Overlying basement is 200-300 m of upper Precambrian arkosic sandstone. The Lower Cambrian consists of shallow marine quartzites. During Middle and Late Camnbrian, restricted circulation resulted in anoxic conditions and the deposition of Alum shale. The Lower Ordovician consists of quartzites and shale. The Upper Ordovician includes sandstones and algal reefs. The Silurian contains marginal carbonates and shales. For the last 25 years, exploration in northwest Europe has concentrated on well-known Permian sandstone, Jurassic sandstone, and Cretaceous chalk plays. Extrapolation of trends known and exploited in eastern Europe could open an entirely new oil province in the lower Paleozoic in the Baltic.« less

Quality of economically extractable coal beds in the Gillette coal field as compared with other Tertiary coal beds in the Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Ellis, Margaret S.

2002-01-01

The Powder River Basin, and specifically the Gillette coal field, contains large quantities of economically extractable coal resources. These coal resources have low total sulfur content and ash yield, and most of the resources are subbituminous in rank. A recent U.S Geological Survey study of economically extractable coal in the Gillette coal field focused on five coal beds, the Wyodak rider, Upper Wyodak, Canyon, Lower Wyodak-Werner, and Gates/Kennedy. This report compares the coal quality of these economically extractable coal beds to coal in the Wyodak-Anderson coal zone in the Powder River Basin and in the Gillette coal field (Flores and others, 1999) and other produced coal in the Gillette coal field (Glass, 2000). The Upper Wyodak, Canyon, and Lower Wyodak/Werner beds are within the Wyodak-Anderson coal zone. Compared with all coal in the Wyodak-Anderson coal zone, both throughout the Powder River Basin and just within the Gillette coal field; the thick, persistent Upper Wyodak coal bed in the Gillette coal field has higher mean gross calorific value (8,569 Btu/lb), lower mean ash yield (5.8 percent), and lower mean total sulfur content (0.46 percent).

Precambrian U-Pb zircon ages in eclogites and garnet pyroxenites from South Brittany (France): an old oceanic crust in the West European Hercynian belt?

NASA Astrophysics Data System (ADS)

Peucat, J. J.; Vidal, Ph.; Godard, G.; Postaire, B.

1982-08-01

U-Pb zircon ages have been determined for two eclogites from the Vendée and for two garnet pyroxenites from the Baie d'Audierne. In an episodic Pb loss model, the two discordia would give upper intercept ages around 1300-1250 Ma and lower intercepts ages of 436-384 Ma. Two interpretations are proposed: (1) The 1250-1300 Ma ages may reflect an unspecified upper mantle event or process; the Paleozoic ages correspond to the tectonic emplacement of an eclogitic mantle fragment into the continental crust. (2) The protolith may have been extracted from the upper mantle 1250-1300 Ma ago and stored in a crustal environment until it was metamorphosed under high-pressure conditions around 400 Ma ago. This latter model is favoured by available geologic and isotopic data. Consequently, we propose that a 1300 Ma old oceanic crust was tectonicly incorporated into a sialic basement during the Proterozoic. This mixture was subsequently subducted during the Paleozoic.

Assessment of Appalachian basin oil and gas resources: Utica-Lower Paleozoic Total Petroleum System: Chapter G.10 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Ryder, Robert T.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

Both conventional oil and gas resources and continuous (unconventional) gas resources are present in the UticaLower Paleozoic TPS. Conventional oil and gas resources in the Utica-Lower Paleozoic TPS were assessed by the U.S. Geological Survey (USGS) in 2002 in the following assessment units (AU): (1) the Lower Paleozoic Carbonates in Thrust Belt AU, (2) the Knox Unconformity AU, (3) the Black River-Trenton Hydrothermal Dolomite AU, and (4) the Lockport Dolomite AU. The total estimated undiscovered oil and gas resources for these four AUs, at a mean value, was about 46 million barrels of oil (MMBO) and about 3 trillion cubic feet of gas (TCFG), respectively. In contrast, continuous (unconventional) gas resources in the TPS were assessed by the USGS in 2002 in four AUs associated with the “Clinton” sandstone, Medina sandstone, Medina Group sandstones, Tuscarora Sandstone, and sandstones in the Queenston Shale. The total estimated undiscovered gas for these four AUs, at a mean value, was about 26.8 TCFG. A hypothetical Utica Shale AU for oil(?) and continuous gas is identified in this report. In 2012, the Utica Shale was recognized by the USGS as a continuous AU and was assessed by Kirschbaum and others (2012).

The development of floristic provinciality during the Middle and Late Paleozoic

USGS Publications Warehouse

Wnuk, C.

1996-01-01

Phytogeographic reconstructions have been published for most Paleozoic series since the Pr??i??doli??, but there have been few attempts to synthesize this data into a comprehensive review of the characteristics and causes of the changing phytogeographic patterns for the whole Paleozoic history of the vascular flora. Existing floristic analyses have been compiled in this manuscript and the resulting data are used to reconstruct the evolution of floristic provinces since the Silurian. The earliest plant fossil records indicate that provinciality was characteristic of terrestrial vascular plant distributions right from the beginning of terrestrial colonization by vascular plants. This interpretation differs markedly from the views of many workers who still maintain that pre-Upper Carboniferous floras were uniform and cosmopolitan in distribution. Three of the four major phytogeographic units, i.e. Angara, Euramerica, and Gondwana, can be recognized in the earliest fossil floras. The fourth unit, Cathaysia, differentiated from Euramerica during the late Upper Carboniferous. Phytogeographic differentiation occurs in direct response to climatic gradients and physiographic barriers. As these gradients and barriers change, provincial boundaries expand and contract, fragment, reassemble and reassort. Phytogeographic units are dynamic through time. ?? 1996 Elsevier Science B.V. All rights reserved.

Lithospheric structure, composition, and thermal regime of the East European Craton: Implications for the subsidence of the Russian platform

USGS Publications Warehouse

Artemieva, I.M.

2003-01-01

A new mechanism for Paleozoic subsidence of the Russian, or East European, platform is suggested, since a model of lithosphere tilting during the Uralian subduction does not explain the post-Uralian sedimentation record. Alternatively, I propose that the Proterozoic and Paleozoic rifting (when a platform-scale Central Russia rift system and a set of Paleozoic rifts were formed) modified the structure and composition of cratonic lithosphere, and these tectono-magmatic events are responsible for the post-Uralian subsidence of the Russian platform. To support this hypothesis, (a) the thermal regime and the thickness of the lithosphere are analyzed, and (b) lithospheric density variations of non-thermal origin are calculated from free-board constraints. The results indicate that Proterozoic and Paleozoic rifting had different effects on the lithospheric structure and composition. (1) Proterozoic rifting is not reflected in the present thermal regime and did not cause significant lithosphere thinning (most of the Russian platform has lithospheric thickness of 150-180 km and the lithosphere of the NE Baltic Shield is 250-300 km thick). Paleozoic rifting resulted in pronounced lithospheric thinning (to 120-140 km) in the southern parts of the Russian platform. (2) Lithospheric density anomalies suggest that Proterozoic-Paleozoic rifting played an important role in the platform subsidence. The lithospheric mantle of the Archean-early Proterozoic part of the Baltic Shield is ??? 1.4 ?? 0.2% less dense than the typical Phanerozoic upper mantle. However, the density deficit in the subcrustal lithosphere of most of the Russian platform is only about (0.4-0.8) ?? 0.2% and decreases southwards to ???0%. Increased densities (likely associated with low depletion values) in the Russian platform suggest strong metasomatism of the cratonic lithosphere during rifting events, which led to its subsidence. It is proposed that only the lower part of the cratonic lithosphere was metasomatized as a result of Proterozoic rifting; the boundary between a depleted upper and more fertile lower layers can be at ca. 90-150 km depth and can produce a seismic pattern similar to the top of a seismic low-velocity zone. Paleozoic rifting has modified the entire lithospheric column and the regions affected are still subsiding. Published by Elsevier B.V.

Geology of the Deep Creek area, Washington, and its regional significance

USGS Publications Warehouse

Yates, Robert Giertz

1976-01-01

This report, although primarily concerned with the stratigraphy and structure of a lead-zinc mining district in northern Stevens County, Washington, discusses and integrates the geology of the region about the Deep Creek area. Although the study centers in an area of about 200 square miles immediately south of the International Boundary, the regional background comes from: (1)the previously undescribed Northport quadrangle to the west, (2) published reports and reconnaissance of the Metaline quadrangle to the east, and (3) from published reports and maps of a 16 mile wide area that lies to the north adjacent to these three quadrangles in British Columbia. The report is divided into three parts: (1) descriptions of rocks and structures of the Deep Creek area, (2) descriptions of the regional setting of the Deep Creek area, and (3) an analysis and interpretation of the depositional and tectonic events that produced the geologic features exposed today. In the Deep Creek area surficial deposits of sand and gravel of glacial origin cover much of the consolidated rocks, which range in age from greenschist of the late Precambrlan to albite granite of the Eocene. Three broad divisions of depositional history are represented: (1) Precambrian, (2) lower Paleozoic and (3) upper Paleozoic; the record of the Mesozoic and Eocene is fragmentary. The lower Paleozoic division is the only fossil-controlled sequence; the age of the other two divisions were established by less direct methods. Both Precambrian and upper Paleozoic sequences are dominated by fine-grained detrital sediments, the Precambrian tending towards the alumina-rich and the upper Paleozoic tending towards the black shale facies with high silica. Neither sequence has more than trivial amounts of coarse clastics. Both include limestones, but in minor abundance. The lower Paleozoic sequence, on the other hand, represents a progressive change in deposition. The sequence began during the very late Precambrian with the deposition of clean quartz sand. This was followed by the accumulation of a comparatively thin limestone unit succeeded by a thick shale. The shale grades into a thick carbonate unit which in turn is overlain by black graptolitic slates (Ordovician). This general order of deposition holds for the Cambro-Ordovician throughout the area. Precambrian rocks indigenous to the Deep Creek area, have undergone at least six tectonic events of greatly different intensities. The first three of these events are epeirogentic, the fourth involves intense folding, the fifth, crossfolding, and the sixth, block faulting without folding. These events are dated with varying degrees of precision. The two epeirogentic events of the Precambrian, one gentle folding at the beginning of Windermere time and the other high angle faulting and volcanism in mid-Windermere time, did little to deform or metamorphose the rocks. The third event consists of uplift of northern Idaho and adjacent Montana and westward decollement thrusting of essentially unfolded lower Paleozoic rocks. The decollement faulting is inferred to explain anomalous rock distribution and cannot be accurately dated. It occurred sometime after the Devonian and before the Jurassic. A late Paleozoic age is favored.

Relationships between sedimentation, depositional environments, and coal quality: upper Potomac coalfield, West Virginia and Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jake, T.R.

1987-09-01

Evaluations were made of sedimentation patterns and depositional environments from approximately 450 core logs and 225 surface exposures in the Upper Potomac coalfield. The relationships between the clastic depositional facies and the distribution and quality of the Bakerstown and upper Freeport coals were also investigated. Data from 61 Bakerstown and 35 upper Freeport coal samples from selected cores indicate a change from uniform coal quality to highly variable coal quality when moving from related interchannel and bay-fill facies to channel, channel-fill, levee, and crevasse-splay facies. Areas of uniform coal quality range from 20-26% ash and 55-62% fixed carbon (weight percent,more » dry basis), whereas areas of highly variable coal quality range from 26-54% ash and 33-55% fixed carbon. The channel and related facies represent areas where increased fresh water was introduced into the topogenous swamp system, causing increased microbial degradation and the concentration of authigenic minerals within the peat material. These conditions, combined with the introduction of detrital minerals, resulted in areas of lower quality coal.« less

Tectonics and hydrocarbon potential of the Barents Megatrough

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baturin, D.; Vinogradov, A.; Yunov, A.

1991-08-01

Interpretation of geophysical data shows that the geological structure of the Eastern Barents Shelf, named Barents Megatrough (BM), extends sublongitudinally almost from the Baltic shield to the Franz Josef Land archipelago. The earth crust within the axis part of the BM is attenuated up to 28-30 km, whereas in adjacent areas its thickness exceeds 35 km. The depression is filled with of more than 15 km of Upper Paleozoic, Mesozoic, and Cenozoic sediments overlying a folded basement of probable Caledonian age. Paleozoic sediments, with exception of the Upper Permian, are composed mainly of carbonates and evaporites. Mesozoic-Cenozoic sediments are mostlymore » terrigenous. The major force in the development of the BM was due to extensional tectonics. Three rifting phases are recognizable: Late Devonian-Early Carboniferous, Early Triassic, and Jurassic-Early Cretaceous. The principal features of the geologic structure and evolution of the BM during the late Paleozoic-Mesozoic correlate well with those of the Sverdup basin, Canadian Arctic. Significant quantity of Late Jurassic-Early Cretaceous basaltic dikes and sills were intruded within Triassic sequence during the third rifting phase. This was probably the main reason for trap disruption and hydrocarbon loss from Triassic structures. Lower Jurassic and Lower Cretaceous reservoir sandstones are most probably the main future objects for oil and gas discoveries within the BM. Upper Jurassic black shales are probably the main source rocks of the BM basin, as well as excellent structural traps for hydrocarbon fluids from the underlying sediments.« less

Metalliferous coals of the Westphalian A Joggins Formation, Cumberland basin, Nova Scotia, Canada: Petrology, geochemistry, and palynology

USGS Publications Warehouse

Hower, J.C.; Calder, J.H.; Eble, C.F.; Scott, A.C.; Robertson, J.D.; Blanchard, L.J.

2000-01-01

Five coals of Westphalian A (early Middle Pennsylvanian) age were sampled from the Joggins Formation section exposed along Chignecto Bay at Joggins, Nova Scotia. Coal beds along the bay were mined beginning in the early 17th century, yet there have been few detailed published investigation of the coal beds of this classic section. The lowermost coal, the Upper Coal 28 (Upper Fundy), is a high-vitrinite coal with a spore assemblage dominated by arboreous lycopsid spores with tree ferns subdominant. The upper portions of the coal bed have the highest ratio of well-preserved to poorly-preserved telinite of any of the coals investigated. Coal 19 ('clam coal') has 88% total vitrinite but, unlike the Fundy coal bed, the telinite has a poor preservation ratio and half the total vitrinite population comprises gelocollinite and vitrodetrinite. The latter coal bed is directly overlain by a basin-wide limestone bed. The Lower Kimberly coal shows good preservation of vitrinite with relatively abundant telinite among the total vitrinite. The Middle Kimberly coal, which underlies the tetrapod-bearing lycopsid trees found by Lyell and Dawson in 1852, exhibits an upward decrease in arboreous lycopod spores and an upward increase in the tree fern spore Punctatisporites minutus. Telinite preservation increases upwards in the Middle Kimberly but overall is well below the preservation ratio of the Upper Fundy coal bed. The coals all have high sulfur contents, yielding up to 13.7% total sulfur for the lower lithotype of the Upper Fundy coal bed. The Kimberly coals are not only high in total and pyritic sulfur, but also have high concentrations of chalcophile elements. Zinc, ranging up to 15,000 ppm (ash basis), is present as sphalerite in fusain lumens. Arsenic and lead each exceed 6000 ppm (ash basis) in separate lithotypes of the Kimberly coals. Together these data are consistent with elevated pH in planar mires. The source of the elemental enrichment in this presumed continental section is enigmatic. (C) 2000 Elsevier Science B.V. All rights reserved.Five coals of Westphalian A (early Middle Pennsylvanian) age were sampled from the Joggins Formation section exposed along Chigneto Bay at Joggins, Nova Scotia. All the coals were found to have high sulfur contents. Overall, the data obtained are consistent with elevated pH in planar mires.

Hydrogeologic Framework and Occurrence and Movement of Ground Water in the Upper Humboldt River Basin, Northeastern Nevada

USGS Publications Warehouse

Plume, Russell W.

2009-01-01

The upper Humboldt River basin encompasses 4,364 square miles in northeastern Nevada, and it comprises the headwaters area of the Humboldt River. Nearly all flow of the river originates in this area. The upper Humboldt River basin consists of several structural basins, in places greater than 5,000 feet deep, in which basin-fill deposits of Tertiary and Quaternary age and volcanic rocks of Tertiary age have accumulated. The bedrock of each structural basin and adjacent mountains is composed of carbonate and clastic sedimentary rocks of Paleozoic age and crystalline rocks of Paleozoic, Mesozoic and Cenozoic age. The permeability of bedrock generally is very low except for carbonate rocks, which can be very permeable where circulating ground water has widened fractures through geologic time. The principal aquifers in the upper Humboldt River basin occur within the water-bearing strata of the extensive older basin-fill deposits and the thinner, younger basin-fill deposits that underlie stream flood plains. Ground water in these aquifers moves from recharge areas along mountain fronts to discharge areas along stream flood plains, the largest of which is the Humboldt River flood plain. The river gains flow from ground-water seepage to its channel from a few miles west of Wells, Nevada, to the west boundary of the study area. Water levels in the upper Humboldt River basin fluctuate annually in response to the spring snowmelt and to the distribution of streamflow diverted for irrigation of crops and meadows. Water levels also have responded to extended periods (several years) of above or below average precipitation. As a result of infiltration from the South Fork Reservoir during the past 20 years, ground-water levels in basin-fill deposits have risen over an area as much as one mile beyond the reservoir and possibly even farther away in Paleozoic bedrock.

Results of coalbed-methane drilling, Meadowfill Landfill, Harrison County, West Virginia: Chapter G.4 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Ruppert, Leslie F.; Trippi, Michael H.; Fedorko, Nick; Grady, William C.; Eble, Cortland F.; Schuller, William A.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

Methane contents of desorbed gas from coal samples in the Meadowfill Landfill study area ranged from 14.87 to 98.73 percent (corrected for air contamination) for the Harlem coal bed and Clarion coal zone, respectively. Proportions of methane to the sum of the higher molecular weight hydrocarbons ranged from about 40 to 340 as the desorbed gas contained only a small percentage of higher weight hydrocarbons. Coalbed methane from the Upper Kittanning upper split and the Upper Kittanning coal beds is thermogenic in origin with isotopic composition of carbon (carbon 13, 13C) in methane (expressed as δ13C in units of parts per thousand (per mil) relative to the Vienna Peedee belemnite (VPDB) standard) ranging from -46.6 to -48.7 per mil. Coalbed methane from the Brush Creek and Upper Freeport coal beds and the Clarion coal zone contains some biogenic methane with δ13C values ranging from -51.05 to -51.56 per mil.

Composition and quality of coals in the Huaibei Coalfield, Anhui, China

USGS Publications Warehouse

Zheng, Lingyun; Liu, Gaisheng; Wang, L.; Chou, C.-L.

2008-01-01

The Huaibei Coalfield, Anhui Province, China, is one of the largest coalfields in China. The coals of Permian age are used mainly for power generation. Coal compositions and 47 trace elements of the No. 10 Coal of the Shanxi Formation, the No. 7, 5, and 4 Coals of the Lower Shihezi Formation, and the No. 3 Coal of the Upper Shihezi Formation from the Huaibei Coalfield were studied. The results indicate that the Huaibei coals have low ash, moisture, and sulfur contents, but high volatile matter and calorific value. The ash yield increases stratigraphically upwards, but the volatile matter and total sulfur contents show a slight decrease from the lower to upper seams. Magmatic intrusion into the No. 5 Coal resulted in high ash, volatile matter, and calorific value, but low moisture value in the coal. Among the studied 47 trace elements, Ba, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Th, U, V, and Zn are of environmental concerns. Four elements Hg, Mo, Zn, and Sb are clearly enriched in the coals as compared with the upper continental crust. ?? 2007 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sari, A.; Geze, Y.

The studied area is a lake basin located in Bolu basin in Turkey. In the basin, from Upper Cretaceous to Upper Miocene 3,000-m thickness sediments were deposited. Upper Miocene Himmetoglu formation consisted of sandstone, claystone, and marl. To the middle level of the formation are located coal, bituminous limestone, and bituminous shales. In the basin, there are two coal beds whose thicknesses range from 1 to 13 m. The coals are easily breakable and black in color. In the coal beds exists some bituminous limestone and bituminous shales, and their thicknesses are between 5 and 45 cm. The amount ofmore » organic matter of the bituminous rocks from the Upper Miocene Himmetoglu formation are between 6.83 and 56.34 wt%, and the amount of organic matter of the bituminous limestone from the formation are between 13.58 and 57.16 wt%. These values indicate that these rocks have very good source potential. According to hydrogen index (HI), S2/S3, HI-T{sub max}, and HI-OI (oxygen index) parameters, kerogen types of the bituminous rocks and coals belonging to Upper Miocene Himmetoglu formation are Type I, Type II, and Type III. In accordance with HI, S2/S3, HI-T{sub max}, and HI-OI parameters, the bituminous rocks and coals from the Upper Miocene Himmetoglu formation are mostly immature.« less

Phosphorus minerals in tonstein; coal seam 405 at Sośnica-Makoszowy coal mine, Upper Silesia, southern Poland

NASA Astrophysics Data System (ADS)

Kokowska-Pawłowska, Magdalena; Nowak, Jacek

2013-06-01

Kokowska-Pawłowska, M. and Nowak, J. 2013. Phosphorus minerals in tonstein; coal seam 405 at Sośnica- Makoszowy coal mine, Upper Silesia, southern Poland. Acta Geologica Polonica, 63 (2), 271-281. Warszawa. The paper presents results of research on tonstein, which constitutes an interburden in coal seam 405 at the Sośnica- Makoszowy coal mine, Makoszowy field (mining level 600 m), Upper Silesia, southern Poland. The mineral and chemical compositions of the tonstein differ from the typical compositions described earlier for tonsteins from Upper Silesia Coal Basin area. Additionally, minerals present in the tonsteins include kaolinite, quartz, kaolinitised biotite and feldspars. The presence of the phosphatic minerals apatite and goyazite has been recognized. The presence of gorceixite and crandallite is also possible. The contents of CaO (5.66 wt%) and P2O5 (6.2 wt%) are remarkably high. Analysis of selected trace elements demonstrated high contents of Sr (4937 ppm) and Ba (4300 ppm), related to the phosphatic minerals. On the basis of mineral composition the tonstein has been identified as a crystalline tonstein, transitional to a multiplied one.

Palynology of the Lost Branch Formation of Kansas - New insights on the major floral transition at the Middle-Upper Pennsylvanian boundary

USGS Publications Warehouse

Peppers, R.A.

1997-01-01

Palynological assemblages from two outcrops of the upper part of the Memorial Formation, the Lost Branch Formation, and the overlying Hepler unit in Kansas were examined to discover which stratigraphic interval marks the change from the lycopod-dominated coal swamp floras of Middle Pennsylvanian (Westphalian D) age to the fern-dominated coal swamp floras of Late Pennsylvanian (Stephanian) age. The Lost Branch Formation underlies the Pleasanton Group, whose base is recognized as the Middle-Upper Pennsylvanian boundary in the Midcontinent. The outcrops include the youngest Middle Pennsylvanian coal (Dawson), just below the Lost Branch Formation, and the oldest Upper Pennsylvanian coal ('Hepler') within the Pleasanton Group. Lycospora dominates the spore assemblage in the Middle Pennsylvanian (Desmoinesian) Dawson coal in the Memorial Shale and is abundant in shale between the coal and just below the Glenpool limestone bed at the top of the Lost Branch Formation. It is rare between the limestone and the Upper Pennsylvanian (Missourian) 'Hepler' coal. Granasporites medius and Thymospora pseudothiessenii disappear below the limestone. The 'Hepler' coal is dominated by fern and seed fern spores Cyclogranisporites and Apiculatasporites, and the sphenopsid spore Calamospora is third in abundance. Florinites, Potonieisporites and other gymnospermic monosaccate pollen are abundant between the two coals. Bisaccate conifer-like pollen, such as Protohaploxipinus, are most common between the Dawson coal and Glenpool limestone, but Wilsonites, which is thought to have been produced by seed ferns, is very abundant from the Glenpool limestone to the 'Hepler' coal. On the basis of macroinvertebrate evidence, the Glenpool limestone is Middle Pennsylvanian in age, but the palynological evidence indicates that the floral change took place slightly before deposition of the limestone. Thus, the major change in climate that occurred near the Middle-Upper Pennsylvanian boundary apparently affected the floras earlier than the faunas. The floral change cannot be explained as resulting from a major marine regression and hiatus because the change is recorded in a marine section within a single transgressive-regressive sequence.

The Republic of the Philippines coalbed methane assessment: based on seventeen high pressure methane adsorption isotherms

USGS Publications Warehouse

Flores, Romeo M.; Stricker, Gary D.; Papasin, Ramon F.; Pendon, Ronaldo R.; del Rosario, Rogelio A.; Malapitan, Ruel T.; Pastor, Michael S.; Altomea, Elmer A.; Cuaresma, Federico; Malapitan, Armando S.; Mortos, Benjamin R.; Tilos, Elizabeth N.

2006-01-01

Introduction: The Republic of the Philippines has some 19 coal districts that contain coal deposits ranging from Eocene to Pleistocene in age. These coal districts include: (1) Catanduanes (Eocene); (2) Cebu, Zamboanga Sibuguey, Bukidnon, Maguindanao, Sarangani, and Surigao (Oligocene to Miocene); (3) Batan Island, Masbate, Semirara (including Mindoro), and Quezon-Polilio (lower-upper Miocene); (4) Davao, Negros, and Sorsogon (middle-upper Miocene); (5) Cotabato (lower Miocene-lower Pliocene), Cagayan-Isabella, and Quirino (upper Miocene-Pliocene); (6) Sultan Kudarat (upper Miocene-Pleistocene); and (7) Samar-Leyte (lower Pliocene-Pleistocene). In general, coal rank is directly related to the age of the deposits - for example, the Eocene coal is semi-anthracite and the Pliocene-Pleistocene coal is lignite. Total coal resources in these 19 coal districts, which are compiled by the Geothermal and Coal Resources Development Division (GCRDD) of the Department of Energy of the Philippines, are estimated at a minimum of 2,268.4 million metric tonnes (MMT) (approximately 2.3 billion metric tones). The largest resource (550 MMT) is the subbituminous coal in the Semirara (including Mindoro) coal district, and the smallest (0.7 MMT) is the lignite-subbituminous coal in the Quirino coal district. The combined lignite and subbituminous coal resources, using the classification by GCRDD and including Semirara and Surigao coal districts, are about 1,899.2 MMT, which make up about 84 percent of the total coal resources of the Philippines. The remaining resources are composed of bituminous and semi-anthracite coal. The subbituminous coal of Semirara Island in the Mindoro- Semirara coal district (fig. 2) is known to contain coalbed methane (CBM), with the coal being comparable in gas content and adsorption isotherms to the coal of the Paleocene Fort Union Formation in the Powder River Basin in Wyoming, USA (Flores and others, 2005). As a consequence, the presence of CBM in the Semirara coal led to the present study of determining the adsorption isotherms, or gas (CBM) holding or storage capacity, of coal beds of various ages from selected coal districts in the Philippines. Samples for the study were collected from the Batan Island, Catanduanes, Cagayan-Isabella, Cebu, Negros, Samar, Semirara, Cotabato, Surigao, and Malangas coalfield of the Zamboanga Sibuguey coal districts by five field geology teams from the GCRDD.

Clastic rocks associated with the Midcontinent rift system in Iowa

USGS Publications Warehouse

Anderson, Raymond R.; McKay, Robert M.

1997-01-01

The Middle Proterozoic Midcontinent Rift System (MRS) of North America is a failed rift that formed in response to region-wide stresses about 1,100 Ma. In Iowa, the MRS is buried beneath 2,200?3,500 ft of Paleozoic and Mesozoic sedimentary rocks and Quaternary glaciogenic deposits. An extremely large volume of sediments was deposited within basins associated with the rift at several stages during its development. Although the uplift of a rift-axial horst resulted in the erosional removal of most of these clastic rocks from the central region of the MRS in Iowa, thick sequences are preserved in a series of horst-bounding basins. Recent studies incorporating petrographic analysis, geophysical modeling, and other analytical procedures have led to the establishment of a preliminary stratigraphy for these clastic rocks and interpretations of basin geometries. This information has allowed the refinement of existing theories and history of MRS formation in Iowa. Additionally, drill samples previously interpreted as indicating the existence of early Paleozoic basins overlying the Proterozoic MRS basins were re-examined. Samples previously interpreted as deep-lying Paleozoic rocks are now known to have caved from upper levels of the drillhole and were out of stratigraphic position. No deep Paleozoic basins exist in this area. These investigations led to the development of petrographic parameters useful in differentiating the Proterozoic MRS Red clastics from Paleozoic clastic rocks having similar lithologies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sener, M.; Tufekci, K.

In Turkey, the three power plants (Yataan, Yenikoy, and Kemerkoy) in the southwestern part of Anatolia use Upper Miocene-Pliocene coal and cause environmental pollution in the winter. For this reason, some considerations have been given to the injection of CO{sub 2} from the power plants into the crust. A research project has been put into the practice for decreasing of global warming. Karstification and geological features, which are included in very thick carbonate rocks (a thickness over 2,000 m and limestone, dolomite, and marble from Paleozoic to Pliocene), and faults-lineaments have been considered as very important agents that will affectmore » the injection of CO{sub 2}. The micro- and macro-karstification and lineament of the region have been studied, and the rocks of the area have been grouped into two classes based on the appropriateness of karstification as suitable and unsuitable rocks. Karstic and geological features (rocks and dislocation lines) have been compared together in a Geographic Information Systems (GIS); thus, by taking note of the geological-geomorphological characteristics of the area, a case study has been proposed for the CO{sub 2} injection from the Gokova power plant emissions with GIS applications, and suitable areas for the injection have been determined for further research.« less

23. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN Keystone Coal Buyers Catalog, 1922, VIEW SOUTH, COMMUNITY OF ETHEL; ETHEL COAL COMPANY MINE SUPPLY BUILDING IS LOCATED IN MID-GROUND IN CENTER PARTIALLY OBSCURED BY ROOF OF HOUSE IN FOREGROUND - Ethel Coal Company & Supply Building, Left fork of Dingess Run (Ethel Hollow), Ethel, Logan County, WV

Huminite reflectance measurements of Paleocene and Upper Cretaceous coals from borehole cuttings, Zavala and Dimmit counties, South Texas

USGS Publications Warehouse

Hackley, Paul C.; Hook, Robert W.; Warwick, Peter D.

2005-01-01

The reflectance of huminite in 19 cuttings samples was determined in support of ongoing investigations into the coal bed methane potential of subsurface Paleocene and Upper Cretaceous coals of South Texas. Coal cuttings were obtained from the Core Research Center of the Bureau of Economic Geology, The University of Texas at Austin. Geophysical logs, mud-gas logs, driller's logs, completion cards, and scout tickets were used to select potentially coal-bearing sample suites and to identify specific sample depths. Reflectance measurements indicate coals of subbituminous rank are present in a wider area in South Texas than previously recognized.

Mineralogy and geochemistry of the No. 6 Coal (Pennsylvanian) in the Junger Coalfield, Ordos Basin, China

USGS Publications Warehouse

Dai, S.; Ren, D.; Chou, C.-L.; Li, S.; Jiang, Y.

2006-01-01

This paper discusses the mineralogy and geochemistry of the No. 6 Coal (Pennsylvanian) in the Junger Coalfield, Ordos Basin, China. The results show that the vitrinite reflectance (0.58%) is lowest and the proportions of inertinite and liptinite (37.4% and 7.1%, respectively) in the No. 6 Coal of the Junger Coalfield are highest among all of the Late Paleozoic coals in the Ordos Basin. The No. 6 Coal may be divided vertically into four sections based on their mineral compositions and elemental concentrations. A high boehmite content (mean 6.1%) was identified in the No. 6 Coal. The minerals associated with the boehmite in the coal include goyazite, rutile, zircon, and Pb-bearing minerals (galena, clausthalite, and selenio-galena). The boehmite is derived from weathered and oxidized bauxite in the weathered crust of the underlying Benxi Formation (Pennsylvanian). A high Pb-bearing mineral content of samples ZG6-2 and ZG6-3 is likely of hydrothermal origin. The No. 6 coal is enriched in Ga (44.8 ??g/g), Se (8.2 ??g/g), Sr (423 ??g/g), Zr (234 ??g/g), REEs (193.3 ??g/g), Hg (0.35 ??g/g), Pb (35.7 ??g/ g), and Th (17.8 ??g/g). Gallium and Th in the No. 6 Coal mainly occur in boehmite, and the Pb-bearing selenide and sulfide minerals contribute not only to Se and Pb contents in the coal, but also probably to Hg content. A high Zr content is attributed to the presence of zircon, and Sr is related to goyazite. The REEs in the coal are supplied from the sediment-source region, and the REEs leached from the adjacent partings by groundwater. ?? 2005 Elsevier B.V. All rights reserved.

Upper crust beneath the central Illinois basin, United States

USGS Publications Warehouse

McBride, J.H.; Kolata, Dennis R.

1999-01-01

Newly available industry seismic reflection data provide critical information for understanding the structure and origin of the upper crust (0-12 km depth) beneath the central Illinois basin and the seismic-tectonic framework north of the New Madrid seismic zone in the central Mississippi Valley. Mapping of reflector sequences furnishes the first broad three-dimensional perspective of the structure of Precambrian basement beneath the central United States Midcontinent. The highly coherent basement reflectivity is expressed as a synformal wedge of dipping and subhorizontal reflections situated beneath the center of the Illinois basin that thickens and deepens to the northeast (e.g., 0 to ???5.3 km thickness along a 123 km south to north line). The thickening trend of the wedge qualitatively mimics the northward thickening of the Late Cambrian Mt. Simon Sandstone; however, other Paleozoic units in the Illinois basin generally thicken southward into the basin center. The seismic data also reveal an anomalous subsequence defined by a spoon-shaped distribution of disrupted reflections located along the southern margin of the wedge. The boundaries of this subsequence are marked by distinct steeply dipping reflections (possible thrust faults?) that continue or project up to antiformal disruptions of lower Paleozoic marker reflectors, suggesting Paleozoic or possibly later tectonic reactivation of Precambrian structure. The areal extent of the subsequence appears to roughly correspond to an anomalous concentration of larger magnitude upper to middle crustal earthquakes. There are multiple hypotheses for the origin of the Precambrian reflectivity, including basaltic flows or sills interlayered with clastic sediments and/or emplaced within felsic igneous rocks. Such explanations are analogous to nearby Keweenawan rift-related volcanism and sedimentation, which initiated during Proterozoic rifting, and were followed eventually by reverse faulting along the rift margins caused by Grenville compression.

22. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN Keystone Coal Buyers Catalog, 1922, VIEW SOUTH, COMMUNITY OF ETHEL; ETHEL COAL COMPANY MINE SUPPLY BUILDING IS LOCATED IN MID-GROUND LEFT OF CENTER PARTIALLY OBSCURED BY ROOF OF HOUSE IN FOREGROUND - Ethel Coal Company & Supply Building, Left fork of Dingess Run (Ethel Hollow), Ethel, Logan County, WV

Paleobiogeography, high-resolution stratigraphy, and the future of Paleozoic biostratigraphy: Fine-scale diachroneity of the Wenlock (Silurian) conodont Kockelella walliseri

USGS Publications Warehouse

Cramer, Bradley D.; Kleffner, Mark A.; Brett, Carlton E.; McLaughlin, P.I.; Jeppsson, Lennart; Munnecke, Axel; Samtleben, Christian

2010-01-01

The Wenlock Epoch of the Silurian Period has become one of the chronostratigraphically best-constrained intervals of the Paleozoic. The integration of multiple chronostratigraphic tools, such as conodont and graptolite biostratigraphy, sequence stratigraphy, and ??13Ccarb chemostratigraphy, has greatly improved global chronostratigraphic correlation and portions of the Wenlock can now be correlated with precision better than ??100kyr. Additionally, such detailed and integrated chronostratigraphy provides an opportunity to evaluate the fidelity of individual chronostratigraphic tools. Here, we use conodont biostratigraphy, sequence stratigraphy and carbon isotope (??13Ccarb) chemostratigraphy to demonstrate that the conodont Kockelella walliseri, an important guide fossil for middle and upper Sheinwoodian strata (lower stage of the Wenlock Series), first appears at least one full stratigraphic sequence lower in Laurentia than in Baltica. Rather than serving as a demonstration of the unreliability of conodont biostratigraphy, this example serves to demonstrate the promise of high-resolution Paleozoic stratigraphy. The temporal difference between the two first occurrences was likely less than 1million years, and although it is conceptually understood that speciation and colonization must have been non-instantaneous events, Paleozoic paleobiogeographic variability on such short timescales (tens to hundreds of kyr) traditionally has been ignored or considered to be of little practical importance. The expansion of high-resolution Paleozoic stratigraphy in the future will require robust biostratigraphic zonations that embrace the integration of multiple chronostratigraphic tools as well as the paleobiogeographic variability in ranges that they will inevitably demonstrate. In addition, a better understanding of the paleobiogeographic migration histories of marine organisms will provide a unique tool for future Paleozoic paleoceanography and paleobiology research. ?? 2010 Elsevier B.V.

Tectonics, basin analysis and organic geochemical attributes of Permian through Mesozoic deposits and their derivative oils of the Turpan-Hami basin, northwestern China

NASA Astrophysics Data System (ADS)

Greene, Todd Jeremy

The Turpan-Hami basin is a major physiographic and geologic feature of northwest China, yet considerable uncertainty exists as to the timing of its inception, its late Paleozoic and Mesozoic tectonic history, and the relationship of its petroleum systems to those of the nearby Junggar basin. Mesozoic sedimentary fades, regional unconformities, sediment dispersal patterns, and sediment compositions within the Turpan-Hami and southern Junggar basins suggest that these basins were initially separated between Early Triassic and Early Jurassic time. Prior to separation, Upper Permian profundal lacustrine and fan-delta fades and Triassic coarse-grained braided-fluvial/alluvial fades were deposited across a contiguous Junggar-Turpan-Hami basin. Permian through Triassic fades were derived mainly from the Tian Shan to the south as indicated by northward-directed paleocurrent directions and geochemical provenance of granitoid cobbles. Lower through Middle Jurassic strata begin to reflect ponded coal-forming, lake-plain environments within the Turpan-Hami basin. A sharp change in sedimentary-lithic-rich Lower Jurassic sandstone followed by a return to lithic volcanic-rich Middle Jurassic sandstone points to the initial uplift and unroofing of the largely andesitic Bogda Shan range, which first shed its sedimentary cover as it emerged to become the partition between the Turpan-Hami and southern Junggar basins. In Turpan-Hami, source rock age is one of three major statistically significant discriminators of effective source rocks in the basin. A newly developed biomarker parameter appears to track conifer evolution and can distinguish Permian rocks and their correlative oils from Jurassic coals and mudrocks, and their derivative oils. Source fades is a second key control on petroleum occurrence and character. By erecting rock-to-oil correlation models, the biomarker parameters separate oil families into end-member groups: Group 1 oils---Lower/Middle Jurassic peatland/swamp fades, Group 2 oils---Lower/Middle Jurassic marginal lacustrine fades, and Group 3 oils---Upper Permian lacusbine fades. Burial history exercises a third major control on petroleum in the Turpan-Hami basin. While relatively uninterrupted deep burial in the Tabei Depression exhausted Upper Permian source rocks and brought Lower/Middle Jurassic rocks well into the oil generative window, Late Jurassic uplift in the Tainan Depression eroded much of the Lower/Middle Jurassic section and preserved Upper Permian sourced oils as biodegraded, relict, heavy oils.* *This dissertation includes a CD that is multimedia (contains text and other applications that are not available in a printed format). The CD requires the following applications: Adobe Acrobat, UNIX.

Paleozoic shale gas resources in the Sichuan Basin, China

USGS Publications Warehouse

Potter, Christopher J.

2018-01-01

The Sichuan Basin, China, is commonly considered to contain the world’s most abundant shale gas resources. Although its Paleozoic marine shales share many basic characteristics with successful United States gas shales, numerous geologic uncertainties exist, and Sichuan Basin shale gas production is nascent. Gas retention was likely compromised by the age of the shale reservoirs, multiple uplifts and orogenies, and migration pathways along unconformities. High thermal maturities raise questions about gas storage potential in lower Paleozoic shales. Given these uncertainties, a new look at Sichuan Basin shale gas resources is advantageous. As part of a systematic effort to quantitatively assess continuous oil and gas resources in priority basins worldwide, the US Geological Survey (USGS) completed an assessment of Paleozoic shale gas in the Sichuan Basin in 2015. Three organic-rich marine Paleozoic shale intervals meet the USGS geologic criteria for quantitative assessment of shale gas resources: the lower Cambrian Qiongzhusi Formation, the uppermost Ordovician Wufeng through lowermost Silurian Longmaxi Formations (currently producing shale gas), and the upper Permian Longtan and Dalong Formations. This study defined geologically based assessment units and calculated probabilistic distributions of technically recoverable shale gas resources using the USGS well productivity–based method. For six assessment units evaluated in 2015, the USGS estimated a mean value of 23.9 tcf (677 billion cubic meters) of undiscovered, technically recoverable shale gas. This result is considerably lower than volumes calculated in previous shale gas assessments of the Sichuan Basin, highlighting a need for caution in this geologically challenging setting.

Palynomorphs of Permian Gondwana coal from borehole GDH-38, Barapukuria Coal Basin, Bangladesh

USGS Publications Warehouse

Akhtar, A.; Kosanke, R.M.

2000-01-01

Thirty-two core samples of Permian Gondwana coal from three coal beds of borehole GDH-38, Barapukuria Coal Basin, Dinajpur, the north-northwestern part of Bangladesh, have been collected for palynological analysis. All samples except one yielded palynomorphs and some samples contain well-preserved and abundant palynomorphs of the gymnospermal and cryptogamic groups that are considered to be useful for future correlation studies. The lower coal bed (331.6-372.5 m) can easily be differentiated from the upper two coal beds by the presence of Alisporites, Cordaitina, Corisaccites, Hamiapollenites, Leuckisporites, Nuskoisporites, Tumoripollenites, Vestgisporites and Vittatina. It is difficult to palynologically differentiate the middle (198.1-208 m) and upper (162.3-172.9 m) coal beds as they contain a very limited number of specimens by which they can be identified. The middle bed is distinguished by the presence of Microbaculispora and Weylandites and the upper bed by the presence of a single taxon Acanthotriletes. Some of the vesiculate or saccate taxa extracted from these coal beds are typical of those occurring in Permian strata of Gondwana in India, South Africa, South America, Russia, Australia and Antarctica. They are thought to be derived from Glossopteris flora, which is characterised by an abundance of Pteridospermic plants of the gymnosperm group. ?? 2000 Elsevier Science Limited. All rights reserved.

Anatomically preserved marattiales from coal swamps of the Desmoinesian and Missourian of the midcontinent United States: Systematics, ecology and evolution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lesnikowska, A.D.

1989-01-01

Eleven species-level assemblages of stems, frond members and fertile foliage of anatomically preserved Marattiales are proposed, based on specimens in coal balls from 16 coals in the Desmoinesian and Missourian (Westphalian D and Stephanian) of the Illinois, Forest City and Arkoma Basins. Four new combinations, Psaronius calicifolius (Millay) Lesnikowska, and Psaronius gnomus (Lesnikowska Millay) Lesnikowska, Psaronius illinoensis (Eqart) Lesnikowska, and Psaronius minor (Hoskins) Lesnikowska are made to accommodate well documented assemblages and seven are treated informally. The taxonomy of the fertile foliage is revised as follows: Scolecopteris dispora Lesnikowska sp. nov. is described from an Iowa coal and Scolecopteris parkerensismore » Lesnikowska sp. nov. from the Parker Coal of Indiana. Scolecopteris fragilis is made a synonym of S. mamayi, and S. revoluta, and S. saharaensis synonyms of S. minor. The type and Middle Pennsylvanian specimens of Scolecopteris parvifolia belong in S. minor but the Upper Pennsylvanian specimens are S. illinoensis. Only one species occurs in both the Middle and the Upper Pennsylvanian; the extinction event near the Middle/Upper Pennsylvanian boundary extended to coal-swamp Marattiales as well as tree lycopods. The Upper Pennsylvanian tree ferns are interpreted as derived from clastic-swamp species that recolonized the coal-swamp habitat after this extinction. Upper Pennsylvanian tree ferns were significantly larger than Middle Pennsylvanian ones and were characterized by a massive root mantle whereas as least one Middle Pennsylvanian species lacked a root mantle and had a scrambling habit. Biomass allocation to reproduction was significantly greater in the Middle Pennsylvanian species.« less

Assessment of undiscovered continuous gas resources of the Ordos Basin Province, China, 2015

USGS Publications Warehouse

Charpentier, Ronald R.; Klett, Timothy R.; Schenk, Christopher J.; Brownfield, Michael E.; Gaswirth, Stephanie B.; Le, Phuong A.; Leathers-Miller, Heidi M.; Marra, Kristen R.; Mercier, Tracey J.

2016-01-11

Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean resources of 28 trillion cubic feet of tight gas and 5.6 trillion cubic feet of coalbed gas in upper Paleozoic rocks in the Ordos Basin Province, China.

Coal systems analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Warwick, P.D.

This collection of papers provides an introduction to the concept of coal systems analysis and contains examples of how coal systems analysis can be used to understand, characterize, and evaluate coal and coal gas resources. Chapter are: Coal systems analysis: A new approach to the understanding of coal formation, coal quality and environmental considerations, and coal as a source rock for hydrocarbons by Peter D. Warwick. Appalachian coal assessment: Defining the coal systems of the Appalachian Basin by Robert C. Milici. Subtle structural influences on coal thickness and distribution: Examples from the Lower Broas-Stockton coal (Middle Pennsylvanian), Eastern Kentucky Coalmore » Field, USA by Stephen F. Greb, Cortland F. Eble, and J.C. Hower. Palynology in coal systems analysis The key to floras, climate, and stratigraphy of coal-forming environments by Douglas J. Nichols. A comparison of late Paleocene and late Eocene lignite depositional systems using palynology, upper Wilcox and upper Jackson Groups, east-central Texas by Jennifer M.K. O'Keefe, Recep H. Sancay, Anne L. Raymond, and Thomas E. Yancey. New insights on the hydrocarbon system of the Fruitland Formation coal beds, northern San Juan Basin, Colorado and New Mexico, USA by W.C. Riese, William L. Pelzmann, and Glen T. Snyder.« less

Off-platform Silurian sequences in the Ambler River quadrangle: A section in Geologic studies in Alaska by the U.S. Geological Survey during 1987

USGS Publications Warehouse

Dumoulin, Julie A.; Harris, Anita G.

1988-01-01

Lithofacies changes in coeval upper Paleozoic rocks have been used to unravel the tectonic history of northern Alaska (for example, Mayfield and others, 1983). Conodont biostratigraphy and detailed petrologic studies are now revealing facies differences in lower Paleozoic rocks that can also be used to constrain their tectono-sedimentary framework (Dumoulin and Harris, 1987). A basic element of basin analysis is the discrimination of shallow-water shelf and platform sequences from deeper water slope and basinal deposits. This report documents several new localities of deeper water, off-platform Silurian deposits in the Ambler River quadrangle and briefly outlines some of their paleogeographic implications.

Method of operating a coal gasifier

DOEpatents

Blaskowski, Henry J.

1979-01-01

A method of operating an entrained flow coal gasifier which comprises the steps of firing coal at two levels in a combustion zone with near stoichiometric air, removing molten ash from the combustion zone, conveying combustion products upwardly from the combustion zone through a reduction zone, injecting additional coal into the combustion products in the reduction zone and gasifying at least a portion of the coal to form low BTU gas, conveying the gas to a point of use, including also reducing gasifier output by modifying the ratio of air to coal supplied to the upper level of the combustion zone so that the ratio becomes increasingly substoichiometric thereby extending the gasification of coal from the reduction zone into the upper level of the combustion zone, and maintaining the lower level of coal in the combustion zone at near stoichiometric conditions so as to provide sufficient heat to maintain effective slagging conditions.

The upper pennsylvanian pittsburgh coal bed: Resources and mine models

USGS Publications Warehouse

Watson, W.D.; Ruppert, L.F.; Tewalt, S.J.; Bragg, L.J.

2001-01-01

The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed, which indicates that after subtracting minedout coal, 16 billion short tons (14 billion tonnes) remain of the original 34 billion short tons (31 billion tonnes) of coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only 12 billion short tons (11 billion tonnes) are available for mining. Our assessment models estimate that up to 0.61 billion short tons (0.55 billion tonnes), 2.7 billion short tons (2.4 billion tonnes), and 8.5 billion short tons (7.7 billion tonnes) could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the United States. ?? 2001 International Association for Mathematical Geology.

Coal depositional models in some Tertiary and Cretaceous coal fields in the U.S. Western Interior

USGS Publications Warehouse

Flores, R.M.

1979-01-01

Detailed stratigraphic and sedimentological studies of the Tertiary Tongue River Member of the Fort Union Formation in the Powder River Basin, Wyoming, and the Cretaceous Blackhawk Formation and Star Point Sandstone in the Wasatch Plateau, Utah, indicate that the depositional environments of coal played a major role in controlling coal thickness, lateral continuity, potential minability, and type of floor and roof rocks. The potentially minable, thick coal beds of the Tongue River Member were primarily formed in long-lived floodbasin backswamps of upper alluvial plain environment. Avulsion of meandering fluvial channels contributed to the erratic lateral extent of coals in this environment. Laterally extensive coals formed in floodbasin backswamps of a lower alluvial plain environment; however, interruption by overbank and crevasse-splay sedimentation produced highly split and merging coal beds. Lacustrine sedimentation common to the lower alluvial plain, similar to the lake-covered lower alluvial valley of the Atchafalaya River Basin, is related to a high-constructive delta. In contrast to these alluvial coals are the deltaic coal deposits of the Blackhawk Formation. The formation consists of three coal populations: upper delta plain, lower delta plain, and 'back-barrier'. Coals of the lower delta plain are thick and laterally extensive, in contrast to those of the upper delta plain and 'back-barrier', which contain abundant, very thin and laterally discontinuous carbonaceous shale partings. The reworking of the delta-front sediments of the Star Point Sandstone suggests that the Blackhawk-Star Point delta was a high-destructive system. ?? 1979.

Stratigraphy of the Oliocene Sullivan Buttes Latite constrains transition zone development in Chino Valley, Arizona

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, S.A.; Riggs, N.R.

The 26.7--23.4 Ma Sullivan Buttes Latite of Chino Valley, Yavapai County, Arizona, erupted during the development of the Transition Zone between the Basin and Range and Colorado Plateau provinces. Detailed mapping and stratigraphic analysis of a portion of the volcanic field indicate volcanism began with the eruption of a shoshonite lava flow and associated cinder cone. Amphibole latite domes then erupted fallouts, surges, and mass flow breccias and culminated activity with a lava flow. Extrusive units from a biotite oxidized latite center to the east interfinger with the older amphibole lattice volcaniclastics. Sullivan Buttes Latite units erupted onto Precambrian andmore » lower Paleozoic strata and Tertiary gravels; the scarp of upper Paleozoic strata equivalent to the paleo' Mogollon Rim had retreated from the area by the time of emplacement of the oldest Sullivan Buttes Latite unit. Subsequent 15--10 Ma Hickey Formation basalts flowed onto an erosion surface cut into Sullivan Buttes deposits, and the nearby Verde River downcut through younger 4.62 Ma Perkinsville Formation basalt. Both situations demonstrate erosion and degradation post Sullivan Buttes activity. Normal faults offsetting Hickey Formation basalts and all older units constrain Basin and Range structural activity to 15 Ma or younger. These stratigraphic relationships of the Sullivan Buttes Latite in the context of Transition Zone development concur with 65--18 Ma retreat of the upper Paleozoic scarp and below-scarp aggradation, 18--12 Ma Basin and Range faulting, and subsequent degradation.« less

Permian U-Pb (CA-TIMS) zircon ages from Australia and China: Constraining the time scale of environmental and biotic change

NASA Astrophysics Data System (ADS)

Denyszyn, S. W.; Mundil, R.; Metcalfe, I.; He, B.

2010-12-01

In eastern Australia, the interconnected Bowen and Sydney Basins are filled with terrestrial sediments of late Paleozoic to early Mesozoic age. These sedimentary units record significant evolutionary events of eastern Gondwana during the time interval between two major mass extinctions (end Middle Permian and Permian-Triassic), and also provide lithological evidence for the Carboniferous-Permian Late Paleozoic Ice Age of southern Pangea, considered to be divisible into up to seven discrete glaciation events in Australia [e.g., 1]. These glaciations are currently assigned ages that indicate that the last of the glaciations predate the end Middle Permian mass extinction at ca. 260 Ma. However, the estimates for the time and durations are largely based on biostratigraphy and lithostratigraphy that, in the absence of robust and precise radioisotopic ages, are unacceptably fragile for providing an accurate high-resolution framework. Interbedded with the sediments are numerous tuff layers that contain zircon, many of which are associated with extensive coal measures in the Sydney and Bowen Basins. Published SHRIMP U-Pb zircon ages [2, 3] have been shown to be less precise and inaccurate when compared to ages applying the CA-TIMS method to the same horizons. Also within the late Middle Permian, the eruption of the Emeishan flood basalts in SW China has been proposed to have caused the end Middle Permian mass extinction [e.g., 4], though a causal link between these events demands a rigorous test that can only be provided by high-resolution geochronology. We present new U-Pb (CA-TIMS) zircon ages on tuff layers from the Sydney and Bowen Basins, with the purpose of generating a timescale for the Upper Permian of Australia to allow correlation with different parts of the world. Initial results, with permil precision, date a tuff layer within the uppermost Bandanna Fm. to ca. 252 Ma, a tuff within the Moranbah Coal Measures to ca. 256 Ma, and a tuff within the Ingelara Fm. to ca. 257 Ma, the latter two units lying stratigraphically below the latest identified glacial deposits. U-Pb (CA-TIMS) results on zircons from the Emeishan flood basalts and related volcanic products confirm the end-Guadalupian age (ca. 260 Ma) of the magmatism, and based on present data, place the Emeishan volcanic event (and its possibly associated mass extinction) within the occurrence of the Late Paleozoic Ice Age. This study’s primary goal is the establishment of a chronostratigraphic framework that would allow the integration of calibrated records from both terrestrial and marine units from different parts of the world in order to constrain the timing and rates of extinctions and recoveries in different locations and physical environments. [1] Fielding et al. (2008), J. Geol Soc. Lon., v. 165, pp. 129-140 [2] Michaelsen et al. (2001), Aus. J. Earth Sci., v. 48, pp. 183-192 [3] Roberts et al. (1996), Aus. J. Earth Sci., v. 43, pp. 401-421 [4] He et al. (2007), EPSL, v. 255, pp. 306-323

Structurally Altered Hard Coal in the Areas of Tectonic Disturbances - An Initial Attempt at Classification

NASA Astrophysics Data System (ADS)

Godyń, Katarzyna

2016-09-01

As regards the exploitation of hard coal seams, the near-fault zones and faults themselves are considered to be particularly dangerous areas, which is due to a high probability of the occurrence of gasogeodynamic phenomena. Tectonic dislocations running across a seam have a destructive impact on coal. Degradation of the coal structure, particularly visible in the microscale, is reflected in the coal's strength or gas properties. Such "structurally altered" coal is characterized by the presence of numerous fracturings, crushed areas, or dislocations of some of its fragments, and sometimes even the total destruction of the original structure. The present paper provides a detailed analysis and description of near-fault coal obtained from selected seams of the Upper Silesian Coal Basin, completed due to the application of optical methods. Both the type and the degree of changes in the structure of such coal were identified. On this basis, the author attempted to systematize the nomenclature used in relation to selected Upper Silesian hard coal seams, which, in turn, resulted in a proposed classification of the "altered structures" of the near-fault coal.

Age and provenance constraints on seismically-determined crustal layers beneath the Paleozoic southern Central Asian Orogen, Inner Mongolia, China

NASA Astrophysics Data System (ADS)

Jian, Ping; Kröner, Alfred; Shi, Yuruo; Zhang, Wei; Liu, Yaran; Windley, Brian F.; Jahn, Bor-ming; Zhang, Liqao; Liu, Dunyi

2016-06-01

We present 110 ages and 51 in-situ δ18O values for zircon xenocrysts from a post-99 Ma intraplate basaltic rock suite hosted in a subduction-accretion complex of the southern Central Asian Orogenic Belt in order to constrain a seismic profile across the Paleozoic Southern Orogen of Inner Mongolia and the northern margin of the North China Craton. Two zircon populations are recognized, namely a Phanerozoic group of 70 zircons comprising granitoid-derived (ca. 431-99 Ma; n = 31; peak at 256 Ma), meta-granitoid-derived (ca. 449-113 Ma; n = 24; peak at 251 Ma) and gabbro-derived (436-242 Ma; n = 15; peaks at 264 and 244 Ma) grains. Each textural type is characterized by a distinct zircon oxygen isotope composition and is thus endowed with a genetic connotation. The Precambrian population (2605-741 Ma; n = 40) exhibits a prominent age peak at 2520 Ma (granulite-facies metamorphism) and four small peaks at ca. 1900, 1600, and 800 Ma. Our new data, together with literature zircon ages, significantly constrain models of three seismically-determined deep crustal layers beneath the fossil subduction zone-forearc along the active northern margin of the North China Craton, namely: (1) an upper arc crust of early to mid-Paleozoic age, intruded by a major Permian-Triassic composite granitoid-gabbroic pluton (8-20 km depth); (2) a middle crust, predominantly consisting of mid-Meso- to Neoproterozoic felsic and mafic gneisses; and (3) a lower crust composed predominantly of late Archean granulite-facies rocks. We conclude that the Paleozoic orogenic crust is limited to the upper crustal level, and the middle to lower crust has a North China Craton affinity. Furthermore, integrating our data with surface geological, petrological and geochronological constraints, we present a new conceptual model of orogenic uplift, lithospheric delamination and crustal underthrusting for this key ocean-continent convergent margin.

Sedimentary facies of the upper Cambrian (Furongian; Jiangshanian and Sunwaptan) Tunnel City Group, Upper Mississippi Valley: new insight on the old stormy debate

USGS Publications Warehouse

Eoff, Jennifer D.

2014-01-01

New data from detailed measured sections permit a comprehensive revision of the sedimentary facies of the Furongian (upper Cambrian; Jiangshanian and Sunwaptan stages) Tunnel City Group (Lone Rock Formation and Mazomanie Formation) of Wisconsin and Minnesota. Heterogeneous sandstones, comprising seven lithofacies along a depositional transect from shoreface to transitional-offshore environments, record sedimentation in a storm-dominated, shallow-marine epicontinental sea. The origin of glauconite in the Birkmose Member and Reno Member of the Lone Rock Formation was unclear, but its formation and preserved distribution are linked to inferred depositional energy rather than just net sedimentation rate. Flat-pebble conglomerate, abundant in lower Paleozoic strata, was associated with the formation of a condensed section during cratonic flooding. Hummocky cross-stratification was a valuable tool used to infer depositional settings and relative paleobathymetry, and the model describing formation of this bedform is expanded to address flow types dominant during its genesis, in particular the importance of an early unidirectional component of combined flow. The depositional model developed here for the Lone Rock Formation and Mazomanie Formation is broadly applicable to other strata common to the early Paleozoic that document sedimentation along flooded cratonic interiors or shallow shelves.

Lithostratigraphic, conodont, and other faunal links between lower Paleozoic strata in northern and central Alaska and northeastern Russia

USGS Publications Warehouse

Dumoulin, Julie A.; Harris, Anita G.; Gagiev, Mussa; Bradley, Dwight C.; Repetski, John E.

2002-01-01

Lower Paleozoic platform carbonate strata in northern Alaska (parts of the Arctic Alaska, York, and Seward terranes; herein called the North Alaska carbonate platform) and central Alaska (Farewell terrane) share distinctive lithologic and faunal features, and may have formed on a single continental fragment situated between Siberia and Laurentia. Sedimentary successions in northern and central Alaska overlie Late Proterozoic metamorphosed basement; contain Late Proterozoic ooid-rich dolostones, Middle Cambrian outer shelf deposits, and Ordovician, Silurian, and Devonian shallow-water platform facies, and include fossils of both Siberian and Laurentian biotic provinces. The presence in the Alaskan terranes of Siberian forms not seen in wellstudied cratonal margin sequences of western Laurentia implies that the Alaskan rocks were not attached to Laurentia during the early Paleozoic.The Siberian cratonal succession includes Archean basement, Ordovician shallow-water siliciclastic rocks, and Upper Silurian–Devonian evaporites, none of which have counterparts in the Alaskan successions, and contains only a few of the Laurentian conodonts that occur in Alaska. Thus we conclude that the lower Paleozoic platform successions of northern and central Alaska were not part of the Siberian craton during their deposition, but may have formed on a crustal fragment rifted away from Siberia during the Late Proterozoic. The Alaskan strata have more similarities to coeval rocks in some peri-Siberian terranes of northeastern Russia (Kotelny, Chukotka, and Omulevka). Lithologic ties between northern Alaska, the Farewell terrane, and the peri-Siberian terranes diminish after the Middle Devonian, but Siberian afµnities in northern and central Alaskan biotas persist into the late Paleozoic.

Response of carbon isotopic compositions of Early-Middle Permian coals in North China to palaeo-climate change

NASA Astrophysics Data System (ADS)

Ding, Dianshi; Liu, Guijian; Sun, Xiaohui; Sun, Ruoyu

2018-01-01

To investigate the magnitude to which the carbon isotopic ratio (δ13C) varies in coals in response to their contemporary terrestrial environment, the Early-Middle Permian Huainan coals (including coals from the Shanxi Formation, Lower Shihezi Formation and Upper Shihezi Formation) in North China were systematically sampled. A 2.5‰ variation range of δ13C values (-25.15‰ to -22.65‰) was observed in Huainan coals, with an average value of -24.06‰. As coal diagenesis exerts little influence on carbon isotope fractionation, δ13C values in coals were mainly imparted by those of coal-forming flora assemblages which were linked to the contemporary climate. The δ13C values in coals from the Shanxi and Lower Shihezi Formations are variable, reflecting unstable climatic oscillations. Heavy carbon isotope is enriched in coals of the Capitanian Upper Shihezi Formation, implying a shift to high positive δ13C values of coeval atmospheric CO2. Notably, our study provides evidence of the Kamura event in the terrestrial environment for the first time.

Arsenic in rocks and stream sediments of the central Appalachian Basin, Kentucky

USGS Publications Warehouse

Tuttle, Michele L.W.; Goldhaber, Martin B.; Ruppert, Leslie F.; Hower, James C.

2002-01-01

Arsenic (As) enrichment in coal and stream sediments has been documented in the southern Appalachian basin (see Goldhaber and others, submitted) and is attributed to interaction of rocks and coal with metamorphic fluids generated during the Allegheny Orogeny (late Paleozoic). Similarly derived fluids are expected to affect the coal and in the Kentucky Appalachian Basin to the north as well. In addition, similar processes may have influenced the Devonian oil shale on the western margin of the basin. The major goals of this study are to determine the effect such fluids had on rocks in the Kentucky Appalachian basin (fig. 1), and to understand the geochemical processes that control trace-metal source, residence, and mobility within the basin. This report includes data presented in a poster at the USGS workshop on arsenic (February 21 and 22, 2001), new NURE stream sediment data3 , and field data from a trip in April 2001. Although data for major and minor elements and all detectable trace metals are reported in the Appendices, the narrative of this report primarily focuses on arsenic.

Hardgrove grindability study of Powder River Basin and Appalachian coal components in the blend to a midwestern power station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padgett, P.L.; Hower, J.C.

1996-12-31

Five coals representing four distinct coal sources blended at a midwestern power station were subjected to detailed analysis of their Hardgrove grindability. The coals are: a low-sulfur, high volatile A bituminous Upper Elkhorn No. 3 coal (Pike County, KY); a medium-sulfur, high volatile A bituminous Pittsburgh coal (southwestern PA); a low-sulfur, subbituminous Wyodak coal from two mines in the eastern Powder River Basin (Campbell County, WY). The feed and all samples processed in the Hardgrove grindability test procedure were analyzed for their maceral and microlithotype content. The high-vitrinite Pittsburgh coal and the relatively more petrographically complex Upper Elkhorn No. 3more » coal exhibit differing behavior in grindability. The Pittsburgh raw feed, 16x30 mesh fraction (HGI test fraction), and the {minus}30 mesh fraction (HGI reject) are relatively similar petrographically, suggesting that the HGI test fraction is reasonably representative of the whole feed. The eastern Kentucky coal is not as representative of the whole feed, the HGI test fraction having lower vitrinite than the rejected {minus}30 mesh fraction. The Powder River Basin coals are high vitrinite and show behavior similar to the Pittsburgh coal.« less

12. Interior, boiler house, at elev. 55' looking west at ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Interior, boiler house, at elev. 55' looking west at retired 300 lb. boilers #11, 10, and 9 with pulverized coal storage hoppers on upper left and rock coal storage bunkers on upper right. - Manchester Street Generating Station, Manchester Street Station, 460 Eddy Street, Providence, Providence County, RI

Depositional history of the Fire Clay coal bed (Late Duckmantian), Eastern Kentucky, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Hower, J.C.

1999-01-01

More than 3800 coal thickness measurements, proximate analyses from 97 localities, and stratigraphic and sedimentological analyses from more than 300 outcrops and cores were used in conjunction with previously reported palynological and petrographic studies to map individual benches of the coal and document bench-scale variability in the Fire Clay (Hazard No. 4) coal bed across a 1860 km2 area of the Eastern Kentucky Coal Field. The bench architecture of the Fire Clay coal bed consists of uncommon leader benches, a persistent but variable lower bench, a widespread, and generally thick upper bench, and local, variable rider benches. Rheotrophic conditions are inferred for the leader benches and lower bench based on sedimentological associations, mixed palynomorph assemblages, locally common cannel coal layers, and generally high ash yields. The lower bench consistently exhibits vertical variability in petrography and palynology that reflects changing trophic conditions as topographic depressions infilled. Infilling also led to unconfined flooding and ultimately the drowning of the lower bench mire. The drowned mire was covered by an air-fall volcanic-ash deposit, which produced the characteristic flint clay parting. The extent and uniform thickness of the parting suggests that the ash layer was deposited in water on a relatively flat surface without a thick canopy or extensive standing vegetation across most of the study area. Ash deposits led to regional ponding and establishment of a second planar mire. Because the topography had become a broadly uniform, nutrient-rich surface, upper-bench peats became widespread with large areas of the mire distant to clastic sources. Vertical sections of thick (> 70 cm), low-ash yield, upper coal bench show a common palynomorph change from arborescent lycopod dominance upward to fern and densospore-producing, small lycopod dominance, inferred as a shift from planar to ombrotrophic mire phases. Domed mires appear to have been surrounded by wide areas of planar mires, where the coal was thinner (< 70 cm), higher in ash yield, and dominated by arborescent lycopods. Rectangular thickness trends suggest that syndepositional faulting influenced peat accumulation, and possibly the position of the domed mire phase. Faulting also influenced post-depositional clastic environments of deposition, resulting in sandstone channels with angular changes in orientation. Channels and lateral facies were locally draped by high-ash-yield rider coal benches, which sometimes merged with the upper coal bench. These arborescent-lycopod dominant rider coal benches were profoundly controlled by palcotopography, much like the leader coal benches. Each of the benches of coal documented here represent distinctly different mires that came together to form the Fire Clay coal bed, rather than a single mire periodically split by clastic influx. This is significant as each bench of the coal has its own characteristics, which contribute to the total coal characteristics. The large data set allows interpretation of both vertical and lateral limits to postulated domed phases in the upper coal bench, and to the delineation of subtle tectonic structures that allow for meaningful thickness projections beyond the limits of present mining.A study was conducted to analyze the depositional history of the Fire Clay coal bed in the eastern Kentucky coal field. The study involved over 3800 coal thickness measurements, proximate analyses from 97 localities, and stratigraphic and sedimentological analyses from more than 300 outcrops and cores in conjunction with previously reported palynological and petrographic studies to map individual benches of the coal and document bench-scale variability.

Coal resources of the Fruitland Formation in part of the Ute Mountain Ute Indian Reservation, San Juan County, New Mexico

USGS Publications Warehouse

Roberts, Laura N. Robinson

1991-01-01

The coal-bearing Upper Cretaceous Fruitland Formation occupies an area of about 14 square miles in the extreme southeast corner of the Ute Mountain Ute Indian Reservation in San Juan County, New Mexico. In this area, the Fruitland Formation contains an estimated 252 million short tons of coal in beds that range from 1.2 to 14 feet thick. About 100 million short tons of coal occur under less than 500 feet of overburden in the Ute Canyon, Upper Main, and Main coal beds. These three coal beds reach a cumulative coal thickness of about 18 feet in a stratigraphic interval that averages about 120 feet thick in the prospecting permit area, which is located in the extreme southwestern part of the study area. The southwestern part of the study area is probably best suited for surface mining, although steep dips may reduce minability locally. A major haul road that was recently constructed across the eastern half of the study area greatly improves the potential for surface mining. Core sample analyses indicate that the apparent rank of the Ute Canyon, Upper Main, and Main coal beds is high-volatile C bituminous. Average heat-of-combustion on an as-received basis is 10,250 British thermal units per pound, average ash content is 15.5 percent, and average sulfur content is 1.0 percent.

Power from Coal. A Student Handbook Recommended for Upper Elementary and Middle Grades.

ERIC Educational Resources Information Center

National Coal Association, Washington, DC.

The contributions of coal as an important energy source are reviewed in this booklet for teachers. It provides background information on coal, activities for classroom use, and an answer key for all the exercises. The introductory section includes information on: (1) coal and electricity; (2) reasons for using coal; (3) methods for extracting…

Assessment of Paleozoic terrane accretion along the southern central Andes using detrital zircon geochronology

NASA Astrophysics Data System (ADS)

McKenzie, R.; Horton, B. K.; Fuentes, F.; Fosdick, J. C.; Capaldi, T.; Stockli, D. F.; Alvarado, P. M.

2015-12-01

Two distinct Paleozoic terranes known as Cuyania and Chilenia occupy the southern central Andes of Argentina and Chile. Because the proposed terrane boundaries coincide with major structural elements of the modern Andean system at 30-36°S, it is important to understand their origins and potential role in guiding later Andean deformation. The Cuyania terrane of western Argentina encompasses the Precordillera (PC) and a thick-skinned thrust block of the western Sierras Pampeanas, persisting southward to the San Rafael Basin (SRB). Although recently challenged, Cuyania has been long considered a piece of southern Laurentia that rifted away during the early Cambrian and collided with the Argentine margin during the Ordovician. Chilenia is situated west of Cuyania and includes the Frontal Cordillera (FC) and Andean magmatic arc. This less-studied terrane was potentially accreted during an enigmatic Devonian orogenic event. We present new detrital zircon U-Pb age data from siliciclastic sedimentary rocks that span the entire Paleozoic to Triassic from the FC, PC, and SRB. Cambrian rocks of the PC exhibit similar zircon age distributions with prominent ~1.4 and subordinate ~1.1 Ga populations, which are distinct from other Paleozoic strata. Plutonic rocks with these ages are common in southern Laurentia, whereas ~1.4 Ga zircons are uncommon in South American age distributions. This supports a Laurentian origin for Cuyania in isolation from Argentina during the Cambrian. Upper Paleozoic strata from the PC, FC, and SRB all yield similar age data suggesting shared provenance across the proposed Cuyania-Chilenia suture. Age distributions also notably lack Devonian-age grains. The regional paucity of Devonian plutonic rocks and detrital zircon casts doubt on a possible arc system between these terranes at this time, a key requisite for the mid-Paleozoic transfer and accretion of Chilenia to the Argentine margin. Collectively, these data question the precise boundaries of the Chilenia terrane.

Intracratonic exhumation and uplift: Insight from low-temperature thermochronology and geomorphic analysis of the Ozark Plateau, Missouri

NASA Astrophysics Data System (ADS)

DeLucia, M. S.; Marshak, S.; Guenthner, W.; Anders, A. M.; Thomson, S. N.

2016-12-01

The Ozark Plateau is an uplift in the cratonic platform of Midcontinent United States. In the northeast corner of the plateau (the St. Francois Mountains), Precambrian basement of 1.47 Ga granite and rhyolite crops out. These rocks are overlain, at the Great Unconformity, by Paleozoic strata, defining the map pattern of the Ozark Dome. Strata thicken substantially eastward into the Illinois Basin, so that there is over 7 km of structural relief across the boundary between the Illinois Basin and the Ozark Dome at the level of the Great Unconformity. Multiple unconformities in the Paleozoic section indicates that the crest of the Ozark Dome was at or above sea level several times during the Paleozoic. Key questions about the Plateau remain. For example: (1) Did the 1.47 Ga basement remain at upper-crustal depths since its formation, or was it buried deeply and later exhumed? (2) Has the plateau remained high since the Paleozoic or has it undergone post-Paleozoic uplift? Results from new zircon (U-Th)/He thermochronology indicate that the 1.47 Ga granites were exhumed significantly in the Neoproterozoic (about 750Ma), after the Rodinia supercontinent assembly. Fission-track dates (Brown, 2005) and (U-Th)/He apatite dates (Flowers and Kelley, 2011; Zhang et al., 2012; and new results) hint that some post-Paleozoic exhumation has occurred. Analysis of a high-resolution DEM of the Ozark Plateau supports this proposal; bedrock-incising streams occur throughout the plateau (locally producing incised meanders), and strath terraces can be identified. The rate of uplift, however, must be relatively slow, for drainages do not display knick points, and drainage networks display mature profiles. Given these constraints, we propose that the lithospheric architecture that distinguished the Ozark Dome from the Illinois Basin became established in the Neoproterozoic, and that the Ozark Plateau has been maintained isostatically by subsequent slow exhumation.

Palynologic and petrographic intervals in the upper Pennsylvanian McLeansboro Group, Western Kentucky

USGS Publications Warehouse

Hower, J.C.; Helfrich, C.T.; Williams, D.A.

1994-01-01

The McLeansboro Group (formerly the Sturgis Formation) in the Western Kentucky coal field spans the upper Desmoinesian (Westphalian D) and the Missourian and Virgilian series (Stephanian). Extensive drilling has demonstrated the lateral continuity of major and minor beds in the group, making it possible to study vertical and lateral changes in palynology and petrology. Significant features of the McLeansboro Group are the marine zones over most of the coals and paleochannels, which are the only disruptions to the continuity of other lithologies. The Desmoinesian Baker (No. 13) and Wheatcroft (No. 13a) coal beds were included in the study but the primary emphasis is on the Missourian and Virgilian coals. Patoka Formation (lower Missourian) coals are dominated by tree fern spores with lesser amounts of sphenopsids, ferns and cordaites spores. This is in marked contrast to the arborescent lycopod-dominated Desmoinesian coals. Only the No. 15 coal bed exceeds 80% vitrinite: the vitrinite content of the No. 16 coal bed is less than 72%, the lowest of any Western Kentucky humic coal. The Bond Formation (upper Missourian) represents a distinct floristic interval, with a greater diversity of plant groups than in the Patoka Formation. Herbaceous lycopod spores, which are relatively minor contributors to the Patoka coals, are common in the Bond Formation. The coals generally exceed 80% vitrinite. The Mattoon Formation (Virgillian) coals have a variety of palynomorph assemblages. The low-sulfur Geiger Lake coal bed is dominated by tree fern spores, with important contributions from other ferns and sphenopsids. Similar to the underlying tree fern interval, vitrinite contents are less than 80%. The uppermost Mattoon coals are dominated by tree ferns and are notable in being the only coals more than 1 m thick in the Stephanian portion of the section, with the top coal being 4.3 m thick. The uppermost coals generally contain more than 80% vitrinite. The Permian Mauzy Formation overlies the McLeansboro Group. The palynologic/petrographic intervals appear to represent fluctuating dry (low vitrinite) and wet intervals within the Stephanian, which was itself drier than the Westphalian D. ?? 1994.

Stratigraphy of lower to middle Paleozoic rocks of northern Nevada and the Antler orogeny

USGS Publications Warehouse

Ketner, Keith B.

2013-01-01

Commonly accepted concepts concerning the lower Paleozoic stratigraphy of northern Nevada are based on the assumption that the deep-water aspects of Ordovician to Devonian siliceous strata are due to their origin in a distant oceanic environment, and their presence where we find them is due to tectonic emplacement by the Roberts Mountains thrust. The concept adopted here is based on the assumption that their deep-water aspects are the result of sea-level rise in the Cambrian, and all of the Paleozoic strata in northern Nevada are indigenous to that area. The lower part of the Cambrian consists mainly of shallow-water cross-bedded sands derived from the craton. The upper part of the Cambrian, and part of the Ordovician, consists mainly of deep-water carbonate clastics carried by turbidity currents from the carbonate shelf in eastern Nevada, newly constructed as a result of sea-level rise. Ordovician to mid-Devonian strata are relatively deep-water siliceous deposits, which are the western facies assemblage. The basal contact of this assemblage on autochthonous Cambrian rocks is exposed in three mountain ranges and is clearly depositional in all three. The western facies assemblage can be divided into distinct stratigraphic units of regional extent. Many stratigraphic details can be explained simply by known changes in sea level. Upper Devonian to Mississippian strata are locally and westerly derived orogenic clastic beds deposited disconformably on the western facies assemblage. This disconformity, clearly exposed in 10 mountain ranges, indicates regional uplift and erosion of the western facies assemblage and absence of local deformation. The disconformity represents the Antler orogeny.

Upper Cretaceous bituminous coal deposits of the Olmos Formation, Maverick County, Texas

USGS Publications Warehouse

Hook, Robert W.; Warwick, Peter D.; SanFilipo, John R.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

2011-01-01

This report describes the bituminous coal deposits of the Olmos Formation (Navarro Group, Upper Cretaceous; Figures 1, 2) of Maverick County in south Texas. Although these were not evaluated quantitatively as part of the current Gulf Coastal Plain coal-resource assessment, a detailed review is presented in this chapter.Prior to the late 1920s, these coal beds were mined underground on a large scale in the vicinity of Eagle Pass, Texas (Figure 1). Since the 1970s, Olmos Formation coals have been mined extensively in both underground and surface mines in nearby Coahuila, Mexico, to supply mine-mouth fuel for power generation at a plant nearby. A tract northeast of Eagle Pass was permitted in the late 1990s for surface mining. In east-central Maverick County, a coalbed methane field is being developed in coal beds of the lower part of the Olmos Formation (Barker et al., 2002; Scott, 2003).

Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

USGS Publications Warehouse

Zodrow, E.L.; Lyons, P.C.; Millay, M.A.

1996-01-01

The 11-13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81-100%), dolomite-ankerite (0-19%), minor quartz and illite, and trace amounts of 'calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

Results of coal bed methane drilling, Mylan Park, Monongalia County, West Virginia

USGS Publications Warehouse

Ruppert, Leslie F.; Fedorko, Nick; Warwick, Peter D.; Grady, William C.; Crangle, Robert D.; Britton, James Q.

2004-01-01

The Department of Energy National Energy Technology Laboratory funded drilling of a borehole (39.64378 deg E , -80.04376 deg N) to evaluate the potential for coal bed methane and carbon dioxide sequestration at Mylan Park, Monongalia County, West Virginia. The drilling commenced on September 23, 2002 and was completed on November 14, 2002. The 2,525 ft deep hole contained 1,483.41 ft of Pennsylvanian coal-bearing strata, 739.67 feet of Mississippian strata, and 301.93 ft. of Devonian strata. The drill site was located directly over abandoned Pittsburgh and Sewickley coal mines. Coal cores from remaining mine pillars were cut and retrieved for desorption from both mines. In addition, coals were cored and desorbed from the Pittsburgh Roof, Little Pittsburgh, Elk Lick, Brush Creek, Upper Kittanning, Middle Kittanning, Clarion, Upper Mercer, Lower Mercer, and Quakertown coal beds. All coals are Pennsylvanian in age and are high-volatile-A bituminous in rank. A total of 34.75 ft of coal was desorbed over a maximum period of 662 days, although most of the coal was desorbed for about 275 days. This report is provided in Adobe Acrobat format. Appendix 3 is provided in Excel format.

Correlation of coal beds, coal zones, and key stratigraphic units in the Pennsylvanian rocks of eastern Kentucky

USGS Publications Warehouse

Rice, Charles L.; Smith, J. Hiram

1980-01-01

The Pennsylvanian rocks of the eastern Kentucky coal field unlderlie an area of about 27,000 square kilometers (see index map). Largely because of the size and stratigraphic complexity of the area, Huddle and others (1963, p. 31) divided it into six coal reserve districts (unofficial), utilizing state and county lines as well as geologic features, drainage areas, and cola producing areas. This division is followed herein because, in general, each of these districts has a characteristic stratigraphic nomenclature, particularly as related to coal bed names. The six districts shown on the index mat, are the Princess, Licking River, Big Sandy, Hazard, Southwestern, and Upper Cumberland River; the Upper Cumberland River district has been divided into the Harlan and Middlesboro subdistricts. 

The Cottage Grove fault system (Illinois Basin): Late Paleozoic transpression along a Precambrian crustal boundary

USGS Publications Warehouse

Duchek, A.B.; McBride, J.H.; Nelson, W.J.; Leetaru, H.E.

2004-01-01

The Cottage Grove fault system in southern Illinois has long been interpreted as an intracratonic dextral strike-slip fault system. We investigated its structural geometry and kinematics in detail using (1) outcrop data, (2) extensive exposures in underground coal mines, (3) abundant borehole data, and (4) a network of industry seismic reflection profiles, including data reprocessed by us. Structural contour mapping delineates distinct monoclines, broad anticlines, and synclines that express Paleozoic-age deformation associated with strike slip along the fault system. As shown on seismic reflection profiles, prominent near-vertical faults that cut the entire Paleozoic section and basement-cover contact branch upward into outward-splaying, high-angle reverse faults. The master fault, sinuous along strike, is characterized along its length by an elongate anticline, ???3 km wide, that parallels the southern side of the master fault. These features signify that the overall kinematic regime was transpressional. Due to the absence of suitable piercing points, the amount of slip cannot be measured, but is constrained at less than 300 m near the ground surface. The Cottage Grove fault system apparently follows a Precambrian terrane boundary, as suggested by magnetic intensity data, the distribution of ultramafic igneous intrusions, and patterns of earthquake activity. The fault system was primarily active during the Alleghanian orogeny of Late Pennsylvanian and Early Permian time, when ultramatic igneous magma intruded along en echelon tensional fractures. ?? 2004 Geological Society of America.

Geomagnetic Reversals during the Phanerozoic.

PubMed

McElhinny, M W

1971-04-09

An antalysis of worldwide paleomagnetic measurements suggests a periodicity of 350 x 10(6) years in the polarity of the geomagnetic field. During the Mesozoic it is predominantly normal, whereas during the Upper Paleozoic it is predominantly reversed. Although geomagnetic reversals occur at different rates throughout the Phanerozoic, there appeaars to be no clear correlation between biological evolutionary rates and reversal frequency.

Hydromechanical Advanced Coal Excavator

NASA Technical Reports Server (NTRS)

Estus, Jay M.; Summers, David

1990-01-01

Water-jet cutting reduces coal dust and its hazards. Advanced mining system utilizes full-face, hydromechanical, continuous miner. Coal excavator uses high-pressure water-jet lances, one in each of cutting heads and one in movable lance, to make cuts across top, bottom and middle height, respectively, of coal face. Wedge-shaped cutting heads advance into lower and upper cuts in turn, thereby breaking coal toward middle cut. Thrust cylinders and walking pads advance excavator toward coal face.

Paleoenvironmental model for the occurrence of vertebrate fossils in Carboniferous coal-bearing strata

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hook, R.W.

An interdisciplinary investigation was undertaken to identify the paleoenvironmental factors that governed the accumulation and preservation of a prolific Upper Carboniferous vertebrate assemblage known from a cannel coal underlying the Upper Freeport coal in the Diamond Coal Mine of Linton, Ohio. Stratigraphic data from previous work and field studies within an approximately 15 km radius of the fossil locality show that the channel occupies a 10 km long, north-northwest trending abandoned channel that occurs within a sandstone-dominated, fining-upwards fluvial sequence. Petrographic analysis of samples from eight sites along the course of the abandoned channel establishes that the cannel is composedmore » primarily of spores and very fine-grained micrinitic groundmass. Abundant primary pyrite and the absence of well-reserved humic materials suggest that the fossiliferous cannel originated as a sapropelic peat within a non-acidic anaerobic environment. Skeletal remains of animals are well preserved with little to no mineralogic alteration. Outside the abandoned channel in the Linton area and to the north, Upper Freeport coal averages 1 m in thickness. To the south, the Upper Freeport horizon is represented by interbedded flint clays and freshwater limestones. These sediment distribution patterns reflect the synsedimentary influence of the Transylvania Fault Zone, a previously documented, basement-controlled feature which trends east-west through the study area. Contemporaneous movement along this fault produced a topographic high in the Linton area which was locally entrenched by northward-flowing rivers. Upper Freeport swamps developed on this upthrown surface whereas carbonate lakes formed to the south of the fault zone in topographically lower areas.« less

21. PHOTOGRAPH OF PAGE 986 IN Keystone Coal Buyers Catalog, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. PHOTOGRAPH OF PAGE 986 IN Keystone Coal Buyers Catalog, 1922, UPPER PHOTOGRAPH, VIEW SOUTH, COMMUNITY OF ETHEL; ETHEL COAL COMPANY MINE SUPPLY BUILDING IS LOCATED IN MID-GROUND LEFT OF CENTER PARTIALLY OBSCURED BY ROOF OF HOUSE IN FOREGROUND - Ethel Coal Company & Supply Building, Left fork of Dingess Run (Ethel Hollow), Ethel, Logan County, WV

An unusual occurrence of arsenic-bearing pyrite in the Upper Freeport coal bed, West-Central Pennsylvania

USGS Publications Warehouse

Ruppert, L.F.; Minkin, J.A.; McGee, J.J.; Cecil, C.B.

1992-01-01

Scanning electron microscopy and electron microprobe analysis were used to identify a rare type of As-bearing pyrite in selected specific gravity separates from the Pennsylvanian age Upper Freeport coal bed, west-central Pennsylvania. Arsenic was detected mainly in cell-wall replacement pyrite where concentrations ranged from nondetectable to 1.9 wt %. Although the majority of arsenic-bearing pyrite in the Upper Freeport coal bed is concentrated in massive and late diagenetic pyrite morphologies, the rarer As-bearing cell-replacement pyrite was observed in both light and heavy gravity separates from the three coal facies examined. Arsenic was occasionally detected in cell-filling replacement pyrite, but this As appears to be an artifact produced by signals from underlying and/or adjacent As-bearing cell-wall replacement pyrite. It is postulated that some plants of the Upper Freeport paleoswamp may have biomethylated As, which later could have been converted to dimethylarsine or other volatile organoarsenic compounds by either biologically or chemically driven processes. Once liberated, the arsenic may have been incorporated into pyrite during pyritization of the cell walls. The As incorporation occurred early, before significant compaction of the peat, because the pyritized cell walls are not compacted.

Chemometric Study of Trace Elements in Hard Coals of the Upper Silesian Coal Basin, Poland

PubMed Central

Rompalski, Przemysław; Cybulski, Krzysztof; Chećko, Jarosław

2014-01-01

The objective of the study was the analysis of trace elements contents in coals of the Upper Silesian Coal Basin (USCB), which may pose a potential threat to the environment when emitted from coal processing systems. Productive carbon overburden in central and southern zones of the USCB is composed mostly of insulating tertiary formations of a thickness from a few m to 1,100 m, and is represented by Miocene and Pliocene formations. In the data study the geological conditions of the coal seams of particular zones of the USCB were taken into account and the hierarchical clustering analysis was applied, which enabled the exploration of the dissimilarities between coal samples of various zones of the USCB in terms of basic physical and chemical parameters and trace elements contents. Coals of the northern and eastern zones of the USCB are characterized by high average Hg and low average Ba, Cr, and Ni contents, whereas coals of southern and western zones are unique due to high average concentrations of Ba, Co, Cu, Ni, and V. Coals of the central part of the USCB are characterized by the highest average concentration of Mn and the lowest average concentrations of As, Cd, Pb, V, and Zn. PMID:24967424

Tectonics of the North American Cordillera near the Fortieth Parallel

USGS Publications Warehouse

King, P.B.

1978-01-01

The North American Cordillera near the Fortieth Parallel consists of the following tectonic units: 1. (A) To the east is a reactivated cratonic area, in the Southern Rocky Mountains and Colorado Plateau, in which the supracrustal rocks (Cambrian to Cretaceous) were broadly deformed during the late Cretaceous-Paleocene Laramide orogeny, and the Precambrian basement was raised in folds of wide amplitude. 2. (B) West of it is a miogeosynclinal belt, in the eastern Great Basin, in which a thick sequence of Paleozoic carbonates and related deposits was thrust eastward along low-angle faults during the middle to late Cretaceous Sevier orogeny. The miogeosyncline is the downwarped western margin of the original North American continent, and its rocks accumulated on Precambrian basement. 3. (C) Beyond is a eugeosynclinal belt, in the western Great Basin, in which Paleozoic graywackes, cherts, and volcanics were thrust easteastward along low-angle faults during several Paleozoic orogenies - the mid-Paleozoic Antler orogeny which produced the Roberts thrust on the east, and the end-Paleozoic Sonoma orogeny which produced the Golconda thrust farther west. The Paleozoic eugeosynclinal rocks accumulated on oceanic basement. They are overlapped from the west by Triassic and Jurassic shelf deposits, which pass westward into eugeosynclinal deposits. 4. (D) A volcanic island-arc belt existed on the sites of the Sierra Nevada in Paleozoic and early Mesozoic time, which produced thick bodies of sediments and volcanics. During the mid-Mesozoic Nevadan orogeny these were steeply deformed and thrust westward over subduction zones, and were intruded by granitic rocks that rose from the upper mantle to form great batholiths. 5. (E) West of the Sierra Nevada, in the Great Valley, is a great sedimentary embankment of later Mesozoic flysch or turbidite, largely younger than the supracrustal rocks of the Sierra Nevada and the Nevadan orogeny. It was formed of the erosional products of the supracrustal and granitic rocks of the Sierra Nevada. 6. (F) This sequence is, in turn, thrust westward over the Mesozoic Franciscan terrane of the Coast Ranges, which forms the westernmost belt of the Cordillera, and which is being treated in other papers in this symposium. The net effect of the prolonged events that produced the Cordillera in this segment has been the addition of successive tectonic belts to the North American continent at the expense of the Pacific Ocean basin during Phanerozoic time. ?? 1978.

The evolutionary diversification of seed size: using the past to understand the present.

PubMed

Sims, Hallie J

2012-05-01

The Devonian origin of seed plants and subsequent morphological diversification of seeds during the late Paleozoic represents an adaptive radiation into unoccupied ecological niche space. A plant's seed size is correlated with its life-history strategy, growth form, and seed dispersal syndrome. The fossil record indicates that the oldest seed plants had relatively small seeds, but the Mississippian seed size envelope increased significantly with the diversification of larger seeded lineages. Fossil seeds equivalent to the largest extant gymnosperm seeds appeared by the Pennsylvanian, concurrent with morphological diversification of growth forms and dispersal syndromes as well as the clade's radiation into new environments. Wang's Analysis of Skewness indicates that the evolutionary trend of increasing seed size resulted from primarily passive processes in Pennsylvanian seed plants. The distributions of modern angiosperms indicate a more diverse system of active and some passive processes, unbounded by Paleozoic limits; multiple angiosperm lineages independently evolved though the upper and lower bounds. Quantitative measures of preservation suggest that, although our knowledge of Paleozoic seeds is far from complete, the evolutionary trend in seed size is unlikely to be an artifact of taphonomy. © 2012 The Author. Evolution© 2012 The Society for the Study of Evolution.

Petroleum geology of the major producing basins of Algeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Attar, A.; Chaouch, A.

1988-08-01

The South Atlas flexure divides Algeria into two contrasting geologic provinces: (1) the Saharan Atlas and offshore region in the north, both of which are part of the Mediterranean basin, and (2) the Saharan platform on the south, part of the North African craton. The limits of the various sedimentary basins on the Saharan platform are tied to late Paleozoic (Hercynian) crustal reactivation. Comparable structurally controlled basins in northern Algeria are the products of Mesozoic-Recent tectonism. The spatial and temporal distribution of hydrocarbons in the Algerian Sahara can be understood in terms of the geologic evolution of the region. Analysismore » of areas of proven hydrocarbon reserves permits the following generalizations. (1) There is a concentration of oil and gas fields northeast of a northwest-southeast-trending line connecting Hassi R'Mel with In Amenas. Production is also established in the Sbaa basin and in northern Algeria, where recent discoveries have been made in, respectively, upper Paleozoic and Mesozoic reservoirs. (2) Hydrocarbon are present throughout the entire sedimentary column, but major production currently is restricted to the lower Paleozoic (Cambrian-Ordovician and Lower Devonian) and Triassic reservoirs.« less

The Juchatengo complex: an upper-level ophiolite assemblage of late Paleozoic age in Oaxaca, southern Mexico

NASA Astrophysics Data System (ADS)

Grajales-Nishimura, José Manuel; Ramos-Arias, Mario Alfredo; Solari, Luigi; Murillo-Muñetón, Gustavo; Centeno-García, Elena; Schaaf, Peter; Torres-Vargas, Ricardo

2018-04-01

The Juchatengo complex (JC) suite is located between the Proterozoic Oaxacan complex to the north and the Xolapa complex to the south, and was amalgamated by late Paleozoic magmatism. It consists of mafic and sedimentary rocks that have oceanic affinities, with internal pseudostratigraphic, structural and metamorphic characteristics, which resemble a typical upper-level ophiolite assemblage. New U-Pb zircon and previous hornblende K-Ar analyses yield ages of ca. 291-313 Ma (U-Pb) for plagiogranites and ca. 282-277 Ma for tonalites intruding the entire sequence, including pelagic sediments at the top, with a maximum deposition age of ca. 278 Ma and noteworthy local provenance. These data constrain the age of the JC to the Late Pennsylvanian-Early Permian period. Hf isotopic analyses obtained from zircons in the JC plagiogranite and tonalite show that they come from a similar primitive mantle source (176Hf/177Hf: 0.282539-0.283091; ƐHf(t): + 3.2 to + 15.0). ƐHf(t) values from near 0 to - 2.8 in the tonalites indicate a contribution from the continental crust. Trace elements and REE patterns in whole rock and zircons point to a primitive mantle source for differentiated mafic, plagiogranite dykes and tonalitic plutons. Geochronological and geochemical data address the generation of new oceanic crust above the subduction zone, probably in a backarc setting. In this tectonic scenario, the JC ophiolite originated due to the convergence of the paleo-Pacific plate below the already integrated Oaxacan and Acatlán complexes in western Pangea. The dextral displacement places the deformation in a transtensional regime during the late Paleozoic age.

Paleobotany and palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian)

USGS Publications Warehouse

Willard, D.A.; Phillips, T.L.

1993-01-01

Late Pennsylvanian coal swamps of the Illinois Basin were dominated by Psarnius tree ferns with a spatially heterogeneous distribution of medullosan pteridosperms (subdominant), calamites, sigillarian lycopsids, and cordaites. Miospore and coal-ball plant assemblages from the Missourian-age Bristol Hill Coal Member (Mattoon Formation) of southeastern Illinois were quantified to analyze vegetational patterns in Late Pennsylvanian peat swamps and to compare vegetational composition of the coals. -from Authors

Aromatized arborane/fernane hydrocarbons as molecular indicators of floral changes in Upper Carboniferous/Lower Permian strata of the Saar-Nahe Basin, southwestern Germany

NASA Astrophysics Data System (ADS)

Vliex, M.; Hagemann, H. W.; Püttmann, W.

1994-11-01

Thirty-seven coal samples of Upper Carboniferous and Lower Permian age from three boreholes in the Saar-Nahe Basin, Germany, have been studied by organic geochemical and coal petrological methods. The investigations were aimed at the recognition of floral changes in the Upper Carboniferous and Lower Permian strata. The results show that compositional changes in the extracts are only partly caused by variations in coalification. Specific aromatic hydrocarbons appear in Upper Westphalian D coal seams and increase in concentration up to the Rotliegendes. The dominant compound has been identified by mass spectrometry and NMR-spectroscopy as 5-methyl-10-(4-methylpentyl)-des- A-25-norarbora(ferna)-5,7,9-triene (MATH) and always occurs associated with 25-norarbora(ferna)-5,7,9-triene. Both compounds are thought to originate from isoarborinol, fernene-3β-ol, or fernenes. The strongly acidic conditions during deposition of the coals might have induced the 4,5-cleavage combined with a methyl-shift in an arborane/fernane-type pentacyclic precursor yielding the MATH. Based on petrological investigations, palynomorphs related to early Gymnospermopsida such as Pteridospermales and Coniferophytes ( Cordaitales and Coniferales) increased in abundance in the strata beginning with the Upper Westphalian D concomitant with the above mentioned biomarkers. The results suggest the arborane/fernane derivatives originate from the plant communities producing these palynomorphs.

Hydrogeology and preliminary assessment of regional flow in the upper Cretaceous and adjacent aquifers in the northern Mississippi embayment

USGS Publications Warehouse

Brahana, J.V.; Mesko, T.O.

1988-01-01

On a regional scale, the groundwater system of the northern Mississippi embayment is composed of a series of nonindurated clastic sediments that overlie a thick sequence of Paleozoic carbonate, sandstones, and shales. The units that comprise the geohydrologic framework of this study are the alluvium-lower Wilcox Aquifer the Midway confining unit, the Upper Cretaceous aquifer, the Cretaceous-Paleozoic confining unit, and the Ozark-St. Francois aquifer. The Upper Cretaceous aquifer of Late Cretaceous age is the primary focus of this investigation; the study is part of the Gulf Coast Regional Aquifer-System Analysis. A four layer finite-difference groundwater flow model enabled testing of alternative boundary concepts and provide a refined definition of the hydrologic budget of the deep aquifers. The alluvium-lower Wilcox aquifer, the Upper Cretaceous aquifer, and the Ozark-St. Francois aquifer form layers 2 through 4, respectively. Layer 1 is an inactive layer of constant heads representing shallow water levels, which are a major control on recharge to and discharge from the regional system. A matrix of leakance values simulates each confining unit, allowing vertical interchange of water between different aquifers. The model was calibrated to 1980 conditions by using the assumption that 1980 was near steady-state conditions; it was calibrated to simulate observed heads were found to be most sensitive to pumping, and least sensitive to the leakance. By using all available water quality and water level data, alternative boundary conditions were tested by comparing model simulated heads to observed heads. The results of the early modeling effort also contribute to a better understanding of the regional hydrologic budget, indicating that: upward leakage from the Ozark-St. Francois aquifer to the Upper Cretaceous aquifer is about 43 cu ft/sec; upward recharge of about 68 cu ft/sec occurs to the lower Wilcox-alluvium aquifer from the Upper Cretaceous aquifer; and the Midway is an effective regional confining unit. (Author 's abstract)

MICROCHARACTERIZATION OF ARSENIC- AND SELENIUM-BEARING PYRITE IN UPPER FREEPORT COAL, INDIANA COUNTY, PENNSYLVANIA.

USGS Publications Warehouse

Minkin, J.A.; Finkelman, R.B.; Thompson, C.L.; Chao, E.C.T.; Ruppert, L.F.; Blank, H.; Cecil, C.B.

1984-01-01

Optical and scanning electron microscope as well as electron and proton microprobe techniques have been used in a detailed investigation of the modes of occurrence of arsenic and selenium in pyrite in Upper Freeport coal from the Homer City area, Indiana County, Pennsylvania. Polished blocks were prepared from columnar samples of the coal bed to represent particular zones continuously from top to bottom. Initial selection of zones to be studied was based on chemical analysis of bench-channel samples. Microprobe data indicate that the highest concentrations of arsenic (as great as 1. 5 wt. %) are apparently in solid solution in pyrite within a limited stratigraphic interval of the coal bed. Smaller amounts of arsenic and selenium (concentrations up to approximately 0. 1 and 0. 2 wt. % respectively) were detected at isolated points within pyrite grains in various strata of the coal bed.

Vertical-Control Subsystem for Automatic Coal Mining

NASA Technical Reports Server (NTRS)

Griffiths, W. R.; Smirlock, M.; Aplin, J.; Fish, R. B.; Fish, D.

1984-01-01

Guidance and control system automatically positions cutting drums of double-ended longwall shearer so they follow coal seam. System determines location of upper interface between coal and shale and continuously adjusts cutting-drum positions, upward or downward, to track undulating interface. Objective to keep cutting edges as close as practicable to interface and thus extract as much coal as possible from seam.

Petroleum geology and resources of the North Ustyurt Basin, Kazakhstan and Uzbekistan

USGS Publications Warehouse

Ulmishek, Gregory F.

2001-01-01

The triangular-shaped North Ustyurt basin is located between the Caspian Sea and the Aral Lake in Kazakhstan and Uzbekistan and extends offshore both on the west and east. Along all its sides, the basin is bounded by the late Paleozoic and Triassic foldbelts that are partially overlain by Jurassic and younger rocks. The basin formed on a cratonic microcontinental block that was accreted northward to the Russian craton in Visean or Early Permian time. Continental collision and deformation along the southern and eastern basin margins occurred in Early Permian time. In Late Triassic time, the basin was subjected to strong compression that resulted in intrabasinal thrusting and faulting. Jurassic-Tertiary, mostly clastic rocks several hundred meters to 5 km thick overlie an older sequence of Devonian?Middle Carboniferous carbonates, Upper Precambrian massifs and deformed Caledonian foldbelts. The Carboniferous?Lower Permian clastics, carbonates, and volca-basement is at depths from 5.5 km on the highest uplifts to 11 nics, and Upper Permian?Triassic continental clastic rocks, pri-km in the deepest depressions. marily red beds. Paleogeographic conditions of sedimentation, Three total petroleum systems are identified in the basin. the distribution of rock types, and the thicknesses of pre-Triassic Combined volumes of discovered hydrocarbons in these sysstratigraphic units are poorly known because the rocks have been tems are nearly 2.4 billion barrels of oil and 2.4 trillion cubic penetrated by only a few wells in the western and eastern basin feet of gas. Almost all of the oil reserves are in the Buzachi Arch areas. The basement probably is heterogeneous; it includes and Surrounding Areas Composite Total Petroleum System in 2 Petroleum Geology, Resources?North Ustyurt Basin, Kazakhstan and Uzbekistan the western part of the basin. Oil pools are in shallow Jurassic and Neocomian sandstone reservoirs, in structural traps. Source rocks are absent in the total petroleum system area; therefore, the oil could have migrated from the adjacent North Caspian basin. The North Ustyurt Jurassic Total Petroleum System encompasses the rest of the basin area and includes Jurassic and younger rocks. Several oil and gas fields have been discovered in this total petroleum system. Oil accumulations are in Jurassic clastic reservoirs, in structural traps at depths of 2.5?3 km. Source rocks for the oil are lacustrine beds and coals in the continental Jurassic sequence. Gas fields are in shallow Eocene sandstones in the northern part of the total petroleum system. The origin of the gas is unknown. The North Ustyurt Paleozoic Total Petroleum System stratigraphically underlies the North Ustyurt Jurassic system and occupies the same geographic area. The total petroleum system is almost unexplored. Two commercial flows of gas and several oil and gas shows have been tested in Carboniferous shelf carbonates in the eastern part of the total petroleum system. Source rocks probably are adjacent Carboniferous deep-water facies interpreted from seismic data. The western extent of the total petroleum system is conjectural. Almost all exploration drilling in the North Ustyurt basin has been limited to Jurassic and younger targets. The underlying Paleozoic-Triassic sequence is poorly known and completely unexplored. No wells have been drilled in offshore parts of the basin. Each of three total petroleum systems was assessed as a single assessment unit. Undiscovered resources of the basin are small to moderate. Most of the undiscovered oil probably will be discovered in Jurassic and Neocomian stratigraphic and structural traps on the Buzachi arch, especially on its undrilled off-shore extension. Most of the gas discoveries are expected to be in Paleozoic carbonate reservoirs in the eastern part of the basin.

The diversification of Paleozoic fire systems and fluctuations in atmospheric oxygen concentration

PubMed Central

Scott, Andrew C.; Glasspool, Ian J.

2006-01-01

By comparing Silurian through end Permian [≈250 million years (Myr)] charcoal abundance with contemporaneous macroecological changes in vegetation and climate we aim to demonstrate that long-term variations in fire occurrence and fire system diversification are related to fluctuations in Late Paleozoic atmospheric oxygen concentration. Charcoal, a proxy for fire, occurs in the fossil record from the Late Silurian (≈420 Myr) to the present. Its presence at any interval in the fossil record is already taken to constrain atmospheric oxygen within the range of 13% to 35% (the “fire window”). Herein, we observe that, as predicted, atmospheric oxygen levels rise from ≈13% in the Late Devonian to ≈30% in the Late Permian so, too, fires progressively occur in an increasing diversity of ecosystems. Sequentially, data of note include: the occurrence of charcoal in the Late Silurian/Early Devonian, indicating the burning of a diminutive, dominantly rhyniophytoid vegetation; an apparent paucity of charcoal in the Middle to Late Devonian that coincides with a predicted atmospheric oxygen low; and the subsequent diversification of fire systems throughout the remainder of the Late Paleozoic. First, fires become widespread during the Early Mississippian, they then become commonplace in mire systems in the Middle Mississippian; in the Pennsylvanian they are first recorded in upland settings and finally, based on coal petrology, become extremely important in many Permian mire settings. These trends conform well to changes in atmospheric oxygen concentration, as predicted by modeling, and indicate oxygen levels are a significant control on long-term fire occurrence. PMID:16832054

Depositional sequence stratigraphy and architecture of the cretaceous ferron sandstone: Implications for coal and coalbed methane resources - A field excursion

USGS Publications Warehouse

Garrison, J.R.; Van Den, Bergh; Barker, C.E.; Tabet, D.E.

1997-01-01

This Field Excursion will visit outcrops of the fluvial-deltaic Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale, known as the Last Chance delta or Upper Ferron Sandstone. This field guide and the field stops will outline the architecture and depositional sequence stratigraphy of the Upper Ferron Sandstone clastic wedge and explore the stratigraphic positions and compositions of major coal zones. The implications of the architecture and stratigraphy of the Ferron fluvial-deltaic complex for coal and coalbed methane resources will be discussed. Early works suggested that the southwesterly derived deltaic deposits of the the upper Ferron Sandstone clastic wedge were a Type-2 third-order depositional sequence, informally called the Ferron Sequence. These works suggested that the Ferron Sequence is separated by a type-2 sequence boundary from the underlying 3rd-order Hyatti Sequence, which has its sediment source from the northwest. Within the 3rd-order depositional sequence, the deltaic events of the Ferron clastic wedge, recognized as parasequence sets, appear to be stacked into progradational, aggradational, and retrogradational patterns reflecting a generally decreasing sediment supply during an overall slow sea-level rise. The architecture of both near-marine facies and non-marine fluvial facies exhibit well defined trends in response to this decrease in available sediment. Recent studies have concluded that, unless coincident with a depositional sequence boundary, regionally extensive coal zones occur at the tops of the parasequence sets within the Ferron clastic wedge. These coal zones consist of coal seams and their laterally equivalent fissile carbonaceous shales, mudstones, and siltstones, paleosols, and flood plain mudstones. Although the compositions of coal zones vary along depositional dip, the presence of these laterally extensive stratigraphic horizons, above parasequence sets, provides a means of correlating and defining the tops of depositional parasequence sets in both near-marine and non-marine parts of fluvial-deltaic depositional sequences. Ongoing field studies, based on this concept of coal zone stratigraphy, and detailed stratigraphic mapping, have documented the existence of at least 12 parasequence sets within the Last Chance delta clastic wedge. These parasequence sets appear to form four high frequency, 4th-order depositional sequences. The dramatic erosional unconformities, associated with these 4th-order sequence boundaries, indicate that there was up to 20-30 m of erosion, signifying locally substantial base-level drops. These base-level drops were accompanied by a basin ward shift in paleo-shorelines by as much as 5-7 km. These 4th-order Upper Ferron Sequences are superimposed on the 3rd-order sea-level rise event and the 3rd-order, sediment supply/accommodation space driven, stratigraphie architecture of the Upper Ferron Sandstone. The fluvial deltaic architecture shows little response to these 4th-order sea-level events. Coal zones generally thicken landward relative to the mean position of the landward pinch-out of the underlying parasequence set, but after some distance landward, they decrease in thickness. Coal zones also generally thin seaward relative to the mean position of the landward pinch-out of the underlying parasequence set. The coal is thickest in the region between this landward pinch-out and the position of maximum zone thickness. Data indicate that the proportion of coal in the coal zone decreases progressively landward from the landward pinch-out. The effects of differential compaction and differences in original pre-peat swamp topography have the effect of adding perturbations to the general trends. These coal zone systematics have major impact on approaches to exploration and production, and the resource accessment of both coal and coalbed methane.

Geometry and kinematics of Majiatan Fold-and-thrust Belt, Western Ordos Basin: implication for Tectonic Evolution of North-South Tectonic Belt

NASA Astrophysics Data System (ADS)

He, D.

2017-12-01

The Helan-Chuandian North-South Tectonic Belt crossed the central Chinese mainland. It is a boundary of geological, geophysical, and geographic system of Chinese continent tectonics from shallow to deep, and a key zone for tectonic and geomorphologic inversion during Mesozoic to Cenozoic. It is superimposed by the southeastward and northeastward propagation of Qinghai-Tibet Plateau in late Cenozoic. It is thus the critical division for West and East China since Mesozoic. The Majiatan fold-and-thrust belt (MFTB), locating at the central part of HCNSTB and the western margin of Ordos Basin, is formed by the tectonic evolution of the Helan-Liupanshan Mountains. Based on the newly-acquired high-resolution seismic profiles, deep boreholes, and surface geology, the paper discusses the geometry, kinematics, and geodynamic evolution of MFTB. With the Upper Carboniferous coal measures and the pre-Sinian ductile zone as the detachments, MFTB is a multi-level detached thrust system. The thrusting was mainly during latest Jurassic to Late Cretaceous, breaking-forward in the foreland, and resulting in a shortening rate of 25-29%. By structural restoration, this area underwent extension in Middle Proterozoic to Paleozoic, which can be divided into three phases of rifting such as Middle to Late Proterozoic, Cambiran to Ordovician, and Caboniferous to early Permian. It underwent compression since Late Triassic, including such periods as Latest Triassic, Late Jurassic to early Cretaceous, Late Cretaceous to early Paleogene, and Pliocene to Quaternary, with the largest shortening around Late Jurassic to early Cretaceous period (i.e. the mid-Yanshanian movement by the local name). However, trans-extension since Eocene around the Ordos Basin got rise to the formation the Yingchuan, Hetao, and Weihe grabens. It is concluded that MFTB is the leading edge of the intra-continental Helan orogenic belt, and formed by multi-phase breaking-forward thrusting during Late Jurassic to Cretaceous. During Cenozoic, MFTB is moderately modified by the northeastward compression due to the NE propagation of Qinghai-Tibet Plateau, and distinctly superimposed by the Yingchuan half-graben. North-South Tectonic Belt underwent a full cycle from extension during Middle Proterozoic to Paleozoic to compression since late Triassic.

Provenance analysis on detrital zircons from the back-arc Arivechi basin: Implications for the Upper Cretaceous tectonic evolution of northern Sonora and southern Arizona

NASA Astrophysics Data System (ADS)

Rodríguez-Castañeda, José Luis; Ortega-Rivera, Amabel; Roldán-Quintana, Jaime; Espinoza-Maldonado, Inocente Guadalupe

2018-07-01

In the Arivechi region of eastern Sonora, northwestern Mexico, mountainous exposures of Upper Cretaceous rocks that contain monoliths within coarse sedimentary debris are enigmatic, in a province of largely Late Cretaceous continental-margin arc rocks. The rocks sequence in the study area are grouped in two Upper Cretaceous units: the lower Cañada de Tarachi and the younger El Potrero Grande. Detrital zircons collected from three samples of the Cañada de Tarachi and El Potrero Grande units have been analyzed for U-Pb ages to constrain their provenance. These ages constrain the age of the exposed rocks and provide new insights into the geological evolution of eastern Sonora Cretaceous rocks. The detrital zircon age populations determined for the Cañada de Tarachi and El Potrero Grande units contain distinctive Precambrian, Paleozoic, and Mesozoic zircon ages that provide probable source areas which are discussed in detail constraining the tectonic evolution of the region. Comparison of these knew ages with published data suggests that the source terranes, that supplied zircons to the Arivechi basin, correlate with Proterozoic, Paleozoic and Mesozoic domains in southern California and Baja California, northern Sonora, southern Arizona and eastern Chihuahua. The provenance variation is vital to constrain the source of the Cretaceous rocks in eastern Sonora and support a better understanding of the Permo-Triassic Cordilleran Magmatic Arc in the southwestern North America.

Potential effects of surface coal mining on the hydrology of the upper Otter Creek-Pasture Creek Area, Moorehead coal field, southeastern Montana

USGS Publications Warehouse

McClymonds, N.E.; Moreland, J.A.

1988-01-01

The combined upper Otter Creek-Pasture Creek area, south of Ashland, Montana, contains large reserves of Federal coal for potential lease sale. A hydrologic study was conducted in the area to describe existing hydrologic systems and generalized groundwater quality, to assess potential effects of surface mining on local water resources, and to evaluate the potential for reclamation of those water resources. Principal aquifers are coal beds and sandstone in the upper Tongue River Member of the Fort Union Formation (Paleocene age), and sand and gravel in alluvium (Pleistocene and Holocene age). Hydraulic conductivity determined from aquifer tests was about 0.004 to 16 ft/d for coal or sandstone aquifers and 1 to 290 ft/d for alluvial aquifers. Dissolved-solids concentrations in water from bedrock ranged from 1,160 to 4,390 mg/L. In alluvium, the concentrations were 1,770 to 12,600 mg/L. Surface water is available from interrupted flow along downstream reaches of Otter and Pasture Creeks, from stock ponds, and from springs. Most stock ponds are dry by midsummer. Mining of coal in the Anderson, Dietz, and Canyon beds would lower the potentiometric surface within coal and sandstone aquifers. Alluvium along Otter Creek, its main tributaries, and Pasture Creek would be removed at the mines. Planned structuring of the spoils and reconstruction of alluvial aquifers could minimize downstream changes in water quality. Although mining would alter the existing hydrologic systems and destroy several shallow wells and stock ponds, alternative water supplies are available. (USGS)

Devonian paleomagnetism of the North Tien Shan: Implications for the middle-Late Paleozoic paleogeography of Eurasia

NASA Astrophysics Data System (ADS)

Levashova, Natalia M.; Mikolaichuk, Alexander V.; McCausland, Philip J. A.; Bazhenov, Mikhail L.; Van der Voo, Rob

2007-05-01

The Ural-Mongol belt (UMB), between Siberia, Baltica and Tarim, is widely recognized as the locus of Asia's main growth during the Paleozoic, but its evolution remains highly controversial, as illustrated by the disparate paleogeographic models published in the last decade. One of the largest tectonic units of the UMB is the Kokchetav-North Tien Shan Domain (KNTD) that stretches from Tarim in the south nearly to the West Siberian Basin. The KNTD comprises several Precambrian microcontinents and numerous remnants of Early Paleozoic island arcs, marginal basins and accretionary complexes. In Late Ordovician time, all these structures had amalgamated into a single contiguous domain. Its paleogeographic position is of crucial importance for elucidating the Paleozoic evolution of the UMB in general and of the Urals in particular. The Aral Formation, located in Kyrgyzstan in the southern part of the KNTD, consists of a thick Upper Devonian (Frasnian) basalt-andesite sequence. Paleomagnetic data show a dual-polarity characteristic component (Dec/Inc = 286° / + 56°, α95 = 9°, k = 21, N = 15 sites). The primary origin of this magnetization is confirmed by a positive test on intraformational conglomerates. We combine this result with other Paleozoic data from the KNTD and show its latitudinal motion from the Late Ordovician to the end of the Paleozoic. The observed paleolatitudes are found to agree well with the values extrapolated from Baltica to a common reference point (42.5°N, 73°E) in our sampling area for the entire interval; hence coherent motion of the KNTD and Baltica is strongly indicated for most of the Paleozoic. This finding contradicts most published models of the UMB evolution, where the KNTD is separated from Baltica by a rather wide Ural Ocean containing one or more major plate boundaries. An exception is the model of Şengör and Natal'in [A.M.C. Şengör, B.A. Natal'in, Paleotectonics of Asia: fragments of a synthesis, in: A. Yin and M. Harrison (eds.), The tectonic evolution of Asia, Cambridge University Press, Cambridge (1996) 486-640], in which coherent paleolatitudinal motion of Baltica and the KNTD is hypothesized — the latter as part of the Kipchak Arc. We suggest a parallel hypothesis, which explains coherent motion of the KNTD and Baltica. In particular, we argue that if a basin with oceanic crust ever existed between the KNTD and Baltica, it was a narrow one without (significant) active spreading in Middle to Late Paleozoic time. Notably, the paleogeographic position of Siberia during the Middle Paleozoic and hence, the width of the Khanty-Mansi Ocean between Siberia, on the one hand, and Baltica-KNTD, on the other hand, remains largely unconstrained, because of the paucity of high-quality Silurian, Devonian and Carboniferous paleomagnetic results from Siberia.

Coalification of organic matter in coal balls of the Pennsylvanian (upper Carboniferous) of the Illinois Basin, United States

USGS Publications Warehouse

Lyons, P.C.; Thompson, C.L.; Hatcher, P.G.; Brown, F.W.; Millay, M.A.; Szeverenyi, N.; Maciel, G.E.

1984-01-01

An evaluation was made of the degree of coalification of two coal balls from the Illinois Basin of the Pennsylvanian (upper Carboniferous) of the United States. Previous interpretations are mainly misleading and contradictory, primarily because of the assumption that the brown color and exceptional cellular and subcellular preservation typical of American coal balls imply chemical preservation of cellulose and lignin, the primary components of peat. Xylem tissue from a medullosan seed fern contained in a coal ball and the coal attached to the coal ball from the Calhoun coal bed, Mattoon Formation, Illinois, was analyzed by elemental, petrographic, and nuclear magnetic resonance (NMR) techniques to determine the degree of coalification. The NMR and elemental data indicate the lack of cellulose and lignin and a probable rank of high-volatile C bituminous coal. These data corroborate data for a coal ball from the Herrin (No. 6) coal bed (Carbondale Formation, Middle Pennsylvanian) and support our hypothesis that the organic matter in coal balls of the Pennsylvanian strata of the United States is coalified to about the same degree as the surrounding coal. Data presented show a range of lower reflectances for xylem tissue and vitrinite in the analyzed coal balls compared with vitrinite in the attached coal. The data reported indicate that physical preservation of organic matter in coal balls does not imply chemical preservation. Also our study supports the hypothesis that compactional (static load) pressure is not a prerequisite for coalification up to a rank of high-volatile C bituminous coal. A whole-rock analysis of the Calhoun coal ball indicates a similarity to other carbonate coal balls from the United States. It consists primarily of calcium carbonate and 1-2% organic matter; silica and alumina together make up less than 0.5%, indicating the lack of minerals such as quartz and clays. ?? 1984.

Brown coal maceral distributions in a modern domed tropical Indonesian peat and a comparison with maceral distributions in Middle Pennsylvanian–age Appalachian bituminous coal beds

USGS Publications Warehouse

Grady, William C.; Eble, Cortland F.; Neuzil, Sandra G.

1993-01-01

Analyses of modern Indonesian peat samples reveal that the optical characteristics of peat constituents are consistent with the characteristics of macerals observed in brown coal and, as found by previous workers, brown-coal maceral terminology can be used in the analysis of modern peat. A core from the margin and one from near the center of a domed peat deposit in Riau Province, Sumatra, reveal that the volume of huminite macerals representing well-preserved cell structures (red, red-gray, and gray textinite; ulminite; and corpo/textinite) decreases upward. Huminite macerals representing severely degraded (<20 microns) cellular debris (degraded textinite, attrinite, and densinite) increase uniformly from the base to the surface. Greater degradation of the huminite macerals in the upper peat layers in the interior of the deposit is interpreted to be the result of fungal activity that increased in response to increasingly aerobic conditions associated with the doming of the peat deposit. Aerobic conditions concurrent with the activities of fungi may result in incipient oxidation of the severely degraded huminite macerals. This oxidation could lead to the formation of degradosemifusinite, micrinite, and macrinite maceral precursors in the peat, which may become evident only upon coalification. The core at the margin was petrographically more homogeneous than the core from the center and was dominated by well-preserved huminite macerals except in the upper 1 m, which showed signs of aerobic degradation and was similar to the upper 1 m of the peat in the interior of the deposit.The Stockton and other Middle Pennsylvanian Appalachian coal beds show analogous vertical trends in vitrinite maceral composition. The succession from telocollinite-rich, bright coal lithotypes in the lower benches upward to thin-banded/matrix collinite and desmocollinite in higher splint coal benches is believed to reflect a progression similar to that from the well-preserved textinite macerals in the lower portions of the peat cores to severely fragmented and degraded cellular materials (degraded textinite, attrinite, and densinite) in the upper portions of the cores. This petrographic sequence from bright to splint coal in the Stockton and other Middle Pennsylvanian coal beds supports previous interpretations of an upward transition from planar to domed swamp accumulations.

Facies development in the Lower Freeport coal bed, west-central Pennsylvania, U.S.A.

USGS Publications Warehouse

Pierce, B.S.; Stanton, R.W.; Eble, C.F.

1991-01-01

The Lower Freeport coal bed in west-central Pennsylvania is interpreted to have formed within a lacustrine-mire environment. Conditions of peat formation, caused by the changing chemical and physical environments, produced five coal facies and two mineral-rich parting facies within the coal bed. The coal bed facies are compositionally unique, having developed under varying conditions, and are manifested by megascopic, petrographic, palynologic and quality characteristics. The initial environment of the Lower Freeport peat resulted in a coal facies that is relatively high in ash yield and contains large amounts of lycopod miospores and moderate abundances of cryptotelinite, crypto-gelocollinite, inertinite and tree fern miospores. This initial Lower Freeport peat is interpreted to have been a topogenous body that was low lying, relatively nutrient rich (mesotrophic to eutrophic), and susceptible to ground water and to sediment influx from surface water. The next facies to form was a ubiquitous, clay-rich durain parting which is attributed to a general rise in the water table accompanied by widespread flooding. Following formation of the parting, peat accumulation resumed within an environment that inhibited clastic input. Development of doming in this facies restricted deposition of the upper shale parting to the margins of the mire and allowed low-ash peat to form in the interior of the mire. Because this environment was conducive to preservation of cellular tissue, this coal facies also contains large amounts of crypto-telinite. This facies development is interpreted to have been a transitional phase from topogenous, planar peat formation to slightly domed, oligotrophic (nutrient-poor) peat formation. As domed peat formation continued, fluctuations in the water table enabled oxidation of the peat surface and produced high inertinite concentrations toward the top of the coal bed. Tree ferns became an increasingly important peat contributor in the e upper facies, based on the palynoflora. This floral change is interpreted to have resulted from the peat surface becoming less wet or better drained, a condition that inhibited proliferation of lycopod trees. Accumulation of the peat continued until rising water levels formed a freshwater lake within which clays and silts were deposited. The development of the Lower Freeport peat from a planar mire through transitional phases toward domed peat formation may be an example of the type of peat formation of other upper Middle and Upper Pennsylvanian coal beds. ?? 1991.

Late Paleozoic transpression in Buenos Aires and northeast Patagonia ranges, Argentina

NASA Astrophysics Data System (ADS)

Rossello, E. A.; Massabie, A. C.; López-Gamundí, O. R.; Cobbold, P. R.; Gapais, D.

1997-12-01

Paleozoic sediments are present in three regions in eastern central Argentina: (1) the Sierras Australes of Buenos Aires, (2) Sierras Septentrionales of Buenos Aires and (3) Northeast Patagonia. All of these deposits share a common deformational imprint imparted by late Paleozoic Gondwanan deformation. Exposures of these rocks are scattered, variably deformed, and isolated by younger sediments deposited in basins related to the Mesozoic through Tertiary opening of the South Atlantic such as the offshore Colorado Basin. The Sierras Australes of Buenos Aires outcrops are the best preserved. They are mostly located along the Sierras Australes foldbelt, with minor outliers distributed in the adjacent Claromec-basin. The Tunas Formation (early-early late? Permian) is the uppermost unit of the Pillahuincó Group (late Carboniferous-Permian) and is crucial to the understanding of the tectono-sedimentary evolution of the region during the late Paleozoic. The underlying units of the Pillahuincó Group (Sauce Grande, Piedra Azul and Bonete Formations) exhibit a depositional and compositional history characterized by glaciomarine sedimentation and postglacial transgression. They are also characterized by rather uniform quartz-rich compositions indicative of a cratonic provenance from the La Plata craton to the NE. In contrast, the sandstone-rich Tunas Formation has low quartz contents, and abundant volcanic and metasedimentary fragments; paleocurrents are consistently from the SW. Glassrich tuffs are interbedded with sandstone in the upper half of the Tunas Formation. The age of the deformation in the Sierras Australes is Permian and early-middle Triassic. This is based on metamorphic events indicated by formation of illite at 282 ± 3 Ma, 273 ± 8 Ma, 265 ± 3 Ma, and 260 ± 3 Ma ( {K}/{Ar} illite) in the Silurian Curamalal Group. Evidence of syntectonic magmatism is provided by a radiometric date of 245 ± 12 Ma ( {K}/{Ar} hornblende) for the López Lecube Granite, immediately west of the Sierras Australes. In the Sierras Septentrionales of Buenos Aires, Precambrian through early Paleozoic deposits of La Tinta, Sierras Bayas, Las Aguilas and Balcarce Formations rest on Precambrian crystalline basement of the La Plata craton. These exposed rocks are affected by subordinate, right lateral wrench faulting; some thrusting indicates tectonic transport toward the NE. In northeast Patagonia (Sierra Grande region) synkinematic deformation of early Permian (261 ± 5 Ma, {Rb}/{Sr} whole rock) age has been identified in Silurian metasediments of the Sierra Grande Formation. Bands of deformation in Sierra Grande quartzites indicate right lateral wrenching in a N-S direction. Contraction in a NE-SW direction is evidenced by folding. Three stages of tectonic evolution can be discerned for the above regions: (1) Early Paleozoic platform sedimentation, punctuated by episodes of accelerated subsidence during the Silurian and early Devonian, as shown by transgressive episodes, (2) late Paleozoic sedimentation and deformation, and (3) Meso-Cenozoic extensional inversion due to the South Atlantic opening. The late Paleozoic sedimentation and deformation (stage 2) includes late Carboniferous-earliest Permian glacial deposits of the Sierras Australes and Colorado offshore basin, deposited during an initial phase of extension, and cratonward foreland subsidence triggered sedimentation of the synorogenic deposits of the Permian Tunas Formation. Tuffs are intercalated in the upper half of this unit. These tuffs are associated with the silicic volcanism along the Andes and Patagonia (Choiyoi magmatic province) that peaked between the late early Permian and late Permian. Likewise, the first widespread appearance of tuffs in the Karoo basin is in the Whitehill Formation, of late early Permian (260 Ma) age. The deformation described in this paper can be considered as part of a large scale intracontinental deformation in SW Gondwanaland inboard of an Andean-type compressive margin. This deformation is characterized by transpression (right lateral wrenching) combined with overthrusting to the NE and N-S horizontal contraction.

Effects of bedrock geology on source and flowpath of runoff water in steep unchanneled hollows

NASA Astrophysics Data System (ADS)

Uchida, T.; Asano, Y.; Kosugi, K.; Ohte, N.; Mizuyama, T.

2001-05-01

Simultaneous measurements of runoff, soil pore water pressure and soil temperature were taken to evaluate the spatial and temporal nature of flowpaths and flow sources in steep unchanneled hollows in central Japan. Two small hollows were monitored; one is underlain by granite and one is underlain by Paleozoic shale. In both catchments, tensiometers showed that a saturated area formed in the areas near a spring. The soil temperature suggests that in the small perennially saturated area near the spring, water percolating through the vadose zone mixed with water emerging from the bedrock. During rainstorms, the streamflow varied with the soil pore water pressure on the upper slope; the soil pore water pressure in the area near the spring remained nearly constant._@ Moreover, the spring water temperature was almost the same as the transient groundwater temperature on the upper slope. This indicates that the transient groundwater in the upper slope flowed to the spring via lateral preferential paths in both catchments. During summer rainstorms, the soil-bedrock interface temperature increased as the ground became saturated in the granite hollow, suggesting that both rainwater and shallow soil water had important effects on the formation of transient saturated groundwater on the upper slope. That is, it can be concluded that the contribution of the bedrock groundwater to the streamflow was relatively small in the granite hollow during storm runoff. The area where the bedrock groundwater seeped into the soil mantle did not grow in size as the contributing area for the streamflow extended to the upper hollow in the granite catchment. In contrast, the soil temperature indicated that after heavy rainfall (77.5 mm), bedrock groundwater played an important role in the formation of the transient groundwater in the Paleozoic shale hollow. Consequently, the contribution of the bedrock groundwater to the streamflow was relatively large in the shale hollow after heavy rainfall.

Maps showing the distribution of uranium-deposit clusters in the Colorado Plateau uranium province

USGS Publications Warehouse

Finch, Warren I.

1991-01-01

The Colorado Palteau Uranium Province (CPUP) is defined by the distribution of uranium deposits, chiefly the sandstone-type, in upper Paleozoic and Mesozoic sedimentary rocks within the Colorado Plateau physiographic province (Granger and others, 1986).  The uranium province is bordered by widely distributed and mostly minor uranium deposits in Precambrian and Tertiary rocks and by outcrops of Tertiary extrusive and intrusive igneous rocks.  

Conodont color alteration index and upper Paleozoic thermal history of the Amazonas Basin, Brazil

NASA Astrophysics Data System (ADS)

Cardoso, Cassiane Negreiros; Sanz-López, Javier; Blanco-Ferrera, Silvia; Lemos, Valesca Brasil; Scomazzon, Ana Karina

2015-12-01

The conodont color alteration index (CAI) was determined in elements from core samples of the Frasnian Barreirinha Formation (one well) and of the Pennsylvanian-Permian Tapajós Group (twenty three wells and one limestone quarry) in the Amazonas Basin. The thermal history of the basin is analyzed using the CAI value distribution represented in maps and stratigraphic sections through correlation schemes, and in conjunction with previously published data. The pattern of palaeotemperatures for CAI values of 1.5-3 is coincident with organic matter maturation under a sedimentary overburden providing diagenetic conditions in the oil/gas window. Locally, conodonts show metamorphism (CAI value of 6-7) in relation to the intrusion of diabase bodies in beds including high geothermal gradient evaporites. Microtextural alteration on the surface conodonts commonly shows several types of overgrowth microtextures developed in diagenetic conditions. Locally, recrystallization in conodonts with a high CAI value is congruent with contact metamorphism in relation to Mesozoic intrusions. The CAI values of 1.5 or 2 observed close to the surface in several areas of the basin may be interpreted in relation to a high thermal palaeogradient derived from the magmatic episode or/and to the local denudation of the upper part of the Paleozoic succession prior to this thermal event.

Formation of most of our coal brought Earth close to global glaciation.

PubMed

Feulner, Georg

2017-10-24

The bulk of Earth's coal deposits used as fossil fuel today was formed from plant debris during the late Carboniferous and early Permian periods. The high burial rate of organic carbon correlates with a significant drawdown of atmospheric carbon dioxide (CO 2 ) at that time. A recent analysis of a high-resolution record reveals large orbitally driven variations in atmospheric CO 2 concentration between [Formula: see text]150 and 700 ppm for the latest Carboniferous and very low values of 100 [Formula: see text] 80 ppm for the earliest Permian. Here, I explore the sensitivity of the climate around the Carboniferous/Permian boundary to changes in Earth's orbital parameters and in atmospheric CO 2 using a coupled climate model. The coldest orbital configurations are characterized by large axial tilt and small eccentricities of Earth's elliptical orbit, whereas the warmest configuration occurs at minimum tilt, maximum eccentricity, and a perihelion passage during Northern hemisphere spring. Global glaciation occurs at CO 2 concentrations <40 ppm, suggesting a rather narrow escape from a fully glaciated Snowball Earth state given the low levels and large fluctuations of atmospheric CO 2 These findings highlight the importance of orbital cycles for the climate and carbon cycle during the late Paleozoic ice age and the climatic significance of the fossil carbon stored in Earth's coal deposits.

Interfingering of the Frontier Formation and Aspen Shale, Cumberland Gap, Wyoming.

USGS Publications Warehouse

M'gonigle, J.

1982-01-01

The basal part, or the Chalk Creek Member, of the non-marine lower Frontier Formation (Upper Cretaceous) includes a thin coal bed that grades S into a carbonaceous shale. The latter plus associated sandstones and shales pinch out S of Cumberland Gap and lie stratigraphically below the top of the Aspen Shale. The beds in the upper part of the Aspen, in turn, pinch out within the Frontier Formation. The coal bed and equivalent carbonaceous shale represent in-place accumulation of peat. The interfingering suggests that in SW Wyoming the Lower/Upper Cretaceous boundary is within the Chalk Creek Member. -from Author

Development of low-ash, planar peat swamps in an alluvial-plain setting: The no. 5 Block beds (westphalian D) of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1993-07-01

Coals from the No. 5 Block coal beds (Westphalian D) of the central Appalachian basin are noted for their blocky, dull character and their low ash and low sulfur content. The beds are multiple benched, with rock partings separating benches. Individual benches have limited lateral extent and, where thick, are dominated by bright, high-ash coal at the base and dull, low-ash coal in the upper parts. The duller coals contain more exinite-group and inertinite-group macerals than the brighter coals. These coal beds are encased in sandstone units dominated by fining-upward sequences. The overall depositional setting is an alluvial-plain environment withmore » northwest-flowing channels spaced approximately 20 km apart. The channels were flanked by clastic swamps about 7 km wide. Low-ash peat accumulated in areas of the flood plain most distant from the channels. These peat-accumulating swamps were about 8 km across. In a few instances low-frequency flood events introduced fine siliciclastic sediment into the peat swamps, depositing a thin layer of sediment on top of the peat. This sediment layer is thicker where the underlying coal is the thickest. These thick coal areas are topographically lower than surrounding coal areas. This relationship between coal thickness, parting thickness, and topography indicates that these peat swamps were planar at the time of deposition. Individual coal benches contain abundant preserved cellular tissue (telocollinite, semifusinite, and fusinite) at most locations, suggesting that robust vegetation was widespread in the swamps and that the morphology was planar. The high concentrations of exinite-group an inertinite-group macerals in the upper parts of benches resulted from selective decomposition and oxidation of the peat in subaerial and aquatic planar-swamp environments.« less

Stratigraphic framework and coal correlation of the Upper Cretaceous Fruitland Formation, Bisti-Ah-Shi-Sle-Pah area, San Juan Basin, New Mexico

USGS Publications Warehouse

Flores, Romeo M.; Erpenbeck, Michael F.

1982-01-01

This report illustrates and describes the detailed stratigraphic framework and coal correlation of the Upper Cretaceous Fruitland Formation exposed in isolated badlands and along washes within a 20-mile outcrop belt in the Bisti-Ah-Shi-Sle-Pah area, southwestern San Juan Basin, Nex Mexico (see index). The stratigraphic framework showing the vertical and lateral distributions of rock types and the lateral continuity of coal beds is illustrated in cross sections. The cross sections were constructed from 112 stratigraphic sections measured at an average distance of 0.4 mi apart. Each section contained key marker beds (sandstone, coal, and tonstein) that were physically traced to adjacent sections. Each measured section was "hung" on multiple marker beds arranged in a geometric best-fit method that accounts for the differential compaction and facies associations of the deposits. 

Trace elements reconnaissance investigations in New Mexico and adjoining states in 1951

USGS Publications Warehouse

Bachman, George O.; Read, Charles B.

1952-01-01

In the summer and fall of 1951, a reconnaissance search was made in New Mexico and adjacent states for uranium in coal and carbonaceous shale, chiefly of Mesozoic age, and black marine shale of Paleozoic age. Tertiary volcanic rocks, considered to be a possible source for uranium in the coal and associated rocks, were examined where the volcanic rocks were near coal-bearing strata. Uranium in possibly commercial amounts was found at La Ventana Mesa, Sandoval County, New Mexico. Slightly uranifeous coal and carbonaceous shale were found near San Ysidro, Sandoval County, and on Beautiful Mountain, San Juan County, all in New Mexico, and at Keams Canyon, Navajo County, and near Tuba City, Coconino County, in Arizona. Except for La Ventana deposit, none appeared to be of economic importance at the time this report was written, but additional reconnaissance investigations have been underway this field season, in the area where the deposits occur. Marine black shale of Sevonian age was examined in Otero and Socorro Counties, New Mexico and Gila County, Arizona. Mississippian black shale in Socorro County and Pennsylvanian black shale in Taos County, New Mexico were also tested. Equivalent uranium content of samples of these shales did not exceed 0.004 percent. Rhyolitic tuff from the Mount Taylor region is slightly radioactive as is the Bandelier tuff in the Nacimiento region and in the Jemez Plateau. Volcanic rocks in plugs and dikes in the northern Chuska Mountains and to the north in New Mexico as well as in northeastern Arizona and southeastern Utah are slightly radioactive. Coal and carbonaceous rocks in the vicinity of these and similar intrusions are being examined.

Estimation of Coal Reserves for UCG in the Upper Silesian Coal Basin, Poland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bialecka, Barbara

One of the prospective methods of coal utilization, especially in case of coal resources which are not mineable by means of conventional methods, is underground coal gasification (UCG). This technology allows recovery of coal energy 'in situ' and thus avoid the health and safety risks related to people which are inseparable from traditional coal extraction techniques.In Poland most mining areas are characterized by numerous coal beds where extraction was ceased on account of technical and economic reasons or safety issues. This article presents estimates of Polish hard coal resources, broken down into individual mines, that can constitute the basis ofmore » raw materials for the gasification process. Five mines, representing more than 4 thousand tons, appear to be UCG candidates.« less

Determination of Destress Blasting Effectiveness Using Seismic Source Parameters

NASA Astrophysics Data System (ADS)

Wojtecki, Łukasz; Mendecki, Maciej J.; Zuberek, Wacaław M.

2017-12-01

Underground mining of coal seams in the Upper Silesian Coal Basin is currently performed under difficult geological and mining conditions. The mining depth, dislocations (faults and folds) and mining remnants are responsible for rockburst hazard in the highest degree. This hazard can be minimized by using active rockburst prevention, where destress blastings play an important role. Destress blastings in coal seams aim to destress the local stress concentrations. These blastings are usually performed from the longwall face to decrease the stress level ahead of the longwall. An accurate estimation of active rockburst prevention effectiveness is important during mining under disadvantageous geological and mining conditions, which affect the risk of rockburst. Seismic source parameters characterize the focus of tremor, which may be useful in estimating the destress blasting effects. Investigated destress blastings were performed in coal seam no. 507 during its longwall mining in one of the coal mines in the Upper Silesian Coal Basin under difficult geological and mining conditions. The seismic source parameters of the provoked tremors were calculated. The presented preliminary investigations enable a rapid estimation of the destress blasting effectiveness using seismic source parameters, but further analysis in other geological and mining conditions with other blasting parameters is required.

Palaeoenvironmental reconstruction of Hüsamlar coal seam, SW Turkey

NASA Astrophysics Data System (ADS)

Büçkün, Zeynep; İnaner, Hülya; Oskay, Riza Görkem; Christanis, Kimon

2015-06-01

The Ören and Yatağan Basins in SW Turkey host several Miocene coal deposits currently under exploitation for power generation. The present study aims to provide insight into the palaeoenvironmental conditions, which controlled the formation of the Hüsamlar coal seam located in Ören Basin. The coal seam displays many sharp alternations of matrix lignite beds and inorganic, lacustrine sediment layers. The coal is a medium-to-high ash lignite (10.47-31.16 wt%, on dry basis) with high total sulphur content (up to 10 wt%, on dry, ash-free basis), which makes it prone to self-combustion. The maceral composition indicates that the peat-forming vegetation consisted of both arboreal and herbaceous plants, with the latter being predominant in the upper part of the seam. Mica and feldspars contribute to the low part of the seam; carbonates are dominant in the upper part, whereas quartz and pyrite are present along the entire coal profile. The sudden transitions of the telmatic to the lacustrine regime and reverse is attributed to tectonic movements that controlled water table levels in the palaeomire, which affected surface runoff and hence, clastic deposition.

Reworked crustal of early Paleozoic WuYi Orogen revealed by receiver function data

NASA Astrophysics Data System (ADS)

Wei, Y.; Duan, Y.; Tian, X.; Zhao, Y.

2017-12-01

Intraplate orogenic belt, which occurs at the rigid and undeformable plate interiors, is a distinct new type of orogen rather than an interplate or plate marginal orogenic belt, whose deformation occurs exclusively at plate margins. Therefore, intraplate orogenic belts are the most obvious exception to the plate-tectonic paradigm, they are uncommon in Earth's history. The early Paleozoic Wuyi orogen in South China is one of the few examples of intraplate orogen, and is a key to understanding the process of intraplate orogenesis and global early Paleozoic geodynamics. In this study, we select teleseismic records from 45 mobile linear seismic stations deployed in Wuyi Mountain and 58 permanent stations setting in Jiangxi and Fujian provinces, from January 2011 to December 2012, and calculate the crustal thickness and average crustal Vp/Vs ratio using the H-κ stacking method. The main results include the following: 1) the crustal average Poission's ratio shows an increase tendency from land to sea, the interior of Wuyi orogen belt with an low ration less than 0.23, and the coastline with high ration which is up to 0.28, which indicate a very heterogeneous crustal structure and composition in Wuyi orogen and coast belt. 2) the crustal thickness ranges 28-34 km and shows a tendency of thinning from inland to coast in the region of SE China margin, which maight mean the eastern Eurasia lithospheric is extension and thinning induced by the subducted paleo-Pacific slab. To conclusion, we assume that Wuyi orogen experienced upper crustal thickening, lower crust and lithosphere delamination during the early Paleozoic orogeny, and lithosphere extension in Mesozoic. This research is founded by the Natural Science Foundation of China (41174052 and 41604048).

Inheritance, Variscan tectonometamorphic evolution and Permian to Mesozoic rejuvenations in the metamorphic basement complexes of the Romanian Carpathians revealed by monazite microprobe geochronology

NASA Astrophysics Data System (ADS)

Săbău, Gavril; Negulescu, Elena

2014-05-01

Monazite U-Th-Pb chemical dating reaches an acceptable compromise between precision and accuracy on one side, and spatial resolution and textural constraints on the other side. Thus it has a powerful potential in testing the coherence of individual metamorphic basement units, and enabling correlations among them. Yet, sensitivity and specificity issues in monazite response to thermotectonic events, especially in the case of superposed effects, remain still unclear. Monazite dating at informative to detailed scale in the main metamorphic basement units of the Carpathians resulted in complex age spectra. In the main, the spectra are dominated by the most pervasive thermal and structural overprint, as checked against independent geochronological data. Post-peak age resetting is mostly present, but statistically subordinate. Resetting in case of superposed events is correlated with the degree of textural and paragenetic overprinting, inheritances being always indicated by more or less well-defined age clusters. The lack of relict ages correlating with prograde structural and porphyroblast zonation patterns is indicative for juvenile formations. Age data distribution in the Carpathians allowed distinction of pre-Variscan events, syn-metamorphic Variscan tectonic stacking of juvenile and reworked basement, post-Variscan differential tectonic uplift, as well as prograde metamorphic units ranging down to Upper Cretaceous ages. In the South Carpathians, the Alpine Danubian domain consists of several Variscan and Alpine thrust sheets containing a metamorphic complex dominated by Upper Proterozoic to Lower Cambrian metamorphic and magmatic ages (Lainici-Păiuş), and several complexes with metamorphic overprints ranging from Carboniferous to Lower Permian. Any correlation among these units, as well as geotectonic models placing a Lower Paleozoic oceanic domain between pre-existing Lainici-Păiuş and Drăgşan terranes are precluded by the age data. Other basement of the South Carpathians contain lower Paleozoic or older units intruded by Ordovician granitoids, imbricated with juvenile Variscan slivers, the structural sequence differing in individual basement complexes. So, in the Leaota Massif the lowermost term of the sequence is prograde Variscan, tectonically overlain by reworked lower Paleozoic gneisses, supporting thrust sheets with very low- to low-grade Variscan schists. In the Făgăraş Massif a lower Paleozoic (Cumpăna) complex bearing a strong Variscan overprint, straddles Variscan juvenile rocks, and the lowermost visible structural level is assumed by upper Carboniferous to Permian juvenile medium-grade metamorphic schists. In the Lotru Metamorphic Suite of the Alpine Getic Nappe, the Variscan stacking is overprinted by post-orogenic differential uplift, documented by the correlation among younging ages, structural and metamorphic low-pressure overprints, recording often higher metamorphic temperatures. The most spectacular structure is Upper Jurassic in age, contains high-grade metamorphic rocks and peraluminous anatectic granitoids, is outlined by a deformed boundary evolving from ductile to brittle regime during cooling, and induces a thermal overprint in the neighbouring rocks. In the basement units thrust over the Getic Nappe, the Sibişel unit yielded Permian prograde peak metamorphic ages and Triassic post-peak overprints, while an adjacent gneissic unit (Laz) delivered an exclusively Cretaceous age pattern. Unexpectedly young metamorphic ages resulted also for the East Carpathians and the Apuseni Mountains. While most of the ages obtained so far correspond to Variscan retrogression of older basement units, the lowermost structural unit of the infra-Bucovinian nappe system in the East Carpathians yielded Upper Cretaceous metamorphic ages in apparently monometamorphic medium-grade schists. In the Apuseni Mountains, schists of the Baia de Arieş Unit display an Upper Jurassic age spectrum, corresponding to a clearly prograde medium-grade event. The ages recorded not only question some of the currently accepted correlations among basement units, but urge to reconsideration of the way in which the basement-cover relationships are interpreted and extrapolated.

Bedded Barite Deposits from Sonora (nw Mexico): a Paleozoic Analog for Modern Cold Seeps

NASA Astrophysics Data System (ADS)

Canet, C.; Anadón, P.; González-Partida, E.; Alfonso, P.; Rajabi, A.; Pérez-Segura, E.; Alba-Aldave, L. A.

2013-05-01

The Mazatán barite deposits represent an outstanding example of Paleozoic bedded barite, a poorly understood type of mineral deposit of major economic interest. The largest barite bodies of Mazatán are hosted within an Upper Carboniferous flysch succession, which formed part of an accretionary wedge related to the subduction of the Rheic Ocean beneath Gondwana. As well, a few barite occurrences are hosted in Upper Devonian, pre-orogenic turbidites. A variety of mineralized structures is displayed by barite, including: septaria nodules, enterolitic structures, rosettes and debris-flow conglomerates. Barite is accompanied by chalcedony, pyrite (framboids) and berthierine. Gas-rich fluid inclusions in barite were analyzed by Raman spectroscopy and methane was identified, suggesting the occurrence of light hydrocarbons in the environment within which barite precipitated. 13C-depleted carbonates (δ13C: -24.3 to -18.8‰) were found in the barite deposits; they formed through anaerobic oxidation of methane coupled to sulfate reduction, and yield negative δ18O values (-11.9 to -5.2‰) reflecting the isotopic composition of Devonian-Carboniferous seawater. Methane-derived carbonates occur in modern hydrocarbon seeps and have been reported from Mesozoic and Cenozoic seep sediments, but they have never before been described in Paleozoic bedded barite deposits. δ34S of barite varies from +17.6 to +64.1‰, with the lowest values overlapping the range for coeval seawater sulfate; this distribution indicates a process of sulfate reduction. Barite precipitation can be explained by mixing of methane- and barium-rich fluids with pore-water (seawater) containing sulfate residual from microbial reduction. Two analyses from barite gave an 87Sr/86Sr within and slightly above the range for seawater at the time of deposition, with 0.708130 and 0.708588, which would preclude the involvement of hydrothermal fluids in the mineralization process.

The rise and fall of late Paleozoic trilobites of the United States

USGS Publications Warehouse

Brezinski, D.K.

1999-01-01

Based on range data and generic composition, four stages of evolution are recognized for late Paleozoic trilobites of the contiguous United States. Stage 1 occurs in the Lower Mississippian (Kinderhookian-Osagean) and is characterized by a generically diverse association of short-ranging, stenotopic species that are strongly provincial. Stage 2 species are present in the Upper Mississippian and consist of a single, eurytopic, pandemic genus, Paladin. Species of Stage 2 are much longer-ranging than those of Stage 1, and some species may have persisted for as long as 12 m.y. Stage 3 is present within Pennsylvanian and Lower Permian strata and consists initially of the eurytopic, endemic genera Sevillia and Ameura as well as the pandemic genus Ditomopyge. During the middle Pennsylvanian the very long-ranging species Ameura missouriensis and Ditomopyge scitula survived for more than 20 m.y. During the late Pennsylvanian and early Permian, a number of pandemic genera appear to have immigrated into what is now North America. Stage 4 is restricted to the Upper Permian (late Leonardian-Guadalupian) strata and is characterized by short-ranging, stenotopic, provincial genera. The main causal factor controlling the four-stage evolution of late Paleozoic trilobites of the United States is interpreted to be eustacy. Whereas Stage 1 represents an adaptive radiation developed during the Lower Mississippian inundation of North America by the Kaskaskia Sequence, Stage 2 is present in strata deposited during the regression of the Kaskaskia sea. Stage 3 was formed during the transgression and stillstand of the Absaroka Sequence and, although initially endemic, Stage 3 faunas are strongly pandemic in the end when oceanic circulation patterns were at a maximum. A mid-Leonardian sea-level drop caused the extinction of Stage 3 fauna. Sea-level rise near the end of the Leonardian and into the Guadalupian created an adaptive radiation of stentopic species of Stage 4 that quickly became extinct with the latest Permian regression.

Assessment of the Coal-Bed Gas Total Petroleum System in the Cook Inlet-Susitna region, south-central Alaska

USGS Publications Warehouse

Rouse, William A.; Houseknecht, David W.

2012-01-01

The Cook Inlet-Susitna region of south-central Alaska contains large quantities of gas-bearing coal of Tertiary age. The U.S. Geological Survey in 2011 completed an assessment of undiscovered, technically recoverable coal-bed gas resources underlying the Cook Inlet-Susitna region based on the total petroleum system (TPS) concept. The Cook Inlet Coal-Bed Gas TPS covers about 9,600,000 acres and comprises the Cook Inlet basin, Matanuska Valley, and Susitna lowland. The TPS contains one assessment unit (AU) that was evaluated for coal-bed gas resources between 1,000 and 6,000 feet in depth over an area of about 8,500,000 acres. Coal beds, which serve as both the source and reservoir for natural gas in the AU, were deposited during Paleocene-Pliocene time in mires associated with a large trunk-tributary fluvial system. Thickness of individual coal beds ranges from a few inches to more than 50 feet, with cumulative coal thickness of more than 800 feet in the western part of the basin. Coal rank ranges from lignite to subbituminous, with vitrinite reflectance values less than 0.6 percent throughout much of the AU. The AU is considered hypothetical because only a few wells in the Matanuska Valley have tested the coal-bed reservoirs, so the use of analog coal-bed gas production data was necessary for this assessment. In order to estimate reserves that might be added in the next 30 years, coal beds of the Upper Fort Union Formation in the Powder River Basin of Wyoming and Montana were selected as the production analog for Tertiary coal beds in the Cook Inlet-Susitna region. Upper Fort Union coal beds have similar rank (lignite to subbituminous), range of thickness, and coal-quality characteristics as coal beds of the Tertiary Kenai Group. By use of this analog, the mean total estimate of undiscovered coal-bed gas in the Tertiary Coal-Bed Gas AU is 4.674 trillion cubic feet (TCF) of gas.

Seam profiling of three coals from Upper Cretaceous Menefee formation near Durango, CO

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pawlewicz, M.J.

1985-05-01

Column samples of three separate coal seams from the Upper Cretaceous Menefee Formation near Durango were examined with reflected light and oil immersion to characterize the vertical variation in the coal petrography. In order to interpret the paleoenvironments of the coal, the macerals (microlithotypes) that make up the coal were identified and their association (whether they are in microbands or dispersed throughout), their physical condition (if they show signs of weathering or transportation), and their modal composition were observed. The observed petrography indicates two main environments of deposition. Most of the microlithotypes are rich in vitrinite. This and the associationmore » and physical condition of the macerals indicate a terrestrial forest containing mainly woody plants and trees with a slightly fluctuating ground-water level. Less commonly, the microlithotypes have less vitrinite and more mineral matter, suggesting deposition in an open moor or deep water usually inhabited mainly be herbaceous plants. Macerals from both environments are weathered, suggesting infrequent dry periods or periods of lower water-table levels where the peat was exposed to subaerial oxidation.« less

Relations between coal petrology and gas content in the Upper Newlands Seam, Central Queensland, Australia

USGS Publications Warehouse

Walker, R.; Glikson, M.; Mastalerz, Maria

2001-01-01

The Upper Newlands Seam in the northern Bowen Basin, Queensland Australia consists of six benches (A-F) that have different petrographic assemblages. Benches C and E contain relatively abundant inertodetrinite and mineral matter, as well as anomalously high reflectance values; these characteristics support a largely allochthonous, detrital origin for the C and E benches. Fractures and cleats in the seam show a consistent orientation of northeast-southwest for face cleats, and a wide range of orientations for fractures. Cleat systems are well developed in bright bands, with poor continuity in the dull coal. Both maceral content and cleat character are suggested to influence gas drainage in the upper Newlands Seam. A pronounced positive correlation between vitrinite abundance and gas desorption data suggests more efficient drainage from benches with abundant vitrinite. Conversely, inertinite-rich benches are suggested to have less efficient drainage, and possibly retain gas within pore spaces, which could increase the outburst potential of the coal. ?? 2001 Elsevier Science B.V. All rights reserved.

Petrographic and geochemical contrasts and environmentally significant trace elements in marine-influenced coal seams, Yanzhou mining area, China

USGS Publications Warehouse

Liu, Gaisheng; Yang, P.; Peng, Z.; Chou, C.-L.

2004-01-01

The Yanzhou mining area in west Shandong Province, China contains coals of Permian and Carboniferous age. The 31 and 32 seams of the Permian Shanxi Formation and seams 6, 15-17 of the Carboniferous Taiyuan Formation were analyzed for coal petrology, mineralogy and geochemical parameters. The parameters indicate that the coal is high volatile bituminous in rank. The coal is characterized by high vitrinite and low to medium inertinite and liptinite contents. These properties may be related to evolution of the coal forming environment from more reducing conditions in a marine influenced lower delta plain environment for the early Taiyuan coals to more oxidizing paleoenvironments in an upper delta plain for the upper Shanxi coal seams. The major mineral phases present in the coal are quartz, kaolinite, pyrite and calcite. Sulfur is one of the hazardous elements in coal. The major forms of sulfur in coal are pyritic, organic and sulfate sulfur. Pyritic and organic sulfur generally account for the bulk of the sulfur in coal. Elemental sulfur also occurs in coal, but only in trace to minor amounts. In this paper, the distribution and concentration of sulfur in the Yanzhou mining district are analyzed, and the forms of sulfur are studied. The sulfur content of the Taiyuan coal seams is considerably higher than that of the Shanxi coals. Organic sulfur content is positively correlated to total and pyritic sulfur. The vertical variation of Cu, Zn, Pb, As, Th, U and sulfur contents in coal seam 3 of the Shanxi Formation in the Xinglongzhuang mine show that all these trace elements, with the exception of Th, are enriched in the top and bottom plies of the seam, and that their concentrations are also relatively high in the dirt bands within the seam. The pyritic sulfur is positively correlated with total sulfur, and both are enriched in the top, bottom and parting plies of the seam. The concentrations of the trace elements are closely related to sulfur and ash contents. Most of the trace elements are correlated with the ash content, and may be associated with the mineral matter in the coal. ?? 2004 Elsevier Ltd. All rights reserved.

Correlation chart of Pennsylvanian rocks in Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania showing approximate position of coal beds, coal zones, and key stratigraphic units

USGS Publications Warehouse

Ruppert, Leslie F.; Trippi, Michael H.; Slucher, Ernie R.

2010-01-01

This report contains a simplified provisional correlation chart that was compiled from both published and unpublished data in order to fill a need to visualize the currently accepted stratigraphic relations between Appalachian basin formations, coal beds and coal zones, and key stratigraphic units in the northern, central, and southern Appalachian basin coal regions of Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania. Appalachian basin coal beds and coal zones were deposited in a variety of geologic settings throughout the Lower, Middle, and Upper Pennsylvanian and Pennsylvanian formations were defined on the presence or absence of economic coal beds and coarse-grained sandstones that often are local or regionally discontinuous. The correlation chart illustrates how stratigraphic units (especially coal beds and coal zones) and their boundaries can differ between States and regions.

Meso-Cenozoic morphological evolution of NW Africa, the case of the Tuareg swell.

NASA Astrophysics Data System (ADS)

Rougier, S.; Gautheron, C.; Barbarand, J.; Missenard, Y.; Zeyen, H.; Pinna, R.; Bonin, B.; Liégeois, J.-P.; Ouabadi, A.; Frizon de Lamotte, D.

2012-04-01

The continental crust of Africa, largely built during the Pan-African orogeny (late Neoproterozoic) has acquired in its northern part, during Paleozoic times, an arch and basin morphology. Meso-Cenozoic large scale topographic anomalies, associated to Cenozoic intraplate volcanism, such as Hoggar, Tibesti or Darfur domes, are superimposed to these structures. Precise ages of swells, as well as their relations with Paleozoic arch and basin morphology of the area, remain controversial. The aim of this study, focussed on the Hoggar dome, in southern Algeria, is to produce new constraints on the Post-Paleozoic evolution of this region. The Tuareg shield, from which Hoggar is the main central part and Aïr a SE extension, forms a topographic high reaching an altitude >2900m (Mt Tahat, Atakor district), exposing Precambrian rocks over 500000km2. While presumed Cretaceous sedimentary remnants suggest a possible stage of slightly positive topography during the Mesozoic, current high topography is emphasized by Cenozoic volcanic formations, mostly basaltic in composition. We present new low-temperature thermochronology data, with apatite fission track and (U-Th)/He ages on Hoggar and Aïr substratum. We combine these results with thermal, gravimetric and isostatic two-dimensional lithosphere-scale geophysical models, following the method of Zeyen & Fernandez (1994). Preliminary thermochronological results present ages from 99+-6 to 166+-10 Myr for AFT, and AHe from 10 to 300 Myr. Thermal simulations of these data suggest that currently outcropping Precambrian Hoggar basement could have experienced temperatures of approximately 80°C between Upper Cretaceous and Eocene. We propose that these elevated temperatures are related to burial beneath a 1 to 3 km thick sedimentary cover, depending on thermal gradient. The base of this sedimentary cover could correspond to the poorly described Upper Cretaceous remnants, currently uplifted up to 1450 m. These results are in agreement with geophysical calculations showing that, when eliminating the topographical effect of lithosphere heating related to recent volcanism and assuming an Upper Cretaceous to Late Eocene thermally unperturbed lithosphere, a sedimentary basin may have existed. Up to 2 km of Cretaceous sediments could have been deposited on the Hoggar, confirming the thermochronological results. Ref: Zeyen, H. and M. Fernàndez (1994): Integrated lithospheric modeling combining thermal, gravity and local isostasy analysis: application to the NE Spanish Geotransect. J. Geophys. Res. 99: 18089-18102.

Methane in the Upper Silesian Coal Basin (Poland) - problem of reserves and exploitation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wojcik, A.J.

1995-08-01

The Upper Silesian Coal Basin (USCB) is the best recognized and the most productive coal basin in Poland. The USCB is primarily defined by the extent of Carboniferous coal-bearing formations. The sedimentary fill displays the stratigraphic record of major progressive inversion phases of the entire Moravo-Silesian basin during the late and post-geosynclinal period of the Variscan orogeny. According to the last estimates the coal reserves occurring above the depth limit of 1500 in are as follows: documented reserves - 58 billion tons, prognostic reserves - 46 billion tons, total - 104 billion tons. The coal type is predominantly vitrinitic, andmore » ash content is reported to be in the range of 11-17% and average sulphur content is 1.13%. The rank of USCB coal is largely controlled by complex coalification processes. It ranges from high volatile bituminous B, through medium volatile bituminous to high rank special coal semi anthracite and anthracite. The methane content of coal seams in USCB varies in a very broad range of 0-22 m{sup 3}/t coal (dry, ash free basis). The average gas content increases considerably within the depth range 600-1000 in from 0.99 to 4.68 m{sup 3}/t coal (daf). In deeper horizons it is more or less stable varying within the range of 4.7-7.0 m{sup 3}/t coal (daf). By this estimate, on average, the methane content is about 12,5 m{sup 3}/ton. There are several estimates of coal-bed methane resources in the USCB based on different methods. The resources are as follows: documented deposits in active mines to 1000 m: 370 BCM, undeveloped deposits to 1000 in: 340 BCM, deposit between 1000 and 1500 m: 590 BCM, total: 1300 BCM. The coalbed gas from this basin is primarily composed of saturated hydrocarbons and Nitrogen which amount to 97 volume percent. The rest is dominant by Carbon dioxide and Hydrogen.« less

Coal-type gas provinces in China and their geochemical characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Xiaobao; Xu Yonghang; Shen Ping

1996-12-31

The distribution of coal - type gases in China can be divided into the east gas province, the central gas province and the west gas province the east gas province lies in the East China Meso - Cenozoic Rift Belt, including Donghai Basin and Bohaiwan Basin. The ages of gas source rocks are Carbo - Permian and Tertiary. The types of gas reservoirs are a anticline or a hidden mountain - fault block combination reservoir. The CH{sub 4} content ofthe gases there is 83 -90%, with {delta}{sup 13}C{sub 1} -35.5 {approximately} -39.9{per_thousand}, and {delta}{sup 13}C{sub 2} -24.0 {approximately} -26.8{per_thousand}. Themore » {delta}{sup 13}C of condensate oils associated with the gases ranges from -25.4{per_thousand} to -26.8{per_thousand}. The central gas province is inside the Central China Paleozoic Plates, including Orclos Basin and Sichuan Basin. The gas source rocks are Carbo - Permian and Triassic. The types of gas reservoirs are an anticline-fault combination or a lithological-tectonic combination reservoir. The {delta}{sup 13}C{sub 1} of the gases there is -37.9 {approximately} -37. l{per_thousand}, with the {delta}{sup 13}C of condensate oil accompanying them - 25.1 {approximately} -26.6{per_thousand}. The west gas province is within the West China Late Paleozoic Intracontinental Compressive Belt, including Tarim Basin, Jungar Basin and Tuna Basin. The age of gas source rocks is Jurassic. The types of gas reservoirs are an anticline or an anticline-fault reservoir. The CH{sub 4} content of the gases there varies from 60 to 90%, with {delta}{sup 13}C{sub 1} from - 38.7 to -43.7{per_thousand} and {delta} {sup 13}C{sub 2} from -25.9{per_thousand} to -29.9{per_thousand}. The {delta} {sup 13}C of light oils and condensate oils accompanying the gases changes from 24.3{per_thousand} to 27.8{per_thousand}.« less

Coal-type gas provinces in China and their geochemical characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Xiaobao; Xu Yonghang; Shen Ping

1996-01-01

The distribution of coal - type gases in China can be divided into the east gas province, the central gas province and the west gas province the east gas province lies in the East China Meso - Cenozoic Rift Belt, including Donghai Basin and Bohaiwan Basin. The ages of gas source rocks are Carbo - Permian and Tertiary. The types of gas reservoirs are a anticline or a hidden mountain - fault block combination reservoir. The CH[sub 4] content ofthe gases there is 83 -90%, with [delta][sup 13]C[sub 1] -35.5 [approximately] -39.9[per thousand], and [delta][sup 13]C[sub 2] -24.0 [approximately] -26.8[permore » thousand]. The [delta][sup 13]C of condensate oils associated with the gases ranges from -25.4[per thousand] to -26.8[per thousand]. The central gas province is inside the Central China Paleozoic Plates, including Orclos Basin and Sichuan Basin. The gas source rocks are Carbo - Permian and Triassic. The types of gas reservoirs are an anticline-fault combination or a lithological-tectonic combination reservoir. The [delta][sup 13]C[sub 1] of the gases there is -37.9 [approximately] -37. l[per thousand], with the [delta][sup 13]C of condensate oil accompanying them - 25.1 [approximately] -26.6[per thousand]. The west gas province is within the West China Late Paleozoic Intracontinental Compressive Belt, including Tarim Basin, Jungar Basin and Tuna Basin. The age of gas source rocks is Jurassic. The types of gas reservoirs are an anticline or an anticline-fault reservoir. The CH[sub 4] content of the gases there varies from 60 to 90%, with [delta][sup 13]C[sub 1] from - 38.7 to -43.7[per thousand] and [delta] [sup 13]C[sub 2] from -25.9[per thousand] to -29.9[per thousand]. The [delta] [sup 13]C of light oils and condensate oils accompanying the gases changes from 24.3[per thousand] to 27.8[per thousand].« less

Use of saline water in energy development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Israelsen, C.E.; Adams, V.D.; Batty, J.C.

1980-06-01

Maps were made of the Upper Colorado River Basin showing locations of coal deposits, oil and gas, oil shale, uranium, and tar sand, in relationship to cities and towns in the area. Superimposed on these are locations of wells showing four ranges of water quality; 1000 to 3000 mg/l, 3000 to 10,000 mg/l, 10,000 to 35,000 mg/l, and over 35,000 mg/l. Information was assembled relative to future energy-related projects in the upper basin, and estimates were made of their anticipated water needs. Using computer models, various options were tested for using saline water for coal-fired power plant cooling. Both coolingmore » towers and brine evaporation ponds were included. Information is presented of several proven water treatment technologies, and comparisons are made of their cost effectiveness when placed in various combinations in the power plant makeup and blowdown water systems. A relative value scale was developed which compares graphically the relative values of waters of different salinities based on three different water treatment options and predetermined upper limits of cooling tower circulating salinities. Coal from several different mines was slurried in waters of different salinities. Samples were analyzed in the laboratory to determine which constituents had been leached from or absorbed by the coal, and what possible deleterious effects this might have on the burning properties of the coal, or on the water for culinary use or irrigation.« less

Textural and Rb-Sr isotopic evidence for late Paleozoic mylonitization within the Honey Hill fault zone southeastern Connecticut

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Hara, K.D.; Gromet, L.P.

A petrographic and Rb-Sr isotopic study of rocks within and near the Honey Hill fault zone places important constraints on its history of movement. Rb-Sr apparent ages for micas and plagioclase from these rocks have been reset and range from Permian to Triassic, considerably younger than the minimum stratigraphic age (Ordovician) of the rocks studied or of Acadian (Devonian) regional metamorphism. Permian Rb-Sr ages of dynamically recrystallized muscovite date the development of mylonite fabric. An older age is precluded by the excellent preservation of unrecovered quartz, which indicates that these rocks did not experience temperatures high enough to anneal quartzmore » or thermally reset Rb-Sr isotopic systems in muscovite since the time of mylonitization. Metamorphic mineral assemblages and mineral apparent ages in rocks north of the fault zone indicate recrystallization under similar upper greenschist-lower amphibolite grade conditions during Permian to Triassic time. Collectively these results indicate that the Honey Hill fault zone was active during the Late Paleozoic and that ductile deformation and metamorphism associated with the Alleghanian orogeny extend well into southern Connecticut. An Alleghanian age for mylonitization within the Honey Hill fault zone suggests it should be considered as a possible site for the major Late Paleozoic strike-slip displacements inferred from paleomagnetic studies for parts of coastal New England and maritime Canada.« less

Thin and layered subcontinental crust of the great Basin western north America inherited from Paleozoic marginal ocean basins?

USGS Publications Warehouse

Churkin, M.; McKee, E.H.

1974-01-01

The seismic profile of the crust of the northern part of the Basin and Range province by its thinness and layering is intermediate between typical continental and oceanic crust and resembles that of marginal ocean basins, especially those with thick sedimentary fill. The geologic history of the Great Basin indicates that it was the site of a succession of marginal ocean basins opening and closing behind volcanic arcs during much of Paleozoic time. A long process of sedimentation and deformation followed throughout the Mesozoic modifying, but possibly not completely transforming the originally oceanic crust to continental crust. In the Cenozoic, after at least 40 m.y. of quiescence and stable conditions, substantial crustal and upper-mantle changes are recorded by elevation of the entire region in isostatic equilibrium, crustal extension resulting in Basin and Range faulting, extensive volcanism, high heat flow and a low-velocity mantle. These phenomena, apparently the result of plate tectonics, are superimposed on the inherited subcontinental crust that developed from an oceanic origin in Paleozoic time and possibly retained some of its thin and layered characteristics. The present anomalous crust in the Great Basin represents an accretion of oceanic geosynclinal material to a Precambrian continental nucleus apparently as an intermediate step in the process of conversion of oceanic crust into a stable continental landmass or craton. ?? 1974.

Geochemical evaluation of upper cretaceous fruitland formation coals, San Juan Basin, New Mexico and Colorado

USGS Publications Warehouse

Michael, G.E.; Anders, D.E.; Law, B.E.

1993-01-01

Geochemical analyses of coal samples from the Upper Cretaceous Fruitland Formation in the San Juan Basin of New Mexico and Colorado were used to determine thermal maturity, type of kerogen, and hydrocarbon generation potential. Mean random vitrinite reflectance (%Rm) of the Fruitland coal ranges from 0.42 to 1.54%. Rock-Eval pyrolysis data and saturated to aromatic hydrocarbon ratio indicate that the onset of thermal hydrocarbon generation begins at about 0.60% Rm and peak generation occurs at about 0.85% Rm. Several samples have hydrogen index values between 200 and 400, indicating some potential for liquid hydrocarbon generation and a mixed Type III and II kerogen. Pentacyclic and tricyclic terpanes, steranes, aromatic steroids and methylphenanthrene maturity parameters were observed through the complete range of thermal maturity in the Fruitland coals. Aromatic pentacyclic terpanes, similar to those found in brown coals of Australia, were observed in low maturity samples, but not found above 0.80% Rm. N-alkane depleted coal samples, which occur at a thermal maturity of approx. 0.90% Rm, paralleling peak hydrocarbon generation, are fairly widespread throughout the basin. Depletion of n-alkanes in these samples may be due to gas solution stripping and migration fromthe coal seams coincident with the development of pressure induced fracturing due to hydrocarbon generation; however, biodegradation may also effect these samples. ?? 1993.

Variable deep structure of a midcontinent fault and fold zone from seismic reflection: La Salle deformation belt, Illinois basin

USGS Publications Warehouse

McBride, J.H.

1997-01-01

Deformation within the United States mid-continent is frequently expressed as quasilinear zones of faulting and folding, such as the La Salle deformation belt, a northwest-trending series of folds cutting through the center of the Illinois basin. Seismic reflection profiles over the southern La Salle deformation belt reveal the three-dimensional structural style of deformation in the lower Paleozoic section and uppermost Precambrian(?) basement. Individual profiles and structural contour maps show for the first time that the folds of the La Salle deformation belt are underlain at depth by reverse faults that disrupt and offset intrabasement structure, offset the top of interpreted Precambrian basement, and accommodate folding of overlying Paleozoic strata. The folds do not represent development of initial dips by strata deposited over a preexisting basement high. Rather, the structures resemble subdued "Laramide-style" forced folds, in that Paleozoic stratal reflectors appear to be flexed over a fault-bounded basement uplift with the basement-cover contact folded concordantly with overlying strata. For about 40 km along strike, the dominant faults reverse their dip direction, alternating between east and west. Less well expressed antithetic or back thrusts appear to be associated with the dominant faults and could together describe a positive flower structure. The overall trend of this part of the La Salle deformation belt is disrupted by along-strike discontinuities that separate distinct fold culminations. Observations of dual vergence and along-strike discontinuities suggest an original deformation regime possibly involving limited transpression associated with distant late Paleozoic Appalachian-Ouachita mountain building. Moderate-magnitude earthquakes located west of the western flank of the La Salle deformation belt have reverse and strike-slip mechanisms at upper trustai depths, which might be reactivating deep basement faults such as observed in this study. The La Salle deformation belt is not necessarily typical of other well-known major midcontinent fault and fold zones, such as the Nemaha ridge, over which Paleozoic and younger sediments appear to simply be draped.

Assessment of Appalachian basin oil and gas resources:Devonian shale - Middle and Upper Paleozoic Total Petroleum System

USGS Publications Warehouse

Milici, Robert C.; Swezey, Christopher S.

2006-01-01

The U.S. Geological Survey (USGS) recently completed an assessment of the technically recoverable undiscovered hydrocarbon resources of the Appalachian Basin Province. The assessment province includes parts of New York, Pennsylvania, Ohio, Maryland, West Virginia, Virginia, Kentucky, Tennessee, Georgia and Alabama. The assessment was based on six major petroleum systems, which include strata that range in age from Cambrian to Pennsylvanian. The Devonian Shale-Middle and Upper Paleozoic Total Petroleum System (TPS) extends generally from New York to Tennessee. This petroleum system has produced a large proportion of the oil and natural gas that has been discovered in the Appalachian basin since the drilling of the Drake well in Pennsylvania in 1859. For assessment purposes, the TPS was divided into 10 assessment units (plays), 4 of which were classified as conventional and 6 as continuous. The results were reported as fully risked fractiles (F95, F50, F5 and the Mean), with the fractiles indicating the probability of recovery of the assessment amount. Products reported were oil (millions of barrels of oil, MMBO), gas (billions of cubic feet of gas, BCFG), and natural gas liquids (millions of barrels of natural gas liquids, MMBNGL). The mean estimates for technically recoverable undiscovered hydrocarbons in the TPS are: 7.53 MMBO, 31,418.88 BCFG (31.42 trillion cubic feet) of gas, and 562.07 MMBNGL.

An in situ occurrence of coal balls in the Amburgy coal bed, Pikeville Formation (Duckmantian), central Appalachian Basin, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Chesnut, D.R.; Phillips, T.L.; Hower, J.C.

1999-01-01

Carbonate concretions containing permineralized peat, commonly called coal balls, were encountered in the Amburgy coal, a generally low-ash (9.4%), but commonly high-sulfur (3.6%), Middle Pennsylvanian coal of the Eastern Kentucky Coal Field. These are the first coal balls from the Amburgy coal, and one of only a few reported occurrences from the central Appalachian Basin. The coal balls occur in the upper part of the coal, between two paleochannel cut-outs at the top of the Pikeville Formation, and immediately beneath a scour with a marine fossil lag at the base of the Kendrick Shale Member, Hyden Formation. The coal is thickest (1.3 m) in a narrow (<300 m), elongate depression between the bounding paleochannels, and thins toward the occurrence of coal balls. Total biovolume as measured from acetate peels of coal balls indicates cordaites or lycopsid (36.1% each) dominance. Vertical sampling through one coal-ball aggregate shows zoning from a lower cordaites-dominant (88.7%) assemblage, to a middle, degraded, sphenopsid-rich assemblage, to an upper lycopsid-dominant (88.6%) assemblage. Beneath the coal balls, palynologic and petrographic analyses indicate the basal and middle portions of the bed are dominated by arborescent lycopsid spores and cordaites pollen, and by vitrinite macerals. The top part of the bed, above the coal balls, contains increased intertinite macerals, increased percentages of small fern spores, and variable ash yield (5-21%). Thickening of the Amburgy coal along a structural low, in combination with basal high-ash yields, vitrinite-dominance, and heterogenous palynoflora, indicate paleotopographic control on initial peat accumulation. Abundant lycopsid spores in the basal and middle part of the coal reflect rheotrophic conditions consistent with accumulation in a paleotopographic depression. Apparent zonation preserved in one of the coal-ball masses may document plant successions in response to flooding. Similar percentages of cordaites and lycopods, respectively, in the zones above and below the degraded incursion interval reflect development of a mixed, successional pattern in response to the flooding. Coal-ball formation may have been facilitated by channeling along the Kendrick ravinement, within a paleotopographic depression, at the split margin of the Amburgy peat, either through direct transmittal of carbonates and marine waters into the peat, or through degassing of the peat beneath the scour.

Early diagenetic high-magnesium calcite and dolomite indicate that coal balls formed in marine or brackish water: Stratigraphic and paleoclimatic implications

NASA Astrophysics Data System (ADS)

Raymond, Anne

2016-04-01

Coal balls are carbonate and pyrite permineralizations of peat that contain three-dimensional plant fossils preserved at the cellular level. Coal balls, which occur in Pennsylvanian and earliest Permian equatorial coals, provide a detailed record of terrestrial ecology and tropical climate during the Late Paleozoic Ice Age; yet their depositional environment remains controversial. The exquisite preservation of some coal-ball fossils, e.g. pollen with pollen tubes and leaves with mesophyll, indicates rapid formation. The presence of abundant, cement-filled, void spaces within and between the plant debris in most coal balls indicates that they formed in uncompacted peat, near the surface of the mire. Botanical, taphonomic and isotopic evidence point to a freshwater origin for coal balls. The nearest living relatives of coal ball plants (modern lycopsids, sphenopsids, marratialean ferns and conifers) grow in fresh water. Coal-ball peat contains a high percentage of aerial debris, similar to modern freshwater peat. The stable oxygen isotopes of coal-ball carbonate (δ18O = 16 to 3 per mil) suggest a freshwater origin. However, the widespread occurrence of marine invertebrates and early diagenetic framboidal pyrite in coal balls suggests that many formed in close proximity to marine water. Indeed, carbonate petrology points to a marine or brackish water origin for the first-formed carbonate cements in coal balls. Petrographic and geochemical (microprobe) analysis of coal-ball carbonates in Pennsylvanian coals from the midcontinent of North America (Western Interior Basin, West Pangaea) and the Ruhr and Donets Basins (East Pangaea) indicate that the first formed carbonate is either radaxial, nonstochiometric dolomite or high magnesium calcite (9 - 17 mol % MgCO3, indicating precipitation in marine or brackish water. Although both primary dolomite and high magnesium calcite can form in lacustrine settings, the lakes in which these minerals form occur in carbonate terranes and experience significant evaporation. Paleotropical coals with coal balls are under- and overlain by siliciclastic sediments, and, if fresh, would have required ever-wet climatic conditions for peat to accumulate. Pervasive freshwater diagenesis, with low magnesium calcite enveloping individual grains of high-magnesium calcite, results in most coal-ball carbonates having a freshwater or mixed isotopic signature. In some coal balls, cell walls in the root cortex (a soft tissue) separate carbonate of differing magnesium content, resulting in cells filled with low-magnesium (freshwater) calcite adjacent to cells filled with high-magnesium (marine) calcite, suggesting that these cements formed in recently dead or dying roots. The juxtaposition of high-magnesium (marine) calcite and low-magnesium (freshwater) calcite in coal balls suggests that they formed at the marine/freshwater interface in mires that contained salt-tolerant plants. This model of coal-ball formation suggests that coals bearing coal balls accumulated early in marine transgression as glaciers melted and sea level rose. In modern coastal mires, tidal incursion of salt water can maintain high freshwater tables, enabling domed freshwater peat to form in climates that normally would be too dry for tropical freshwater peat accumulation. Peat accumulation in these mires may be due to marine transgression rather than the ever-wet paleoclimates.

Synthesis of late Paleozoic and Mesozoic eolian deposits of the Western Interior of the United States

USGS Publications Warehouse

Blakey, R.C.; Peterson, F.; Kocurek, G.

1988-01-01

Late Paleozoic and Mesozoic eolian deposits include rock units that were deposited in ergs (eolian sand seas), erg margins and dune fields. They form an important part of Middle Pennsylvanian through Upper Jurassic sedimentary rocks across the Western Interior of the United States. These sedimentary rock units comprise approximately three dozen major eolian-bearing sequences and several smaller ones. Isopach and facies maps and accompanying cross sections indicate that most eolian units display varied geometry and complex facies relations to adjacent non-eolian rocks. Paleozoic erg deposits are widespread from Montana to Arizona and include Pennsylvanian formations (Weber, Tensleep, Casper and Quadrant Sandstones) chiefly in the Northern and Central Rocky Mountains with some deposits (Hermosa and Supai Groups) on the Colorado Plateau. Lower Permian (Wolfcampian) erg deposits (Weber, Tensleep, Casper, Minnelusa, Ingleside, Cedar Mesa, Elephant Canyon, Queantoweap and Esplanade Formations) are more widespread and thicken into the central Colorado Plateau. Middle Permian (Leonardian I) erg deposits (De Chelly and Schnebly Hill Formations) are distributed across the southern Colorado Plateau on the north edge of the Holbrook basin. Leonardian II erg deposits (Coconino and Glorieta Sandstones) are slightly more widespread on the southern Colorado Plateau. Leonardian III erg deposits formed adjacent to the Toroweap-Kaibab sea in Utah and Arizona (Coconino and White Rim Sandstones) and in north-central Colorado (Lyons Sandstone). Recognized Triassic eolian deposits include major erg deposits in the Jelm Formation of central Colorado-Wyoming and smaller eolian deposits in the Rock Point Member of the Wingate Sandstone and upper Dolores Formation, both of the Four Corners region. None of these have as yet received a modern or thorough study. Jurassic deposits of eolian origin extend from the Black Hills to the southern Cordilleran arc terrain. Lower Jurassic intervals include the Jurassic part of the Wingate Sandstone and the Navajo-Aztec-Nugget complex and coeval deposits in the arc terrain to the south and west of the Colorado Plateau. Major Middle Jurassic deposits include the Page Sandstone on the Colorado Plateau and the widespread Entrada Sandstone, Sundance Formation, and coeval deposits. Less extensive eolian deposits occur in the Carmel Formation, Temple Cap Sandstone, Romana Sandstone and Moab Tongue of the Entrada Sandstone, mostly on the central and western Colorado Plateau. Upper Jurassic eolian deposits include the Bluff Sandstone Member and Recapture Member of the Morrison Formation and Junction Creek Sandstone, all of the Four Corners region, and smaller eolian deposits in the Morrison Formation of central Wyoming and apparently coeval Unkpapa Sandstone of the Black Hills. Late Paleozoic and Mesozoic eolian deposits responded to changing climatic, tectonic and eustatic controls that are documented elsewhere in this volume. All of the eolian deposits are intricately interbedded with non-eolian deposits, including units of fluvial, lacustrine and shallow-marine origin, clearly dispelling the myth that eolian sandstones are simple sheet-like bodies. Rather, these units form some of the most complex bodies in the stratigraphic record. ?? 1988.

Geology and coal resources of the Stonewall-Tercio area, Las Animas County, Colorado

USGS Publications Warehouse

Wood, Gordon H.; Johnson, R.B.; Eargle, D.H.; Duffner, R.T.; Major, Harold

1951-01-01

The Stonewall-Tercio area lies along the western edge of the Trinidad coal field, Colorado, a part of the large Raton Mesa region of Colorado and New Mexico. Coal of Upper Cretaceous and early Tertiary age in that region has been utilized extensively for coking and for domestic heating. Present mining operations are limited, but mining is possible throughout much of the field.

ORIGIN OF QUARTZ IN COAL.

USGS Publications Warehouse

Ruppert, Leslie F.; Cecil, C. Blaine; Stanton, Ronald W.

1984-01-01

Both a scanning electron microscope and an electron microprobe (EMP) were used in this study to analyze the cathodoluminescence properties of quartz grains in samples of the Upper Freeport coal bed because quartz grains in coal are small (silt sized) and below the resolution capabilities of a standard luminoscope. Quartz grains were identified by the detection of silicon alone with energy dispersive X-ray units attached to both the SEM and the EMP.

Remote sensing of coal mine pollution in the upper Potomac River basin

NASA Technical Reports Server (NTRS)

1974-01-01

A survey of remote sensing data pertinent to locating and monitoring sources of pollution resulting from surface and shaft mining operations was conducted in order to determine the various methods by which ERTS and aircraft remote sensing data can be used as a replacement for, or a supplement to traditional methods of monitoring coal mine pollution of the upper Potomac Basin. The gathering and analysis of representative samples of the raw and processed data obtained during the survey are described, along with plans to demonstrate and optimize the data collection processes.

Remedial investigation report on Chestnut Ridge Operable Unit 2 (filled coal ash pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 2: Appendixes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-08-01

This report comprises appendices A--J which support the Y-12 Plant`s remedial action report involving Chestnut Ridge Operable Unit 2 (filled coal ash pond/Upper McCoy Branch). The appendices cover the following: Sampling fish from McCoy Branch; well and piezometer logs; ecological effects of contaminants in McCoy Branch 1989-1990; heavy metal bioaccumulation data; microbes in polluted sediments; and baseline human health risk assessment data.

Rare earth elements in fly ashes created during the coal burning process in certain coal-fired power plants operating in Poland - Upper Silesian Industrial Region.

PubMed

Smolka-Danielowska, Danuta

2010-11-01

The subject of the study covered volatile ashes created during hard coal burning process in ash furnaces, in power plants operating in the Upper Silesian Industrial Region, Southern Poland. Coal-fired power plants are furnished with dust extracting devices, electro precipitators, with 99-99.6% combustion gas extracting efficiency. Activity concentrations ofTh-232, Ra-226, K-40, Ac-228, U-235 and U-238 were measured with gamma-ray spectrometer. Concentrations of selected rare soil elements (La, Ce, Nd, Sm, Y, Gd, Th, U) were analysed by means of instrumental neutron activation analysis (INAA). Mineral phases of individual ash particles were identified with the use of scanning electron microscope equipped with EDS attachment. Laser granulometric analyses were executed with the use of Analyssette analyser. The activity of the investigated fly-ash samples is several times higher than that of the bituminous coal samples; in the coal, the activities are: 226Ra - 85.4 Bq kg(-1), 40 K-689 Bq kg(-1), 232Th - 100.8 Bq kg(-1), 235U-13.5 Bq kg(-1), 238U-50 Bq kg(-1) and 228Ac - 82.4 Bq kg(-1).

Thrust-ridge paleodepositional model for the Upper Freeport coal bed and associated clastic facies, Upper Potomac coal field, Appalachian Basin, U.S.A.

USGS Publications Warehouse

Belt, Edward S.; Lyons, P.C.

1990-01-01

Two differential depositional sequences are recognized within a 37-m-thick lowermost section of the Conemaugh Group of Late Pennsylvanian (Westphalian D) age in the southern part of the Upper Potomac coal field (panhandle of Maryland and adjacent West Virginia). The first sequence is dominated by the Upper Freeport coal bed and zone (UF); the UF consists of a complex of interfingered thick coal beds and mudrocks. The UF underlies the entire 500 km2 study area (approximately 40 km in a NE-SW direction). The second sequence is dominated by medium- to coarse-grained sandstone and pebbly sandstone. They were deposited in channel belts that cut into and interfingered laterally with mudrock and fine- to medium-grained sandstone facies of floodbasin and crevasse-lobe origin. Thin lenticular coals occur in the second sequence. Nowhere in the study area does coarse-grained sandstone similar to the sandstone of the channel belts of the second sequence occur within the UF. However, 20 km north of the study area, coarse channel belts are found that are apparently synchronous with the UF (Lyons et al., 1984). The southeastern margin of the study are is bounded by the Allegheny Front. Between it and the North Mountain thrust (75 km to the southeast), lie at least eight other thrusts of unknown extent (Wilson, 1887). All these thrusts are oriented northwest; Devonian and older strata are exposed at the surface between the Allegheny Front and the North Mountain thrust. A blind-thrust ridge model is proposed to explain the relation of the two markedly depositional sequences to the thrusts that lie to the southeast of the Upper Potomac coal field. This model indicates that thrust ridges diverted coarse clastics from entering the swamp during a period when the thick Upper Freeport peat accumulated. Anticlinal thrust ridges and associated depressions are envisioned to have developed parallel to the Appalachian orogen during Middle and early Late Pennsylvanian time. A blind thrust developed from one of the outboard ridges, and it was thrust farther outboard ahead of the main body of the orogen. Sediment derived from the orogen was diverted into a sediment trap inboard of the ridge (Fig. 1). The ridge prevented sediment from entering the main peat-forming swamp. Sediment shed from the orogen accumulated in the sediment trap was carried out of the ends of the trap by steams that occupied the shear zone at the ends of the blind-thrust ridge (Fig. 1). Remnants of blind-thrust ridges occurs in the Sequatchie Valley thrust and the Pine Mountain thrust of the southern Appalachians. The extent, parallel to the orogen, of the thick areally extensive UF coal is related to the length of the blind-thrust ridge that, in turn, controlled the spacing of the river-derived coarse clastics that entered the main basin from the east. Further tectonism caused the thrust plane to emerge to the surface of the blind-thrust ridge. Peat accumulation was then terminated by the rapid erosion of the blind-thrust ridge and by the release of trapped sediment behind it. The peat was buried by sediments from streams from closely spaced channel belts] with intervening floodbasins. The model was implications for widespread peat (coal) deposits that developed in tropical regions, a few hundred kilometers inland from the sea during Pennsylvanian time (Belt and Lyons, 1989). ?? 1990.

The impact of the structural features of the rock mass on seismicity in Polish coal mines

NASA Astrophysics Data System (ADS)

Patyńska, Renata

2017-11-01

The article presents seismic activity induced in the coal mines of the Upper Silesian Coal Basin (GZW) in relation to the locations of the occurrence of rockbursts. The comparison of these measurements with the structural features of the rock mass of coal mines indicates the possibility of estimating the so-called Unitary Energy Expenditure (UEE) in a specific time. The obtained values of UEE were compared with the distribution of seismic activity in GZW mines. The level of seismic activity in the analysed period changed and depended on the intensity of mining works and diverse mining and geological conditions. Five regions, where tremors occurred (Bytom Trough, Main Saddle, Main Trough, Kazimierz Trough, and Jejkowice and Chwałowice Trough) which belong to various structural units of the Upper Silesia were analyzed. It was found out that rock bursts were recorded only in three regions: Main Saddle, Bytom Trough, and Jejkowice and Chwałowice Trough.

Use of saline water in energy development. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Israelsen, C.E.; Adams, V.D.; Batty, J.C.

1980-06-01

Information was assembled relative to future energy-related projects in the upper basin, and estimates were made of their anticipated water needs. Using computer models, various options were tested for using saline water for coal-fired power plant cooling. Both cooling towers and brine evaporation ponds were included. Information is presented of several proven water treatment technologies, and comparisons are made of their cost effectiveness when placed in various combinations in the power plant makeup and blowdown water systems. A relative value scale was developed which compares graphically the relative values of waters of different salinities based on three different water treatmentmore » options and predetermined upper limits of cooling tower circulating salinities. Coal from several different mines was slurried in waters of different salinities. Samples were analyzed in the laboratory to determine which constituents had been leached from or absorbed by the coal, and what possible deleterious effects this might have on the burning properties of the coal, or on the water for culinary use or irrigation.« less

Formation of most of our coal brought Earth close to global glaciation

PubMed Central

2017-01-01

The bulk of Earth’s coal deposits used as fossil fuel today was formed from plant debris during the late Carboniferous and early Permian periods. The high burial rate of organic carbon correlates with a significant drawdown of atmospheric carbon dioxide (CO2) at that time. A recent analysis of a high-resolution record reveals large orbitally driven variations in atmospheric CO2 concentration between ∼150 and 700 ppm for the latest Carboniferous and very low values of 100 ± 80 ppm for the earliest Permian. Here, I explore the sensitivity of the climate around the Carboniferous/Permian boundary to changes in Earth’s orbital parameters and in atmospheric CO2 using a coupled climate model. The coldest orbital configurations are characterized by large axial tilt and small eccentricities of Earth’s elliptical orbit, whereas the warmest configuration occurs at minimum tilt, maximum eccentricity, and a perihelion passage during Northern hemisphere spring. Global glaciation occurs at CO2 concentrations <40 ppm, suggesting a rather narrow escape from a fully glaciated Snowball Earth state given the low levels and large fluctuations of atmospheric CO2. These findings highlight the importance of orbital cycles for the climate and carbon cycle during the late Paleozoic ice age and the climatic significance of the fossil carbon stored in Earth’s coal deposits. PMID:29073052

Assessment of Appalachian Basin Oil and Gas Resources: Carboniferous Coal-bed Gas Total Petroleum System

USGS Publications Warehouse

Milici, Robert C.

2004-01-01

The Carboniferous Coal-bed Gas Total Petroleum System, lies within the central and northern parts of the Appalachian coal field. It consists of five assessment units (AU): the Pocahontas Basin in southwestern Virginia, southern West Virginia, and eastern Kentucky, the Central Appalachian Shelf in Tennessee, eastern Kentucky and southern West Virginia, East Dunkard (Folded) in western Pennsylvania and northern West Virginia, West Dunkard (Unfolded) in Ohio and adjacent parts of Pennsylvania and West Virginia, and the Appalachian Anthracite and Semi-Anthracite AU in Pennsylvania and Virginia. Of these, only the Pocahontas Basin and West Dunkard (Folded) AU were assessed quantitatively by the U.S. Geological survey in 2002 as containing about 3.6 and 4.8 Tcf of undiscovered, technically recoverable gas, respectively (Milici and others, 2003). In general, the coal beds of this Total Petroleum System, which are both the source rock and reservoir, were deposited together with their associated sedimentary strata in Mississippian and Pennsylvanian (Carboniferous) time. The generation of biogenic (microbial) gas probably began almost immediately as the peat deposits were first formed. Microbial gas generation is probably occurring at present to some degree throughout the basin, where the coal beds are relatively shallow and wet. With sufficient depth of burial, compaction, and coalification during the late Paleozoic and Early Mesozoic, the coal beds were heated sufficiently to generate thermogenic gas in the eastern part of the Appalachian basin. Trap formation began initially with the deposition of the paleopeat deposits during the Mississippian, and continued into the Late Pennsylvanian and Permian as the Appalachian Plateau strata were deformed during the Alleghanian orogeny. Seals are the connate waters that occupy fractures and larger pore spaces within the coal beds as well as the fine-grained siliciclastic sedimentary strata that are intercalated with the coal. The critical moment for the petroleum system occurred during this orogeny, when deformation created geologic structures in the eastern part of the basin that enhanced fracture porosity within the coal beds. In places, burial by thrust sheets (thrust loading) within the Appalachian fold-and-thrust belt may have resulted in additional generation of thermogenic CBM in the anthracite district of Pennsylvania and in the semianthracite deposits of Virginia and West Virginia.

The geology and palynology of lower and Middle Pennsylvanian strata in the Western Kentucky Coal Field

USGS Publications Warehouse

Eble, C.F.; Greb, S.F.; Williams, D.A.

2001-01-01

The Western Kentucky Coal Field is the southern tip of the Eastern Interior, or Illinois Basin. Pennsylvanian rocks in this area, which include conglomerate, sandstone, shale, limestone and coal, were deposited primarily in coastal-deltaic settings at a time when western Kentucky was located close to the equator. This paper discusses temporal changes in regional sedimentation patterns and coal-forming floras of Lower and Middle Pennsylvanian strata in the Western Kentucky Coal Field. Lower Pennsylvanian strata of the Caseyville Formation are characterized by paleovalley-filling sedimentation patterns and extabasinal quartz pebbles. Caseyville Formation coals are characterized thin and discontinuous and were strongly influenced by subsidence within underlying paleovalleys, and the dissected lower Pennsylvanian paleotopography. Caseyville coals are commonly dominated by Lycospora, but can also have variable palynofloras, which probably reflects variable edaphic conditions and edge effects within small, patchy paleomires. Tradewater Formation strata show increased marine influences and tidal-estuarine sedimentation, especially in the middle and upper parts. Coal beds in the lower part of the Tradewater typically are thin and discontinuous, although some economically important beds are present. Coals become thicker, more abundant and more laterally persistent towards the top of the formation. Palynologically, lower and middle Tradewater Formation coals are dominated by Lycospora, but begin to show increased amounts of tree fern spores. Middle and upper Tradewater coals are thicker and more continuous, and contain high percentages of tree fern spores. In addition, cordaite pollen is locally abundant in this interval. Carbondale and Shelburn (Desmoinesian) strata are much more laterally continuous, and occur within classic cyclothems that can be traced across the coal field. Cyclothems have long been interpreted as being eustatically driven, and glacio-eustacy controlled not only sedimentation but also the formation of Desmoinesian paleomires. Palynologically, Carbondale and Shelburn coals are either dominated by Lycospora or have heterogeneous palynofloras. Palynologic and coal-quality data suggest that hydrologic base level may have been the primary control on Desmoinesian paleomires, rather than paleoclimate, as the coals display rheotrophic, rather than ombrotrophic characteristics. ?? 2001 Elsevier Science B.V. All rights reserved.

Geologic, geotechnical, and geophysical properties of core from the Acme Fire-Pit-1 drill hole, Sheridan County, Wyoming

USGS Publications Warehouse

Collins, Donley S.

1983-01-01

A preliminary core study from the Acme Fire-Pit-1 drill hole, Sheridan County, Wyoming, revealed that the upper portion of the core had been baked by a fire confined to the underlying Monarch coal bed. The baked (clinkered) sediment above the Monarch coal bed was determined to have higher point-load strength values (greater than 2 MPa) than the sediment under the burned coal

Low ash, planar peat swamp development in an alluvial plain setting: The No. 5 block beds of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1992-01-01

Coals from the No. 5 Block beds (Westphalian D) are noted for their low ash and sulfur content. Beds are multiple benched, with rock partings separating individual benches. Benches have limited continuity and, where thick are dominated by bright, high ash coal at the base and dull, low ash coal in their upper portions. The duller coals contain more exinite and inertinite group macerals than the brighter coals. The depositional setting is an alluvial plain environment with channel systems separated by distances of about 20 km. The channel systems were flanked by clastic swamps for distances of up to 7more » km or more on either side. Areas of flood plain most distant from the channels were sites where peat accumulated and these zones were about 8 km across. High energy, low frequency flood events introduced fine grained sediment into the peat swamps resulting in thin layers of sediment being deposited on top of the peat. These sediment layers are thicker in areas where the underlying coal is the thickest. These thick coal areas are topographically negative. This relationship between coal and parting thickness and topography indicates that these peat swamps were low-lying or planar. Individual coal benches contain abundant amounts of preserved cellular tissue (telocollinite, semifusinite, fusinite) at most locations indicating that woody arborescent like vegetation was widespread in the swamps suggesting a planar morphology. The high concentrations of exinite and inertinite group macerals found in the upper portions of individual benches resulted from decomposition and oxidation of the peat in subaerial to aquatic planar swamp environments.« less

A drowned lycopsid forest above the Mahoning coal (Conemaugh Group, Upper Pennsylvanian) in eastern Ohio, U.S.A

USGS Publications Warehouse

DiMichele, W.A.; Eble, C.F.; Chaney, D.S.

1996-01-01

Over 800 mud-filled casts of upright lycopsid tree stumps have been documented immediately above the Mahoning coal in an active underground mine located in northwestern Jefferson County, Ohio. The coal body originated as a pod-shaped peat body of ??? 60 km2. Trees are rooted at several levels within a thin (15-40 cm) bone coal directly above the banded coal; they extend upward up to 15 cm into overlying, flat-bedded, carbonaceous mudstones that coarsen up. From a maximum basal diameter of 1.2 m, stumps taper upward to diameters no less than 0.3 m. Within single-entry transects, < 6 m wide that total 2585 m in length, stumps are randomly distributed. The trees are identified as lepidodendrids on the basis of gross morphology, external stem patterns, and attached stigmarian root systems, and provisionally as Lepidophloios or Lepidodendron by associated palynology of the enclosing matrix. Palynological analyses of incremental seam samples indicate an initial dominance of lycopsid spores with lepidodendracean affinities (Lycospora granulata from Lepidophloios hallii), replaced upwards by tree-fern spores, with a reoccurrence of lepidodendracean spores in the upper benches; spores of Sigillaria (Crassispora) are abundant only at the base of the coal. Petrographic analyses indicate a parallel trend from vitrinite-rich to inertinite- and liptinite-rich upward in the coal body. All data indicate that the peat represented by the Mahoning coal was drowned slowly. During the earliest stages of inundation, a lycopsid forest was re-established, only to be subsequently drowned.

Ecological persistence in the Late Mississippian (Serpukhovian, Namurian A) Megafloral record of the Upper Silesian Basin, Czech Republic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gastaldo, R.A.; Purkynova, E.; Simunek, Z.

2009-05-15

The Serpukhovian (Namurian A) stratigraphy of the Ostrava Formation, Upper Silesian Coal Basin, Czech Republic, consists of coal-bearing paralic sediments underlain by marine deposits in a cyclothemic nature similar to those in the Pennsylvanian of Euramerica. The thickness of the formation exceeds 3000 m, in which >170 coals are identified in a foreland basin setting. Fifty-five genetic cycles are identified in the present study, using transgressional erosional surfaces as lower and upper boundaries. Terrestrial plant-macrofossil assemblages are preserved within each cycle, mostly associated with coals, and these represent a sampling of the coastal plain vegetation. New high-precision isotope dilution-thermal ionizationmore » mass spectrometry U-Pb ages on zircons from tonsteins of two coals provide chronometric constraints for the Serpukhovian. Unweighted Pair Group Method with Arithmetic Mean clustering and Bayesian statistical classification group macrofloral assemblages into four distinct stratigraphic clusters, with assemblages persisting for <18 cycles before compositional change. Cycle duration, based on Ludmila (328.84{+-}0.16 Ma) and Karel (328.01{+-}0.08 Ma) tonsteins, overlaps the short-period (100 kyr) eccentricity cycle at the 95% confidence interval. These dates push the beginning of the Serpukhovian several million years deeper in time. An estimate for the Visean-Serpukhovian boundary is proposed at similar to 330 Ma. Late Mississippian wetland ecosystems persisted for >1.8 million years before regional perturbation, extirpation, or extinction of taxa occurred. Significant changes in the composition of macrofloral clusters occur across major marine intervals.« less

Ecological response of plant consumers to Middle-Upper Pennsylvanian extinctions in Illinois Basin coal swamps: Evidence from plant/arthropod interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Labandeira, C.; Phillips, T.

1992-01-01

Paleobotanical studies of coal-swamp vegetation during the Middle to Upper Pennsylvanian of North America indicate major changes from lycopsid dominated to tree-fern dominated coal-swamp forests as a result of extinction. This taxonomic shift from lycopsids to tree ferns should have implications on dependent feeding guilds, such as detritivores and herbivores. Comparative coal-ball evidence from the Springfield and Herrin Coals (Carbondale Fm.) and Calhoun Coal (Mattoon Fm.) is used to address this issue. The two major feeding guilds of Pennsylvanian coal-swamps were detritivores and herbivores. Detritivores were dominant throughout the interval. Evidence suggests an increasing presence of herbivores during the Desmoinesianmore » and especially during the Missourian. Based on identifications of tissue types found in coprolite types and plant tissue damage patterns, detritivores such as oribatid mites and an unknown stem-parenchyma consumer of Psaronius tree ferns occur before and after the extinction. Based on available evidence, detritivores apparently exhibited stability, particularly since the taxonomic affiliation of their food resource shifted considerably, thus indicating dietary specificities based instead on tissue type. There is evidence for herbivory by stem-miners on Missourian age tree-fern petioles; this distinctive behavior has not been reported for Desmoinesean or older deposits. The arthropod body-fossil record is consistent with this pattern: detritivore groups such as roaches survive the extinction largely intact, whereas other groups such as diverse protorthopterans,'' some of which were most likely herbivorous, experienced a significant extinction.« less

Cleat development in coals of the Upper Cretaceous Mesaverde Formation, Pilot Butte area, Wind River Reservation, Wyoming

USGS Publications Warehouse

Johnson, R.C.; Clark, A.C.; Szmajter, R.J.

1993-01-01

The cleat system developed in low-rank (mean viltrinite reflectance of 0.43 to 0.5 percent) coal beds in the Upper Cretaceous Mesaverde Formation was studied in outcrop and in coreholes drilled for coalbed methane evaluation near Pilot Butte in the central part of the Wind River Reservation. Cleats are the principal permeability pathway for fluids in coal beds. As a result, coalbed gas cannot be economically produced without significant cleat development. Two drillholes about 800 ft (244 m) apart encountered Mesaverde coal beds at depths ranging from 307 to 818 ft (93.6 to 249.3 m). One of the coal beds penetrated while drilling, the lowest coal in the Mesaverde coaly interval, is well exposed about a mile south of the two drillholes and the cleat development in this coal bed on outcrop was compared with that of the same coal in the drillholes.The 3 in (7.62 cm) diameter core is less than ideal for this study because cleat spacing in low-rank coals such as these typically averages greater than 7.62 cm. Nonetheless, face cleats at spacing of from 0.25 to 2.5 cm was observed in many of the coal beds. Cleats were less well-developed in other coal beds and no cleats were observed in a few beds. As expected, butt cleats were somewhat less well-developed than the face cleats. Attempts to relate cleat spacing to gas content, bed thickness, and ash content were not successful. A 3.0 m by 1.8 m area of the upper surface of the coal bed exposed a mile south of the drillsites was cleaned off and studied in detail. Cleat development in this limited study area varied from well-developed face and butt cleats in some places to few or no cleats in others. Face cleats trended roughly perpendicular to the fold axis of the nearby Pilot Butte anticline. Cleats did not penetrate a 2.5 cm thick carbonaceous shale bed about 20 cm above the base of the coal bed indicating that thin carbonaceous shale beds will act a permeability barriers. Two types of face cleats were observed on outcrop: 1) major face cleats that could be traced for as much as a meter along outcrop and averaged as little as 1.6 cm apart; and 2) microfractures or microcleats which paralleled the face cleats but averaged from 0.10 to 0.17 cm apart. The microcleats were more visible on outcrop than in core because of surface weathering which dried out the coal causing the microcleats to open up. This surface weathering also increased the aperture widths on many of the major cleats, and no attempt was made to systematically study aperture widths. These microcleats may contribute significantly to the permeability of the coals in the subsurface. Dewatering of the coal during the early stages of coalbed methane production may help open these microcleats thereby increasing permeability, and hence coalbed gas production, with time.

Fuel Gas Demonstration Plant Program: Small-Scale Industrial Project. Coal procurement activities. Technica report No. 9

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-04-14

This report consists of reference material taken from Erie Mining Company project files and includes the following: (1) Investigation of the Main Coal Producing Fields in the United States: This report identifies potential coal fiels for gasifier feedstock and factors influencing coal selection. The report analyzes coal fields located in five separate regions of the United States. Three design coals are discussed and lab reports have been included. Also included are cost considerations for selected coals and preliminary cost data and transportation routing. (2) Analysis of Test Coals Received at Erie Mining Company: Rosebud, Clarion, and Clarion-Brookfield-Kittaning coal samples weremore » received and analyzed at Erie Mining Company. The screen analysis indicated the severe decrepitation of the Rosebud western coal. (3) Criteria for Gasifier Coal: In this study, BCI states that gasifier feed should have the following characteristics: (1) the ratio between the upper and lower size for coal should be 3:1; (2) coal fines should not exceed 10%; (3) coal grading limits which can be handled are maximum range 3'' x 1'', minimum range - 1 1/2'' x 1/2''.« less

Field evidences for a Mesozoic palaeo-relief through the northern Tianshan

NASA Astrophysics Data System (ADS)

Gumiaux, Charles; Chen, Ke; Augier, Romain; Chen, Yan; Wang, Qingchen

2010-05-01

The modern Tianshan mountain belt, located in Central Asia, offers a natural laboratory to study orogenic processes linked with convergent geodynamical settings. Most of the previous studies either focused on the Paleozoic evolution of the range - subductions, arc accretions and continental collision - or on its Cenozoic intra-continental evolution linked with the India-Asia collision. At first order, the finite structure of this range obviously displays a remarkable uprising of Paleozoic "basement" rocks - as a crustal-scale ‘pop-up' - surrounded by two Cenozoic foreland basins. The present-day topography of the Tianshan is traditionally related to the latest intra-continental reactivation of the range. In contrast, the present field study of the northern Tianshan brings new and clear evidences for the existence of a significant relief, in this area, during Mesozoic times. The investigation zone is about 250 km long, from Wusu to Urumqi, along the northern flank of the Tianshan where the rivers deeply incised the topography. In such valleys, lithologies and structural relationships between Paleozoic basement rocks, Mesozoic and Cenozoic sedimentary series are particularly well exposed along several sections. Jurassic series are mostly characterized by coal-bearing, coarse-grained continental deposits. Within intra-mountain basins, sedimentary breccias, with clasts of Carboniferous basement rocks, have been locally found at the base of the series. This argues for the presence of a rather proximal palaeo-relief of basement rocks along the range front and the occurrence of proximal intra-mountain basins, during the Jurassic. Moreover, while a major thrust is mostly evoked between Jurassic deposits and the Paleozoic units, some of the studied sections show that the Triassic to Jurassic sedimentary series can be followed from the basin to the range. In these cases, the unconformity of the Mesozoic series on top of the Carboniferous basement has been locally clearly identified quite high in the mountain range or even, surprisingly, directly along the northern Tianshan "front" itself. Combining available information from geological maps, field investigations and numerous drilling wells, regional-scale cross-sections have been built. Some of them show "onlap" type deposit of the Triassic to Jurassic clastic sediments on top of the Paleozoic basement that was thus significantly sloping down to the North at that time. Our study clearly evidences, at different scales, the existence of a major palaeo-relief along the northern Tianshan range during Mesozoic, and particularly during Jurassic times. Such results are compatible with previous fission tracks and sedimentology studies. From this, the Tianshan's uplift and the movements associated with along its northern front structures, which are traditionally assigned to its Cenozoic reactivation, must be reduced. These new results question on the mode and timing of reactivation of structures and on the link between topography and intra-continental collisional settings.

An Impact of Mechanical Stress in Coal Briquettes on Sorption of Carbon Dioxide

NASA Astrophysics Data System (ADS)

Wierzbicki, Mirosław

2017-09-01

The presence of gases (methane or carbon dioxide) in hard coal is connected with numerous threats for miners employed in underground mining facilities. When analyzing the coal-methane system, it is necessary to determine the relationship between pressure and gas sorption. Such a relationship should be determined under conditions similar to the natural ones - when it comes to both temperature and pressure. The present paper discusses the results of research conducted with the use of coal briquettes under the state of mechanical stress. Carbon dioxide sorption isotherms were determined for different values of stress affecting the coal material. For five coal samples collected in different mines of the Upper Silesian Coal Basin, Langmuir's sorption isotherms were determined. The results point to significant impact that mechanical stress has upon the sorption process. It is about 1 percent of the value obtained for coal not subjected to stress per 1 MPa. The research results can also prove useful when analyzing hard coal seams from the perspective of their carbon dioxide sequestration abilities.

Paleozoic oil/gas shale reservoirs in southern Tunisia: An overview

NASA Astrophysics Data System (ADS)

Soua, Mohamed

2014-12-01

During these last years, considerable attention has been given to unconventional oil and gas shale in northern Africa where the most productive Paleozoic basins are located (e.g. Berkine, Illizi, Kufra, Murzuk, Tindouf, Ahnet, Oued Mya, Mouydir, etc.). In most petroleum systems, which characterize these basins, the Silurian played the main role in hydrocarbon generation with two main 'hot' shale levels distributed in different locations (basins) and their deposition was restricted to the Rhuddanian (Lllandovery: early Silurian) and the Ludlow-Pridoli (late Silurian). A third major hot shale level had been identified in the Frasnian (Upper Devonian). Southern Tunisia is characterized by three main Paleozoic sedimentary basins, which are from North to South, the southern Chotts, Jeffara and Berkine Basin. They are separated by a major roughly E-W trending lower Paleozoic structural high, which encompass the Mehrez-Oued Hamous uplift to the West (Algeria) and the Nefusa uplift to the East (Libya), passing by the Touggourt-Talemzane-PGA-Bou Namcha (TTPB) structure close to southern Tunisia. The forementioned major source rocks in southern Tunisia are defined by hot shales with elevated Gamma ray values often exceeding 1400 API (in Hayatt-1 well), deposited in deep water environments during short lived (c. 2 Ma) periods of anoxia. In the course of this review, thickness, distribution and maturity maps have been established for each hot shale level using data for more than 70 wells located in both Tunisia and Algeria. Mineralogical modeling was achieved using Spectral Gamma Ray data (U, Th, K), SopectroLith logs (to acquire data for Fe, Si and Ti) and Elemental Capture Spectroscopy (ECS). The latter technique provided data for quartz, pyrite, carbonate, clay and Sulfur. In addition to this, the Gamma Ray (GR), Neutron Porosity (ΦN), deep Resistivity (Rt) and Bulk Density (ρb) logs were used to model bulk mineralogy and lithology. Biostratigraphic and complete geochemical review has been undertaken from published papers and unpublished internal reports to better assess these important source intervals.

Carboniferous paleogeographic and paleoclimatic reconstructions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scotese, C.R.; Raymond, A.

1992-01-01

The Carboniferous was an important transitional period in earth history. The Paleozoic oceans separating the continents of Gondwana, Laurentia, Baltica, Kazakhstan, and Siberia had closed by the late Carboniferous forming the late Paleozoic supercontinent of Pangea. Plate motions which appear to have been rapid during the Early Carboniferous (6--10 cm/yr), slowed to a temperature gradient increased as the Earth's climate changed from hot-house to ice-house conditions. Sea level, which stood high during the Early Carboniferous, fell as a result of continental collision and mountain-building, and then began to rise and fall rhythmically as the South Polar ice-cap waxed and waned.more » These environmental changes intersected important evolutionary events, namely, the explosive colonization of the emergent land areas by plants and the rise of terrestrial vertebrates. In this paper the authors present paleogeographic reconstructions for 6 intervals during the Carboniferous. These maps illustrate the latitudinal position of the continents deduced from paleomagnetic data and the distribution of climatically restricted lithofacies (coal, bauxite, evaporite, calcrete, and tillite), the inferred location of active plate boundaries, and the changing configuration of mountains, land, shallow seas, and deep ocean basins. For each of these paleogeographic maps a climatic simulation was run using the Parametric Climate Model. These simulations predict the distribution of high and low pressure cells, prevailing wind directions, pole-to-equator temperature gradient, relative wetness/dryness, as well as zones of coastal upwelling.« less

Electromagnetic study of lithospheric structure in the marginal zone of East European Craton in NW Poland

NASA Astrophysics Data System (ADS)

Jóźwiak, Waldemar

2013-10-01

The marginal zone of the East European Platform, an area of key importance for our understanding of the geotectonic history of Europe, has been a challenge for geophysicists for many years. The basic research method is seismic survey, but many important data on physical properties and structure of the lithosphere may also be provided by the electromagnetic methods. In this paper, results of deep basement study by electromagnetic methods performed in Poland since the mid-1960s are presented. Over this time, several hundred long-period soundings have been executed providing an assessment of the electric conductivity distribution in the crust and upper mantle. Numerous 1D, 2D, and pseudo-3D electric conductivity models were constructed, and a new interpretation method based on Horizontal Magnetic Tensor analysis has been applied recently. The results show that the contact zone is of lithospheric discontinuity character and there are distinct differences in geoelectric structures between the Precambrian Platform, transitional zone (TESZ), and the Paleozoic Platform. The wide-spread conducting complexes in the crust with integral conductivity values reaching 10 000 S at 20-30 km depths are most spectacular. They are most likely consequences of geological processes related to Caledonian and Variscan orogenesis. The upper mantle conductivity is also variable, the thickness of high-resistive lithospheric plates ranging from 120-140 km under the Paleozoic Platform to 220-240 km under the East European Platform.

Tertiary coals in South Texas: Anomalous cannel-like coals of Webb County (Claiborne Group, Eocene) and lignites of Atascosa County (Jackson Group, Eocene) - Geologic setting, character, source-rock and coal-bed methane potential

USGS Publications Warehouse

Warwick, Peter D.; Aubourg, Claire E.; Willett, Jason C.

1999-01-01

The coal-bearing Gulf of Mexico Coastal Plain of North America contains a variety of depositional settings and coal types. The coal-bearing region extends westward from Alabama and Mississippi, across Louisiana to the northern part of the Mississippi Embayment, and then southward to eastern Arkansas, Texas and northern Mexico (fig. 1). Most of the coal currently mined in Texas is lignite from the upper part of the Wilcox Group (Paleocene-Eocene) and, in Louisiana, lignite is mined from the lower part of the Wilcox (fig. 2). Gulf Coast coal is used primarily as fuel for mine-mouth electric plants. On this field trip we will visit the only two non-Wilcox coal mining intervals in the Texas-Louisiana Coastal Plain; these include the San Pedro - Santo Tomas bituminous cannel-like coal zone of the Eocene Claiborne Group, and the San Miguel lignite coal zone of the Eocene Jackson Group (fig. 2). Other coal-mining areas in northern Mexico are currently producing bituminous coal from the Cretaceous Olmos Formation of the Navaro Group (fig. 2).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hower, J.C.; Ferm, J.C.; Cobb, J.C.

This project consists of three specific areas of coal petrology: spectral fluorescence of liptinite macerals; properties of semi-inert macerals; and size/form/microlithotype association of pyrite/marcasite. Techniques developed in the first three areas were used in additional research on Mannington and Dunbar coals in western Kentucky and the Alma coal zone in eastern Kentucky. Some of the findings are: percent variations (pseudovitrinite-vitrinite/vitrinite X100) indicate greater dispersions in Vicker's microhardness values, MH(v), of vitrinite and pseudovitrinite from eastern Kentucky coals than those of western Kentucky coals; reflectance data confirm a previously suspected rank increase from eastern Knott and Magoffin Counties to eastern Pikemore » County; microhardness investigation of Upper Elkhorn 2 coal in eastern Kentucky indicates that pseudovitrinite is consistently harder than vitrinite; and of the western coals studied, Dunbar and Lead Creek, there appears to be some correlations between vitrinite, ash, sulfur, and thickness. 6 tables.« less

Geologic Map of Upper Cretaceous and Tertiary Strata and Coal Stratigraphy of the Paleocene Fort Union Formation, Rawlins-Little Snake River Area, South-Central Wyoming

USGS Publications Warehouse

Hettinger, R.D.; Honey, J.G.; Ellis, M.S.; Barclay, C.S.V.; East, J.A.

2008-01-01

This report provides a map and detailed descriptions of geologic formations for a 1,250 square mile region in the Rawlins-Little Snake River coal field in the eastern part of the Washakie and Great Divide Basins of south-central Wyoming. Mapping of geologic formations and coal beds was conducted at a scale of 1:24,000 and compiled at a scale of 1:100,000. Emphasis was placed on coal-bearing strata of the China Butte and Overland Members of the Paleocene Fort Union Formation. Surface stratigraphic sections were measured and described and well logs were examined to determine the lateral continuity of individual coal beds; the coal-bed stratigraphy is shown on correlation diagrams. A structure contour and overburden map constructed on the uppermost coal bed in the China Butte Member is also provided.

Correlation of coal beds in the Fruitland Formation as interpreted from geophysical logs, east-central San Juan County, New Mexico

USGS Publications Warehouse

Sandberg, Dorothy T.

1986-01-01

Correlation of coal beds in the Fruitland Formation (Upper Cretaceous) in the subsurface, from interpretation of geophysical logs, is an outgrowth of unpublished studies of deep coal on the Navajo Reservation by the author in the Toadlena 30 x 60 minute quadrangle, New Mexico, and by W. J. Mapel in the Farmington 30 x 60 minute quadrangle, New Mexico.  The lines of sections of this report extend eastward from the reservation into east-central San Juan County, which is in the western part of the San Juan Basin.  In this area, the rocks dip gently northeast toward the central part of the basin.  The thick coal is less than 1,500 feet beneath the surface.  Of the 53 logs in the sections, 48 are from oil- and gas-test holes, and 5 are from coal-test holes (see table 1).  Stratigraphic relations of the Upper Cretaceous Lewis Shale, Pictured Cliffs Sandstone, and Fruitland Formation, shown on the cross sections and briefly reviewed below, have been previously described for this or other parts of the San Juan Basin by Hayes and Zapp (1955), Beaumont (1971), Fassett and hinds (1971), O;Sullivan and other (1972), and Molenaar (1983), among others.

Provenance of Miocene Hinterland Basins in Ecuador: Implications for the Growth of Topographic Barriers in the Northern Andes

NASA Astrophysics Data System (ADS)

George, S. W. M.; Horton, B. K.; Vallejo, C.; Nogales, V.

2017-12-01

Establishment of the Eastern Cordillera of Ecuador as an Andean topographic barrier caused significant drainage reorganization, perhaps even as dramatic as the reversal of the Amazon River. Cenozoic growth of this barrier coincided with substantial increases in speciation rates in Andean and Amazonian environments. Situated in the Interandean Depression between the Eastern Cordillera and Western Cordillera of Ecuador, a series of well-preserved Miocene intermontane basins offer a unique opportunity to constrain the along-strike development of the flanking north-trending cordilleras as drainage divides in the Northern Andes. Here were provide detrital zircon U-Pb geochronological results for 17 samples from Ecuadorian hinterland basins (Cuenca, Giron-Santa Isabel, Nabón, Loja, and Vilcabamba), supplemented with measured sections in the Cuenca Basin, to provide insights on orogenic development of the cordilleras of Ecuador during the Miocene. In addition, we characterize the age distributions of basement units to more precisely determine sediment routing patterns through time. Detrital zircon geochronological data yields regional upsection trends throughout Miocene stratigraphic sections marked by: (1) middle Miocene deposits containing a strong syndepositional age peak, with a complementary Eocene-Oligocene peak in varying abundances, and subsidiary low-intensity Paleozoic-Proterozoic age peaks; and (2a) upper Miocene deposits maintaining similar trends to that of the middle Miocene, or (2b) upper Miocene deposits showing a dramatic shutoff of most Cenozoic populations and a switch to Paleozoic-Proterozoic sources, as seen in the Nabón and Loja basins. Syndepositional signatures reflect derivation from the magmatic arc, while varying inputs of Eocene-Oligocene zircons were derived from the Eocene-Oligocene volcanic rocks that comprise the effective basement of much of the Interandean Depression. The late Miocene shift to Paleozoic-Proterozoic sources observed in the Nabón and Loja basins reflects rapid exhumation of crystalline sources, and an eastward shift of the drainage divide, associated with exhumation of the Eastern Cordillera, which is supported by rapid cooling observed in thermochronological datasets and a switch to alluvial fan facies in the hinterland basins.

Diagenetic mineralization in Pennsylvanian coals from Indiana, USA: 13C/12C and 18O/16O implications for cleat origin and coalbed methane generation

USGS Publications Warehouse

Solano-Acosta, W.; Schimmelmann, A.; Mastalerz, Maria; Arango, I.

2008-01-01

Cleats and fractures in southwestern Indiana coal seams are often filled with authigenic kaolinite and/or calcite. Carbon- and oxygen-stable isotope ratios of kaolinite, calcite, and coalbed CO2 were evaluated in combination with measured values and published estimates of ??18O of coalbed paleowaters that had been present at the time of mineralization. ??18Omineral and ??18Owater values jointly constrain the paleotemperature of mineralization. The isotopic evidence and the thermal and tectonic history of this part of the Illinois Basin led to the conclusion that maximum burial and heat-sterilization of coal seams approximately 272??Ma ago was followed by advective heat redistribution and concurrent precipitation of kaolinite in cleats at a burial depth of < 1600??m at ??? 78 ?? 5????C. Post-Paleozoic uplift, the development of a second generation of cleats, and subsequent precipitation of calcite occurred at shallower burial depth between ??? 500 to ??? 1300??m at a lower temperature of 43 ?? 6????C. The available paleowater in coalbeds was likely ocean water and/or tropical meteoric water with a ??18Owater ??? - 1.25??? versus VSMOW. Inoculation of coalbeds with methanogenic CO2-reducing microbes occurred at an even later time, because modern microbially influenced 13C-enriched coalbed CO2 (i.e., the isotopically fractionated residue of microbial CO2 reduction) is out of isotopic equilibrium with 13C-depleted calcite in cleats. ?? 2007 Elsevier B.V. All rights reserved.

Crustal structure in the Elko-Carlin Region, Nevada, during Eocene gold mineralization: Ruby-East Humboldt metamorphic core complex as a guide to the deep crust

USGS Publications Warehouse

Howard, K.A.

2003-01-01

The deep crustal rocks exposed in the Ruby-East Humboldt metamorphic core complex, northeastern Nevada, provide a guide for reconstructing Eocene crustal structure ~50 km to the west near the Carlin trend of gold deposits. The deep crustal rocks, in the footwall of a west-dipping normal-sense shear system, may have underlain the Pinon and Adobe Ranges about 50 km to the west before Tertiary extension, close to or under part of the Carlin trend. Eocene lakes formed on the hanging wall of the fault system during an early phase of extension and may have been linked to a fluid reservoir for hydrothermal circulation. The magnitude and timing of Paleogene extension remain indistinct, but dikes and tilt axes in the upper crust indicate that spreading was east-west to northwest-southeast, perpendicular to a Paleozoic and Mesozoic orogen that the spreading overprinted. High geothermal gradients associated with Eocene or older crustal thinning may have contributed to hydrothermal circulation in the upper crust. Late Eocene eruptions, upper crustal dike intrusion, and gold mineralization approximately coincided temporally with deep intrusion of Eocene sills of granite and quartz diorite and shallower intrusion of the Harrison Pass pluton into the core-complex rocks. Stacked Mesozoic nappes of metamorphosed Paleozoic and Precambrian rocks in the core complex lay at least 13 to 20 km deep in Eocene time, on the basis of geobarometry studies. In the northern part of the complex, the presently exposed rocks had been even deeper in the late Mesozoic, to >30 km depths, before losing part of their cover by Eocene time. Nappes in the core plunge northward beneath the originally thicker Mesozoic tectonic cover in the north part of the core complex. Mesozoic nappes and tectonic wedging likely occupied the thickened midlevel crustal section between the deep crustal core-complex intrusions and nappes and the overlying upper crust. These structures, as well as the subsequent large-displacement Cenozoic extensional faulting and flow in the deep crust, would be expected to blur the expression of any regional structural roots that could correlate with mineral belts. Structural mismatch of the mineralized upper crust and the tectonically complex middle crust suggests that the Carlin trend relates not to subjacent deeply penetrating rooted structures but to favorable upper crustal host rocks aligned within a relatively coherent regional block of upper crust.

Long term changes in the concentration of radium in discharge waters of coal mines and Upper Silesian rivers.

PubMed

Chałupnik, Stanisław; Wysocka, Małgorzata; Janson, Ewa; Chmielewska, Izabela; Wiesner, Marta

2017-05-01

According to the latest guidelines of the International Atomic Energy Agency (IAEA, 2016), coal mining is one of the most important contributors to occupational exposure. Coal mining contributes about 45% of the total annual collective dose obtained by workers due to the exposure at places of working. One of the sources of exposure in mining are formation brines with elevated concentrations of natural radionuclides, the most common are radium 226 Ra and 228 Ra. Radium isotopes often occur in formation waters in underground collieries in the Upper Silesian region (USCB) in Poland. Significant amounts of radium remain underground in the form of radioactive deposits created as a result of spontaneous deposition or water treatment. This phenomenon leads to the increase of radiation hazard for miners. The remaining activities of 226 Ra and 228 Ra are released into the rivers with mine effluents, causing the contamination of bottom sediments and river banks. The results of radioactivity monitoring of effluents and river waters are presented here to illustrate a trend of long-term changes in environmental contamination, caused by mining industry in the Upper Silesian Region. Copyright © 2017 Elsevier Ltd. All rights reserved.

Late Pennsylvanian climate changes and palynomorph extinctions

USGS Publications Warehouse

Kosanke, R.M.; Cecil, C.B.

1996-01-01

A major floral change occurs in the Upper Pennsylvanian strata in the Midcontinent, Illinois basin, and in the northern Appalachian basin of eastern United States. Lycospora spp. (derived from arborescent lycopsids) became extinct along with some other palynomorph taxa. This investigation is concerned with the importance of this major floral change. Samples were studied from western Pennsylvania, eastern Ohio, and West Virginia (from a previous study) cover the stratigraphic interval from the Upper Freeport coal bed, uppermost part of the Allegheny Formation, to the Mahoning, Mason, Brush Creek, Wilgus, and Anderson coal beds in the lower part of the Conemaugh Formation. The floral change occurs either at or below the accepted Desmoinesian-Missourian boundary in the Midcontinent and Illinois basin, whereas in the northern Appalachians this change occurs in the lower part of the Conemaugh Formation, between the Mahoning and Brush Creek coal beds, or when the Mason is present, between the Mahoning and Mason coal beds. With the advent of late Middle Pennsylvanian time, the climate began to change from wet tropical to seasonal tropical. The Middle-Upper Pennsylvanian boundary is the culmination of this drying trend, which was marked by reduction of available water. The peat swamps are interpreted as having changed from the domed type of bog to the planar type under these circumstances. Thus, in general, the coals of the Conemaugh Formation are characteristically much thinner than those of the Allegheny Formation. This was caused by a number of factors including reduced or more seasonal rainfall, decline of arborescent lycopsids, and the increased dominance of herbaceous and fern plants. As a result, there are fewer minable coal beds in the Conemaugh Formation. The first coal bed above the extinction of Lycospora spp. is dominated by the palynomorph taxon Endosporites globiformis which is derived from a heterosporous, herbaceous lycopsid. However, Sigillaria, another arborescent lycopsid, did not become extinct at this time as evidenced by the presence of the palynomorph genus Crassispora which is derived from Sigillaria. The reason for the survival of Sigillaria is not known, but it may have been able to adapt, in a limited fashion, to some sort of specialized microenvironment. The ferns, based on palynomorph occurrence, become numerically more important throughout the balance of the Conemaugh Formation, and dominate the Pittsburgh No. 8 and Pomeroy coal beds in the overlying Monogahela Formation.

Origin of a classic cratonic sheet sandstone: Stratigraphy across the Sauk II-Sauk III boundary in the Upper Mississippi Valley

USGS Publications Warehouse

Runkel, Anthony C.; McKay, R.M.; Palmer, A.R.

1998-01-01

The origin of cratonic sheet sandstones of Proterozoic and early Paleozoic age has been a long-standing problem for sedimentologists. Lower Paleozoic strata in the Upper Mississippi Valley are best known for several such sandstone bodies, the regional depositional histories of which are poorly understood. We have combined outcrop and subsurface data from six states to place the Upper Cambrian Wonewoc (Ironton and Galesville) Sandstone in a well-constrained stratigraphic framework across thousands of square kilometers. This framework makes it possible for the first time to construct a regional-scale depositional model that explains the origin of this and other cratonic sheet sandstones. The Wonewoc Sandstone, although mapped as a single contiguous sheet, is a stratigraphically complex unit that was deposited during three distinct conditions of relative sea level that span parts of four trilobite zones. During a relative highstand of sea level in Crepicephalus Zone time, quartzose sandstone lithofacies aggraded more or less vertically in nearshore-marine and terrestrial environments across much of the present-day out-crop belt around the Wisconsin arch. At the same time, finer grained, feldspathic sandstone, siltstone, and shale aggraded in deeper water immediately seaward of the quartzose sand, and shale and carbonate sediment accumulated in the most distal areas. During Aphelaspis and Dunderbergia Zones time a relative fall in sea level led to the dispersal of quartzose sand into a basinward-tapering, sheet-like body across much of the Upper Mississippi Valley. During early Elvinia Zone time a major transgression led to deposition of a second sheet sandstone that is generally similar to the underlying regressive sheet. The results of this investigation also demonstrate how subtle sequence-bounding unconformities may be recognized in mature, cratonic siliciclastics. We place the Sauk II-Sauk III subsequence boundary at the base of the coarsest bed in the Wonewoc Sandstone, a lag developed through erosion that occurred during the regional regressive-transgressive event that spanned Aphelaspis to early Elvinia Zones time. Such sequence-bounding unconformities are difficult to recognize where they are contained within coarse siliciclastics of the Upper Mississippi Valley, because they separate strata that are texturally and mineralogically similar, and because erosion occurred on a loose, sandy substrate along a low, uniform gradient, and in a nonvegetated terrestrial environment. Furthermore, the ultramature mineral composition of the exposed substrate is resistant to the development of a recognizable weathering profile. The well-known sheet geometry of the Wonewoc and other units of lower Paleozoic sandstone of this area is not dependent on atypical terrestrial depositional conditions conducive to the widespread distribution of sand, as commonly believed. Sand was spread into a sheet dominantly within the marine realm in a manner similar to that inferred for many better-known sandstone bodies deposited in the North American Cretaceous Western Interior seaway and Tertiary Gulf of Mexico. The laterally extensive, thin character of the Upper Mississippi Valley sandstone bodies compared to these other sandstone bodies simply reflects deposition of a continuously abundant supply of sand on a relatively stable, nearly flat basin of slow, uniform subsidence during changes in sea level. The dearth of shale in this and other cratonic sandstones can be indirectly attributed to the same controls, which led to an uncommonly low preservation potential for fairweather deposits on the shoreface.

Preliminary interpretations of hydrogeologic data from boreholes and springs in the vicinity of Davis and Lavender Canyons, Utah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thackston, J.W.

1987-09-01

This information is presented in tabular form and includes station locations, potentiometric levels, permeabilities, transmissibilities, total dissolved solids, depths, locations, data sources, a fracture log of the Gibson Dome No. 1 (GD-1) borehole, and other useful information. Three different ranking scales were used to evaluate available drill-stem test (DST) data. A preliminary detailed hydrogeologic column was prepared using the DST data and GD-1 borehole information. A series of preliminary potentiometric maps was interpreted from these data for the different hydrogeologic units. Preliminary potentiometric surface maps for the Lower Paleozoic Aquifer, Pennsylvanian Aquitard, Permian Aquifer/Aquitard, and Mesozoic (Jurassic) Aquifer were constructed.more » These maps show a general southwest flow direction in the Lower Paleozoic Aquifer, extremely low permeabilities in the Pennsylvanian, northerly ground-water flow in the Permian, and westward flow direction in the Mesozoic unit. The few data points in the Pennsylvanian tend to indicate that ground water in the upper Paradox Formation may be flowing toward the west and southwest in the area southeast of Six-Shooter Peaks.« less

Petroleum geology of Azov-Black Sea region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lukin, A.; Trofimenko, G.

1995-08-01

The main features of tectonics, stratigraphy, paleogeography, lithology, hydrogeology, geothermics and hydrocarbon-bearingness of Azov-Black Sea Region are characterized on the basis of present-day data. Among the most prospective petroliferous complexes one ought to mention: Paleozoic (S - D - C{sub 1}) of Near-Dobrudga foredeep, Triassic - Jurassic of the Black Sea (shelf and continental slope); Lower Cretaceous of the various parts of the Region; Upper Cretaceous of the Black Sea shelf; Paleocene-Eocene of Azov Sea. In addition certain prospects are connected with Precambrian and Paleozoic basements within conjunction zone between Eastern-Europe platform and Scythian plate. Geodynamic evolution of the Regionmore » is considered with determination of tension and compression stages and characteristic of the main regularities of diapirs, mud volcanos, swells, horsts and grabens distribution. There determined the most interesting types of hydrocarbon traps connected with various tectonic forms, river and deltaic channels, bars, conturites, carbonate reefs, etc. Paleogeothermic and paleogeodynamic reconstructions allow to determine the main phases of oil and gas accumulation. The most prospective oil-gas-bearing zones and areas are mapped.« less

Summary of the geology and resources of uranium in the San Juan Basin and adjacent region, New Mexico, Arizona, Utah, and Colorado

USGS Publications Warehouse

Ridgley, Jennie L.; Green, M.W.; Pierson, C.T.; Finch, W.I.; Lupe, R.D.

1978-01-01

The San Juan Basin and adjacent region lie predominantly in the southeastern part of the uranium-rich Colorado Plateau of New Mexico, Arizona, Utah, and Colorado. Underlying the province are rocks of the Precambrian basement complex composed mainly of igneous and metamorphic rocks; a thickness of about 3,600 meters of generally horizontal Paleozoic, Mesozoic, and Cenozoic sedimentary rocks; and a variety of Upper Cretaceous and Cenozoic igneous rocks. Sedimentary rocks of the sequence are commonly eroded and well exposed near the present basin margins where Tertiary tectonic activity has uplifted, folded, and faulted the sequence into its present geologic configuration of basins, platforms, monoclines, and other related structural features. Sedimentary rocks of Jurassic age in the southern part of the San Juan Basin contain the largest uranium deposits in the United States, and offer the promise of additional uranium deposits. Elsewhere in the basin and the adjacent Colorado Plateau, reserves and resources of uranium are known primarily in Triassic, Jurassic, and Cretaceous strata. Only scattered occurrences of uranium are known in Paleozoic

Paleozoic sedimentary rocks in the Red Dog Zn-Pb-Ag district and vicinity, western Brooks Range, Alaska: provenance, deposition, and metallogenic significance

USGS Publications Warehouse

Slack, John F.; Dumoulin, Julie A.; Schmidt, J.M.; Young, L.E.; Rombach, Cameron

2004-01-01

The distribution and composition of Paleozoic strata in the western Brooks Range may have played a fundamental role in Zn-Pb mineralization of the Red Dog district. In our model, deposition and early lithification of biogenic chert and bedded siliceous rocks in the upper part of the Kuna Formation served as a regional hydrologic seal, acting as a cap rock to heat and hydrothermal fluids during Late Mississippian base-metal mineralization. Equally important was the iron-poor composition of black shales of the Kuna Formation (i.e., low Fe/Ti ratios), which limited synsedimentary pyrite formation in precursor sediments, resulting in significant H2S production in pore waters through the interaction of aqueous sulfate with abundant organic matter. This H2S may have been critical to the subsurface deposition of the huge quantities of Zn and Pb in the district. On the basis of this model, we propose that low Fe/Ti and S/C ratios in black shale sequences are potential basin-scale exploration guides for giant sediment-hosted, stratiform Zn-Pb-Ag deposits.

Ellsworth mountains: Position in West Antarctica due to sea-floor spreading

USGS Publications Warehouse

Schopf, J.M.

1969-01-01

Similarities of middle and upper Paleozoic deposits of the Ellsworth Mountains with those of the Pensacola, Horlick, and other Transantarctic mountains indicate that all these ranges may have had a related geologic history. A tentative explanation is now suggested which involves sea-floor spreading and translocation of the Ellsworth crustal block from its original location adjacent to the East Antarctic Shield. Accordingly, the islands of West Antarctica may differ in origin and the Transantarctic Mountains of East Antarctica may represent one margin of an ancient rift.

Intraplate mountain building in response to continent continent collision—the Ancestral Rocky Mountains (North America) and inferences drawn from the Tien Shan (Central Asia)

NASA Astrophysics Data System (ADS)

Dickerson, Patricia Wood

2003-04-01

The intraplate Ancestral Rocky Mountains of western North America extend from British Columbia, Canada, to Chihuahua, Mexico, and formed during Early Carboniferous through Early Permian time in response to continent-continent collision of Laurentia with Gondwana—the conjoined masses of Africa and South America, including Yucatán and Florida. Uplifts and flanking basins also formed within the Laurentian Midcontinent. On the Gondwanan continent, well inboard from the marginal fold belts, a counterpart structural array developed during the same period. Intraplate deformation began when full collisional plate coupling had been achieved along the continental margin; the intervening ocean had been closed and subduction had ceased—that is, the distinction between upper versus lower plates became moot. Ancestral Rockies deformation was not accompanied by volcanism. Basement shear zones that formed during Mesoproterozoic rifting of Laurentia were reactivated and exerted significant control on the locations, orientations, and modes of displacement on late Paleozoic faults. Ancestral Rocky Mountain uplifts extend as far south as Chihuahua and west Texas (28° to 33°N, 102° to 109°W) and include the Florida-Moyotes, Placer de Guadalupe-Carrizalillo, Ojinaga-Tascotal and Hueco Mountain blocks, as well as the Diablo and Central Basin Platforms. All are cored with Laurentian Proterozoic crystalline basement rocks and host correlative Paleozoic stratigraphic successions. Pre-late Paleozoic deformational, thermal, and metamorphic histories are similar as well. Southern Ancestral Rocky Mountain structures terminate along a line that trends approximately N 40°E (present coordinates), a common orientation for Mesoproterozoic extensional structures throughout southern to central North America. Continuing Tien Shan intraplate deformation (Central Asia) has created an analogous array of uplifts and basins in response to the collision of India with Eurasia, beginning in late Miocene time when full coupling of the colliding plates had occurred. As in the Laurentia-Gondwana case, structures of similar magnitude and spacing to those in Eurasia have developed in the Indian plate. Within the present orogen two ancient suture zones have been reactivated—the early Paleozoic Terskey zone and the late Paleozoic Turkestan suture between the Siberian and East Gondwanan cratons. Inverted Proterozoic to early Paleozoic rift structures and passive-margin deposits are exposed north of the Terskey zone. In the Alay and Tarim complexes, Vendian to mid-Carboniferous passive-margin strata and the subjacent Proterozoic crystalline basement have been uplifted. Data on Tien Shan uplifts, basins, structural arrays, and deformation rates guide paleotectonic interpretations of ancient intraplate mountain belts. Similarly, exhumed deep crustal shear zones in the Ancestral Rockies offer insight into partitioning and reorientation of strain during contemporary intraplate deformation.

1. AIR/MANWAY SHAFT WALL AND FAN HOUSE FOUNDATION WALL FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. AIR/MANWAY SHAFT WALL AND FAN HOUSE FOUNDATION WALL FROM NORTHWEST. AEROVANE FAN AT UPPER LEFT, SCAFFOLD AND LEPLEY VENTILATOR AT UPPER RIGHT. - Consolidation Coal Company Mine No. 11, Air-Manway Shaft, East side of State Route 936, Midlothian, Allegany County, MD

An Intracratonic Record of North American Tectonics

NASA Astrophysics Data System (ADS)

Lovell, Thomas Rudolph

Investigating how continents change throughout geologic time provides insight into the underlying plate tectonic process that shapes our world. Researchers aiming to understand plate tectonics typically investigate records exposed at plate margins, as these areas contain direct structural and stratigraphic information relating to tectonic plate interaction. However, these margins are also susceptible to destruction, as orogenic processes tend to punctuate records of plate tectonics. In contrast, intracratonic basins are long-lived depressions located inside cratons, shielded from the destructive forces associated with the plate tectonic process. The ability of cratonic basins to preserve sedimentological records for extended periods of geologic time makes them candidates for recording long term changes in continents driven by tectonics and eustacy. This research utilizes an intracratonic basin to better understand how the North American continent has changed throughout Phanerozoic time. This research resolves geochronologic, thermochronologic, and sedimentologic changes throughout Phanerozoic time (>500 Ma) within the intracratonic Illinois Basin detrital record. Core and outcrop sampling provide the bulk of material upon which detrital zircon geochronologic, detrital apatite thermochronologic, and thin section petrographic analyses were performed. Geochronologic evidence presented in Chapters 2 and 3 reveal the Precambrian - Cretaceous strata of the intracratonic Illinois Basin yield three detrital zircon U-Pb age assemblages. Lower Paleozoic strata yield ages corresponding to predominantly cratonic sources (Archean - Mesoproterozoic). In contrast, Middle - Upper Paleozoic strata have a dominant Appalachian orogen (Neoproterozoic - Paleozoic) signal. Cretaceous strata yield similar ages to underlying Upper Paleozoic strata. We conclude that changes in the provenance of Illinois Basin strata result from eustatic events and tectonic forcings. This evidence demonstrates that changes in the detrital record of the Illinois Basin coincide with well-documented, major tectonic and eustatic events that altered and shaped North American plate margins. Chapter 4 presents 24 apatite (U-Th)/He (AHe) ages (3 - 423 Ma) taken from subsurface Cambrian and Pennsylvanian sandstones in the Illinois Basin. Time-temperature simulations used to reproduce these ages predict a basin thermal history with a maximum temperature of 170°C in post-Pennsylvanian time followed by Mesozoic cooling at 0.3°C/Myr. These thermal simulations suggest 3 km of additional post-Pennsylvanian burial (assuming 30°C/km geotherm) followed by subsequent Mesozoic - Cenozoic removal. This burial-exhumation history is concurrent with Late Mesozoic tectoniceustatic fluctuations, including Atlantic and Gulf of Mexico opening, rejuvenation of the Appalachian region, and Gulf of Mexico sediment influx, and the Cretaceous high sea level stand. The Geochronologic and thermochronologic evidence presented in the following chapters suggests the Illinois Basin potentially contains a more robust record of North American tectonics than previously thought. These observations provide a new perspective on the utility of intracratonic basins in understanding long term changes to continental bodies.

Study of Nox Emission Characteristics of a 1025t/h Coal-Fired Circulating Fluidized Bed Boiler

NASA Astrophysics Data System (ADS)

Li, Q. Y.; Mi, Z. D.; Zhang, Q. F.

Measurements of emission are carried out in a 1025t/h CFB boiler. The effect of some factors including coal properties, bed temperature, unit load, excess air on the emission of NOx are investigated. The measurement results show that the N concentration in the coal is dominant parameter to predict the NOx emission from a large-scale CFB boiler. NOx emission from the 1025t/h CFB boiler increases with cyclone temperature and upper pressure drop due to post combustion and external cycle.

Criteria to aid in the establishment of genetic boundaries within a carboniferous basin: Mary Lee Coal Zone, Black Warrior Basin, Alabama

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryant, T.W.; Gastaldo, R.A.

The upper part of the Mary Lee coal zone of the Lower Pennsylvanian (Westphalian A) Pottsville Formation in northwestern Alabama is composed of the Mary Lee and the Newcastle coal seams. The Mary Lee coal seam has been economically significant in terms of both mining and coal-bed methane production. A sedimentological, paleontological, and geochemical investigation of the lithologies associated with this coal zone was done to define the changes that occur in facies changing from terrestrial into marine facies. A ravinement bed, ranging in thickness from 13.0 deposits. Fifteen surficially exposed sections were observed and sampled in the study area.more » Geochemical analyses were done on samples collected from seven sections along the perimeter of the study area. The analyses conducted involved inductively coupled atomic plasma spectrometry (ICAP) for seven elemental oxides that include aluminum, iron, silica, calcium, potassium, magnesium and manganese. Atomic absorption was used to determine sodium content. Carbonate carbon was determined by weight percent difference after hydrochloric acid treatment, whereas organic carbon content was determined by use of a carbon analyzer on a LECO[sup TM] induction furnace. Sulfur content was also determined by a LECO induction furnace equipped with a sulfur analyzer. Loss-on-ignition (LOI) percentage was based upon change in weight of samples after a period of 30 min in a muffle furnace at a temperature of 1000[degrees]C. The combination of sedimentological, paleontological, and geochemical characteristics were used to better understand the depositional setting of the upper Mary Lee coal zone in terms of a transgressive event. These criteria can be used in similar basin systems to better understand the depositional history of those settings.« less

Microstructure and significance of cordaitean reproductive organs from the lower Permian of Gansu, Northwest China

NASA Astrophysics Data System (ADS)

Wang, Zixi; Sun, Bainian; Sun, Fankai; Xiong, Conghui; Chen, Yingquan; Wang, Xuelian

2018-06-01

The Late Paleozoic strata are well exposed in Yongchang County, Gansu Province, Northwest China. The strata contain numerous plant fossils. Hence, Yongchang County is a good location to study Paleozoic plants and plate movement. Using well-preserved cordaitean cones and seeds from the lower Permian Taiyuan Formation of Yongchang County, two new species of fossil plants are described, one attributed to the new organ genus Hexianthus (H. shenii sp. nov.) and the other to the seed genus Samaropsis (S. shenii sp. nov.). The micro- and macro-scale features of the cones, including the epidermal features of the bracts and scales, are analyzed in the laboratory. Numerous cordaitean cones with helically arranged bracts and scales (H. shenii sp. nov.) present in the Taiyuan Formation of Yongchang County share similar characteristics with the cordaitean cones which are endemic to the Cathaysian flora. This suggests that the study region was characterized by the Cathaysian flora in the Cisuralian, similar to the Hexi Corridor to the south of the study region. Based on the study of fossil cuticles and their associated plants, the study region of Yongchang County probably had a warm and humid climate during the Cisuralian. In addition, according to the associations between different fossil plants from several localities in Gansu Province (from the Cathaysian flora in the lower Permian to the Cathaysian-Angaran mixed flora in the upper Permian), a possible boundary between the Cathaysian and Angaran floras in Gansu Province can be placed along the Hexi Corridor, which provides important information for the study of floral associations in Northwest China during the Late Paleozoic.

Land disturbances from strip-mining in eastern Kentucky: 1. Upper Cumberland coal reserve district

Treesearch

William T. Plass

1966-01-01

Open-pit or strip-mining - primarily for coal - has expanded rapidly in eastern Kentucky during the past 15 years. Information about the amount, location, and general characteristics of the disturbed areas is necessary for appraising the economic impacts and overall effects of strip-mining in that section of the state, for planning reclamation programs, and for...

An evaluation of processing InSAR Sentinel-1A/B data for correlation of mining subsidence with mining induced tremors in the Upper Silesian Coal Basin (Poland)

NASA Astrophysics Data System (ADS)

Krawczyk, Artur; Grzybek, Radosław

2018-01-01

The Satellite Radar Interferometry is one of the common methods that allow to measure the land subsidence caused by the underground black coal excavation. The interferometry images processed from the repeat-pass Synthetic Aperture Radar (SAR) systems give the spatial image of the terrain subjected to the surface subsidence over mining areas. Until now, the InSAR methods using data from the SAR Systems like ERS-1/ERS-2 and Envisat-1 were limited to a repeat-pass cycle of 35-day only. Recently, the ESA launched Sentinel-1A and 1B, and together they can provide the InSAR coverage in a 6-day repeat cycle. The studied area was the Upper Silesian Coal Basin in Poland, where the underground coal mining causes continuous subsidence of terrain surface and mining tremors (mine-induced seismicity). The main problem was with overlapping the subsidence caused by the mining exploitation with the epicentre tremors. Based on the Sentinel SAR images, research was done in regard to the correlation between the short term ground subsidence range border and the mine-induced seismicity epicentres localisation.

Insights into chemical weathering of the upper continental crust from the geochemistry of ancient glacial diamictites

NASA Astrophysics Data System (ADS)

Li, Su; Gaschnig, Richard M.; Rudnick, Roberta L.

2016-03-01

Glacial diamictites, with ages ranging from ∼2900 to 0.01 Ma, record the changing composition of the upper continental crust through time (Gaschnig et al., 2014). Li concentrations and isotopic compositions, combined with Pb isotopic compositions, chemical index of alteration (CIA) values and relative Sr concentrations are used here to assess the degree of chemical weathering recorded in these deposits and the origin of this signature. The δ7Li values of most of the diamictites (ranging from -3.9 to +3.5) are lower than those of mantle-derived basalts (+3.7 ± 2, 2σ), and the low δ7Li values are generally accompanied by high CIA and low Sr/Sr∗ values (or Sr depletion factor, Sr/Sr∗ = Sr/(Ce∗Nd)0.5), reflecting a weathering signature that may have derived from pre-depositional, syn-depositional, and/or post-depositional weathering processes. Profiles through three glacial diamictites with relatively high CIA (a fresh road cut of the Neoproterozoic Nantuo Formation (CIA = 62-69), and drill cores through the Paleoproterozoic Timeball Hill (CIA = 66-75) and Duitschland Formations (CIA = 84-91)) do not show evidence of significant post-depositional weathering. High Th/U, reflecting loss of uranium during oxidative weathering, is seen in all Paleozoic and Neoproterozoic diamictites and a few Paleoproterozoic deposits. Pb isotopic systematics suggest that this signature was largely inherited from preexisting crust, although a subset of samples (the Neoproterozoic Konnarock, Paleozoic Dwyka, and several of the Paleoproterozoic Duitschland samples) appears to have experienced post-depositional U loss. Modern glaciomarine sediments record little weathering (CIA = 47, Sr/Sr∗ = 0.7, δ7Li = +1.8), consistent with the cold temperatures accompanying glacial periods, and suggesting that limited syn-depositional weathering has occurred. Thus, the chemical weathering signature observed in ancient glacial diamictites appears to be largely inherited from the upper continental crust (UCC) over which the glaciers traversed. The strength of this weathering signature, based on the CIA, is greatest in the Mesoarchean and some of the Paleoproterozoic diamictites and is weaker in the Neoproterozoic and Phanerozoic glacial diamictites. Combining these data with data for Archean shales and other types of post-Paleoproterozoic sedimentary rocks (i.e., shales, mudstones, etc.), it appears that post-Paleoproterozoic upper continental crust experienced less intense chemical weathering, on average, than Archean and Paleoproterozoic upper continental crust.

Micro-PIXE characterisation of uranium occurrence in the coal zones and the mudstones of the Springbok Flats Basin, South Africa

NASA Astrophysics Data System (ADS)

Nxumalo, V.; Kramers, J.; Mongwaketsi, N.; Przybyłowicz, W. J.

2017-08-01

Uranium occurrence and characterisation in the coal samples of the upper coal zones of the Vryheid Formation and mudstones of the Volksrust Formation was investigated using micro-PIXE (Proton-Induced X-ray Emission) and proton backscattering spectrometry (BS) in conjunction with the nuclear microprobe. Two styles of uranium mineralisation in the Springbok Flats Basin were found: syngenetic mineralisation in which uranium occurs organically bound with coal matrix, with no discrete uranium minerals formed, and epigenetic mineralisation in which uranium occurs in veins that are filled with coffinite with botryoidal texture in the mudstones of the Volksrust Formation, overlying the coal zones. Micro-PIXE analysis made it possible to map out trace elements (including uranium) associated with the coals at low levels of detection, which other techniques such as SEM-EDS and ore microscopy failed. This information will help in better understanding of the best extraction methods to be employed to recover uranium from the coals of the Springbok Flats Basin.

Mercury content and petrographic composition in Pennsylvanian coal beds of Indiana, USA

USGS Publications Warehouse

Mastalerz, Maria; Drobniak, A.; Filippelli, G.

2006-01-01

A suite of high volatile bituminous coals of Pennsylvanian age from Indiana has been studied for their mercury (Hg) concentration and relationship between mercury content and maceral and lithotype composition. The coals ranged in Hg content from 0.02 in the Danville Coal Member to 0.31 ppm in the Upper Block Coal Member. Our study indicates that relationships between petrographic composition of coal and mercury content are site specific. This lack of a consistent relationship is explained by the fact that most Hg occurs in pyrite and not in the organic matter itself. Comparison of Hg content in durain/vitrain pairs shows that durain has more frequently a higher Hg content than vitrain, but the difference in frequency is inconsequential and shows no consistent pattern for a single coal bed or a single location. We suggest that increased concentration of Hg in vitrain is related to the presence of epigenetic pyrite in cleats. ?? 2006 Elsevier B.V. All rights reserved.

Depositional environments of the Jurassic Maghara main coal seam in north central Sinai, Egypt

NASA Astrophysics Data System (ADS)

Edress, Nader Ahmed Ahmed; Opluštil, Stanislav; Sýkorová, Ivana

2018-04-01

Twenty-eight channel samples with a cumulative thickness of about 4 m collected from three sections of the Maghara main coal seam in the middle Jurassic Safa Formation have been studied for their lithotype and maceral compositions to reconstruct the character of peat swamp, its hydrological regime and the predominating type of vegetation. Lithotype composition is a combination of dully lithotypes with duroclarain (19% of total cumulative thickness), clarodurain (15%), black durain (15%), and shaly coal (15%) and bright lithotypes represented by clarain (23%), vitrain (12%) and a small proportion of wild fire-generated fusain (1%). Maceral analyses revealed the dominance of vitrinite (70.6% on average), followed by liptinite (25.2%) and inertinite (8.1%). Mineral matter content is ∼9% on average and consists of clay, quartz and pyrite concentrate mostly at the base and the roof of the seam. Dominantly vitrinite composition of coal and extremely low fire- and oxidation-borne inertinite content, together with high Gelification Indices imply predomination of waterlogged anoxic conditions in the precursing mire with water tables mostly above the peat surface throughout most of the time during peat swamp formation. Increases in collotelinite contents and Tissue Preservation Index up the section, followed by a reversal trend in upper third of the coal section, further accompanied by a reversal trend in collodetrinite, liptodetrinite, alginite, sporinite and clay contents records a transition from dominately limnotelmatic and limnic at the lower part to dominately limnotelmatic with increase telmatic condition achieved in the middle part of coal. At the upper part of coal seam an opposite trend marks the return to limnic and limnotelmatic conditions in the final phases of peat swamp history and its subsequent inundation. The proportion of arborescent (mostly coniferous) and herbaceous vegetation varied throughout the section of the coal with tendency of increasing density of arborescent vegetation to the middle part of the coal seam section. The intercalation of coal in shallow marine strata implies that peat swamp precursor formed in a coastal setting, probably on delta plain or lagoon. Its formation was controlled by water table changes driven by sea level fluctuations that created an accommodation space necessary for preservation of peat.

Production history matching to determine reservoir properties of important coal groups in the Upper Pottsville formation, Brookwood and Oak Grove fields, Black Warrior Basin, Alabama

PubMed Central

Karacan, C. Özgen

2015-01-01

The Black Warrior Basin of Alabama is one of the most important coal mining and coalbed methane production areas in the United States. Methane control efforts through degasification that started almost 25 years ago for the sole purpose of ensuring mining safety resulted in more than 5000 coalbed methane wells distributed within various fields throughout the basin. The wells are completed mostly in the Pratt, Mary Lee, and Black Creek coal groups of the Upper Pottsville formation and present a unique opportunity to understand methane reservoir properties of these coals and to improve their degasification performances. The Brookwood and Oak Grove fields in the Black Warrior Basin are probably two of the most important fields in the basin due to current longwall coal mining activities. In this work, methane and water productions of 92 vertical wellbores drilled, some completed 20 years ago, over a current large coal mine district located in these two fields, were analyzed by history matching techniques. The boreholes were completed at the Mary Lee coal group, or at combinations of the Pratt, Mary Lee, and Black Creek groups. History matching models were prepared and performed according to properties of each coal group. Decline curve analyses showed that effective exponential decline rates of the wells were between 2% and 25% per year. Results of production history matching showed, although they varied by coal group, that pressure decreased as much as 80% to nearly 25 psi in some areas and resulted in corresponding decreases in methane content. Water saturation in coals decreased from 100% to between 20 and 80%, improving gas relative permeabilities to as much as 0.8. As a result of primary depletion, permeability of coal seams increased between 10 and 40% compared to their original permeability, which varied between 1 and 10 md depending on depth and coal seam. These results not only can be used for diagnostic and interpretation purposes, but can be used as parameter distributions in probabilistic simulations, as illustrated in the last section of this paper. They can also be used in conjunction with spatial modeling and geological considerations to calculate potential methane emissions in operating mines. PMID:26191096

Closure Time of the Junggar-Balkhash Ocean: Constraints From Late Paleozoic Volcano-Sedimentary Sequences in the Barleik Mountains, West Junggar, NW China

NASA Astrophysics Data System (ADS)

Liu, Bo; Han, Bao-Fu; Chen, Jia-Fu; Ren, Rong; Zheng, Bo; Wang, Zeng-Zhen; Feng, Li-Xia

2017-12-01

The Junggar-Balkhash Ocean was a major branch of the southern Paleo-Asian Ocean. The timing of its closure is important for understanding the history of the Central Asian Orogenic Belt. New sedimentological and geochronological data from the Late Paleozoic volcano-sedimentary sequences in the Barleik Mountains of West Junggar, NW China, help to constrain the closure time of the Junggar-Balkhash Ocean. Tielieketi Formation (Fm) is dominated by littoral sediments, but its upper glauconite-bearing sandstone is interpreted to deposit rapidly in a shallow-water shelf setting. By contrast, Heishantou Fm consists chiefly of volcanic rocks, conformably overlying or in fault contact with Tielieketi Fm. Molaoba Fm is composed of parallel-stratified fine sandstone and sandy conglomerate with graded bedding, typical of nonmarine, fluvial deposition. This formation unconformably overlies the Tielieketi and Heishantou formations and is conformably covered by Kalagang Fm characterized by a continental bimodal volcanic association. The youngest U-Pb ages of detrital zircons from sandstones and zircon U-Pb ages from volcanic rocks suggest that the Tielieketi, Heishantou, Molaoba, and Kalagang formations were deposited during the Famennian-Tournaisian, Tournaisian-early Bashkirian, Gzhelian, and Asselian-Sakmarian, respectively. The absence of upper Bashkirian to Kasimovian was likely caused by tectonic uplifting of the West Junggar terrane. This is compatible with the occurrence of coeval stitching plutons in the West Junggar and adjacent areas. The Junggar-Balkhash Ocean should be finally closed before the Gzhelian, slightly later or concurrent with that of other ocean domains of the southern Paleo-Asian Ocean.

Palynology of late Middle Pennsylvanian coal beds in the Appalachian Basin

USGS Publications Warehouse

Eble, C.F.

2002-01-01

Fossil spores and pollen have long been recognized as valuable tools for identifying and correlating coal beds. This paper describes the palynology of late Middle Pennsylvanian coal beds in the Appalachian Basin with emphasis on forms that assist both intra- and interbasinal coal bed correlation. Stratigraphically important palynomorphs that originate in late Middle Pennsylvanian strata include Torispora securis, Murospora kosankei, Triquitrites minutus, Cadiospora magna, Mooreisporites inusitatus, and Schopfites dimorphus. Taxa that terminate in the late Middle Pennsylvanian include Radiizonates difformis, Densosporites annulatus, Dictyotriletes bireticulatus, Vestispora magna, and Savitrisporites nux. Species of Lycospora, Cirratriradites, Vestispora, and Thymospora, as well as Granasporites medius, Triquitrites sculptilis, and T. securis and their respective ranges slightly higher, in earliest Late Pennsylvanian age strata. Late Middle Pennsylvanian and earliest Late Pennsylvanian strata in the Appalachian Basin correlate with the Radiizonates difformis (RD), Mooreisporites inusitatus (MI), Schopfites colchesterensis-S. dimorphus (CP), and Lycospora granulata-Granasporites medius (GM) spore assemblage zones of the Eastern Interior, or Illinois Basin. In the Western Interior Basin, these strata correlate with the middle-upper portion of the Torispora securis-Laevigatosporites globosus (SG) and lower half of the Thymospora pseudothiessenii-Schopfites dimorphus (PD) assemblage zones. In western Europe, late Middle Pennsylvanian and earliest Late Pennsylvanian strata correlate with the middle-upper portion of the Torispora securis-T. laevigata (SL) and the middle part of the Thymospora obscura-T. thiessenii (OT) spore assemblage zones. Allegheny Formation coal beds also correlate with the Torispora securis (X) and Thymospora obscura (XI) spore assemblages, which were developed for coal beds in Great Britain. ?? 2002 Elsevier Science B.V. All rights reserved.

Inhalation Exposure to Dioxins and dl-PCBs Depending on the Season in Upper Silesia, Poland: A Pilot Study.

PubMed

Dziubanek, Grzegorz; Marchwińska, Ewa; Hajok, Ilona; Piekut, Agata

2016-06-01

The aim of this study was to investigate the seasonal fluctuation of PCDD/Fs and dl-PCBs levels in the ambient air of Upper Silesia in the aspect of human inhalation exposure as well as the estimation of health risk attributed to this exposure pathway to dioxins and dl-PCBs. In the study air samples were taken in five urban districts of Upper Silesia, Poland, where the houses are heated with coal. The same sampling points in summer and winter were analyzed for dioxins/furans and dl-PCBs. In addition, information was collected on awareness of the residents about the co-incineration of plastic waste and effects of this activity on human health. The results show that the average daily exposure of residents of Upper Silesia to TCDD and DLCs in the heating season was about 6.5.-fold higher than in summer. The risk assessment showed that expected excess of cancer cases per 1,000,000 people ranged from 4.5 to 13.2 in winter and from 0.9 to 2.1 in summer. The practice of mixing waste with coal for houses heating has been confirmed by investigated families, who do not associate it with the possibility of negative health effects. Air pollution can be a significant source of dioxin and dl-PCB for people during the winter season, as a result of co-burning coal and waste containing plastics. The dose of dioxins inhaled through the respiratory pathway in winter can be associated with the higher cancer risk in the population of Upper Silesia. Copyright© by the National Institute of Public Health, Prague 2015.

Aerial radiometric and magnetic reconnaissance survey of the Eagle--Dillingham area, Alaska, Mt. Hayes Quadrangle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1978-06-01

The results of a high-sensitivity aerial gamma-ray spectrometer and magnetometer survey of the Mt. Hayes Quadrangle, Alaska, are presented. Instrumentation and methods are described in Volume 1 of this final report. Statistical and geological analysis of the radiometric data revealed two uranium anomalies worthy of field checking as possible prospects. One is located near Mesozoic granite, which is believed to have the best potential for future economic uranium deposits. Another uranium anomaly is associated with Paleozoic-Precambrian rocks and may be caused by augen gneiss or possibly granitic intrusives. Two weakly uraniferous provinces merit study: one in the northwest, which maymore » be related to the Tertiary-Cretaceous coal-bearing unit, and a second in the northeast, which may be related to Mesozoic granites.« less

Lateral variation in geochemistry, petrology, and palynology in the Elswick coal bed, Pike County, Kentucky

USGS Publications Warehouse

Hower, J.C.; Ruppert, L.F.; Eble, C.F.

2007-01-01

The Middle Pennsylvanian/Langsettian (Westphalian A) Elswick coal bed, correlative to the Upper Banner of Virginia, is a rare example of a mined high-sulfur (> 2%) coal in Eastern Kentucky, a region known for low-sulfur coals. To characterize lateral variation in the geochemistry, petrography, and palynology of the Elswick coal bed, three sites were sampled along a southeast-northwest transect within a single mine. At the southeastern site, the lower 101??cm of the 116-cm thick coal is dull, generally dominated by durain and dull clarain. While all benches at this site fit within the previously-defined "mixed palynoflora - moderate/low vitrinite group," suggesting a stressed environment of deposition, the palynology of the benches of the dull interval show greater diversity than might be expected just from the petrology. Lithology is generally similar between the sites, but each site has some differences in the petrology. Overall, the coal bed shows significant lateral variation in properties at the mine scale, some of which can be attributed to the gain or loss of upper and lower lithologies, either through an actual physical merging or through the change in character of lithotypes. Sulfur content varies between the three sites examined for this study. Site 3, located in the northwestern portion of the study area is characterized by a strikingly high sulfur zone (7.45%) in the middle of the coal bed, a feature missing at the other sites. Pyrite and marcasite, in a mid-seam lithotype at the northwestern site (site 3), show signs of overgrowths, indicating multiple generations of sulfide emplacement. The high-sulfur site 3 lithologies all have massive overgrowths of euhedral and framboidal pyrite, fracture- and cleat-fill pyrite, and sulfide emplacement in fusinite lumens. Sulfur is high throughout the mine area, but variations are evident in the extent of secondary growth of sulfides. ?? 2006 Elsevier B.V. All rights reserved.

Geology of the USSR (Chapter IV).

DTIC Science & Technology

1979-10-05

upper part, contuilrng carbon/ coals , is related to averaqe/mean Carboniferous period. However, similar carbon/ coals were brouq!t hy Jackson’s...V.Lant integument and soil formation in archipelago very unfavorably manifests itself very cold and short summer, and also permanent destruction and...and finally by the maritime Ueposits of Cenomanian tier. Furthermore, in archipplago are known the traces of development supposedly Lower Carboniferous

Geology and fuel resources of the southern part of the San Juan Basin, New Mexico. Part 1, The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church

USGS Publications Warehouse

Sears, Julian D.

1934-01-01

The report describes the geology and coal deposits of the southwestern part of the San Juan Basin, N.Mex. The field lies northeast of the town of Gallup, on the Atchison, Topeka & Santa Fe Railway, and is an irregular tract of about 630 square miles in central and west-central McKinley County; it includes the southeast corner of the Navajo Indian Reservation. Settlement is confined to the white families at a few trading posts and the Indian agency at Crown Point and to scattered Navajo Indians. The land forms, drainage, vegetation, and climate are those typical of the highland in the semiarid Southwest.The investigation disclosed complicated relations of the Mancos shale and the Mesaverde formation, of Upper Cretaceous age, and a marked variation in the stratigraphic boundary between them. At the western edge of the field, as in the adjoining Gallup coal district, the Mancos consists of about 725 feet of marine shale almost wholly of Benton (lower Colorado) age. It is overlain by about 1,800 feet of chiefly estuarine and fluviatile deposits that represent the lower part of the Mesaverde formation. In ascending order the Mesaverde here consists of the Gallup sandstone member (which includes local lenses of valuable coal), the Dilco coal member, the Bartlett barren member, the Gibson coal member, and the Allison barren member. Eastward through the field the outcrops extend obliquely across the trend of old shore lines out into the ancient basin of marine deposition, and some of the beds consequently show a progressive lateral change into rocks of littoral and marine types. The Gallup sandstone member is in part replaced by marine shale of the Mancos. The upper part of the Dilco coal member is replaced by the Dalton sandstone member, and still farther east the bottom of the Dalton and the top of the remaining Dilco are replaced by the Mulatto tongue of the Mancos shale. The Bartlett barren member becomes coal-bearing and thus merges with the Gibson. The Gibson coal member is split by the thick Hosta sandstone member, which toward the east and northeast is in turn split by the Satan tongue of the Mancos shale, of upper Niobrara (upper Colorado) age.In general the structure of the rocks is simple, showing a gentle northward dip into the San Juan Basin. At the west edge of the field the rocks dip steeply west in the north end of the prominent ridges known locally as the Hogback. In the eastern part there is a series of pronounced folds, whose crests and troughs retain the gentle basinward dip but whose limbs are steep monoclines that in places are faulted.The coal is of subbituminous rank and of fairly good grade. The coal beds are very irregular and lenticular. Those in the Gallup and Dilco members are of comparatively little importance, reaching a thickness of 4 to 5 feet in only a few places and, in general, being less than 3 feet thick. The coal beds of the Gibson, especially of its lower part, are more numerous and thicker, measurements of 4 to 6 feet thick being fairly common and one bed showing a thickness of 12 feet for more than a mile. No commercial mining has been undertaken in this field, but a few small mines have been used to supply trading posts and the Indian schools at Crown Point and Tohatchi.

Provenance and detrital zircon geochronologic evolution of lower Brookian foreland basin deposits of the western Brooks Range, Alaska, and implications for early Brookian tectonism

USGS Publications Warehouse

Moore, Thomas; O'Sullivan, Paul B.; Potter, Christopher J.; Donelick, Raymond A.

2015-01-01

The Upper Jurassic and Lower Cretaceous part of the Brookian sequence of northern Alaska consists of syntectonic deposits shed from the north-directed, early Brookian orogenic belt. We employ sandstone petrography, detrital zircon U-Pb age analysis, and zircon fission-track double-dating methods to investigate these deposits in a succession of thin regional thrust sheets in the western Brooks Range and in the adjacent Colville foreland basin to determine sediment provenance, sedimentary dispersal patterns, and to reconstruct the evolution of the Brookian orogen. The oldest and structurally highest deposits are allochthonous Upper Jurassic volcanic arc–derived sandstones that rest on accreted ophiolitic and/or subduction assemblage mafic igneous rocks. These strata contain a nearly unimodal Late Jurassic zircon population and are interpreted to be a fragment of a forearc basin that was emplaced onto the Brooks Range during arc-continent collision. Synorogenic deposits found at structurally lower levels contain decreasing amounts of ophiolite and arc debris, Jurassic zircons, and increasing amounts of continentally derived sedimentary detritus accompanied by broadly distributed late Paleozoic and Triassic (359–200 Ma), early Paleozoic (542–359 Ma), and Paleoproterozoic (2000–1750 Ma) zircon populations. The zircon populations display fission-track evidence of cooling during the Brookian event and evidence of an earlier episode of cooling in the late Paleozoic and Triassic. Surprisingly, there is little evidence for erosion of the continental basement of Arctic Alaska, its Paleozoic sedimentary cover, or its hinterland metamorphic rocks in early foreland basin strata at any structural and/or stratigraphic level in the western Brooks Range. Detritus from exhumation of these sources did not arrive in the foreland basin until the middle or late Albian in the central part of the Colville Basin.These observations indicate that two primary provenance areas provided detritus to the early Brookian foreland basin of the western Brooks Range: (1) local sources in the oceanic Angayucham terrane, which forms the upper plate of the orogen, and (2) a sedimentary source region outside of northern Alaska. Pre-Jurassic zircons and continental grain types suggest the latter detritus was derived from a thick succession of Triassic turbidites in the Russian Far East that were originally shed from source areas in the Uralian-Taimyr orogen and deposited in the South Anyui Ocean, interpreted here as an early Mesozoic remnant basin. Structural thickening and northward emplacement onto the continental margin of Chukotka during the Brookian structural event are proposed to have led to development of a highland source area located in eastern Chukotka, Wrangel Island, and Herald Arch region. The abundance of detritus from this source area in most of the samples argues that the Colville Basin and ancestral foreland basins were supplied by longitudinal sediment dispersal systems that extended eastward along the Brooks Range orogen and were tectonically recycled into the active foredeep as the thrust front propagated toward the foreland. Movement of clastic sedimentary material from eastern Chukotka, Wrangel Island, and Herald Arch into Brookian foreland basins in northern Alaska confirms the interpretations of previous workers that the Brookian deformational belt extends into the Russian Far East and demonstrates that the Arctic Alaska–Chukotka microplate was a unified geologic entity by the Early Cretaceous.

Properties, origin and nomenclature of rodlets of the inertinite maceral group in coals of the central Appalachian basin, U.S.A.

USGS Publications Warehouse

Lyons, P.C.; Finkelman, R.B.; Thompson, C.L.; Brown, F.W.; Hatcher, P.G.

1982-01-01

Resin rodlets, sclerenchyma strands and woody splinters, which are collectively called rodlets, were studied by chemical, optical petrographic, and scanning-electron microscopic (SEM) techniques. A study was made of such rodlets from the bituminous coal beds of the central Appalachian basin (Pennsylvanian; Upper Carboniferous) of the United States. Comparisons were made with rodlets from coal beds of the Illinois basin, the Southern Anthracite Field of Pennsylvania, the St. Rose coal field of Nova Scotia, and European and other coal fields. In order to determine their physical and chemical properties, a detailed study was made of the rodlets from the Pomeroy coal bed (high volatile A bituminous coal; Monongahela Formation; Upper Pennsylvanian) of Kanawha County, West Virginia. The origin of the rodlets was determined by a comparative analysis of a medullosan (seed fern) stem from the Herrin (No. 6) coal bed (high volatile C bituminous coal; Carbondale Formation) from Washington County, Illinois. Rodlets are commonly concentrated in fusain or carbominerite layers or lenses in bituminous coal beds of the central Appalachian basin. Most of the rodlets examined in our study were probably derived from medullosan seed ferns. The three types of rodlets are distinguished on the basis of cellularity, morphology and fracture. The resin rodlets studied by us are noncellular and appear to be similar in properties and origin to those found in coal beds of the Middle and Upper Pennsylvanian of the Illinois basin. The resin rodlets extracted from the Pomeroy coal bed exhibit high relief and high reflectance when polished and viewed in reflected light; they are opaque in transmitted light. In cross section, the resin rodlets are oval to round and have diameters ranging from 60 to 450 ??m. Many are solid, but some have vesicles, canals or cavities, which are commonly filled with clay, probably kaolinite. Typically, they have distinct fracture patterns ("kerfs") in longitudinal and cross sections and many are characterized by dense (probably oxidized) rims. The orientation and amounts of void space and mineralization of resin rodlets in coal have resulted in much confusion in their recognition and classification. The resin rodlets are petrographically recognized as sclerotinites of the inertinite maceral group. We here propose that resin rodlets be assigned to the maceral variety of sclerotinites termed "resino-sclerotinite" because of their presumable resinous origin. Other investigators have confused some fusinitized resin rodlets with fungal masses, which have different morphological properties and which probably have different chemical properties. We here propose that such fungal masses be assigned to the maceral variety of sclerotinites termed "fungo-sclerotinite.". The sclerenchyma strands examined in our study are cellular, thick-walled, and crescent-shaped in cross section. They exhibit high reflectance and high relief and belong to semifusinite and fusinite of the inertinite maceral group. Sclerenchyma strands are commonly associated with resin canals in Medullosa and related seed-fern genera, which are common in coal balls of the Illinois basin. We here propose adoption of the maceral varietal terms "sclerenchymo-fusinite" and "sclerenchymo-semifusinite" for these bodies. The woody splinters in the Pomeroy coal bed are cellular and thin-walled and have scattered pits as much as a few microns in diameter. They are dark brown to black in transmitted light and commonly have a lower reflectance than the resino-sclerotinite and sclerenchymo-fusinite of the Pomeroy coal. The woody splinters belong to semifusinite and fusinite of the inertinite maceral group. The maceral varietal terms "xylemo-semifusinite" and "xylemo-fusinite" are here proposed for these bodies. Elemental chemical data for the resin rodlets of the Pomeroy coal bed of the central Appalachian basin indicate that resin rodlets have significantly lower atomic H/C and O/C ratio

Stratigraphic framework of upper Paleozoic rocks, southeastern Sangre de Cristo Mountains, New Mexico

USGS Publications Warehouse

Baltz, E.H.; Myers, D.A.

1999-01-01

The Sangre de Cristo Mountains of south-central Colorado and north-central New Mexico are the physiographic expression of a southerly trending Cenozoic structural uplift that plunges gently south to die out in the Great Plains south of Santa Fe and Las Vegas, New Mexico. The uplift is bounded on the west by Neogene downfaulted and downwarped basins of the Rio Grande depression and, on the east, by broad Laramide basins that have sharply folded western limbs. The uplift was modified in Neogene time by local igneous-intrusive doming and normal faulting related to the Rio Grande rift.

ARNOLD MESA ROADLESS AREA, ARIZONA.

USGS Publications Warehouse

Wolfe, Edward W.; McColly, Robert A.

1984-01-01

Geologic geochemical, and aeromagnetic investigations and a survey of mines and prospects in the Arnold Mesa Roadless Area, Arizona, provide little evidence for the occurrence of mineral or energy resources. Buried Proterozoic basement rocks are possible hosts of porphyry-type copper and massive sulfide deposits but the thick cover of Paleozoic sedimentary rocks and upper Cenozoic volcanic rocks precluded assessment of this possibility. Chemistry and temperature of spring and well waters suggest that a geothermal resource may exist near the eastern margin of the roadless area, but the anomaly has not been tested by drilling and this resource remains unverified. No other energy resources were identified.

Geologic map of the Nelson quadrangle, Lewis and Clark County, Montana

USGS Publications Warehouse

Reynolds, Mitchell W.; Hays, William H.

2003-01-01

The geologic map of the Nelson quadrangle, scale 1:24,000, was prepared as part of the Montana Investigations Project to provide new information on the stratigraphy, structure, and geologic history of an area in the geologically complex southern part of the Montana disturbed belt. In the Nelson area, rocks ranging in age from Middle Proterozoic through Cretaceous are exposed on three major thrust plates in which rocks have been telescoped eastward. Rocks within the thrust plates are folded and broken by thrust faults of smaller displacement than the major bounding thrust faults. Middle and Late Tertiary sedimentary and volcaniclastic rocks unconformably overlie the pre-Tertiary rocks. A major normal fault displaces rocks of the western half of the quadrangle down on the west with respect to strata of the eastern part. Alluvial and terrace gravels and local landslide deposits are present in valley bottoms and on canyon walls in the deeply dissected terrain. Different stratigraphic successions are exposed at different structural levels across the quadrangle. In the northeastern part, strata of the Middle Cambrian Flathead Sandstone, Wolsey Shale, and Meagher Limestone, the Middle and Upper Cambrian Pilgrim Formation and Park Shale undivided, the Devonian Maywood, Jefferson, and lower part of the Three Forks Formation, and Lower and Upper Mississippian rocks assigned to the upper part of the Three Forks Formation and the overlying Lodgepole and Mission Canyon Limestones are complexly folded and faulted. These deformed strata are overlain structurally in the east-central part of the quadrangle by a succession of strata including the Middle Proterozoic Greyson Formation and the Paleozoic succession from the Flathead Sandstone upward through the Lodgepole Limestone. In the east-central area, the Flathead Sandstone rests unconformably on the middle part of the Greyson Formation. The north edge, northwest quarter, and south half of the quadrangle are underlain by a succession of rocks that includes not only strata equivalent to those of the remainder of the quadrangle, but also the Middle Proterozoic Newland, Greyson, and Spokane Formations, Pennsylvanian and Upper Mississippian Amsden Formation and Big Snowy Group undivided, the Permian and Pennsylvanian Phosphoria and Quadrant Formations undivided, the Jurassic Ellis Group and Lower Cretaceous Kootenai Formation. Hornblende diorite sills and irregular bodies of probable Late Cretaceous age intrude Middle Proterozoic, Cambrian and Devonian strata. No equivalent intrusive rocks are present in structurally underlying successions of strata. In this main part of the quadrangle, the Flathead Sandstone cuts unconformably downward from south to north across the Spokane Formation into the upper middle part of the Greyson Formation. Tertiary (Miocene?) strata including sandstone, pebble and cobble conglomerate, and vitric crystal tuff underlie, but are poorly exposed, in the southeastern part of the quadrangle where they are overlain by late Tertiary and Quaternary gravel. The structural complexity of the quadrangle decreases from northeast to southwest across the quadrangle. At the lowest structural level (Avalanche Butte thrust plate) exposed in the canyon of Beaver Creek, lower and middle Paleozoic rocks are folded in northwest-trending east-inclined disharmonic anticlines and synclines that are overlain by recumbently folded and thrust faulted Devonian and Mississippian rocks. The Mississippian strata are imbricated adjacent to the recumbent folds. In the east-central part of the quadrangle, a structurally overlying thrust plate, likely equivalent to the Hogback Mountain thrust plate of the Hogback Mountain quadrangle adjacent to the east (Reynolds, 20xx), juxtaposes recumbently folded Middle Proterozoic and unconformably overlying lower Paleozoic rocks on the complexly folded and faulted rocks of the Avalanche Butte thrust plate. The highest structural plate, bounded below

Paleozoic intrusive rocks from the Dunhuang tectonic belt, NW China: Constraints on the tectonic evolution of the southernmost Central Asian Orogenic Belt

NASA Astrophysics Data System (ADS)

Zhao, Yan; Sun, Yong; Diwu, Chunrong; Zhu, Tao; Ao, Wenhao; Zhang, Hong; Yan, Jianghao

2017-05-01

The Dunhuang tectonic belt (DTB) is of great importance for understanding the tectonic evolution of the southernmost Central Asian Orogenic Belt (CAOB). In this study, the temporal-spatial distribution, petrogenesis and tectonic setting of the Paleozoic representative intrusive rocks from the DTB were systematically investigated to discuss crustal evolution history and tectonic regime of the DTB during Paleozoic. Our results reveal that the Paleozoic magmatism within the DTB can be broadly divided into two distinct episodes of early Paleozoic and late Paleozoic. The early Paleozoic intrusive rocks, represented by a suite metaluminous-slight peraluminous and medium- to high-K calc-alkaline I-type granitoids crystallized at Silurian (ca. 430-410 Ma), are predominantly distributed along the northern part of the DTB. They were probably produced with mineral assemblage of eclogite or garnet + amphibole + rutile in the residue, and were derived from magma mixing source of depleted mantle materials with various proportions of Archean-Mesoproterozoic continental crust. The late Paleozoic intrusive rocks can be further subdivided into two stages of late Devonian stage (ca. 370-360 Ma) and middle Carboniferous stage (ca. 335-315 Ma). The former stage is predominated by metaluminous to slight peraluminous and low-K tholeiite to high-K calc-alkaline I-type granitic rocks distributed in the central part of the DTB. They were also generated with mineral assemblage of amphibolite- to eclogite-facies in the residue, and originated from magma source of depleted mantle materials mixed with different degrees of old continental crust. The later stage is represented by adakite and alkali-rich granite exposed in the southern part of the DTB. The alkali-rich granites studied in this paper were possibly produced with mineral assemblage of granulite-facies in the residue and were generated by partial melting of thickened lower continental crust. Zircon Hf isotopes and field distribution of those Paleozoic intrusive rocks reveal that both the Silurian and the late Devonian magmatic activities predominantly represent crustal growth processes in the DTB, accompanied by different degrees of reworking of pre-existing continental crust. However, the middle Carboniferous (ca. 335-315 Ma) magmatic activity reflects a crustal reworking process. The Silurian and late Devonian intrusive rocks were most likely formed in the arc-related subduction zones, whereas, the middle Carboniferous intrusive rocks were possibly formed in a transitional tectonic setting from compression to extension, representing the final stage of Paleozoic orogeny in the DTB. These Paleozoic magmatic rocks further suggest that the DTB has reactivated from a stable block to an orogen and undergone two episodes (the early Paleozoic and the late Paleozoic) of orogeny during Paleozoic. It represents a Paleozoic accretionary orogen of the southernmost margin of the CAOB between the Tarim Craton and North China Craton, and tectonically extends northward to the Beishan orogen and westward to the eastern South Tianshan Belt.

Dzhida Ore District: Geology, Structural and Metallogenic Regionalization, Genetic Types of Ore Deposits, Geodynamic Conditions of Their Formation, Forecast, and Outlook for Development

NASA Astrophysics Data System (ADS)

Gordienko, I. V.; Gorokhovsky, D. V.; Smirnova, O. K.; Lantseva, V. S.; Badmatsyrenova, R. A.; Orsoev, D. A.

2018-01-01

Based on complex structural, rheological, and metallogenic studies, taking into account the results of earlier subject-specific, prospecting, mapping, and exploration works, it has been established that the geological structure of the district was caused by the ensimatic evolution of the Vendian-Early Paleozoic Dzhida island-arc system, in which oceanic and island-arc complexes served as a melanocratic basement for Late Paleozoic-Mesozoic active within-plate (riftogenic) processes, which gave rise to the formation of ore deposits and occurrences of strategic mineral commodities (Mo, W, Au, Pt, Ag, and rare elements, including REE). Mantle plumes and flows of deep-seated transmagmatic solutions (ore-forming fluids) played a critical role in these processes, the significance of which increases in upper crustal swarms of dikes and fault systems. The forecasts and development prospects of the Dzhida ore district envisage the expansion of geological prospecting and exploration, scientific research, and technological testing of ore for insight into strategic mineral commodities, as well as reanimation of mining within the areas of the Dzhida's large territorial and industrial complex (TIC) in eastern Siberia.

Fracture overprinting history using Markov chain analysis: Windsor-Kennetcook subbasin, Maritimes Basin, Canada

NASA Astrophysics Data System (ADS)

Snyder, Morgan E.; Waldron, John W. F.

2018-03-01

The deformation history of the Upper Paleozoic Maritimes Basin, Atlantic Canada, can be partially unraveled by examining fractures (joints, veins, and faults) that are well exposed on the shorelines of the macrotidal Bay of Fundy, in subsurface core, and on image logs. Data were collected from coastal outcrops and well core across the Windsor-Kennetcook subbasin, a subbasin in the Maritimes Basin, using the circular scan-line and vertical scan-line methods in outcrop, and FMI Image log analysis of core. We use cross-cutting and abutting relationships between fractures to understand relative timing of fracturing, followed by a statistical test (Markov chain analysis) to separate groups of fractures. This analysis, previously used in sedimentology, was modified to statistically test the randomness of fracture timing relationships. The results of the Markov chain analysis suggest that fracture initiation can be attributed to movement along the Minas Fault Zone, an E-W fault system that bounds the Windsor-Kennetcook subbasin to the north. Four sets of fractures are related to dextral strike slip along the Minas Fault Zone in the late Paleozoic, and four sets are related to sinistral reactivation of the same boundary in the Mesozoic.

Mass Loss of Coal Particles Burning in Fluidized Bed

NASA Astrophysics Data System (ADS)

Pełka, Piotr

2017-06-01

In this work many conclusions resulting from research carried out on the coal combustion process of the chosen coal type and its accompanying erosion in a two-phase flow of inert material have been presented. The purpose of this flow was to present a model of the conditions of the central and upper zone of the combustion chamber of the fluidized boiler. In the opinion of many authors (Basu, 1999; Chirone et al., 1991), the erosion process results from the contact of a fuel particle with particles of inert material that is responsible for generating fine fuel particles of less than 100 mm. If the particles are in the upper zone of the boiler where there is oxygen deficit, they can increase the loss of incomplete combustion substantially. The results of research do not confirm this common thesis, but rather indicate that the process of comminution that results from erosion under oxidative conditions contributes to the increase of substantial mass loss of a coal particle, however the increased mass loss of particle during combustion is first and foremost due to the whole process of removal of ash from the reactionary surface of a fuel particle. Nevertheless, in the conditions of oxygen deficit the comminution of particles as a result of the erosion process is negligible

The coal-forming plants of the upper part of the Lower Cretaceous Starosuchan Formation (Partizansk Basin, South Primorye region)

NASA Astrophysics Data System (ADS)

Bugdaeva, E. V.; Markevich, V. S.; Volynets, E. B.

2014-05-01

The plant remains and palynological assemblages are studied in detail in the section of the coal-bearing upper part of the Aptian Starosuchan Formation near the village of Molchanovka (Partizansk Basin, South Primorye region). On the basis of the light and electron microscopic study of the disperse cuticles, it was established that the coals are mostly composed of remains of taxodialean Elatides asiatica (Yok.) Krassil., subordinate Miroviaceae, rare ginkgoalean Pseudotorellia sp., and bennettite Nilssoniopteris rithidorachis (Krysht.) Krassil. The spores Gleicheniidites and pollen Taxodiaceaepollenites are dominant in the palynospectrum of the coal interlayer. It was found that dominant taxodialeans and gleicheniaceous ferns with less abundant Miroviaceae, ginkgoaleans, and rare bennettites occurred in the Aptian swamp communities of the Partizansk basin. Shoots and leaves of Elatides asiatica, fronds of Birisia onychioides (Vassil. et K.-M.) Samyl., are dominant in the burials of plants from the clastic rocks. The fragments of leaves of Nilssoniopteris, scale-leaved conifers, and Ginkgo ex gr. adiantoides are rare. The disperse cuticle of these layers mostly includes Pseudotorellia sp.; however, its remains in burials were not found. The spores Laevigatosporites are dominant in the palynospectra from the clastic interlayers. Ginkgocycadophytus and taxa close to Pinaceae are plentiful among the pollen of gymnosperms.

Evaluation of the hydrologic system in the New Leipzig coal area, Grant and Hettinger counties, North Dakota

USGS Publications Warehouse

Armstrong, C.A.

1982-01-01

Aquifers in the New Leipzig coal area consist of sandstone beds in the Fox Hills Sandstone, the Hell Creek Formation, the Cannonball and Ludlow Members of the Fort Union Formation, and the basal part of the Tongue River Member of the Fort Union Formation. Aquifers also occur in sandstone and lignite beds in the upper part of the Tongue River Member and Sentinel Butte Member of the Fort Union Formation. Potential well yields from each of the aquifers are variable, but are less than 100 gallons per minute. Water in the Fox Hills, Hell Creek, Cannonball, and Ludlow is soft and of the sodium bicarbonate type. Water in basal Tongue River aquifer is either soft or very hard and generally is of the sodium bicarbonate type. Water in the upper Tongue River and Sentinel Butte aquifer system is very hard and generally is either of the calcium bicarbonate or sodium bicarbonate type. There is little or no contribution of ground water to Thirty Mile Creek or the Cannonball River from the area of minable coal. Coal mining will expose sulfide minerals to oxidation, and result in an increase in dissolved solids and sulfate in water in the basal Tongue River aquifer. (USGS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cebi, F.H.; Korkmaz, S.; Akcay, M.

The majority of coal deposits in the world are of Carboniferous and Tertiary age but Jurassic coals are seldom present. They are also exposed in northern Turkey and occur both at the lower and upper sections of the Liassic-Dogger volcanic- and volcani-clastic series. The coals at the base of the Jurassic units are characterized by higher Ba, Th, Zr, and Cr-Ni and lower S values than those at the top of the units, indicating, in general, laterally consistent trace element contents. The vertical distribution of trace elements in individual coal seams is also rather consistent. The B contents of coalsmore » from the Godul and Norsun areas vary from 1.5 to 4.3 ppm whereas those from the Alansa area are in the range of 95 to 138 ppm. This suggests that the coals in the Godul and Norsun areas were deposited in a swamp environment inundated by the sea from time to time, whereas coals of the Alansa were deposited in a saline environment.« less

Geologic map and upper Paleozoic stratigraphy of the Marble Canyon area, Cottonwood Canyon quadrangle, Death Valley National Park, Inyo County, California

USGS Publications Warehouse

Stone, Paul; Stevens, Calvin H.; Belasky, Paul; Montañez, Isabel P.; Martin, Lauren G.; Wardlaw, Bruce R.; Sandberg, Charles A.; Wan, Elmira; Olson, Holly A.; Priest, Susan S.

2014-01-01

This geologic map and pamphlet focus on the stratigraphy, depositional history, and paleogeographic significance of upper Paleozoic rocks exposed in the Marble Canyon area in Death Valley National Park, California. Bedrock exposed in this area is composed of Mississippian to lower Permian (Cisuralian) marine sedimentary rocks and the Jurassic Hunter Mountain Quartz Monzonite. These units are overlain by Tertiary and Quaternary nonmarine sedimentary deposits that include a previously unrecognized tuff to which we tentatively assign an age of late middle Miocene (~12 Ma) based on tephrochronologic analysis, in addition to the previously recognized Pliocene tuff of Mesquite Spring. Mississippian and Pennsylvanian rocks in the Marble Canyon area represent deposition on the western continental shelf of North America. Mississippian limestone units in the area (Tin Mountain, Stone Canyon, and Santa Rosa Hills Limestones) accumulated on the outer part of a broad carbonate platform that extended southwest across Nevada into east-central California. Carbonate sedimentation was interrupted by a major eustatic sea-level fall that has been interpreted to record the onset of late Paleozoic glaciation in southern Gondwana. Following a brief period of Late Mississippian clastic sedimentation (Indian Springs Formation), a rise in eustatic sea level led to establishment of a new carbonate platform that covered most of the area previously occupied by the Mississippian platform. The Pennsylvanian Bird Spring Formation at Marble Canyon makes up the outer platform component of ten third-order (1 to 5 m.y. duration) stratigraphic sequences recently defined for the regional platform succession. The regional paleogeography was fundamentally changed by major tectonic activity along the continental margin beginning in middle early Permian time. As a result, the Pennsylvanian carbonate shelf at Marble Canyon subsided and was disconformably overlain by lower Permian units (Osborne Canyon and Darwin Canyon Formations) representing part of a deep-water turbidite basin filled primarily by fine-grained siliciclastic sediment derived from cratonal sources to the east. Deformation and sedimentation along the western part of this basin continued into late Permian time. The culminating phase was part of a regionally extensive late Permian thrust system that included the Marble Canyon thrust fault just west of the present map area.

The potential source of lead in the Permian Kupferschiefer bed of Europe and some selected Paleozoic mineral deposits in the Federal Republic of Germany

USGS Publications Warehouse

Wedepohl, K.H.; Delevaux, M.H.; Doe, B.R.

1978-01-01

New lead isotopic compositions have been measured for Paleozoic bedded and vein ore deposits of Europe by the high precision thermal emission (triple filament) technique. Eleven samples have been analyzed from the Upper Permian Kupferschiefer bed with representatives from Poland to England, three samples from the Middle Devonian Rammelsberg deposit and one from the Middle Devonian Meggen deposit, both of which are conformable ore lenses and are in the Federal Republic of Germany (FRG); and also two vein deposits from the FRG were analyzed, from Ramsbeck in Devonian host rocks and from Grund in Carboniferous host rocks. For Kupferschiefer bed samples from Germany, the mineralization is of variable lead isotopic composition and appears to have been derived about 250 m.y. ago from 1700 m.y. old sources, or detritus of this age, in Paleozoic sedimentary rocks. Samples from England, Holland, and Poland have different isotopic characteristics from the German samples, indicative of significantly different source material (perhaps older). The isotopic variability of the samples from the Kupferschiefer bed in Germany probably favors the lead containing waters coming from shoreward (where poor mixing is to be expected) rather than basinward (where better mixing is likely) directions. The data thus support the interpretation of the metal source already given by Wedepohl in 1964. Data on samples from Rammelsberg and Meggen tend to be slightly less radiogenic than for the Kupferschiefer, about the amount expected if the leads were all derived from the same source material but 100 to 150 m.y. apart in time. The vein galena from Ramsbeck is similar to that from Rammelsberg conformable ore lenses, both in rocks of Devonian age; vein galena from Grund in Upper Carboniferous country rocks is similar to some bedded Kupferschiefer mineralization in Permian rocks, as if the lead composition was formed at about the same time and from similar source material as the bedded deposits. Although heat has played a more significant role in the formation of some of these deposits (veins and Rammelsberg-Meggen) than in others (Kupferschiefer), there is no indication of radically different sources for the lead, all apparently coming from sedimentary source material containing Precambrian detritus. One feldspar lead sample from the Brocken-Oker Granite is not the same in isotopic composition as any of the ores analyzed. ?? 1978 Springer-Verlag.

U-Pb Dating of Calcite to Constrain Basinal Brine Flux Events: An Example from the Upper Midwest USA

NASA Astrophysics Data System (ADS)

Rasbury, T.; Luczaj, J.

2017-12-01

Calcite forms in a variety of settings and can be the product of surface to deep basinal fluids. As such, this mineral can uniquely record details of the fluids responsible for its formation. The forms of calcium carbonates and their stratigraphic relationships from the thin section to the regional scale give important insights on pulses of fluids. A fundamental question is the age of such fluid pulses. While calcite excludes uranium (U) from its crystal structure, some is incorporated and depending on the U/Pb ratio, this provides an opportunity for radiometric dating. Calcite crystals of various sizes and crystal habits are found in Paleozoic carbonate rocks throughout the region from the western Michigan basin to the upper Mississippi valley. These are typically associated with Mississippi Valley-type (MVT) mineralization, including galena, sphalerite, and iron sulfides, but typically post-date the main MVT event. We have analyzed a variety of these calcites and find multiple generations of calcite, separated by tens of millions of years. The initial Pb isotope ratios are similar to the isotope ratios of nearby galena, strongly suggesting a genetic relationship. Our oldest ages are 200 Ma, and we find ages ranging into the Cenozoic. Based on the Paleozoic-hosted galena Pb-isotope isoscapes from the region, the fluids may have been sourced from both the Michigan and Illinois basins. An important and unanswered question is what would cause significant fluid movement out of the basins substantially after Appalachian orogenesis. Noble gas data from brines in the Michigan Basin have a mantle component and have been suggested to be responsible for recognized elevated temperatures across the basin (Ma et al., 2009). Multiple thermal events during the Paleozoic and Mesozoic eras may have an internal heat source related to reactivation of faults of the Keweenawan Rift system below the Michigan Basin. Perhaps a mantle heat source from below episodically fluxes into the basins and displaces brines with important ore metals out of the basin. More work on the calcites will help to establish the geographic extent of the various fluid pulses in the region, which will lead to an improved understanding of the sources and paths of these fluids.

Update on coal in Big Horn basin, Montana and Wyoming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, R.W.

1983-08-01

The Big Horn Coal basin is located within the topographic and structural basin of the same name and is defined by the limits of the Upper Cretaceous Mesaverde Formation in northwestern Wyoming and the Eagle Sandstone in south-central Montana. The coal in this basin ranges in rank from high volatile C bituminous (based primarily on resistance to weathering) to subbituminous B coal. In general, the Mesaverde and Eagle coals are highest in heat content, averaging over 10,500 Btu/lb; the Fort Union coals in the Red Lodge-Bear Creek and Grass Creek fields average about 10,200 Btu/lb and are second highest inmore » heating value. The Meeteetse Formation contains coals that average 9,800 Btu/lb, the lowest heating values in the basin. An average heating value for all coal in the basin is slightly less than 10,000 But/lb. The average sulfur content of all coals in this basin is less than 1%, with a range of 0.4 to 2.2%. Coal mining in the Big Horn Coal basin began in the late 1880s in the Red Lodge field and has continued to the present. Almost 53 million tons of coal have been mined in the basin; nearly 78% of this production (41 million tons) is from bituminous Fort Union coal beds in the Red Lodge-Bear Creek and Bridger coal fields, Montana. Original in-place resources for the Big Horn Coal basin are given by rank of coal: 1,265.12 million tons of bituminous coal resources have been calculated for the Silvertip field, Wyoming, and the Red Lodge-Bear Creek and Bridger fields, Montana; 563.78 million tons of subbituminous resources have been calculated for the remaining Wyoming coal fields.« less

Coal hydrogenation and deashing in ebullated bed catalytic reactor

DOEpatents

Huibers, Derk T. A.; Johanson, Edwin S.

1983-01-01

An improved process for hydrogenation of coal containing ash with agglomeration and removal of ash from an ebullated bed catalytic reactor to produce deashed hydrocarbon liquid and gas products. In the process, a flowable coal-oil slurry is reacted with hydrogen in an ebullated catalyst bed reaction zone at elevated temperature and pressure conditions. The upward velocity and viscosity of the reactor liquid are controlled so that a substantial portion of the ash released from the coal is agglomerated to form larger particles in the upper portion of the reactor above the catalyst bed, from which the agglomerated ash is separately withdrawn along with adhering reaction zone liquid. The resulting hydrogenated hydrocarbon effluent material product is phase separated to remove vapor fractions, after which any ash remaining in the liquid fraction can be removed to produce substantially ash-free coal-derived liquid products.

Testing of the 15-inch air-sparged hydrocyclone for fine coal flotation at the Homer City preparation plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, J.D.; Yi, Y.; Gopalakrishnan, S.

1993-12-31

Previous plant testing had been limited to the processing of minus 100 mesh classifier overflow (Upper Freeport Coal {approximately} 20% ash) with the 6-inch air-sparged hydrocyclone (ASH-6C) as reported at Coal Prep 92. The ASH-6C unit was found to provide separation efficiencies equivalent, or superior, to separations with the ASH-2C system. During the summer of 1992 the construction of the first 15-inch air-sparged hydrocyclone prototype was completed by the Advanced Processing Technologies, Inc. Installation at the Homer City Coal Preparation Plant was accomplished and testing began in October 1992. The ASH-15C unit can operate at a flowrate as high asmore » 1,000 gpm. Experimental results are reported with respect to capacity, combustible recovery and clean coal quality.« less

Mountain building processes during continent continent collision in the Uralides

NASA Astrophysics Data System (ADS)

Brown, D.; Juhlin, C.; Ayala, C.; Tryggvason, A.; Bea, F.; Alvarez-Marron, J.; Carbonell, R.; Seward, D.; Glasmacher, U.; Puchkov, V.; Perez-Estaun, A.

2008-08-01

Since the early 1990's the Paleozoic Uralide Orogen of Russia has been the target of a significant research initiative as part of EUROPROBE and GEODE, both European Science Foundation programmes. One of the main objectives of these research programmes was the determination of the tectonic processes that went into the formation of the orogen. In this review paper we focus on the Late Paleozoic continent-continent collision that took place between Laurussia and Kazakhstania. Research in the Uralides was concentrated around two deep seismic profiles crossing the orogen. These were accompanied by geological, geophysical, geochronological, geochemical, and low-temperature thermochronological studies. The seismic profiles demonstrate that the Uralides has an overall bivergent structural architecture, but with significantly different reflectivity characteristics from one tectonic zone to another. The integration of other types of data sets with the seismic data allows us to interpret what tectonic processes where responsible for the formation of the structural architecture, and when they were active. On the basis of these data, we suggest that the changes in the crustal-scale structural architecture indicate that there was significant partitioning of tectonothermal conditions and deformation from zone to zone across major fault systems, and between the lower and upper crust. Also, a number of the structural features revealed in the bivergent architecture of the orogen formed either in the Neoproterozoic or in the Paleozoic, prior to continent-continent collision. From the end of continent-continent collision to the present, low-temperature thermochronology suggests that the evolution of the Uralides has been dominated by erosion and slow exhumation. Despite some evidence for more recent topographic uplift, it has so far proven difficult to quantify it.

Reported middle Paleozoic fossils and new geochronological data from the southern and central Appalachians: Disposable outrageous hypothesis or justification for major revision of tectonic history

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatcher, R.D. Jr.

Recently published interpretations of fossil fragments from the Walden Creek Group (Ocoee Supergroup) suggesting that these rocks are middle Paleozoic (Devonian to Early Carboniferous), and new geochronological data that yield late Paleozoic age dates on rocks and major faults in the Blue Ridge and piedmont, if taken alone, would permit speculation that most of the deformation and metamorphism affecting this part of the orogen is Alleghanian. The two Ordovician clastic wedges (Sevier, Llanvirn, and Martinsburg, Caradoc-Ashgill) and the Carboniferous-Permian wedge(s), along with many radiometric ages on plutons, indicate uplift and sediment dispersal from the interior of the southern and centralmore » Appalachians (SCA) that may have resulted from Taconian and Alleghanian deformation. Combining the reproducible fossil evidence, including that from Alabama and a recently discovered crinoid fragment from the upper part of the Murphy belt sequence, with the most current geochronological data requires that peak metamorphism and penetrative deformation be at least Devonian or younger at the southwestern end of the orogen, and Late Ordovician or younger in the Carolinas and northern Georgia. Zircon ages reported from large thrust and dextral strike-slip faults bounding the Pine Mountain window indicate all of the faults there may be Alleghanian, except the younger sinistral Mesozoic faults, and requires that both metamorphism and penetrative deformation there also be Alleghanian. As in New England, the southern Appalachian Alleghanian metamorphic core is now known to be much more extensive. The older data require that the Taconian and perhaps the Acadian orogenies were significant events in the SCA, but these new data reconfirm the dominance of Alleghanian continent-continent collision processes here.« less

Regional stratigraphy and petroleum potential, Ghadames basin, Algeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Emme, J.J.; Sunderland, B.L.

1991-03-01

The Ghadames basin in east-central Algeria extends over 65,000 km{sup 2} (25,000 mi{sup 2}), of which 90% is covered by dunes of the eastern Erg. This intracratonic basin consists of up to 6000 m (20,000 ft) of dominantly clastic Paleozoic through Mesozoic strata. The Ghadames basin is part of a larger, composite basin complex (Ilizzi-Ghadames-Triassic basins) where Paleozoic strata have been truncated during a Hercynian erosional event and subsequently overlain by a northward-thickening wedge of Mesozoic sediments. Major reservoir rocks include Triassic sandstones that produce oil, gas, and condensate in the western Ghadames basin, Siluro-Devonian sandstones that produce mostly oilmore » in the shallower Ilizzi basin to the south, and Cambro-Ordovician orthoquartzites that produce oil at Hassi Messaoud to the northwest. Organic shales of the Silurian and Middle-Upper Devonian are considered primary source rocks. Paleozoic shales and Triassic evaporite/red bed sequences act as seals for hydrocarbon accumulations. The central Ghadames basin is underexplored, with less than one wildcat well/1700 km{sup 2} (one well/420,000 ac). Recent Devonian and Triassic oil discoveries below 3500 m (11,500 ft) indicate that deep oil potential exists. Exploration to date has concentrated on structural traps. Subcrop and facies trends indicate that potential for giant stratigraphic or combination traps exists for both Siluro-Devonian and Triassic intervals. Modern seismic acquisition and processing techniques in high dune areas can be used to successfully identify critical unconformity-bound sequences with significant stratigraphic trap potential. Advances in seismic and drilling technology combined with creative exploration should result in major petroleum discoveries in the Ghadames basin.« less

Electromagnetic study of lithospheric structure in Trans-European Suture Zone in Poland

NASA Astrophysics Data System (ADS)

Jóźwiak, Waldemar; Ślęzak, Katarzyna; Nowożyński, Krzysztof; Neska, Anne

2016-04-01

The area covered by magnetotelluric surveys in Poland is mostly related to the Trans-European Suture Zone (TESZ), the largest tectonic boundary in Europe. Numerous 1D, 2D, and pseudo-3D and 3D models of the electrical resistivity distribution were constructed, and a new interpretation method based on Horizontal Magnetic Tensor analysis has been applied recently. The results indicate that the TESZ is a lithospheric discontinuity and there are noticeable differences in geoelectric structures between the East European Craton (EEC), the transitional zone (TESZ), and the Paleozoic Platform (PP). The electromagnetic sounding is a very efficient tool for recognizing the lithospheric structure especially it helps in identification of important horizontal (or lateral) inhomogeneities in the crust. Due to our study we can clearly determine the areas of the East European Craton of high resistivity, Paleozoic Platform of somewhat lower resistivity value, and transitional TESZ of complicated structure. At the East European Craton, we observe very highly resistive lithosphere, reaching 220-240 km depth. Underneath, there is distinctly greater conductivity values, most probably resulting from partial melting of rocks; this layer may represent the asthenosphere. The resistivity of the lithosphere under the Paleozoic Platform is somewhat lower, and its thickness does not exceed 150 km. The properties of the lithosphere in the transition zone, under the TESZ, differ significantly. The presented models include prominent, NW-SE striking conductive lineaments. These structures, that related with the TESZ, lie at a depth of 10-30 km. They are located in a mid-crustal level and they reach the boundary of the EEC. The structures we initially connect to the Variscan Deformation Front (VDF) and the Caledonian Deformation Front (CDF). The differentiation of conductivity visible in the crust continues in the upper mantle.

Assessment of hydrocarbon source rock potential of Polish bituminous coals and carbonaceous shales

USGS Publications Warehouse

Kotarba, M.J.; Clayton, J.L.; Rice, D.D.; Wagner, M.

2002-01-01

We analyzed 40 coal samples and 45 carbonaceous shale samples of varying thermal maturity (vitrinite reflectance 0.59% to 4.28%) from the Upper Carboniferous coal-bearing strata of the Upper Silesian, Lower Silesian, and Lublin basins, Poland, to evaluate their potential for generation and expulsion of gaseous and liquid hydrocarbons. We evaluated source rock potential based on Rock-Eval pyrolysis yield, elemental composition (atomic H/C and O/C), and solvent extraction yields of bitumen. An attempt was made to relate maceral composition to these source rock parameters and to composition of the organic matter and likely biological precursors. A few carbonaceous shale samples contain sufficient generation potential (pyrolysis assay and elemental composition) to be considered potential source rocks, although the extractable hydrocarbon and bitumen yields are lower than those reported in previous studies for effective Type III source rocks. Most samples analysed contain insufficient capacity for generation of hydrocarbons to reach thresholds required for expulsion (primary migration) to occur. In view of these findings, it is improbable that any of the coals or carbonaceous shales at the sites sampled in our study would be capable of expelling commercial amounts of oil. Inasmuch as a few samples contained sufficient generation capacity to be considered potential source rocks, it is possible that some locations or stratigraphic zones within the coals and shales could have favourable potential, but could not be clearly delimited with the number of samples analysed in our study. Because of their high heteroatomic content and high amount of asphaltenes, the bitumens contained in the coals are less capable of generating hydrocarbons even under optimal thermal conditions than their counterpart bitumens in the shales which have a lower heteroatomic content. Published by Elsevier Science B.V.

Relationship of fluviodeltaic facies to coal deposition in the lower Fort Union formation (Palaeocene), south-western North Dakota

USGS Publications Warehouse

Belt, Edward S.; Flores, Romeo M.; Warwick, Peter D.; Conway, Kevin M.; Johnson, Kirk R.; Waskowitz, Robert S.; Rahmani, R.A.; Flores, Romeo M.

1984-01-01

Facies analysis of the Ludlow and Tongue River Members of the Palaeocene Fort Union Formation provides an understanding of the relationship between fluviodeltaic environments and associated coal deposition in the south-western Williston Basin. The Ludlow Member consists of high-constructive delta facies that interfinger with brackish-water tongues of the Cannonball Member of the Fort Union Formation. The lower part of the Ludlow Member was deposited on a lower delta plain that consisted of interdistributary crevasse and subdelta lobes. The upper part of the Ludlow Member was deposited in meander belts of the upper delta plain. The delta plain facies of the Ludlow Member is overlain by alluvial plain facies consisting of swamp, crevasse-lobe, lacustrine, and trunk meander belt deposits of the Tongue River Member. The Ludlow delta is believed to have been fed by fluvial systems that probably flowed from the Powder River Basin to the Williston Basin undeterred by the Cedar Creek Anticline. However, the evidence indicates that the Cedar Creek Anticline was prominent enough, during early Tongue River Member deposition, to cause the obstruction of the regional fluvial system flowing from the SW, and the formation of local drainage.The Ludlow Member contains 18 coal beds in the area studied, of which the T-Cross and Yule coals are as thick as 4 m (12 ft). Abandoned delta lobes served as platforms where coals formed, which in turn, were drowned by mainly fresh water and subordinate brackish water. Repetition of deltaic sedimentation, abandonment, and occupation by swamp led to preservation of the T-Cross and Oyster coals in areas as extensive as 260 km2 (< 100 miles2).

Geologic Cross Section D-D' Through the Appalachian Basin from the Findlay Arch, Sandusky County, Ohio, to the Valley and Ridge Province, Hardy County, West Virginia

USGS Publications Warehouse

Ryder, Robert T.; Crangle, Robert D.; Trippi, Michael H.; Swezey, Christopher S.; Lentz, Erika E.; Rowan, Elisabeth L.; Hope, Rebecca S.

2009-01-01

Geologic cross section D-D' is the second in a series of cross sections constructed by the U.S. Geological Survey to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section D-D' provides a regional view of the structural and stratigraphic framework of the Appalachian basin from the Findlay arch in northwestern Ohio to the Valley and Ridge province in eastern West Virginia, a distance of approximately 290 miles. The information shown on the cross section is based on geological and geophysical data from 13 deep drill holes, several of which penetrate the Paleozoic sedimentary rocks of the basin and bottom in Mesoproterozoic (Grenville-age) crystalline basement rocks. This cross section is a companion to cross section E-E' (Ryder and others, 2008) that is located about 25 to 50 mi to the southwest. Although specific petroleum systems in the Appalachian basin are not identified on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and preferred migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on information shown on the cross section. Cross section D-D' lacks the detail to illustrate key elements of coal systems (such as paleoclimate, coal quality, and coal rank), but it does provide a general geologic framework (stratigraphic units and general rock types) for the coal-bearing section. Also, cross section D-D' may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.

Mineralogy and geochemistry of boehmite-rich coals: New insights from the Haerwusu Surface Mine, Jungar Coalfield, Inner Mongolia, China

USGS Publications Warehouse

Dai, S.; Li, D.; Chou, C.-L.; Zhao, L.; Zhang, Y.; Ren, D.; Ma, Y.; Sun, Y.

2008-01-01

Boehmite-rich coal of Pennsylvanian age was discovered earlier at the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China. This paper reports new results on 29 bench samples of the no. 6 coal from a drill core from the adjacent Haerwusu Surface Mine, and provides new insights into the origin of the minerals and elements present. The results show that the proportion of inertinite in the no. 6 coal is higher than in other Late Paleozoic coals in northern China. Based on mineral proportions (boehmite to kaolinite ratio) and major element concentrations in the coal benches of the drill core, the no. 6 coal may be divided into five sections (I to V). Major minerals in Sections I and V are kaolinite. Sections II and IV are mainly kaolinite with a trace of boehmite, and Section III is high in boehmite. The boehmite is derived from bauxite in the weathered surface (Benxi Formation) in the sediment-source region. The no. 6 coal is rich in Al2O3 (8.89%), TiO2 (0.47%), Li (116????g/g), F (286????g/g), Ga (18????g/g), Se (6.1????g/g), Sr (350????g/g), Zr (268????g/g), REEs (172????g/g), Pb (30????g/g), and Th (17????g/g). The elements are classified into five associations by cluster analysis, i.e. Groups A, B, C, D, and E. Group A (ash-SiO2-Al2O3-Na2O-Li) and Group B (REE-Sc-In-Y-K2O-Rb-Zr-Hf-Cs-U-P2O5-Sr-Ba-Ge) are strongly correlated with ash yield and mainly have an inorganic affinity. The elements that are negatively or less strongly correlated with ash yield (with exceptions of Fe2O3, Be, V, and Ni) are grouped in the remaining three associations: Group C, Se-Pb-Hg-Th-TiO2-Bi-Nb-Ta-Cd-Sn; Group D, Co-Mo-Tl-Be-Ni-Sb-MgO-Re-Ga-W-Zn-V-Cr-F-Cu; and Group E, S-As-CaO-MnO-Fe2O3. Aluminum is mainly distributed in boehmite, followed by kaolinite. The high correlation coefficients of the Li-ash, Li-Al2O3, and Li-SiO2 pairs indicate that Li is related to the aluminosilicates in the coal. The boehmite-rich coal is high in gallium and F, which occur in boehmite and the organic matter. Selenium and Pb are mainly in epigenetic clausthalite fillings in fractures. The abundant rare earth elements in the coal benches were supplied from two sources: the bauxite on the weathered surface of the Benxi Formation and from adjacent partings by groundwater leaching during diagenesis. The light rare earth elements (LREEs) are more easily leached from the partings and incorporated into the organic matter than the heavy REEs, leading to a higher ratio of LREEs to HREEs in the coal benches than in the overlying partings. ?? 2008 Elsevier B.V. All rights reserved.

The source rock potential of the Karroo coals of the south western Rift Basin of Tanzania

NASA Astrophysics Data System (ADS)

Mpanju, F.; Ntomola, S.; Kagya, M.

For many years geoscientists believed that coals (Type III Kerogen) generate gas only. The geochemical study of Durand and Parrante ( Petrolum Geochemistry and Exploration of Europe, pp. 255-265, 1983) revealed that coals have reasonable potential for oil generation. On this basis forty outcrop samples of Lower and Upper Permian age, i.e. coals and carbonaceous shales, were collected from the south western Rift Basin of Tanzania. The aim of the study was to determine the richness, type, maturity and hydrocarbon potential of the above samples. These samples were subjected to both geochemical and petrological analyses. Geochemical analyses included solvent extraction, TOC, GC, GC-MS and pyrolysis. The petrological analysis included vitrinite reflectance, spore fluorescence and maceral content. The geochemical analyses showed all samples to be rich in organic matter of Types II and III and samples from Songwe Kiwira, Namwele, Mbamba Bay, Njuga and Mhukuru coalfields were in an early mature-mature stage of hydrocarbon generation. Whereas samples from Ketewaka and Ngaka coalfields showed a GC-trace of early generated waxy oil. All samples contained organic matter derived from terrestrial material which was deposited under oxic environment. The Hydrogen Index of most coals and carbonaceous shales was greater than 200 indicating that they can generate oil or light oil. Petrological observations showed all samples to be in the range of 0.47-0.67% Ro and some of them were rich in both liptinite and vitrinite macerals. From both geochemical and petrological observations it was concluded that the Lower and Upper Permian coals and carbonaceous shales under study are probably capable of generating oil. The oil generated has the same characteristics as that generated by Cretaceous and Tertiary coals discovered from other parts of the world, i.e. Adjuna and Kutei Basins in Indonesia and the Gippsland Basin in Australia (Kirkland et al., AAPG Bull.71, 577, 1987).

Partitioning of selected trace elements in coal combustion products from two coal-burning power plants in the United States

USGS Publications Warehouse

Swanson, Sharon M.; Engle, Mark A.; Ruppert, Leslie F.; Affolter, Ronald H.; Jones, Kevin B.

2013-01-01

Samples of feed coal (FC), bottom ash (BA), economizer fly ash (EFA), and fly ash (FA) were collected from power plants in the Central Appalachian basin and Colorado Plateau to determine the partitioning of As, Cr, Hg, Pb, and Se in coal combustion products (CCPs). The Appalachian plant burns a high-sulfur (about 3.9 wt.%) bituminous coal from the Upper Pennsylvanian Pittsburgh coal bed and operates with electrostatic precipitators (ESPs), with flue gas temperatures of about 163 °C in the ESPs. At this plant, As, Pb, Hg, and Se have the greatest median concentrations in FA samples, compared to BA and EFA. A mass balance (not including the FGD process) suggests that the following percentages of trace elements are captured in FA: As (48%), Cr (58%), Pb (54%), Se (20%), and Hg (2%). The relatively high temperatures of the flue gas in the ESPs and low amounts of unburned C in FA (0.5% loss-on-ignition for FA) may have led to the low amount of Hg captured in FA. The Colorado Plateau plant burns a blend of three low-S (about 0.74 wt.%) bituminous coals from the Upper Cretaceous Fruitland Formation and operates with fabric filters (FFs). Flue gas temperatures in the baghouses are about 104 °C. The elements As, Cr, Pb, Hg, and Se have the greatest median concentrations in the fine-grained fly ash product (FAP) produced by cyclone separators, compared to the other CCPs at this plant. The median concentration of Hg in FA (0.0983 ppm) at the Colorado Plateau plant is significantly higher than that for the Appalachian plant (0.0315 ppm); this higher concentration is related to the efficiency of FFs in Hg capture, the relatively low temperatures of flue gas in the baghouses (particularly in downstream compartments), and the amount of unburned C in FA (0.29% loss-on-ignition for FA).

Analysis of gob gas venthole production performances for strata gas control in longwall mining.

PubMed

Karacan, C Özgen

2015-10-01

Longwall mining of coal seams affects a large area of overburden by deforming it and creating stress-relief fractures, as well as bedding plane separations, as the mining face progresses. Stress-relief fractures and bedding plane separations are recognized as major pathways for gas migration from gas-bearing strata into sealed and active areas of the mines. In order for strata gas not to enter and inundate the ventilation system of a mine, gob gas ventholes (GGVs) can be used as a methane control measure. The aim of this paper is to analyze production performances of GGVs drilled over a longwall panel. These boreholes were drilled to control methane emissions from the Pratt group of coals due to stress-relief fracturing and bedding plane separations into a longwall mine operating in the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama. During the course of the study, Pratt coal's reservoir properties were integrated with production data of the GGVs. These data were analyzed by using material balance techniques to estimate radius of influence of GGVs, gas-in-place and coal pressures, as well as their variations during mining. The results show that the GGVs drilled to extract gas from the stress-relief zone of the Pratt coal interval is highly effective in removing gas from the Upper Pottsville Formation. The radii of influence of the GGVs were in the order of 330-380 m, exceeding the widths of the panels, due to bedding plane separations and stress relieved by fracturing. Material balance analyses indicated that the initial pressure of the Pratt coals, which was around 648 KPa when longwall mining started, decreased to approximately 150 KPa as the result of strata fracturing and production of released gas. Approximately 70% of the initial gas-in-place within the area of influence of the GGVs was captured during a period of one year.

Geology and mineral resources of central Antioquia Department (Zone IIA), Colombia

USGS Publications Warehouse

Hall, R.B.; Alvarez A., Jairo; Rico H., Hector

1973-01-01

This report summarizes the geology of an area of some 6000 square kilometers in the northern part of the Central Cordillera of the Colombian Andes. The area, in north-central Department of Antioquia, was mapped between 1964 and 1968 as part of the Inventario Minero Nacional (IMN) project. Mineral resources are summarized within a larger area, designated as subzone ILK of IMN Zone If, which comprises almost 22,000 sq. kin, including the area mapped geologically by IMN and additional areas mapped by other agencies. The oldest formation is a micaceous paragneiss of early Paleozoic or possibly late Precambrian age. A thick geosynclinal sedimentary series accumulated during the Paleozoic Era and became regionally metamorphosed to greenschist (locally amphibolite) facies during the Permian or early Triassic; these schists and gneisses are designated collectively as the Valdivia Group. The Permian(?) orogenic episode included intrusion of concordant syntectonic plutons, mostly of tonalitic composition. Rocks of unequivocal Triassic or Jurassic age are not recognized. The Cretaceous is well represented by both igneous and sedimentary assemblages. Eugeosynclinal alpine ophiolites comprising submarine basalt flows and numerous intrusions of gabbro and serpentinite are prominent in the Lower Cretaceous, together with flysch composed of marine shale and lesser sandstone and conglomerate. The Upper Cretaceous is represented along the west border of the mapped area by submarine basalt flows and pyroclastic rocks, locally Interbedded with fine-grained clastic sedimentary beds, and lenses of dark laminated chert, at least part of which is radiolarian. The Late Cretaceous was marked by an orogenic event that profoundly folded and faulted all rocks and in the Central Cordillera caused low-grade metamorphism, the overprint of which is hardly observable in pre-Cretaceous rocks elsewhere. The Late Cretaceous orogeny culminated with discordant intrusion of the epizonal tonalitic Antioquian batholith. Displacement along the great Romeral wrench fault may have begun in the Cretaceous. Plutonism continued into the Cenozoic, exemplified by the hornblende-diorite Sabanalarga pluton. Intermontane basins were filled with molasse derived from the erosion of adjacent highlands; Tertiary sedimentation in marshy areas included organic carboniferous matter subsequently converted to lignite or subbituminous coal. The Sabanalarga fault system originated in the Late Tertiary; intermittent displacement continued on the older wrench faults such as the Romeral. Epeirogenic uplift, which probably began in the Pliocene and continued through the Pleistocene and Holocene, brought on renewed erosion which has sculptured the mountains into their present form. Mineral resources in subzone IIA are varied but not of outstanding importance. Gold and silver mining, significant in past centuries, is minor today. Ferruginous laterite on serpentinite once considered as a potential source of iron ore is not economically exploitable. IMN has explored nickeliferous laterite at the extreme northwest corner of subzone IIA; this is a potential resource, exploitable only after exhaustion of the larger and richer nickel laterite deposit at Cerro Matoso, farther to the north and outside the boundaries of Zone If. Known deposits of mercury, chromium, manganese, and copper are small, with limited economic potential. Nonmetallic resources include raw materials for cement, including portland cement. Saprolite clay is widely used in making common red brick and tile, still a dominant construction material in all but the most modern multistory buildings. Aggregate materials are varied and abundant. Kaolin of good quality near La Union is important as a ceramic raw mineral filler. Tertiary subbituminous coal beds are an important energy resource in western subzone IIA, and have a good potential for greater development. Deposits of sodic feldspar, talc, decorative stone, and silica a

CO2 sequestration potential of Charqueadas coal field in Brazil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romanov, V; Santarosa, C; Crandall, D

2013-02-01

Although coal is not the primary source of energy in Brazil there is growing interest to evaluate the potential of coal from the south of the country for various activities. The I2B coal seamin the Charqueadas coal field has been considered a target for enhanced coal bed methane production and CO2 sequestration. A detailed experimental study of the samples from this seam was conducted at the NETL with assistance from the Pontif?cia Universidade Cat?lica Do Rio Grande Do Sul. Such properties as sorption capacity, internal structure of the samples, porosity and permeability were of primary interest in this characterization study.more » The samples used were low rank coals (high volatile bituminous and sub-bituminous) obtained from the I2B seam. It was observed that the temperature effect on adsorption capacity correlates negatively with as-received water and mineral content. Langmuir CO2 adsorption capacity of the coal samples ranged 0.61?2.09 mmol/g. The upper I2B seam appears to be overall more heterogeneous and less permeable than the lower I2B seam. The lower seam coal appears to have a large amount of micro-fractures that do not close even at 11 MPa of confining pressure.« less

Assessment of Possible Application of Geochemistry to Distinguish Limnic and Paralic Coal-Bearing Parts of the Carboniferous in the Upper Silesian Coal Basin

NASA Astrophysics Data System (ADS)

Kokowska-Pawłowska, Magdalena; Krzeszowska, Ewa

2017-12-01

The paper presents the results of geochemical analyses of samples from the Poruba Beds of the paralic series and from the Zaleskie Beds of the limnic series Upper Silesian Coal Basin (USCB). The contents of the following trace elements and oxides were evaluated using spectrometric method: Cr, Th, U, V, AL2O3, MgO, K2O, P2O5. The following indicators, most commonly used in chemostratigraphy and in the identification of the marine and non-marine sediments ratios, were analyzed: U, Th, Th/U, K2O, Th/K2O, P2O5, Al2O3, P2O5/ Al2O3, V, Cr, V/Cr, and (K2O/Al2O3) / (MgO/Al2O3). The research showed that those ratios may be used to identify sedimentary environments and geochemical correlations of the sedimentary rock sequences in the USCB. Geochemical ratios discussed in the paper allowed distinguishing two populations of samples representing paralic and limnic series.

Early Forest Soils and Their Role in Devonian Global Change

PubMed

Retallack

1997-04-25

A paleosol in the Middle Devonian Aztec Siltstone of Victoria Land, Antarctica, is the most ancient known soil of well-drained forest ecosystems. Clay enrichment and chemical weathering of subsurface horizons in this and other Devonian forested paleosols culminate a long-term increase initiated during the Silurian. From Silurian into Devonian time, red clayey calcareous paleosols show a greater volume of roots and a concomitant decline in the density of animal burrows. These trends parallel the decline in atmospheric carbon dioxide determined from isotopic records of pedogenic carbonate in these same paleosols. The drawdown of carbon dioxide began well before the Devonian appearance of coals, large logs, and diverse terrestrial plants and animals, and it did not correlate with temporal variation in volcanic or metamorphic activity. The early Paleozoic greenhouse may have been curbed by the evolution of rhizospheres with an increased ratio of primary to secondary production and by more effective silicate weathering during Silurian time.

Origin and tectonic evolution of early Paleozoic arc terranes abutting the northern margin of North China Craton

NASA Astrophysics Data System (ADS)

Zhou, Hao; Pei, Fu-Ping; Zhang, Ying; Zhou, Zhong-Biao; Xu, Wen-Liang; Wang, Zhi-Wei; Cao, Hua-Hua; Yang, Chuan

2017-12-01

The origin and tectonic evolution of the early Paleozoic arc terranes abutting the northern margin of the North China Craton (NCC) are widely debated. This paper presents detrital zircon U-Pb and Hf isotopic data of early Paleozoic strata in the Zhangjiatun arc terrane of central Jilin Province, northeast (NE) China, and compares them with the Bainaimiao and Jiangyu arc terranes abutting the northern margin of the NCC. Detrital zircons from early Paleozoic strata in three arc terranes exhibit comparable age groupings of 539-430, 1250-577, and 2800-1600 Ma. The Paleoproterozoic to Neoarchean ages and Hf isotopic composition of the detrital zircons imply the existence of the Precambrian fragments beneath the arc terranes. Given the evidences from geology, igneous rocks, and detrital zircons, we proposed that the early Paleozoic arc terranes abutting the northern margin of the NCC are a united arc terrane including the exotic Precambrian fragments, and these fragments shared a common evolutionary history from Neoproterozoic to early-middle Paleozoic.

Conodonts of the western Paleozoic and Triassic belt, Klamath Mountains, California and Oregon

USGS Publications Warehouse

Irwin, William P.; Wardlaw, Bruce R.; Kaplan, T.A.

1983-01-01

Conodonts were extracted from 32 samples of limestone and 5 samples of chert obtained from the Western Paleozoic and Triassic belt of the Klamath Mountains province. Triassic conodonts were found in 17 samples, and late Paleozoic conodonts in 7 samples. Conodonts of the remaining 13 samples cannot be dated more closely than early or middle Paleozoic through Triassic. The late Paleozoic conodonts are restricted to the North Fork and Hayfork terranes. The Hayfork terrane also contains Early, Middle, and Late Triassic conodonts; mostly Neogondolella. Conodonts from samples of the Rattlesnake Creek terrane and the northern undivided part of the belt are all Late Triassic and are generally Epigondolella. The conodont data support the concept that many of the limestone bodies are olistoliths or tectonic blocks in melange. Color alteration of the conodonts indicates that the rocks of the Western Paleozoic and Triassic belt have been heated to temperatures between 300 degrees and 500 degrees C during regional tectonism.

Interaction and the structures of coal

NASA Astrophysics Data System (ADS)

Opaprakasit, Pakorn

The origin of a decrease in the amount of soluble material from coal upon a reflux treatment has been investigated in an attempt to obtain insight into the nature of the interaction in the macromolecular network structure of coal. This decrease in the extractable material is a result of an increase in the amount of physical cross-links associated with secondary interactions. The alternate possibility of covalent cross-link formation by ether linkage was found to be unlikely because the coal hydroxyl content remains unchanged upon heat treatment. The functional groups responsible for forming these physical cross-links and their contents vary from coal to coal with coal rank. Carboxylate/cation complexes, similar to those found in ionomers, dominate in low rank coal. In high rank coal, the clusters involving pi-cation interactions were observed. Both mechanisms seem to play a role in mid rank coals. These physical cross-links are responsible for a lowering of the extraction yield of coal, but are disrupted by a treatment with acid solution, resulting in an increase in the extraction yield. As a consequence, the cross-links in coal structure should be classified into two types; a "permanent" covalent cross-link, which break under extreme conditions such as chemical reaction and pyrolysis, and "reversible" cross-links, largely associated with ionomer-like structure and pi-cation interactions. The interaction between a "magic" solvent of N-methylpyrollidone and carbon disulfide (NMP/CS2) and its role in the unusual extractability enhancement of Upper Freeport coal has also been investigated. The results strongly suggest that NMP/CS2 mixed solvents form complexes with cations. These mixed solvents are capable of forming a solid complex with cations from NaOH and some simple salts, such as NaCl and LiCl. Given that Upper Freeport coal contains a large amount of mineral matter, it is not surprising that these types of complexes could be formed in the present of the mixed solvents, which in turn enhances the coal extraction yield. Finally, the evidence for the presence of a glass transition temperature in coal was examined. The results from Differential Scanning Calorimetry showed that no transition similar to the Tg can be observed in bulk coal or its low-molecular weight fraction, pyridine soluble extracted material, at a temperature near 110°C. In contrast, an irreversible transition that is due to water evaporation has been found. Thermomechanical measurements, which are very sensitive to the presence of a Tg in synthetic polymers, also provided no evidence for a Tg below temperatures where chemical reactions occur. Additionally, the results from Thermomechanical Analysis showed an expansion in size when the coal was heated to 300°C, which is associated with a "caking" process. The degree of expansion during this "caking" process is about five times greater in the direction perpendicular to the bedding plane than the parallel, indicating an accommodation of anisotropic strain relaxation, which was generated in the direction perpendicular to the bedding plane during the coalification process.

Triggering effect of mining at different horizons in the rock mass with excavations. Mathematical modeling

NASA Astrophysics Data System (ADS)

Eremin, M. O.; Makarov, P. V.

2017-12-01

On the basis of a quite simple structural model of rock mass, containing coal seams on two horizons, coal mining is numerically modeled. A finite difference numerical technique is applied. At first, mining starts at the upper horizon and then moves to the lower horizon. It is shown that a mining process at the lower horizon has a significant triggering influence on the growth of damage zones in the roof and floor at the upper horizon. The features of spatiotemporal migration of deformation activity are studied numerically. Foci of large-scale fracture are located at the boundary of the seismic silence zone and the zone where the deformation activity migrates. This boundary has an additional characteristic: the maximum gradient of rock pressure is observed in this zone.

Marine origin of pyritic sulfur in the Lower Bakerstown coal bed, Castleman coal field, Maryland (U.S.A.)

USGS Publications Warehouse

Lyons, P.C.; Whelan, J.F.; Dulong, F.T.

1989-01-01

The amount, kind, distribution, and genesis of pyrite in the Lower Bakerstown coal bed in a 150 ?? 15 m area of the Bettinger mine, Castleman coal field, Maryland, were studied by various analytical techniques. The mined coal, which had a nonmarine roof rock, contained 1.4-2.8 wt.% total sulfur, generally much lower than the high-sulfur coal (> 3.0 wt.% total S) to the north, which is associated with marine roof rocks. Small-scale systematic and nonsystematic variations in total sulfur and pyrite distribution were found in the mined area. In the column sample, most of the pyrite was found in the upper 9 cm of the 69-cm-thick mined coal and occurred mainly as a pyrite lens containing cell fillings in seed-fern tissue (coal ball). As-bearing pyrite was detected by laser microprobe techniques in the cell walls of this tissue but not elsewhere in the column sample. This may indicate that the As was derived from decomposition of organic matter in the cell walls. The sulfur isotopic composition and distribution of pyrite in the coal are consistent with introduction of marine sulfate shortly after peat deposition, followed by bacterial reduction and pyrite precipitation. Epigenetic cleat pyrite in the coal is isotopically heavy, implying that later aqueous sulfate was 34S-enriched. ?? 1989.

Tar yields from low-temperature carbonization of coal facies from the Powder River Basin, Wyoming, USA

USGS Publications Warehouse

Stanton, Ronald W.; Warwick, Peter D.; Swanson, Sharon M.

2005-01-01

Tar yields from low-temperature carbonization correlate with the amount of crypto-eugelinite in samples selected to represent petrographically distinct coal facies of the Wyodak-Anderson coal zone. Tar yields from Fischer Assay range from <1 to 11 wt.% on a dry basis and correspond (r = 0.72) to crypto-eugelinite contents of the coal that range from 15 to 60 vol.%. Core and highwall samples were obtained from active surface mines in the Gillette field, Powder River Basin, Wyoming. Because the rank of the samples is essentially the same, differences in low-temperature carbonization yields are interpreted from compositional differences, particularly the crypto-eugelinite content. In the Wyodak-Anderson coal zone, crypto-eugelinite probably was derived from degraded humic matter which absorbed decomposition products from algae, fungi, bacteria, and liptinitic plant parts (materials possibly high in hydrogen). Previous modeling of the distribution of crypto-eugelinite in the discontinuous Wyodak-Anderson coal zone indicated that tar yields should be greater from coal composing the upper part and interior areas than from coal composing the lower parts and margins of the individual coal bodies. It is possible that hydrocarbon yields from natural coalification processes would be similar to yields obtained from laboratory pyrolysis. If so, the amount of crypto-eugelinite may also be an important characteristic when evaluating coal as source rock for migrated hydrocarbons.

Regional-scale geomechanical impact assessment of underground coal gasification by coupled 3D thermo-mechanical modeling

NASA Astrophysics Data System (ADS)

Otto, Christopher; Kempka, Thomas; Kapusta, Krzysztof; Stańczyk, Krzysztof

2016-04-01

Underground coal gasification (UCG) has the potential to increase the world-wide coal reserves by utilization of coal deposits not mineable by conventional methods. The UCG process involves combusting coal in situ to produce a high-calorific synthesis gas, which can be applied for electricity generation or chemical feedstock production. Apart from its high economic potentials, UCG may induce site-specific environmental impacts such as fault reactivation, induced seismicity and ground subsidence, potentially inducing groundwater pollution. Changes overburden hydraulic conductivity resulting from thermo-mechanical effects may introduce migration pathways for UCG contaminants. Due to the financial efforts associated with UCG field trials, numerical modeling has been an important methodology to study coupled processes considering UCG performance. Almost all previous UCG studies applied 1D or 2D models for that purpose, that do not allow to predict the performance of a commercial-scale UCG operation. Considering our previous findings, demonstrating that far-field models can be run at a higher computational efficiency by using temperature-independent thermo-mechanical parameters, representative coupled simulations based on complex 3D regional-scale models were employed in the present study. For that purpose, a coupled thermo-mechanical 3D model has been developed to investigate the environmental impacts of UCG based on a regional-scale of the Polish Wieczorek mine located in the Upper Silesian Coal Basin. The model size is 10 km × 10 km × 5 km with ten dipping lithological layers, a double fault and 25 UCG reactors. Six different numerical simulation scenarios were investigated, considering the transpressive stress regime present in that part of the Upper Silesian Coal Basin. Our simulation results demonstrate that the minimum distance between the UCG reactors is about the six-fold of the coal seam thickness to avoid hydraulic communication between the single UCG reactors. Fault reactivation resulting from fault shear and normal displacements is discussed under consideration of potentially induced seismicity. Here, the coupled simulation results indicate that seismic hazard during UCG operation remains negligible with a seismic moment magnitude of MW < 3.

Interfacial properties and coal cleaning in the LICADO process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi, S.M.B.

1986-01-01

The LICADO LIquid CArbon DiOxide process is currently being investigated as a new technique for cleaning coal. It relies on the relative wettability of clean coal and mineral particles between liquid CO/sub 2/ and water so that when liquid CO/sub 2/ is dispersed into a coal-water slurry, it tends to form agglomerates with the clean coal particles and float them to the liquid CO/sub 2/ phase. The mineral particles, on the other hand, remain in the aqueous phase as refuse. Since the surface/interfacial properties of fine coal particles play such an important role in this coal cleaning operation, an understandingmore » of their behavior becomes indispensable. In order to understand the separation mechanisms involved in the LICADO process, it is necessary to study the interfacial interactions occurring in the CO/sub 2/-water-coal system. It is believed that a relationship between the process performance and the wetting characteristics of the coal/refuse particles can be established. Upper Freeport -200 mesh coal from Indiana County, PA with 23.5% ash content was selected for the experimental work. A specially designed high pressure experimental unit, equipped with necessary optical and photographic accessories, was constructed for this study. Contact angles were also measured on the coal surface under two different sample pretreatment conditions: water-first-wet and liquid CO/sub 2/-first-wet. The results infer that an optimum mixing is necessary to provide sufficient shear force to expose the clean coal particles to the CO/sub 2/ droplets. The coal maceral and mineral association on the coal particle surface was determined based on the reflective grey level distinction between the mineral and Litho-type of various coal components.« less

Alaska coal geology, resources, and coalbed methane potential

USGS Publications Warehouse

Flores, Romeo M.; Stricker, Gary D.; Kinney, Scott A.

2004-01-01

Estimated Alaska coal resources are largely in Cretaceous and Tertiary rocks distributed in three major provinces. Northern Alaska-Slope, Central Alaska-Nenana, and Southern Alaska-Cook Inlet. Cretaceous resources, predominantly bituminous coal and lignite, are in the Northern Alaska-Slope coal province. Most of the Tertiary resources, mainly lignite to subbituminous coal with minor amounts of bituminous and semianthracite coals, are in the other two provinces. The combined measured, indicated, inferred, and hypothetical coal resources in the three areas are estimated to be 5,526 billion short tons (5,012 billion metric tons), which constitutes about 87 percent of Alaska's coal and surpasses the total coal resources of the conterminous United States by 40 percent. Coal mining has been intermittent in the Central Alaskan-Nenana and Southern Alaska-Cook Inlet coal provinces, with only a small fraction of the identified coal resource having been produced from some dozen underground and strip mines in these two provinces. Alaskan coal resources have a lower sulfur content (averaging 0.3 percent) than most coals in the conterminous United States are within or below the minimum sulfur value mandated by the 1990 Clean Air Act amendments. The identified resources are near existing and planned infrastructure to promote development, transportation, and marketing of this low-sulfur coal. The relatively short distances to countries in the west Pacific Rim make them more exportable to these countries than to the lower 48 States of the United States. Another untapped but potential resource of large magnitude is coalbed methane, which has been estimated to total 1,000 trillion cubic feet (28 trillion cubic meters) by T.N. Smith 1995, Coalbed methane potential for Alaska and drilling results for the upper Cook Inlet Basin: Intergas, May 15 - 19, 1995, Tuscaloosa, University of Alabama, p. 1 - 21.

National Coal Utilization Assessment. a preliminary assessment of the health and environmental effects of coal utilization in the Midwest. Volume I. Energy scenarios, technology characterizations, air and water resource impacts, and health effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1977-01-01

This report presents an initial evaluation of the major health and environmental issues associated with increased coal use in the six midwestern states of Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin. Using an integrated assessment approach, the evaluation proceeds from a base-line scenario of energy demand and facility siting for 1975-2020. Emphasis is placed on impacts from coal extraction, land reclamation, coal combustion for electrical generation, and coal gasification. The range of potential impacts and constraints is illustrated by a second scenario that represents an expected upper limit for coal utilization in Illinois. The following are among the more significantmore » issues identified and evaluated in this study: If environmental and related issues can be resolved, coal will continue to be a major source of energy for the Midwest; existing sulfur emission constraints will increase use of western coal; the resource requirements and environmental impacts of coal utilization will require major significant environmental and economic tradeoffs in site selection; short-term (24-hr) ambient standards for sulfur dioxide will limit the sizes of coal facilities or require advanced control technologies; an impact on public health may result from long-range transport of airborne sulfur emissions from coal facilities in the Midwest; inadequately controlled effluents from coal gasification may cause violations of water-quality standards; the major ecological effects of coal extraction are from pre-mining and post-reclamation land use; and sulfur dioxide is the major potential contributor to effects on vegetation of atmospheric emissions from coal facilities.« less

Geochemistry of rare earth elements in Permian coals from the Huaibei Coalfield, China

USGS Publications Warehouse

Zheng, Lingyun; Liu, Gaisheng; Chou, C.-L.; Qi, C.; Zhang, Y.

2007-01-01

The rare earth elements (REEs) in coals are important because of: (a) REE patterns can be an indicator of the nature of source rocks of the mineral matter as well as sedimentary environments; (b) REEs abundance in coal may have industrial-significance. In this study, a total of thirty-four samples of Permian coal, partings, roof, and floor were collected from the Huaibei Coalfield, Anhui Province, China. Abundances of rare earth elements (REEs) and other elements in the samples were determined by inductively coupled-plasma mass spectrometry (ICP-MS) and inductively coupled-plasma atomic emission spectrometry (ICP-AES). The results show that the REEs are enriched in coals in the Huaibei Coalfield as compared with Chinese and U.S. coals and the world coal average. Coals in the Lower Shihezi Formation (No. 7, 5, and 4 Coals) and Upper Shihezi Formation (No. 3) have higher REE abundances than the coals in Shanxi Formation (No. 10). Magmatic intrusion resulted in high enrichment of REEs concentrations in No. 5 and 7 Coals. The REE abundances are positively correlated with the ash content. The mineral matter in these coals is mainly made up of clay minerals and carbonates. The REEs are positively correlated with lithophile elements including Si, Al, Ti, Fe, and Na, which are mainly distributed in clay minerals, indicating that REEs are contained mainly in clay minerals. The REE abundances in coals normalized by the ash are higher than that in partings. REEs abundances of coals cannot be accounted for by the REE content in the mineral matter, and some REEs associated with organic matter in coals. ?? 2007 Elsevier Ltd. All rights reserved.

A resolution honoring the coal miners who perished in the Upper Big Branch Mine-South in Raleigh County, West Virginia, extending the condolences of the United States Senate to the families of the fallen coal miners, and recognizing the valiant efforts of the emergency response workers.

THOMAS, 111th Congress

Sen. Byrd, Robert C. [D-WV

2010-04-15

Senate - 04/15/2010 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

Documentation of the appearance of a caviar-type deposit in Oven 1 following a large scale experiment for heating oil with Upper Silesian coal (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rank

1942-03-26

When the oven was disassembled after the test, small kernels of porous material were found in both the upper and lower portion of the oven to a depth of about 2 m. The kernels were of various sizes up to 4 mm. From 1,300 metric ..cap alpha..ons of dry coal, there were 330 kg or the residue of 0.025% of the coal input. These kernels brought to mind deposits of spheroidal material termed ''caviar'', since they had rounded tops. However, they were irregularly long. After multiaxis micrography, no growth rings were found as in Leuna's lignite caviar. So, it wasmore » a question of small particles consisting almost totally of ash. The majority of the composition was Al, Fe, Na, silicic acid, S and Cl. The sulfur was found to be in sulfide form and Cl in a volatile form. The remains did not turn to caviar form since the CaO content was slight. The Al, Fe, Na, silicic acid, S and Cl were concentrated in comparison to coal ash and originate apparently from the catalysts (FeSO/sub 4/, Bayermasse, and Na/sub 2/S). It was notable that the Cl content was so high. 2 graphs, 1 table« less

Hydrologic assessment of the Upper Dorr Run Watershed, Hocking County, Ohio, 1998

USGS Publications Warehouse

Haefner, R.J.

1999-01-01

The Upper Dorr Run Watershed in Hocking County, Ohio, has been mined several times for coal and clay since 1913 and is a significant source of acid mine drainage to the Hocking River. To assess the surface-water hydrology of the site, a topographic map showing the location of springs and other hydrologic features of interest was prepared using aerial photography and field surveying and mapping techniques. Discharge and water-quality measurements at six springs and one stream site were made during field investigations in June 1998. Discharge and water quality observed at a downstream weir on Upper Dorr Run represents the combined discharge from springs plus ground-water inflow. Discharges from springs to surface water were generally small (less than 0.3 cubic foot per second), but one spring constituted 56 percent of the total discharge measured at the downstream weir. The total flow at an intermediate measurement site was less than the combined discharge of the upgradient springs because of evaporation, transpiration, and ground-water flow beneath the stream channel. The total flow at the weir was greater than the combined discharge of all springs, primarily because two potential sources of water were not included in field measurements. The water quality in Upper Dorr Run is strongly affected by acid mine drainage as indicated by pH less than 4, elevated acidity, and elevated concentrations of dissolved sulfate and dissolved iron. Concentrations of chemical constituents in the water were lower at the downstream weir than at the source springs because of residence times in ponds and chemical interactions between the water and the atmosphere. Acidity loads during the sampling period were significantly higher from the Lower Kittanning (No. 5) coal (272 kilograms per day) than from the Upper Kittanning (No. 6) coal (17.7 kilograms per day). Comparison of data obtained in 1998 to data obtained in 1982 showed that quality of water of selected sampling sites had not changed appreciably in 16 years.

Preliminary report on the coal resources of the National Petroleum Reserve in Alaska

USGS Publications Warehouse

Martin, G.C.; Callahan, J.E.

1978-01-01

NPR-A, located on the Arctic slope of Northern Alaska, is underlain by a thick sequence of sedimentary rocks of Cretaceous age which attain a thickness of as much as 4600 m (15,000 feet). The bulk of the coal resources occurs in rocks of the Nanushuk Group of Early and Late Cretaceous age. The Nanushuk Group is a wedge-shaped unit of marginal marine and nonmarine rocks that is as thick as 3300 m (11,000 feet) just west of NPR-A. Within the reserve, coal occurs primarily in the middle and thicker portions of this clastic wedge and occurs stratigraphically in the upper half of the section. Specific data on individual coal beds or zones are scarce, and estimates of identified coal resources of about 49.5 billion tons represent a sampling of coal resources too small to give a realistic indication of the potential resources for an area so large. Estimates of undiscovered resources suggest hypothetical resources of between 330 billion and 3.3 trillion tons. The wide range in the undiscovered resource estimates reflects the scarcity and ambiguity of the available data but also suggests the presence of a potentially large coal resource.

Analysis of hard coal quality for narrow size fraction under 20 mm

NASA Astrophysics Data System (ADS)

Niedoba, Tomasz; Pięta, Paulina

2018-01-01

The paper presents the results of an analysis of hard coal quality diversion in narrow size fraction by using taxonomic methods. Raw material samples were collected in selected mines of Upper Silesian Industrial Region and they were classified according to the Polish classification as types 31, 34.2 and 35. Then, each size fraction was characterized in terms of the following properties: density, ash content, calorific content, volatile content, total sulfur content and analytical moisture. As a result of the analysis it can be stated that the best quality in the entire range of the tested size fractions was the 34.2 coking coal type. At the same time, in terms of price parameters, high quality of raw material characterised the following size fractions: 0-6.3 mm of 31 energetic coal type and 0-3.15 mm of 35 coking coal type. The methods of grouping (Ward's method) and agglomeration (k-means method) have shown that the size fraction below 10 mm was characterized by higher quality in all the analyzed hard coal types. However, the selected taxonomic methods do not make it possible to identify individual size fraction or hard coal types based on chosen parameters.

Did the Middlesboro, Kentucky, bolide impact event influence coal rank?

USGS Publications Warehouse

Hower, J.C.; Greb, S.F.; Kuehn, K.W.; Eble, C.F.

2009-01-01

The Middlesboro Basin, southeastern Kentucky, occurs on the Cumberland Overthrust Sheet and includes a ca. 5.5-km diameter impact structure. The Lower and Middle Pennsylvanian coal-bearing strata are faulted, with some evidence for shock metamorphism. The event post-dated the latest-Pennsylvanian-early-Permian thrusting and was likely prior to late-Mesozoic entrenchment of drainages. The impact of a 0.5-km meteor traveling at ca. 60,000??km/h would release about 1??EJ, the approximate equivalent of the instantaneous combustion of 30??Mt of coal. The coal rank, while increased slightly above the regional level, still is within the upper portion of the high volatile A bituminous rank range. This helps to constrain the depth of burial at the time of the impact. The coal would have had to have been at a depth of a few kilometers to have avoided a more substantial rank increase. In addition, it is possible that some of the coal rank increase might be attributable to movements along the cross-cutting Rocky Face fault, unrelated to the impact. ?? 2009 Elsevier B.V. All rights reserved.

Passive margins: U.S. Geological Survey Line 19 across the Georges Bank basin

USGS Publications Warehouse

Klitgord, Kim D.; Schlee, John S.; Grow, John A.; Bally, A.W.

1987-01-01

Georges Bank is a shallow part of the Atlantic continental shelf southeast of New England (Emery and Uchupi, 1972, 1984). This bank, however, is merely the upper surface of several sedimentary basins overlying a block-faulted basement of igneous and metamorphic crystalline rock. Sedimentary rock forms a seaward-thickening cover that has accumulated in one main depocenter and several ancillary depressions, adjacent to shallow basement platforms of paleozoic and older crystalline rock. Georges Bank basin contains a thickness of sedimentary rock greater than 10 km, whereas the basement platforms that flank the basin are areas of thin sediment accumulation (less than 5 km).

Quantifying methane emissions from coal and natural gas sources along the northwestern Appalachian

NASA Astrophysics Data System (ADS)

Barkley, Z.; Lauvaux, T.; Davis, K. J.; Fried, A.

2017-12-01

According to the EPA's 2012 gridded inventory (Maasakkers et al., 2016), more than 10% of all CH4 emissions in the U.S. are located along the western edge of the Appalachian with the majority of these emissions coming from natural gas infrastructure and coal mines. However, top-down studies of unconventional wells in southwestern Pennsylvania have found emission rates to be much higher than EPA estimates (Caulton et al., 2014, Ren et al., 2017). Furthermore, although 9 of the 10 largest sources of CH4 in the EPA Greenhouse Gas Reporting Program are coal mines located in this region, no top down studies have been performed to assess the accuracy of these enormous point sources. This study uses aircraft data from the ACT-America flight campaign in conjunction with techniques previously used to solve for CH4 emissions from the northeastern Marcellus (Barkley et al., 2017) to quantify the total CH4 flux from the western Pennsylvania/West Virginia region and constrain emissions from natural gas and coal with an upper limit for each source. We use the WRF-Chem mesoscale model at 3 km resolution to simulate CH4 enhancements from a customized emissions inventory and compare the modelled enhancements to observations from 7 flights that were downwind of coal and gas sources. Coal and natural gas emissions are adjusted in the model to minimize a cost function that accounts for the difference between the modelled and observed CH4 values, and a range of likely combinations for natural gas and coal emission rates are obtained for each flight. We then overlap this range of likely emission rates across all flights to further limit the range of possible emission rates. Influence functions created using a lagrangian particle dispersion model for segments of each flight provide information on what area emissions are being optimized for. Preliminary results find that CH4 emissions from gas and coal along the northwestern Appalachian are lower than EPA estimates by 20-50%. In particular, upper limits on CH4 emissions from unconventional natural gas are less than 1% of total production, significantly lower than previous top-down estimates in the region. Future work will use ethane data to better distinguish between coal and natural gas emissions, and expand these analyses to other study regions explored in the ACT-America aircraft campaign.

Geochemical evidence for Paleozoic crustal growth and tectonic conversion in the Northern Beishan Orogenic Belt, southern Central Asian Orogenic Belt

NASA Astrophysics Data System (ADS)

Yuan, Yu; Zong, Keqing; He, Zhenyu; Klemd, Reiner; Jiang, Hongying; Zhang, Wen; Liu, Yongsheng; Hu, Zhaochu; Zhang, Zeming

2018-03-01

The Beishan Orogenic Belt is located in the central southernmost part of the Central Asian Orogenic Belt (CAOB), which plays a key role in understanding the formation and evolution of the CAOB. Granitoids are the documents of crustal and tectonic evolution in orogenic belts. However, little is known regarding the petrogenesis and geodynamic setting of the widely distributed Paleozoic granitoids in the Northern Beishan Orogenic Belt (NBOB). The present study reveals significant differences concerning the petrogenesis and tectonic setting of early and late Paleozoic granitoids from the NBOB. The early Paleozoic granitoids from the 446-430 Ma Hongliuxia granite complex of the Mazongshan unit and the 466-428 Ma Shibanjing complex of the Hanshan unit show classic I-type granite affinities as revealed by the relative enrichment of LILEs and LREEs, pronounced depletions of Nb, Ta and Ti and the abundant presence of hornblende. Furthermore, they are characterized by strongly variable zircon εHf(t) values between - 16.7 and + 12.8 and evolved plagioclase Sr isotopic compositions of 0.7145-0.7253, indicating the involvement of both juvenile and ancient continental crust in the magma source. Thus, we propose that the early Paleozoic granitoids in the NBOB were generated in a subduction-related continental arc setting. In contrast, the late Paleozoic 330-281 Ma granitoids from the Shuangjingzi complex of the Hanshan unit exhibit positive zircon εHf(t) values between + 5.8 and + 13.2 and relatively depleted plagioclase Sr isotopic compositions of 0.7037-0.7072, indicating that they were mainly formed by remelting of juvenile crust. Thus, an intra-plate extensional setting is proposed to have occurred during formation of the late Paleozoic granitoids. Therefore, between the early and late Paleozoic, the magma sources of the NBOB granitoids converted from the reworking of both juvenile and ancient crusts during a subduction-induced compressional setting to the remelting of juvenile crust during an intra-plate extensional setting, respectively. The corresponding crustal growth in the southern CAOB is dominated by early Paleozoic lateral accretion of arc complexes and late Paleozoic vertical addition of juvenile material from the mantle.

Late Paleozoic orogeny in Alaska's Farewell terrane

USGS Publications Warehouse

Bradley, D.C.; Dumoulin, Julie A.; Layer, P.; Sunderlin, D.; Roeske, S.; McClelland, B.; Harris, A.G.; Abbott, G.; Bundtzen, T.; Kusky, T.

2003-01-01

Evidence is presented for a previously unrecognized late Paleozoic orogeny in two parts of Alaska's Farewell terrane, an event that has not entered into published scenarios for the assembly of Alaska. The Farewell terrane was long regarded as a piece of the early Paleozoic passive margin of western Canada, but is now thought, instead, to have lain between the Siberian and Laurentian (North American) cratons during the early Paleozoic. Evidence for a late Paleozoic orogeny comes from two belts located 100-200 km apart. In the northern belt, metamorphic rocks dated at 284-285 Ma (three 40Ar/39Ar white-mica plateau ages) provide the main evidence for orogeny. The metamorphic rocks are interpreted as part of the hinterland of a late Paleozoic mountain belt, which we name the Browns Fork orogen. In the southern belt, thick accumulations of Pennsylvanian-Permian conglomerate and sandstone provide the main evidence for orogeny. These strata are interpreted as the eroded and deformed remnants of a late Paleozoic foreland basin, which we name the Dall Basin. We suggest that the Browns Fork orogen and Dall Basin comprise a matched pair formed during collision between the Farewell terrane and rocks to the west. The colliding object is largely buried beneath Late Cretaceous flysch to the west of the Farewell terrane, but may have included parts of the so-called Innoko terrane. The late Paleozoic convergent plate boundary represented by the Browns Fork orogen likely connected with other zones of plate convergence now located in Russia, elsewhere in Alaska, and in western Canada. Published by Elsevier B.V.

Hydrology and subsidence potential of proposed coal-lease tracts in Delta County, Colorado

USGS Publications Warehouse

Brooks, Tom

1983-01-01

Potential subsidence from underground coal mining and associated hydrologic impacts were investigated at two coal-lease tracts in Delta County, Colorado. Alteration of existing flow systems could affect water users in the surrounding area. The Mesaverde Formation transmits little ground water because of the neglibile transmissivity of the 1,300 feet of fine-grained sandstone, coal , and shale comprising the formation. The transmissivities of coal beds within the lower Mesaverde Formation ranged from 1.5 to 16.7 feet squared per day, and the transmissivity of the upper Mesaverde Formation, based on a single test, was 0.33 foot squared per day. Transmissivities of the alluvium ranged from 108 to 230 feet squared per day. The transmissivity of unconsolidated Quaternary deposits, determined from an aquifer test, was about 1,900 feet squared per day. Mining beneath Stevens Gulch and East Roatcap Creek could produce surface expressions of subsidence. Subsidence fractures could partly drain alluvial valley aquifers or streamflow in these mines. (USGS)

Integration of advanced preparation with coal liquefaction. Second quarterly technical progress report, January 1-March 31, 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steedman, W.G.; Longanbach, J.R.; Muralidhara, H.S.

Standard reaction conditions of 427 C, 5 minutes reaction time, 2:1 solvent/coal ratio and 1000 psig (r.t.) hydrogen overpressure result in good, but not maximum, conversions to THF soluble with both Illinois No. 6 and Wyodak (upper seam) coals. The cumulative effects of the pretreatment steps were also examined using feedstocks which were dried in a vacuum oven at room temperature under nitrogen before liquefaction to remove the effects of moisture. Chloride removal followed by drying had a positive effect on liquefaction. Oil agglomeration followed by drying also improved liquefaction reactivity significantly. Solvent drying also resulted in a small increasemore » in liquefaction reactivity. The overall reactivity of coal treated in sequence with each pretreatment step was slightly less than that of the dry ground coal. Liquefaction under a high partial pressure of hydrogen sulfide in hydrogen also results in a significant increase in conversion to THF solubles. 1 reference, 12 figures, 7 tables.« less

Lower Paleozoic deep-water facies of the Medfra area, central Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1997

USGS Publications Warehouse

Dumoulin, Julie A.; Bradley, Dwight C.; Harris, Anita G.; Repetski, John E.

1999-01-01

Deep-water facies, chiefly hemipelagic deposits and turbidites, of Cambrian through Devonian age are widely exposed in the Medfra and Mt. McKinley quadrangles. These strata include the upper part of the Telsitna Formation (Middle-Upper Ordovician) and the Paradise Fork Formation (Lower Silurian-Lower Devonian) in the Nixon Fork terrane, the East Fork Hills Formation (Upper Cambrian-Lower Devonian) in the East Fork subterrane of the Minchumina terrane, and the chert and argillite unit (Ordovician) and the argillite and quartzite unit (Silurian- Devonian? and possibly older) in the Telida subterrane of the Minchumina terrane.In the western part of the study area (Medfra quadrangle), both hemipelagic deposits and turbidites are largely calcareous and were derived from the Nixon Fork carbonate platform. East- ern exposures (Mt. McKinley quadrangle; eastern part of the Telida subterrane) contain much less carbonate; hemipelagic strata are mostly chert, and turbidites contain abundant rounded quartz and lesser plagioclase and potassium feldspar. Deep-water facies in the Medfra quadrangle correlate well with rocks of the Dillinger terrane exposed to the south (McGrath quadrangle), but coeval strata in the Mt. McKinley quadrangle are compositionally similar to rocks to the northeast (Livengood quadrangle). Petrographic data thus suggest that the Telida subterranes presently defined is an artificial construct made up of two distinct sequences of disparate provenance.Restoration of 90 and 150 km of dextral strike-slip on the Iditarod and Farewell faults, respectively, aligns the deep-water strata of the Minchumina and Dillinger terranes in a position east of the Nixon Fork carbonate platform. This restoration supports the interpretation that lower Paleozoic rocks in the Nixon Fork and Dillinger terranes, and in the western part of the Minchumina terrane (East Fork subterrane and western part of the Telida subterrane), formed along a single continental margin. Rocks in the eastern part of the Telida subterrane are compositionally distinct from those to the west and may have had a different origin and history.

Provenance implications of Th U Pb electron microprobe ages from detrital monazite in the Carboniferous Upper Silesia Coal Basin, Poland

NASA Astrophysics Data System (ADS)

Kusiak, Monika Agnieszka; Kędzior, Artur; Paszkowski, Mariusz; Suzuki, Kazuhiro; González-Álvarez, Ignacio; Wajsprych, Bolesław; Doktor, Marek

2006-05-01

This paper reports the results of CHIME (chemical Th-U-Pb isochron method) dating of detrital monazites from Carboniferous sandstones in the Upper Silesia Coal Basin (USCB). A total of 4739 spots on 863 monazite grains were analyzed from samples of sandstone derived from six stratigraphic units in the sedimentary sequence. Age distributions were identified in detrital monazites from the USCB sequence and correlated with specific dated domains in potential source areas. Most monazites in all samples yielded ca. 300-320 Ma (Variscan) ages; however, eo-Variscan, Caledonian and Cadomian ages were also obtained. The predominant ages are comparable to reported ages of certain tectonostratigraphic domains in the polyorogenic Bohemian Massif (BM), which suggests that various crystalline lithologies in the BM were the dominant sources of USCB sediments.

Exploration in Ordovician of central Michigan Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisher, J.H.; Barratt, M.W.

1985-12-01

Deep wells in the central Michigan basin have provided sufficient data to define two new mappable formations - the Foster Formation and the Bruggers Formation. Recent conodont studies have corrected the age assignments of the strata containing these formations. Previously, the lower section (Foster) was classified as mostly Cambrian, and the upper unit (Bruggers) was identified as Early Ordovician. Conodont identifications indicate an Early and Middle Ordovician age for the Foster Formation and a Middle Ordovician age for the Bruggers Formation. The Michigan basin existed in embryonic form in the Late Cambrian, but the full outline of the present-day basinmore » did not develop until Early Ordovician. Gas and condensate are produced from the Bruggers Formation as deep as 11,252 ft (3429 m). Geothermal investigations suggest that gas production is possible to the base of the Paleozoic section in the central basin (17,000 ft or 5181 m). Paleotemperatures were higher during the Paleozoic owing to 3000-4000 ft (914-1291 m) of additional sedimentary cover. Five wells are producing from the Bruggers Formation. All are deeper tests in anticlines producing from Devonian reservoirs discovered earlier. The structures are the result of vertical movements of basement fault blocks activated by regional stresses. 12 figures, 2 tables.« less

Regional trends in radiogenic heat generation in the Precambrian basement of the Western Canadian Basin

NASA Astrophysics Data System (ADS)

Jones, F. W.; Majorowicz, J. A.

Radiogenic heat generation values for 381 basement samples from 229 sites in the western Canadian basin exhibit a lognormal frequency distribution. The mean value = 2.06 (S.D. = 1.22) µWm-3 is larger than the radiogenic heat generation values reported for the shield in the Superior (ca. 1.2 µWm-3, Jessop and Lewis, 1978) and Churchill (ca. 0.7 µWm-3, Drury, 1985) provinces. When equal Log A contour intervals are used to map the basement heat generation, three large zones of relatively high heat generation are found. One coincides with the Peace River Arch basement structure and one with the Athabasca axis (Darnley, 1981). There is no apparent indication of increased heat flow through the Paleozoic formations associated with these two zones. The third zone, in southwestern Saskatchewan, coincides with a high heat flow zone in the Swift Current area. The lack of correlation between heat flow and heat generation in Alberta may be due to the disturbance to the heat flow in the Paleozoic formations by water motion, or may indicate that the heat is from uranium, thorium and potassium isotope enrichment near the basement surface rather than enrichment throughout the entire upper crust.

Braided fluvial sedimentation in the lower paleozoic cape basin, South Africa

NASA Astrophysics Data System (ADS)

Vos, Richard G.; Tankard, Anthony J.

1981-07-01

Lower Paleozoic braided stream deposits from the Piekenier Formation in the Cape Province, South Africa, provide information on lateral and vertical facies variability in an alluvial plain complex influenced by a moderate to high runoff. Four braided stream facies are recognized on the basis of distinct lithologies and assemblages of sedimentary structures. A lower facies, dominated by upward-fining conglomerate to sandstone and mudstone channel fill sequences, is interpreted as a middle to lower alluvial plain deposit with significant suspended load sedimentation in areas of moderate to low gradients. These deposits are succeeded by longitudinal conglomerate bars which are attributed to middle to upper alluvial plain sedimentation with steeper gradients. This facies is in turn overlain by braid bar complexes of large-scale transverse to linguoid dunes consisting of coarse-grained pebbly sandstones with conglomerate lenses. These bar complexes are compared with environments of the Recent Platte River. They represent a middle to lower alluvial plain facies with moderate gradients and no significant suspended load sedimentation or vegetation to stabilize channels. These bar complexes interfinger basinward with plane bedded medium to coarse-grained sandstones interpreted as sheet flood deposits over the distal portions of an alluvial plain with low gradients and lacking fine-grained detritus or vegetation.

Feasibility studies of in-situ coal gasification in the Warrior coal field. Quarterly report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douglas, G.W.; McKinley, M.D.

1979-03-01

Laboratory studies on a research combustor were used in an attempt to determine the length of oxidation and reduction zones. Unfortunately the buoyant effects of the heated gases caused the burn to proceed along the upper portion of the horizontal combustor. This made the interpretation of uncertain value. Methods of measuring the thermal conductivity and chemical reactivity of coke are discussed. A bibliography of the physical and chemical properties of coke is appended. (LTN)

Paleogeography of the upper Paleozoic basins of southern South America: An overview

NASA Astrophysics Data System (ADS)

Limarino, Carlos O.; Spalletti, Luis A.

2006-12-01

The paleogeographic evolution of Late Paleozoic basins located in southern South America is addressed. Three major types of basins are recognized: infracratonic or intraplate, arc-related, and retroarc. Intraplate basins (i.e., Paraná, Chaco-Paraná, Sauce Grande-Colorado, and La Golondrina) are floored by continental or quasi-continental crust, with low or moderate subsidence rates and limited magmatic and tectonic activity. Arc-related basins (northern and central Chile, Navidad-Arizaro, Río Blanco, and Calingasta-Uspallata basins and depocenters along Chilean Patagonia) show a very complex tectonic history, widespread magmatic activity, high subsidence rates, and in some cases metamorphism of Late Paleozoic sediments. An intermediate situation corresponds to the retroarc basins (eastern Madre de Dios, Tarija, Paganzo, and Tepuel-Genoa), which lack extensive magmatism and metamorphism but in which coeval tectonism and sedimentation rates were likely more important than those in the intraplate region. According to the stratigraphic distribution of Late Paleozoic sediments, regional-scale discontinuities, and sedimentation pattern changes, five major paleogeographic stages are proposed. The lowermost is restricted to the proto-Pacific and retroarc basins, corresponds to the Mississippian (stage 1), and is characterized by shallow marine and transitional siliciclastic sediments. During stage 2 (Early Pennsylvanian), glacial-postglacial sequences dominated the infracratonic (or intraplate) and retroarc basins, and terrigenous shallow marine sediments prevailed in arc-related basins. Stage 3 (Late Pennsylvanian-Early Cisuralian) shows the maximum extension of glacial-postglacial sediments in the Paraná and Sauce Grande-Colorado basins (intraplate region), whereas fluvial deposits interfingering with thin intervals of shallow marine sediments prevailed in the retroarc basins. To the west, arc-related basins were dominated by coastal to deep marine conditions (including turbiditic successions). In the Late Cisuralian (stage 4), important differences in sedimentation patterns are registered for the western arc-related basins and eastern intraplate basins. The former were locally dominated by volcaniclastic sediments or marine deposits, and the intraplate basins are characterized by shallow marine conditions punctuated by several episodes of deltaic progradation. Finally, in the Late Permian (stage 5), volcanism and volcaniclastic sedimentation dominated in basins located along the western South American margin. The intraplate basins in turn were characterized by T-R cycles composed of shallow marine, deltaic, and fluvial siliciclastic deposits.

Tectonics of Antarctica

USGS Publications Warehouse

Hamilton, W.

1967-01-01

Antarctica consists of large and wholly continental east Antarctica and smaller west Antarctica which would form large and small islands, even after isostatic rebound, if its ice cap were melted. Most of east Antarctica is a Precambrian Shield, in much of which charnockites are characteristic. The high Transantarctic Mountains, along the Ross and Weddell Seas, largely follow a geosyncline of Upper Precambrian sedimentary rocks that were deformed, metamorphosed and intruded by granitic rocks during Late Cambrian or Early Ordovician time. The rocks of the orogen were peneplained, then covered by thin and mostly continental Devonian-Jurassic sediments, which were intruded by Jurassic diabase sheets and overlain by plateau-forming tholeiites. Late Cenozoic doming and block-faulting have raised the present high mountains. Northeastern Victoria Land, the end of the Transantarctic Mountains south of New Zealand, preserves part of a Middle Paleozoic orogen. Clastic strata laid unconformably upon the Lower Paleozoic plutonic complex were metamorphosed at low grade, highly deformed and intruded by Late Devonian or Early Carboniferous granodiorites. The overlying Triassic continental sedimentary rocks have been broadly folded and normal-faulted. Interior west Antarctica is composed of miogeosynclinal clastic and subordinate carbonate rocks which span the Paleozoic Era and which were deformed, metamorphosed at generally low grade, and intruded by granitic rocks during Early Mesozoic time and possibly during other times also. Patterns of orogenic belts, if systematic, cannot yet be defined; but fragmentation and rotation of crustal blocks by oroclinal folding and strike-slip faulting can be suggested. The Ellsworth Mountains, for example, consist of Cambrian-Permian metasedimentary rocks that strike northward toward the noncorrelative and latitudinally striking Mesozoic terrane of the Antarctic Peninsula in one direction and southward toward that of the Lower Paleozoic: terrane of the Transantarctic Mountains in the other; the three regions may be separated by great strike-slip faults. The Antarctic Peninsula in west Antarctica, south of South America, consists of metavolcanic and metasedimentary rocks intruded by Late Cretaceous quartz diorite. The pre-granitic rocks are of Jurassic and Early Cretaceous ages wherever they have been dated by fossils, although some crystalline complexes may be older. The S-shape of the peninsula may represent oroclinal bending within Cenozoic time as part of a motion system in which a narrow continental bridge between South America and Antarctica was deformed and ruptured. Perhaps this bridge lagged behind as the larger continental plates drifted into the Pacific Ocean Basin. ?? 1967.

Geological constraints on continental arc activity since 720 Ma: implications for the link between long-term climate variability and episodicity of continental arcs

NASA Astrophysics Data System (ADS)

Cao, W.; Lee, C. T.

2016-12-01

Continental arc volcanoes have been suggested to release more CO2 than island arc volcanoes due to decarbonation of wallrock carbonates in the continental upper plate through which the magmas traverse (Lee et al., 2013). Continental arcs may thus play an important role in long-term climate. To test this hypothesis, we compiled geological maps to reconstruct the surface distribution of granitoid plutons and the lengths of ancient continental arcs. These results were then compiled into a GIS framework and incorporated into GPlates plate reconstructions. Our results show an episodic nature of global continental arc activity since 720 Ma. The lengths of continental arcs were at minimums during most of the Cryogenian ( 720-670 Ma), the middle Paleozoic ( 460-300 Ma) and the Cenozoic ( 50-0 Ma). Arc lengths were highest during the Ediacaran ( 640-570 Ma), the early Paleozoic ( 550-430 Ma) and the entire Mesozoic with peaks in the Early Triassic ( 250-240 Ma), Late Jurassic-Early Cretaceous ( 160-130 Ma), and Late Cretaceous ( 90-65 Ma). The extensive continental arcs in the Ediacaran and early Paleozoic reflect the Pan-African events and circum-Gondwana subduction during the assembly of the Gondwana supercontinent. The Early Triassic peak is coincident with the final closure of the paleo-Asian oceans and the onset of circum-Pacific subduction associated with the assembly of the Pangea supercontinent. The Jurassic-Cretaceous peaks reflect the extensive continental arcs established in the western Pacific, North and South American Cordillera, coincident with the initial dispersal of the Pangea. Continental arcs are favored during the final assembly and the early-stage dispersal of a supercontinent. Our compilation shows a temporal match between continental arc activity and long-term climate at least since 720 Ma. For example, continental arc activity was reduced during the Cryogenian icehouse event, and enhanced during the Early Paleozoic and Jurassic-Cretaceous greenhouse events. This coherence provides further evidence that continental arcs may play an important role in controlling long-term climate evolution. CO2 degassing fluxes from continental arcs should be incorporated into global, long-term climate models. Our work provides a quantitative framework for estimating these fluxes.

Stratigraphy of the Upper Cretaceous Mancos Shale (upper part) and Mesaverde Group in the southern part of the Uinta and Piceance basins, Utah and Colorado

USGS Publications Warehouse

Hettinger, R.D.; Kirschbaum, M.A.

2002-01-01

Cross section A–A' was constructed in support of the oil and gas assessments of the Mesaverde and Mancos/Mowry Total Petroleum Systems in the Uinta and Piceance Basins of Utah and Colorado (fig. 1) (U.S. Geological Survey Uinta-Piceance Province Assessment Team, in press). This citation is referred to henceforth as simply “USGS, in press.” The Mesaverde Total Petroleum System contains continuous gas derived primarily from carbonaceous shale and coal in the Mesaverde Group [chapter by Johnson and Roberts in USGS (in press)]. The Mancos/Mowry Total Petroleum System contains continuous gas derived primarily from marine source rocks in the Mancos and Mowry Shales [chapter by Kirschbaum in USGS (in press)]. Cross section A–A' illustrates the stratigraphy of these Upper Cretaceous rocks, emphasizing the fluvial, coal-bearing coastal plain, nearshore marine, and offshore marine strata. The cross section is presented as a hard copy in this report and as a chapter by Hettinger and Kirschbaum (USGS, in press).

Rockburst of parameters causing mining disasters in Mines of Upper Silesian Coal Basin

NASA Astrophysics Data System (ADS)

Patyńska, Renata; Mirek, Adam; Burtan, Zbigniew; Pilecka, Elżbieta

2018-04-01

In the years 2001-2015, 42 rockbursts were recorded in Polish coal mines. For the past 15 years the scale of the phenomena has been similar and ranges from 1 to 5 rockbursts per year. However, the number of recorded high energy seismic tremors of 108 and 109J (E) energy that has occurred in recent years, 2 to 5, is alarming. According to the data, 27 of tremors of E > 108 J energy that occurred between 2001 and 2015 caused 3 rockbursts. Confronting these data with seismic activity from 1989-2000, it should be noted that only 2 events out of 99 rockbursts caused tremors with energies of E>108 J. Against the background of the scale of seismic and rockburst hazards, the geological and mining conditions of the Upper Silesian Coal Basin (USCB) have been analysed, detailing the structural units in which the rockbursts occurred. On this basis, the author characterised factors that impacts on the mining excavations resulting in rockbursts that caused damage on a larger scale. These rockbursts had the characteristics of mining catastrophes and weak earthquakes not recorded in mining statistics of natural hazards of USCB so far.

Changing patterns of Pennsylvanian coal-swamp vegetation and implications of climatic control on coal occurrence

USGS Publications Warehouse

Phillips, T.L.; Peppers, R.A.

1984-01-01

Improved regional and interregional stratigraphic correlations of Pennsylvanian strata permit comparisons of vegetational changes in Euramerican coal swamps. The coal-swamp vegetation is known directly from in situ coal-ball peat deposits from more than 65 coals in the United States and Europe. Interpretations of coal-swamp floras on the basis of coal-ball peat studies are extended to broader regional and stratigraphic patterns by use of coal palynology. Objectives of the quantitative analyses of the vegetation in relation to coal are to determine the botanical constituents at the peat stage and their environmental implications for plant growth and peat accumulation. Morphological and paleoecological analyses provide a basis for deducing freshwater regimes of coal swamps. Changes in composition of Pennsylvanian coal-swamp vegetation are quire similar from one paralic coal region to another and show synchrony that is attributable to climate. Paleobotany and paleogeography of the Euramerican province indicate a moist tropical paleoclimate. Rainfall, runoff and evapotranspiration were the variable climatic controls in the distribution of coal-swamp vegetation, peat accumulation and coal resources. In relative terms of climatic wetness the Pennsylvanian Period is divisible into five intervals, which include two relatively drier intervals that developed during the Lower-Middle and Middle-Upper Pennsylvanian transitions. The climate during Early Pennsylvanian time was moderately wet and the median in moisture availability. Early Middle Pennsylvanian was drier, probably seasonally dry-wet; late Middle Pennsylvanian was the wettest in the Midcontinent; early Late Pennsylvanian was the driest; and late Late Pennsylvanian was probably the wettest in the Dunkard Basin. The five climatic intervals represent a general means of dividing coal resources within each region into groups with similar botanical constituents and environments of peat accumulation. Regional differences in basinal geology and climate were significant variables, but the synchronous control of paleoclimate was of primary importance. ?? 1984.

Sulfur variability and petrology of the Lower Block Coal Member (Pennsylvanian) in Southwest Indiana

USGS Publications Warehouse

Padgett, P.L.; Rimmer, S.M.; Ferm, J.C.; Hower, J.C.; Eble, C.F.; Mastalerz, Maria

1999-01-01

The Lower Block Coal Member (Pennsylvanian-Atokan, Westphalian C) is an economic low-to medium-sulfur, low-ash coal resource in the Illinois Basin. Sulfur content is generally low (averaging 1.0%) in the study area, but varies over short distances. Higher sulfur areas occur as isolated pods and epigenetic pyrite increases significantly in the upper third of the selected columns in higher sulfur areas. Sulfur variations cannot be predicted by typical geologic characteristics such as roof lithology, seam thickness, or seam elevation. Petrographic analysis shows that pyrite is generally associated with brighter microlithotypes, except in higher sulfur areas where infilling pyrite forms are associated with inertite. Higher sulfur areas reflect the water chemistry of the paleomire during and shortly after peat accumulation. Locally, abundant pyrofusinite provided additional pore space for pyrite precipitation.The Lower Block Coal Member (Pennsylvanian-Atokan, Westphalian C) is an economic low- to medium-sulfur, low-ash coal resource in the Illinois Basin. Sulfur content is generally low (averaging 1.0%) in the study area, but varies over short distances. Higher sulfur areas occur as isolated pods and epigenetic pyrite increases significantly in the upper third of the selected columns in higher sulfur areas. Sulfur variations cannot be predicted by typical geologic characteristics such as roof lithology, seam thickness, or seam elevation. Petrographic analysis shows that pyrite is generally associated with brighter microlithotypes, except in higher sulfur areas where infilling pyrite forms are associated with inertite. Higher sulfur areas reflect the water chemistry of the paleomire during and shortly after peat accumulation. Locally, abundant pyrofusinite provided additional pore space for pyrite precipitation.

PROTON MICROPROBE ANALYSIS OF TRACE-ELEMENT VARIATIONS IN VITRINITES IN THE SAME AND DIFFERENT COAL BEDS.

USGS Publications Warehouse

Minkin, J.A.; Chao, E.C.T.; Blank, Herma; Dulong, F.T.

1987-01-01

The PIXE (proton-induced X-ray emission) microprobe can be used for nondestructive, in-situ analyses of areas as small as those analyzed by the electron microprobe, and has a sensitivity of detection as much as two orders of magnitude better than the electron microprobe. Preliminary studies demonstrated that PIXE provides a capability for quantitative determination of elemental concentrations in individual coal maceral grains with a detection limit of 1-10 ppm for most elements analyzed. Encouraged by the earlier results, we carried out the analyses reported below to examine trace element variations laterally (over a km range) as well as vertically (cm to m) in the I and J coal beds in the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale in central Utah, and to compare the data with the data from two samples of eastern coals of Pennsylvanian age.

Assessment of the suitability of trees for brownfields reuse in the post-mining landscape

NASA Astrophysics Data System (ADS)

Mec, J.; Lokajickova, B.; Sotkova, N.; Svehlakova, H.; Stalmachova, B.

2017-10-01

The post-mining landscape of Upper Silesian is deterioration of the original landscape caused by underground coal mining. There are huge ecosystems changes, which have been reclaimed by nature-friendly procedures. The aim of the work is to evaluate the suitability of selected trees for reuse of brownfields in this landscape and proposals for reclamation in the interest areas of Upper Silesian.

Characterization of coal-derived hydrocarbons and source-rock potential of coal beds, San Juan Basin, New Mexico and Colorado, U.S.A.

USGS Publications Warehouse

Rice, D.D.; Clayton, J.L.; Pawlewicz, M.J.

1989-01-01

Coal beds are considered to be a major source of nonassociated gas in the Rocky Mountain basins of the United States. In the San Juan basin of northwestern New Mexico and southwestern Colorado, significant quantities of natural gas are being produced from coal beds of the Upper Cretaceous Fruitland Formation and from adjacent sandstone reservoirs. Analysis of gas samples from the various gas-producing intervals provided a means of determining their origin and of evaluating coal beds as source rocks. The rank of coal beds in the Fruitland Formation in the central part of the San Juan basin, where major gas production occurs, increases to the northeast and ranges from high-volatile B bituminous coal to medium-volatile bituminous coal (Rm values range from 0.70 to 1.45%). On the basis of chemical, isotopic and coal-rank data, the gases are interpreted to be thermogenic. Gases from the coal beds show little isotopic variation (??13C1 values range -43.6 to -40.5 ppt), are chemically dry (C1/C1-5 values are > 0.99), and contain significant amounts of CO2 (as much as 6%). These gases are interpreted to have resulted from devolatilization of the humic-type bituminous coal that is composed mainly of vitrinite. The primary products of this process are CH4, CO2 and H2O. The coal-generated, methane-rich gas is usually contained in the coal beds of the Fruitland Formation, and has not been expelled and has not migrated into the adjacent sandstone reservoirs. In addition, the coal-bed reservoirs produce a distinctive bicarbonate-type connate water and have higher reservoir pressures than adjacent sandstones. The combination of these factors indicates that coal beds are a closed reservoir system created by the gases, waters, and associated pressures in the micropore coal structure. In contrast, gases produced from overlying sandstones in the Fruitland Formation and underlying Pictured Cliffs Sandstone have a wider range of isotopic values (??13C1 values range from -43.5 to -38.5 ppt), are chemically wetter (C1/C1-5 values range from 0.85 to 0.95), and contain less CO2 (< 2%). These gases are interpreted to have been derived from type III kerogen dispersed in marine shales of the underlying Lewis Shale and nonmarine shales of the Fruitland Formation. In the underlying Upper Cretaceous Dakota Sandstone and Tocito Sandstone Lentil of the Mancos Shale, another gas type is produced. This gas is associated with oil at intermediate stages of thermal maturity and is isotopically lighter and chemically wetter at the intermediate stage of thermal maturity as compared with gases derived from dispersed type III kerogen and coal; this gas type is interpreted to have been generated from type II kerogen. Organic matter contained in coal beds and carbonaceous shales of the Fruitland Formation has hydrogen indexes from Rock-Eval pyrolysis between 100 and 350, and atomic H:C ratios between 0.8 and 1.2. Oxygen indexes and atomic O:C values are less than 24 and 0.3, respectively. Extractable hydrocarbon yields are as high as 7,000 ppm. These values indicate that the coal beds and carbonaceous shales have good potential for the generation of liquid hydrocarbons. Voids in the coal filled with a fluorescent material that is probably bitumen is evidence that liquid hydrocarbon generation has taken place. Preliminary oil-source rock correlations based on gas chromatography and stable carbon isotope ratios of C15+ hydrocarbons indicate that the coals and (or) carbonaceous shales in the Fruitland Formation may be the source of minor amounts of condensate produced from the coal beds at relatively low levelsof thermal maturity (Rm=0.7). ?? 1989.

Effects of detrital influx in the Pennsylvanian Upper Freeport peat swamp

USGS Publications Warehouse

Ruppert, L.F.; Stanton, R.W.; Blaine, Cecil C.; Eble, C.F.; Dulong, F.T.

1991-01-01

Quartz cathodoluminescence properties and mineralogy of three sets of samples and vegetal and/ or miospore data from two sets of samples from the Upper Freeport coal bed, west-central Pennsylvania, show that detrital influence from a penecontemporaneous channel is limited to an area less than three km from the channel. The sets of samples examined include localities of the coal bed where (1) the coal is thin, split by partings, and near a penecontemporaneous fluvial channel, (2) the coal is relatively thick and located approximately three km from the channel, and (3) the coal is thick and located approximately 12 km from the channel. Samples from locality 1 (nearest the channel) have relatively high-ash yields (low-temperature ash average = 27.3% on a pyrite- and calcite-free basis) and high proportions of quartz and clay minerals. The quartz is primarily detrital, as determined by cathodoluminescent properties, and the ratio of kaolinite to illite is low. In addition, most of the plant remains and miospores indicate peat-forming plants that required low nutrient levels for growth. In contrast, samples from localities 2 and 3, from the more interior parts of the bed, contained predominantly authigenic quartz grains nd yielded low-temperature ash values of less than 14% on a pyrite- and calcite-free basis. The low-temperature ash contains low concentrations of quartz and clay minerals and the ratio of kaolinite to illite is relatively high. Although intact core was not available for paleobotanical analyses, another core collected within 1 km from locality 3 contained plant types interpreted to have required high nutrient levels for growth. These data indicate that mineral formation is dominated by authigenic processes in interior parts of the coal body. Some of the authigenic quartz may have been derived from herbaceous ferns as indicated by patterns in the palynological and paleobotanical data. In contrast, detrital processes appeared to be limited to in areas directly adjacent to the penecontemporaneous channel where the coal bed is high in ash, split by mineral-rich partings, and of little or no economic value. ?? 1991.

Relationships among macerals, minerals, miospores and paleoecology in a column of Redstone coal (Upper Pennsylvanian) from north-central West Virginia (U.S.A.)

USGS Publications Warehouse

Grady, W.C.; Eble, C.F.

1990-01-01

Two distinct paleoenvironments are represented in vertical succession in a column of Redstone coal in north-central West Virginia as indicated by a study of 37 consecutive 3-cm (0.1 ft) increments analyzed for ash yield, petrographic composition, low-temperature ash mineralogy and palynomorph abundances. Abundance profiles were constructed for ash, 12 petrographic components, 3 minerals and 5 miospore assemblages. The profiles and calculated correlation coefficients show close relationships between several constituents. Components that increased in abundance upward in the coal bed were a collinite type > 50 microns in thickness, cutinite, and miospores affiliated with calamites, herbaceous lycopods, cordaites and herbaceous ferns. Components that decreased in abundance upward were a collinite type 50 ??m in thickness, cutinite, calamite and cordaite miospores and kaolinite. Significant correlations occurred between ash yield and the collinite types > 50 and < 50 ??m in thickness but no significant correlation was found between ash yield and total vitrinite-group content. This is interpreted to show that division of vitrinite macerals by size is important in petrographic paleoenvironmental studies. Paleoecologic interpretations based upon these correlations suggest that two distinct, planar, probably topogenous paleoecologic environments are represented in this column of the Redstone coal. The lower two-thirds of the coal bed was interpreted to have accumulated in a planar swamp in which significant introduction of detrital or dissolved mineral matter, and significant anaerobic and moderate oxidative degradation of the peat occurred. The flora of this paleoenvironment was dominated by tree ferns. The paleoenvironment during accumulation of the upper one-third of the coal bed was also interpreted to have been a planar swamp, but one in which moderate to low introduction of detrital or dissolved mineral matter, and minor anaerobic and oxidative degradation of the peat occurred. The dominant flora of this paleoenvironment consisted mainly of calamites with fewer cordaites and herbaceous ferns. This study shows that valuable paleoecologic information may be obtained by sampling closely spaced vertical increments. No mixing of detrital sediments with the peat was observed in coal layers immediately adjacent to the parting or the overlying sandstone unit. ?? 1990.

Quantitative Modelling of Trace Elements in Hard Coal.

PubMed

Smoliński, Adam; Howaniec, Natalia

2016-01-01

The significance of coal in the world economy remains unquestionable for decades. It is also expected to be the dominant fossil fuel in the foreseeable future. The increased awareness of sustainable development reflected in the relevant regulations implies, however, the need for the development and implementation of clean coal technologies on the one hand, and adequate analytical tools on the other. The paper presents the application of the quantitative Partial Least Squares method in modeling the concentrations of trace elements (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Rb, Sr, V and Zn) in hard coal based on the physical and chemical parameters of coal, and coal ash components. The study was focused on trace elements potentially hazardous to the environment when emitted from coal processing systems. The studied data included 24 parameters determined for 132 coal samples provided by 17 coal mines of the Upper Silesian Coal Basin, Poland. Since the data set contained outliers, the construction of robust Partial Least Squares models for contaminated data set and the correct identification of outlying objects based on the robust scales were required. These enabled the development of the correct Partial Least Squares models, characterized by good fit and prediction abilities. The root mean square error was below 10% for all except for one the final Partial Least Squares models constructed, and the prediction error (root mean square error of cross-validation) exceeded 10% only for three models constructed. The study is of both cognitive and applicative importance. It presents the unique application of the chemometric methods of data exploration in modeling the content of trace elements in coal. In this way it contributes to the development of useful tools of coal quality assessment.

Mineralogical Studies Related to Endemic Diseases in Rural P. R. China

NASA Astrophysics Data System (ADS)

Belkin, H. E.; Zheng, B.; Finkelman, R. B.

2003-12-01

Domestic combustion of coal for heating and cooking is mostly confined to the world's developing countries and probably involves about 1 billion persons in China, India, Indonesia, and Africa. Various endemic diseases affecting millions of people involving arsenic, selenium, and fluorine poisoning have been associated with domestic coal combustion in rural China. We have investigated the relationship between mineralized coals (and stone coals) and disease occurrences in Guizhou and Hubei Provinces. The mineralogy of the coals has been studied by a wide variety of techniques, including optical petrography, scanning electron microscopy, electron microprobe analysis, ion probe, Synchrotron XANES-EXAFS, and Raman spectroscopy. Arsenic enrichment (up to 3 weight percent) in Upper Permian Longtan Formation coals, southwestern Guizhou Province, occurs in both 3+ and 5+ valence states. Arsenic occurs in arsenopyrite, pyrite, Al-phosphate, scorodite, Fe-oxides, and as an organically-bound species. Fluorine poisoning, much more widespread than arsenic-poisoning, is related to burning F-rich coals and F-rich clays as admixtures. Mineralogical and chemical analysis suggests that the clays contain the fluorine probably substituting for the hydroxyl group. Localized selenium poisoning in Hubei Province is related to Se-rich stone coals. The selenium occurs as a native element and in rare mandarinoite. In these three cases, knowledge of the paragenesis and mineralogy of the element enrichment in coal was vital to help understand and mitigate the endemic diseases. For the situation concerning arsenic and selenium poisoning, suspect coals have been identified and mining from these deposits has been curtailed. Fluorine has been a much more difficult problem for the local public health officials as both the coal and clay in the burning admixture can contain high fluorine. Regional geochemical and mineralogical studies will help to define coal and clay with low fluorine, suitable for domestic use.

Quantitative Modelling of Trace Elements in Hard Coal

PubMed Central

Smoliński, Adam; Howaniec, Natalia

2016-01-01

The significance of coal in the world economy remains unquestionable for decades. It is also expected to be the dominant fossil fuel in the foreseeable future. The increased awareness of sustainable development reflected in the relevant regulations implies, however, the need for the development and implementation of clean coal technologies on the one hand, and adequate analytical tools on the other. The paper presents the application of the quantitative Partial Least Squares method in modeling the concentrations of trace elements (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Rb, Sr, V and Zn) in hard coal based on the physical and chemical parameters of coal, and coal ash components. The study was focused on trace elements potentially hazardous to the environment when emitted from coal processing systems. The studied data included 24 parameters determined for 132 coal samples provided by 17 coal mines of the Upper Silesian Coal Basin, Poland. Since the data set contained outliers, the construction of robust Partial Least Squares models for contaminated data set and the correct identification of outlying objects based on the robust scales were required. These enabled the development of the correct Partial Least Squares models, characterized by good fit and prediction abilities. The root mean square error was below 10% for all except for one the final Partial Least Squares models constructed, and the prediction error (root mean square error of cross–validation) exceeded 10% only for three models constructed. The study is of both cognitive and applicative importance. It presents the unique application of the chemometric methods of data exploration in modeling the content of trace elements in coal. In this way it contributes to the development of useful tools of coal quality assessment. PMID:27438794

The Myszkow porphyry copper-molybdenum deposit, Poland

USGS Publications Warehouse

Chaffee, M.A.; Eppinger, R.G.; Lason, K.; Slosarz, J.; Podemski, M.

1994-01-01

The porphyry copper-molybdenum deposit at Myszkow, south-central Poland, lies in the Cracow-Silesian orogenic belt, in the vicinity of a Paleozoic boundary between two tectonic plates. The deposit is hosted in a complex that includes early Paleozoic metasedimentary rocks intruded in the late Paleozoic by a predominantly granodioritic pluton. This deposit exhibits many features that are typical of porphyry copper deposits associated with calc-alkaline intrusive rocks, including ore- and alteration-mineral suites, zoning of ore and alteration minerals, fluid-inclusion chemistry, tectonic setting, and structural style of veining. Unusual features of the Myszkow deposit include high concentrations of tungsten and the late Paleozoic (Variscan) age. -Authors

An exhumed Late Paleozoic canyon in the rocky mountains

USGS Publications Warehouse

Soreghan, G.S.; Sweet, D.E.; Marra, K.R.; Eble, C.F.; Soreghan, M.J.; Elmore, R.D.; Kaplan, S.A.; Blum, M.D.

2007-01-01

Landscapes are thought to be youthful, particularly those of active orogenic belts. Unaweep Canyon in the Colorado Rocky Mountains, a large gorge drained by two opposite-flowing creeks, is an exception. Its origin has long been enigmatic, but new data indicate that it is an exhumed late Paleozoic landform. Its survival within a region of profound late Paleozoic orogenesis demands a reassessment of tectonic models for the Ancestral Rocky Mountains, and its form and genesis have significant implications for understanding late Paleozoic equatorial climate. This discovery highlights the utility of paleogeomorphology as a tectonic and climatic indicator. ?? 2007 by The University of Chicago. All rights reserved.

Potential effects of surface coal mining on the hydrology of the Little Bear Creek area, Moorhead coal field, southeastern Montana

USGS Publications Warehouse

McClymonds, N.E.

1986-01-01

The Little Bear Creek area of the Moorhead Coal Field, 27 miles south of Ashland, Montana, contains large reserves of Federally owned coal that have been identified for potential lease sale. A hydrologic study was conducted in the area to describe existing hydrologic system and to assess potential effects of surface mining on local water resources. Hydrologic data collected from private wells, observation wells, test holes and springs indicate that the aquifers are coal and sandstone beds in the upper part of the Tongue River Member, Fort Union Formation (Paleocene age), and sand and gravel layers of valley alluvium (Pleistocene and Holocene age). Surface water is available from ephemeral flow along stretches of the main streams, and from stock ponds throughout the area. Mining the Anderson and Dietz coal beds would destroy one stock well and several stock ponds, would possibly interfere with the flow of one spring, and would lower the potentiometric surface within the coal and sandstone aquifers. The alluvial aquifer beneath Little Bear Creek and Davidson Draw would be removed at the mine site, as would sandstone and coal aquifers above the mine floor. Although mining would alter existing hydrologic systems, alternative water supplies are available. Planned structuring of the spoils and reconstruction of the alluvial aquifers could minimize downstream water-quality degradation. (USGS)

Paleozoic-Mesozoic boundary in the Berry Creek Quadrangle, northwestern Sierra Nevada, California

USGS Publications Warehouse

Hietanen, Anna Martta

1977-01-01

Structural and petrologic studies in the Berry Creek quadrangle at the north end of the western metamorphic belt of the Sierra Nevada have yielded new information that helps in distinguishing between the chemically similar Paleozoic and Mesozoic rocks. The distinguishing features are structural and textural and result from different degrees of deformation. Most Paleozoic rocks are strongly deformed and thoroughly recrystallized. Phenocrysts in meta volcanic rocks are granulated and drawn out into lenses that have sutured outlines. In contrast, the phenocrysts in the Mesozoic metavolcanic rocks show well-preserved straight crystal faces, are only slightly or not at all granulated, and contain fewer mineral inclusions than do those in the Paleozoic rocks. The groundmass in the Paleozoic rocks is recrystallized to a fairly coarse grained albite-epidote-amphibole-chlorite rock, whereas in the Mesozoic rocks the groundmass is a very fine grained feltlike mesh with only spotty occurrence of well-recrystallized finegrained albite-epidote-chlorite-actinolite rock. Primary minerals, such as augite, are locally preserved in the Mesozoic rocks but are altered to a mixture of amphibole, chlorite, and epidote in the Paleozoic rocks. In the contact aureoles of the plutons, and within the Big Bend fault zone, which crosses the area parallel to the structural trends, all rocks are thoroughly recrystallized and strongly deformed. Identification of the Paleozoic and Mesozoic rocks in these parts of the area was based on the continuity of the rock units in the field and on gradual changes in microscopic textures toward the plutons.

Crew Earth Observations (CEO) taken during Expedition Six

NASA Image and Video Library

2003-02-01

ISS006-E-28028 (February 2003) --- The Southern Cross (left center), the Coal Sack Nebula (bottom left), and the Carina Nebula (upper right) are visible in this view photographed by astronaut Donald R. Pettit, Expedition Six NASA ISS science officer, on board the International Space Station (ISS). The Carina Nebula is a molecular cloud about 9000 light years from Earth where young stars are forming. The Coal Sack Nebula is an inky-black dust cloud about 2000 light years from Earth. Stars are probably condensing deep inside the Coal Sack, but their light has not yet broken through the cloud’s dense exterior. The Southern Cross, also known as The Crux, is a constellation familiar to southern hemisphere stargazers.

Long-term effects of surface coal mining on ground-water levels and quality in two small watersheds in eastern Ohio

USGS Publications Warehouse

Cunningham, W.L.; Jones, R.L.

1990-01-01

Two small watersheds in eastern Ohio that were surface mined for coal and reclaimed were studied during 1986-89. Water-level and water-quality data were compared with similar data collected during previous investigations conducted during 1976-83 to determine long-term effects of surface mining on the hydrologic system. Before mining, the watersheds were characterized by sequences of flat-lying sedimentary rocks containing two major coal seams and underclays. An aquifer was present above each of the underclays. Surface mining removed the upper aquifer, stripped the coal seam, and replaced the sediment. This created a new upper aquifer with different hydraulic and chemical characteristics. Mining did not disturb the middle aquifer. A third, deeper aquifer in each watershed was not studied. Water levels were continuously recorded in one well in each aquifer. Other wells were measured every 2 months. Water levels in the upper aquifers reached hydraulic equilibrium from 2 to 5 years after mining ceased. Water levels in the middle aquifers increased more than 5 feet during mining and reached equilibrium almost immediately thereafter. Water samples were collected from three upper-aquifer well, a seep from the upper aquifer, and the stream in each watershed. Two samples were collected in 1986 and 1987, and one each in 1988 and 1989. In both watersheds, sulfate replaced bicarbonate as the dominant upper-aquifer and surface-water anion after mining. For the upper aquifer of a watershed located in Muskingum County, water-quality data were grouped into premining and late postmining time periods (1986-89). The premining median pH and concentration of dissolved solids and sulfate were 7.6, 378 mg/L (milligrams per liter), and 41 mg/L, respectively. The premining median concentrations of iron and manganese were 10? /L (micrograms per liter) and 25?, respectively. The postmining median values of pH, dissolved solids, and sulfate were 6.7, 1,150 mg/L, and 560 mg/L, respectively. The postmining median concentrations of iron and manganese were 3,900?g/L and 1,900? g/L, respectively. For the upper aquifer of a watershed located in Jefferson County, the water-quality data were grouped into three time periods of premining, early postmining, and late postmining. The premining median pH and concentrations of dissolved solids and sulfate were 7.0, 335 mg/L, and 85 mg/L, respectively. The premining median concentrations of iron and manganese were 30? g/L for each constituent. Late postmining median pH and concentrations of dissolved solids and sulfate were 6.7, 1,495 mg/L, and 825 mg/L, respectively. The postmining median concentrations of iron and manganese were 31? g/L and 1,015? g/L, respectively. Chemistry of water in the middle aquifer in each watershed underwent similar changes. In general, statistically significant increases in concentrations of dissolved constituents occurred because of surface mining. In some constituents, concentrations increased by more than an order of magnitude. The continued decrease in pH indicated that ground water had no reached geochemical equilibrium in either watershed more than 8 years after mining.

6. VIEW NORTHWEST OF SOUTHEAST FACADE AND STACK BASE; LOCKER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW NORTHWEST OF SOUTHEAST FACADE AND STACK BASE; LOCKER ROOM AT LEFT, COAL CONVEYOR REMAINS AT UPPER RIGHT - Turners Falls Power & Electric Company, Hampden Station, East bank of Connecticut River, Chicopee, Hampden County, MA

Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event

PubMed Central

Schiffbauer, James D.; Huntley, John Warren; Fike, David A.; Jeffrey, Matthew Jarrell; Gregg, Jay M.; Shelton, Kevin L.

2017-01-01

Several positive carbon isotope excursions in Lower Paleozoic rocks, including the prominent Upper Cambrian Steptoean Positive Carbon Isotope Excursion (SPICE), are thought to reflect intermittent perturbations in the hydrosphere-biosphere system. Models explaining these secular changes are abundant, but the synchronicity and regional variation of the isotope signals are not well understood. Examination of cores across a paleodepth gradient in the Upper Cambrian central Missouri intrashelf basin (United States) reveals a time-transgressive, facies-dependent nature of the SPICE. Although the SPICE event may be a global signal, the manner in which it is recorded in rocks should and does vary as a function of facies and carbonate platform geometry. We call for a paradigm shift to better constrain facies, stratigraphic, and biostratigraphic architecture and to apply these observations to the variability in magnitude, stratigraphic extent, and timing of the SPICE signal, as well as other biogeochemical perturbations, to elucidate the complex processes driving the ocean-carbonate system. PMID:28275734

Patrick Draw field, Wyoming - 1 seismic expression of subtle strat trap in Upper Cretaceous Almond

USGS Publications Warehouse

Ryder, Robert T.; Lee, Myung W.; Agena, Warren F.; Anderson, Robert C.

1990-01-01

The east flank of the Rock Springs uplift and the adjacent Wamsutter arch contain several large hydrocarbon accumulations. Among these accumulations are Patrick Draw field, which produces oil and gas from a stratigraphic trap in the Upper Cretaceous Almond formation, and Table Rock field, a faulted anticlinal trap that produces gas from multiple Tertiary, Mesozoic, and Paleozoic reservoirs. The principal petroleum reservoir in Patrick Draw field is a sandstone at the top of the Almond formation. This sandstone attains a maximum thickness of 35ft and piches out westward into relatively impervious silt-stone and shale that constitute the trapping facies. The objective of this investigation is to determine whether or not the stratigraphic trap at Patrick Draw can be detected on a 12 fold, common depth point seismic profile acquired by Forest Oil Corp. and its partners. The seismic line is 18.5 miles long and crosses Patrick Draw and Table Rock fields.

Completely preserved cockroaches of the family Mesoblattinidae from the Upper Jurassic-Lower Cretaceous Yixian Formation (Liaoning Province, NE China)

NASA Astrophysics Data System (ADS)

Wei, Dandan; Ren, Dong

2013-08-01

Although cockroaches were the dominant insects in various Paleozoic and Mesozoic insect assemblages, their general morphology was extremely conservative. One of the most common of them, the Jurassic-Cretaceous family Mesoblattinidae, is described here for the first time on the basis of completely preserved specimens. Ninety-two specimens of Perlucipecta aurea gen. et sp. n. reveal details of head, mandible, male tergal glands and terminal hook; cercal, leg and antennal sensilla. Its congener, P. vrsanskyi is described from the same sediments of the Yixian Formation (Upper Jurassic-Lower Cretaceous). The forewing venation variability of P. aurea, analysed for the first time in this family is nearly identical (CV = 6.23 %) with variability of two species of family Blattulidae that occur at the same locality (CV = 6.22 %; 5.72 %). The transitional nature of morphological characters represented by asymmetry between left and right wings (simple/branched forewing SC and hind wing M) in P. aurea documents the phylogenetic relation between the families Mesoblattinidae and Ectobiidae

Petrography and geochemistry of the Middle Devonian coal from Luquan, Yunnan Province, China

USGS Publications Warehouse

Dai, S.; Han, D.; Chou, C.-L.

2006-01-01

Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 ??g/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation. ?? 2005 Elsevier Ltd. All rights reserved.

Late Devonian glacial deposits from the eastern United States signal an end of the mid-Paleozoic warm period

USGS Publications Warehouse

Brezinski, D.K.; Cecil, C.B.; Skema, V.W.; Stamm, R.

2008-01-01

A Late Devonian polymictic diamictite extends for more than 400??km from northeastern Pennsylvania across western Maryland and into east-central West Virginia. The matrix-supported, unbedded, locally sheared diamictite contains subangular to rounded clasts up to 2??m in diameter. The mostly rounded clasts are both locally derived and exotic; some exhibit striations, faceting, and polish. The diamictite commonly is overlain by laminated siltstone/mudstone facies associations (laminites). The laminites contain isolated clasts ranging in size from sand and pebbles to boulders, some of which are striated. The diamictite/laminite sequence is capped by massive, coarse-grained, pebbly sandstone that is trough cross-bedded. A stratigraphic change from red, calcic paleo-Vertisols in strata below the diamictite to non-calcic paleo-Spodosols and coal beds at and above the diamictite interval suggests that the climate became much wetter during deposition of the diamictite. The diamictite deposit is contemporaneous with regressive facies that reflect fluvial incision during the Late Devonian of the Appalachian basin. These deposits record a Late Devonian episode of climatic cooling so extreme that it produced glaciation in the Appalachian basin. Evidence for this episode of climatic cooling is preserved as the interpreted glacial deposits of diamictite, overlain by glaciolacustrine varves containing dropstones, and capped by sandstone interpreted as braided stream outwash. The Appalachian glacigenic deposits are contemporaneous with glacial deposits in South America, and suggest that Late Devonian climatic cooling was global. This period of dramatic global cooling may represent the end of the mid-Paleozoic warm interval that began in the Middle Silurian. ?? 2008 Elsevier B.V. All rights reserved.

Paleogeothermal gradients and timing of oil generation in the Belden Formation, Eagle Basin, northwestern Colorado

USGS Publications Warehouse

Nuccio, V.F.; Johnson, S.Y.; Schenk, C.J.

1989-01-01

Paleogeothermal gradients and timing of oil generation for the Lower and Middle Pennsylvanian Belden Formation have been estimated for four locations in the Eagle Basin of northwestern Colorado, by comparing measured vitrinite reflectance with maturity modeling. Two thermal models were made for each location: one assumes a constant paleogeothermal gradient through time while the other is a two-stage model with changing paleogeothermal gradients. The two-stage paleogeothermal gradient scenario is considered more geologically realistic and is used to estimate the timing of oil generation throughout the Eagle basin. From the data and interpretations, one would expect Belden oil to be found in either upper Paleozoic or Mesozoic reservoir rocks. -Authors

Low-angle faulting in strike-slip dominated settings: Seismic evidence from the Maritimes Basin, Canada

NASA Astrophysics Data System (ADS)

Pinet, Nicolas; Dietrich, Jim; Duchesne, Mathieu J.; Hinds, Steve J.; Brake, Virginia

2018-07-01

The Maritimes Basin is an upper Paleozoic sedimentary basin centered in the Gulf of St. Lawrence (Canada). Early phases of basin formation included the development of partly connected sub-basins bounded by high-angle faults, in an overall strike-slip setting. Interpretation of reprocessed seismic reflection data indicates that a low-angle detachment contributed to the formation of a highly asymmetric sub-basin. This detachment was rotated toward a lower angle and succeeded by high-angle faults that sole into the detachment or cut it. This model bears similarities to other highly extended terranes and appears to be applicable to strike-slip and/or transtensional settings.

Thick-skinned tectonics in a Late Cretaceous-Neogene intracontinental belt (High Atlas Mountains, Morocco): The flat-ramp fault control on basement shortening and cover folding

NASA Astrophysics Data System (ADS)

Fekkak, A.; Ouanaimi, H.; Michard, A.; Soulaimani, A.; Ettachfini, E. M.; Berrada, I.; El Arabi, H.; Lagnaoui, A.; Saddiqi, O.

2018-04-01

Most of the structural studies of the intracontinental High Atlas belt of Morocco have dealt with the central part of the belt, whose basement does not crop out. Here we study the Alpine deformation of the North Subatlas Zone, which is the part of the Western High Atlas (WHA) Paleozoic Massif that involves both Paleozoic basement units and remnants of their Mesozoic-Cenozoic cover formations. Our aim is to better constrain the geometry and kinematics of the basement faults during the Alpine shortening. Based on detail mapping, satellite imagery and field observations, we describe an array of sub-equatorial, transverse and oblique faults between the WHA Axial Zone and the Haouz Neogene basin. They define a mosaic of basement blocks pushed upon one another and upon the Haouz basement along the North Atlas Fault (NAF). The Axial Zone makes up the hanging-wall of the Adassil-Medinet Fault (AMF) south of this mosaic. The faults generally presents flat-ramp-flat geometry linked to the activation of multiple décollement levels, either within the basement where its foliation is subhorizontal or within favourable cover formations (Jurassic evaporites, Lower Cretaceous silty red beds, Upper Cretaceous evaporitic marls, Neogene basal argillites). The occurrence of the North Atlas detachment (NAD) allowed folded pop-up units to develop in front of the propagating NAF. Shortening began as early as the Campanian-Maastrichtian along the AMF. The direction of the maximum horizontal stress rotated from NNE-SSW to NNW-SSE from the Maastrichtian-Paleocene to the Neogene. The amount of shortening reaches 20% in the Azegour transect. This compares with the shortening amount published for the central-eastern High Atlas, suggesting that similar structures characterize the Paleozoic basement all along the belt. The WHA thick-skinned tectonics evokes that of the frontal Sevier belt and of the external Western Alps, although with a much minor pre-inversion burial.

Geochemistry of trace elements in coals from the Zhuji Mine, Huainan Coalfield, Anhui, China

USGS Publications Warehouse

Sun, R.; Liu, Gaisheng; Zheng, Lingyun; Chou, C.-L.

2010-01-01

The abundances of nine major elements and thirty-eight trace elements in 520 samples of low sulfur coals from the Zhuji Mine, Huainan Coalfield, Anhui, China, were determined. Samples were mainly collected from 10 minable coal seams of 29 boreholes during exploration. The B content in coals shows that the influence of brackish water decreased toward the top of coal seams; marine transgression and regression occurred frequently in the Lower Shihezi Formation. A wide range of elemental abundances is found. Weighted means of Na, K, Fe, P, Be, B, Co, Ni, Cr, Se, Sb, Ba, and Bi abundances in Zhuji coals are higher, and the remainder elements are either lower or equal to the average values of elements in coals of northern China. Compared to the Chinese coals, the Zhuji coals are higher in Na, K, Be, B, Cr, Co, Se, Sn, Sb, and Bi, but lower in Ti, P, Li, V and Zn. The Zhuji coals are lower only in S, P, V and Zn than average U.S. and world coals. Potassium, Mg, Ca, Mn, Sr, As, Se, Sb and light rare earth elements (LREE) had a tendency to be enriched in thicker coal seams, whereas Fe, Ti, P, V, Co, Ni, Y, Mo, Pb and heavy rare earth elements (HREE) were inclined to concentrate in thinner coal seams. The enrichment of some elements in the Shanxi or Upper Shihezi Formations is related to their depositional environments. The elements are classified into three groups based on their stratigraphic distributions from coal seams 3 to 11-2, and the characteristics of each group are discussed. Lateral distributions of selected elements are also investigated. The correlation coefficients of elemental abundances with ash content show that the elements may be classified into four groups related to modes of occurrence of these elements. ?? 2009 Elsevier B.V. All rights reserved.

Fluid inclusions and biomarkers in the Upper Mississippi Valley zinc-lead district; implications for the fluid-flow and thermal history of the Illinois Basin

USGS Publications Warehouse

Rowan, E. Lanier; Goldhaber, Martin B.

1996-01-01

The Upper Mississippi Valley zinc-lead district is hosted by Ordovician carbonate rocks at the northern margin of the Illinois Basin. Fluid inclusion temperature measurements on Early Permian sphalerite ore from the district are predominantly between 90?C and I50?C. These temperatures are greater than can be explained by their reconstructed burial depth, which was a maximum of approximately 1 km at the time of mineralization. In contrast to the temperatures of mineral formation derived from fluid inclusions, biomarker maturities in the Upper Mississippi Valley district give an estimate of total thermal exposure integrated over time. Temperatures from fluid inclusions trapped during ore genesis with biomarker maturities were combined to construct an estimate of the district's overall thermal history and, by inference, the late Paleozoic thermal and hydrologic history of the Illinois Basin. Circulation of groundwater through regional aquifers, given sufficient flow rates, can redistribute heat from deep in a sedimentary basin to its shallower margins. Evidence for regional-scale circulation of fluids is provided by paleomagnetic studies, regionally correlated zoned dolomite, fluid inclusions, and thermal maturity of organic matter. Evidence for igneous acti vity contemporaneous with mineralization in the vicinity of the Upper Mississippi Valley district is absent. Regional fluid and heat circulation is the most likely explanation for the elevated fluid inclusion temperatures (relative to maximum estimated burial depth) in the Upper Mississippi Valley district. One plausible driving mechanism and flow path for the ore-forming fluids is groundwater recharge in the late Paleozoic Appalachian-Ouachita mountain belt and northward flow through the Reelfoot rift and the proto- Illinois Basin to the Upper Mississippi Valley district. Warm fluid flowing laterally through Cambrian and Ordovician aquifers would then move vertically upward through the fractures that control sphalerite mineralization in the Upper Mississippi Valley district. Biomarker reactant-product measurements on rock extracts from the Upper Mississippi Valley district define a relatively low level ofthermal maturity for the district, 0.353 for sterane and 0.577 for hopane. Recently published kinetic constants permit a time-temperature relationship to be determined from these biomarker maturities. Numerical calculations were made to simulate fluid heat flow through the fracture-controlled ore zones of the Thompson-Temperly mine and heat transfer to the adjacent rocks where biomarker samples were collected. Calculations that combine the fluid inclusion temperatures and the biomarker constraints on thermal maturity indicate that the time interval during which mineralizing fluids circulated through the Upper Mississippi Valley district is on the order of 200,000 years. Fluid inclusion measurements and thermal maturities from biomarkers in the district reflect the duration of peak temperatures resulting from regional fluid circulation. On the basis of thermal considerations, the timing of fluorite mineralization in southern Illinois, and the northward-decreasing pattern of fluorine enrichment in sediments, we hypothesize that the principal flow direction was northward through the Cambrian and Ordovician aquifers of the Illinois Basin. A basin-scale flow system would result in mass transport (hydrocarbon migration, transport of metals in solution) and energy (heat) transport, which would in turn drive chemical reactions (for example, maturation of organic matter, mineralization, diagenetic reactions) within the Illinois Basin and at its margins.

Studies on questions of design and construction of chain scraper conveyors. [mining operations

NASA Technical Reports Server (NTRS)

Guder, H.

1980-01-01

The basic behavior of mining crushed goods in chain scraper conveyors was examined using a special test stand. The characteristics resistance lines of the upper end-piece were determined for conveyor idle as a function of the determinative crushed good characteristics (granular structure, moisture content, type of goods) on the size of the conveyor load, on the conveyor construction and on the stopped time of the conveyor. Crushed goods with a narrow granular profile and sphere-like grains caused about 35% greater resistance than fine coal and raw coal with broad granular profile. For goods containing water more than 10% by weight, the solids friction retreated in favor of flow friction. The coefficient of resistance decreased considerably in the range of lower speeds and then increased with increasing conveyor speed. The conveyance of sandstone ore required about 280% greater specific drive than the conveyance of raw coal. Resistance coefficients for coal and raw coal showed no dependence on the design of the conveyor. Start-up of loaded conveyors after longer stop times was simulated and the specific break-loose force was determined.

Correlation and taphonomy of late Cretaceous vertebrate localities in Fruitland and Kirtland formations, San Juan basin, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunt, A.P.

Most fossil vertebrates in the Fruitland and Kirtland formations occur in two narrow stratigraphic intervals. The upper interval comprises the approximately 30 m-thick Naashoibito Member of the Kirtland formation. Fossiliferous localities within this interval are physically correlatable within the small and continuous outcrop belt of this unit. The lower fossiliferous interval comprises a 20 m-thick sequence between the stratigraphically highest, thick coal bed (1 m thick) in the Fruitland Formation and distinctive brown tabular sandstones in the lower Kirtland formation, which differ in color and geometry from adjacent sandstone bodies. Localities within this interval occur in physically discontinuous outcrops, principallymore » between Hunter Wash in the northwest and Coal Creek in the southeast. These localities can be correlated utilizing the upper Fruitland coal, the lower Kirtland sandstones, and a series of volcanic ashes. Measurement of 38 stratigraphic sections and examination of more than 100 subsurface geophysical logs has allowed detailed correlation between the principal areas of vertebrate-fossil occurrences in Hunter Wash and the Fossil Forest. The occurrence of fossils in the Naashoibito is related to energy of depositional environment. Farther north, coarser deposits of the McDermott Member of the Animas Formation, which represent proximal facies of the Naashoibito, lack abundant fossil vertebrates. The geographic extent of vertebrate fossils in the upper Fruitland and lower Kirtland coincides with the extent of the tabular brown sandstones in the lower Kirtland and is related to Laramide downwarping of the central San Juan basin.« less

Power generation and its environmental consequences in Poland with special attention to the Upper Silesia region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hlawiczka, S.

1994-12-31

High consumption of coal that affected the prime energy balance, plus the absence of effective measures to protect the atmosphere from pollution, resulted in a widespread ecological threat to Poland. The paper describes the current air pollution conditions in Poland and basic measures that apply to the energy production sector that must by implemented. The most important and simplest method to reduce the emissions of SO{sub 2} and dust that result from burning coal is to introduce fuel enrichment and desulfurization.

A New Paleozoic Symmoriiformes (Chondrichthyes) from the Late Carboniferous of Kansas (USA) and Cladistic Analysis of Early Chondrichthyans

PubMed Central

Pradel, Alan; Tafforeau, Paul; Maisey, John G.; Janvier, Philippe

2011-01-01

Background The relationships of cartilaginous fishes are discussed in the light of well preserved three-dimensional Paleozoic specimens. There is no consensus to date on the interrelationship of Paleozoic chondrichthyans, although three main phylogenetic hypotheses exist in the current literature: 1. the Paleozoic shark-like chondrichthyans, such as the Symmoriiformes, are grouped along with the modern sharks (neoselachians) into a clade which is sister group of holocephalans; 2. the Symmoriiformes are related to holocephalans, whereas the other Paleozoic shark-like chondrichthyans are related to neoselachians; 3. many Paleozoic shark-like chondrichthyans, such as the Symmoriiformes, are stem chondrichthyans, whereas stem and crown holocephalans are sister group to the stem and crown neoselachians in a crown-chondrichthyan clade. This third hypothesis was proposed recently, based mainly on dental characters. Methodology/Principal Findings On the basis of two well preserved chondrichthyan neurocrania from the Late Carboniferous of Kansas, USA, we describe here a new species of Symmoriiformes, Kawichthys moodiei gen. et sp. nov., which was investigated by means of computerized X-ray synchrotron microtomography. We present a new phylogenetic analysis based on neurocranial characters, which supports the third hypothesis and corroborates the hypothesis that crown-group chondrichthyans (Holocephali+Neoselachii) form a tightly-knit group within the chondrichthyan total group, by providing additional, non dental characters. Conclusions/Significance Our results highlight the importance of new well preserved Paleozoic fossils and new techniques of observation, and suggest that a new look at the synapomorphies of the crown-group chondrichthyans would be worthwhile in terms of understanding the adaptive significance of phylogenetically important characters. PMID:21980367

A new paleozoic Symmoriiformes (Chondrichthyes) from the late Carboniferous of Kansas (USA) and cladistic analysis of early chondrichthyans.

PubMed

Pradel, Alan; Tafforeau, Paul; Maisey, John G; Janvier, Philippe

2011-01-01

The relationships of cartilaginous fishes are discussed in the light of well preserved three-dimensional Paleozoic specimens. There is no consensus to date on the interrelationship of Paleozoic chondrichthyans, although three main phylogenetic hypotheses exist in the current literature: 1. the Paleozoic shark-like chondrichthyans, such as the Symmoriiformes, are grouped along with the modern sharks (neoselachians) into a clade which is sister group of holocephalans; 2. the Symmoriiformes are related to holocephalans, whereas the other Paleozoic shark-like chondrichthyans are related to neoselachians; 3. many Paleozoic shark-like chondrichthyans, such as the Symmoriiformes, are stem chondrichthyans, whereas stem and crown holocephalans are sister group to the stem and crown neoselachians in a crown-chondrichthyan clade. This third hypothesis was proposed recently, based mainly on dental characters. On the basis of two well preserved chondrichthyan neurocrania from the Late Carboniferous of Kansas, USA, we describe here a new species of Symmoriiformes, Kawichthys moodiei gen. et sp. nov., which was investigated by means of computerized X-ray synchrotron microtomography. We present a new phylogenetic analysis based on neurocranial characters, which supports the third hypothesis and corroborates the hypothesis that crown-group chondrichthyans (Holocephali+Neoselachii) form a tightly-knit group within the chondrichthyan total group, by providing additional, non dental characters. Our results highlight the importance of new well preserved Paleozoic fossils and new techniques of observation, and suggest that a new look at the synapomorphies of the crown-group chondrichthyans would be worthwhile in terms of understanding the adaptive significance of phylogenetically important characters.

Sedimentology of the Pennsylvanian and Permian Strathearn Formation, Northern Carlin Trend, Nevada; with a section on microfossil controls on the age of the Strathearn Formation

USGS Publications Warehouse

Berger, Vladimir I.; Singer, Donald A.; Theodore, Ted G.; Harris, Anita G.; Stevens, Calvin H.

2001-01-01

Two framework-supported, poorly bedded conglomerate units of the middle Upper Pennsylvanian and middle Lower Permian Strathearn Formation belonging to the overlap assemblage of the Antler orogen are prominent in the northern Carlin trend. These horizons stratigraphically and temporally bracket thrust emplacement of a major allochthonous thrust plate of mainly quartzarenite of the Ordovician Vinini Formation. Lithologic and shape-ratio data from approximately 4,200 pebbles and cobbles at 17 sites as well as biostratigraphic data in the Strathearn, and their geologic implications, are included in this report. Conodont biofacies throughout the Strathearn Formation are normal marine and suggest middle shelf or deeper depositional environments. The conglomerate units roughly are similar in that they contain only chert and quartzarenite pebbles, but they differ in compositional proportions of the two lithologies. The relative proportion of quartzarenite pebbles increases sixfold in the middle Lower Permian upper conglomerate unit versus its content in the middle Upper Pennsylvanian lower unit, whereas chert pebbles predominate in both units. Various roundness categories of chert pebbles in both conglomerate units of the Strathearn show that the equant pebble class (B/A) = 1 clearly is represented strongly even in the subangular category, the lowest roundness categories for the pebbles. Thus, development of equant pebbles cannot be ascribed totally to a rounding process during predeposition transport. The equant character of many pebbles might, in part, be an original feature inherited from pre-erosion rock fractures and (or) bedding that control overall form of the fragments prior to their release to the transport environment. The allochthon of the Coyote thrust has been thrust above the lower conglomerate unit of the Strathearn during a regionally extensive contractional event in the late Paleozoic. The middle Lower Permian upper conglomerate unit, highest unit recognized in the Strathearn Formation, as well as similarly-aged dolomitic siltstone, onlap directly onto quartzarenite that comprises the allochthon of the Coyote thrust. The conglomerate units thus represent submarine fanglomerates whose quartz grains and quartzarenite fragments of variable roundness and shape were derived from a sedimentologically restored largely southeastward advancing late Paleozoic allochthonous lobe of mostly quartzarenite of the Ordovician Vinini Formation. Chert fragments in the conglomerates probably were derived mostly from Devonian Slaven Chert, including a widespread thick melange unit of the Slaven in the footwall of the Coyote thrust. Some chert pebbles may have been derived from the Ordovician Vinini Formation.

Granitoids of different geodynamic settings of Baikal region (Russia) their geochemical evolution and origin

NASA Astrophysics Data System (ADS)

Antipin, Viktor; Sheptyakova, Natalia

2016-04-01

In the southern folded framing of the Siberian craton the granitoid magmatism of different ages involves batholiths, small low-depth intrusions and intrusion-dyke belts with diverse mineral and geochemical characteristics of rocks. Granitoid formation could be related to the Early Paleozoic collision stage and intra-plate magmatism of the Late Paleozoic age of the geologic development of Baikal area. The Early Paleozoic granitoids of Khamar-Daban Ridge and Olkhon region revealed their closeness in age and composition. They were referred to syncollision S-type formations derived from gneiss-schistose substratum of metamorphic sequences. The magmatic rocks were classified into various geochemical types comprising formations of normal Na-alkalinity (migmatites and plagiogranites), calc-alkaline and subalkaline (K-Na granitoids, granosyenites and quartz syenites) series. It is significant, that plagiomigmatites and plagiogranites in all elements repeat the shape of the chart of normalized contents marked for trend of K-Na granitoids, but at considerably lower level of concentrations of all elements. This general pattern of element distribution might indicate similar anatectic origin of both granitoid types, but from crustal substrata distinguished by composition and geochemical features. Comparative geochemical analysis pointed out that the source of melts of the Early Paleozoic granitoids of the Olkhon (505-477 Ma) and Khamar-Daban (516-490 Ma) complexes of the Baikal region could be the crustal substratum, which is obviously the criterion for their formation in the collisional geodynamic setting. Using the Late Paleozoic subalkaline magmatism proceeding at the Khamar-Daban Range (Khonzurtay pluton, 331 Ma) as an example, it was found that the formation of monzodiorite-syenite-leucogranite series was considerably contributed by the processes of hybridism and assimilation through mixing of the upper mantle basaltoid magma derived melts of granitic composition. The involvement of the deep source is indicated by low Rb/Sr ratios and 87Sr/86Sr ratio (0.70592±0.00021) in rocks (Kazimirovskiy, 2006). The intra-plate biotite granites and leucogranites are represented by rare-metal geochemical type of rocks (311-321 Ma). Geochemical evolution promoted an increase of F, Li, Rb, Cs, Sn, Be, Ta, and Pb and a decrease of Ba, Sr, Zn, Zr, Th, and U contents in rare-metal granites, that reflects their formation from deeply differentiated residual magma. The substance of the lower crust could have the composition of biotite-bearing granulites rich in lithophyle rare elements. It is noteworthy, that the composition and isotope-geochemical features of the supposed magma-forming substratum correspond to the characteristics of the ancient Precambrian continental crust of the Southern Baikal region. These conclusions agree with the results of preceding studies of rare-metal granites in the other regions of Central Asia (Kovalenko et al, 1999). Research has been supported by RNF grant № 15-17-10010.

Chemical and physical characteristics of coal and carbonaceous shale samples from the Salt Range coal field, Punjab Province, Pakistan

USGS Publications Warehouse

Warwick, Peter D.; Shakoor, T.; Javed, Shahid; Mashhadi, S.T.A.; Hussain, H.; Anwar, M.; Ghaznavi, M.I.

1990-01-01

Sixty coal and carbonaceous shale samples collected from the Paleocene Patala Formation in the Salt Range coal field, Punjab Province, Pakistan, were analyzed to examine the relationships between coal bed chemical and physical characteristics and depositional environments. Results of proximate and ultimate analyses, reported on an as received basis, indicate that coal beds have an average ash yield of 24.23 percent, average sulfur content of 5.32 percent, average pyritic sulfur content of 4.07 percent, and average calorific value of 8943 Btu (4972 kcal/kg). Thirty five coal samples, analyzed on a whole coal, dry basis for selected trace elements and oxides, have anomalously high average concentrations of Ti, at O.3& percent; Zr, at 382 ppm; and Se, at 11.4 ppm, compared to world wide averages for these elements in coal.Some positive correlation coefficients, significant at a 0.01 level, are those between total sulfur and As, pyritic sulfur and As, total sulfur and sample location, organic sulfur and Se, calorific value (Btu) and sample location, and coal bed thickness and Se. Calorific values -for the samples, calculated on a moist, mineral matter free basis, indicate that the apparent rank of the coal is high volatile C bituminous.Variations observed in the chemical and physical characteristics of the coal beds may be related to depositional environments. Total ash yields and concentrations of Se and organic sulfur increase toward more landward depositional environments and may be related to an increase of fluvial influence on peat deposition. Variations in pyritic sulfur concentrations may be related to post-peat pyrite filled burrows commonly observed in the upper part of the coal bed. The thickest coal beds that have the lowest ash content, and highest calorific values, formed from peats deposited in back barrier, tidal flat environments of the central and western parts of the coal field. The reasons for correlations between Se and coal bed thickness and Se and ash content are not clear and may be a product of averaging.

Characteristics of the Roof Behaviors and Mine Pressure Manifestations During the Mining of Steep Coal Seam

NASA Astrophysics Data System (ADS)

Hong-Sheng, Tu; Shi-Hao, Tu; Cun, Zhang; Lei, Zhang; Xiao-Gang, Zhang

2017-12-01

A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a "voussoir beam" structure in the strata's dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof's behaviors during the mining of a steep seam.

Maps showing petroleum exploration intensity and production in major Cambrian to Ordovician reservoir rocks in the Anadarko Basin

USGS Publications Warehouse

Henry, Mitch; Hester, Tim

1996-01-01

The Anadarko basin is a large, deep, two-stage Paleozoic basin (Feinstein, 1981) that is petroleum rich and generally well explored. The Anadarko basin province, a geogrphic area used here mostly for the convenience of mapping and data management, is defined by political boundaries that include the Anadarko basin proper. The boundaries of the province are identical to those used by the U.S. Geological Survey (USGS) in the 1995 National Assessment of United Stated Oil and Gas Resources. The data in this report, also identical to those used in the national assessment, are from several computerized data bases including Nehring Research Group (NRG) Associates Inc., Significant Oil and Gas Fields of the United States (1992); Petroleum Information (PI), Inc., Well History Control System (1991); and Petroleum Information (PI), Inc., Petro-ROM: Production data on CD-ROM (1993). Although generated mostly in response to the national assessment, the data presented here arc grouped differently and arc displayed and described in greater detail. In addition, the stratigraphic sequences discussed may not necessarily correlate with the "plays" of the 1995 national assessment. This report uses computer-generated maps to show drilling intensity, producing wells, major fields, and other geologic information relevant to petroleum exploration and production in the lower Paleozoic part of the Anadarko basin province as defined for the U.S. Geological Survey's 1995 national petroleum assessment. Hydrocarbon accumulations must meet a minimum standard of 1 million barrels of oil (MMBO) or 6 billion cubic feet of gas (BCFG) estimated ultimate recovery to be included in this report as a major field or revoir. Mapped strata in this report include the Upper Cambrian to Lower Ordovician Arbuckle and Low Ordovician Ellenburger Groups, the Middle Ordovician Simpson Group, and the Middle to Upper Ordovician Viola Group.

Contrasting cratonal provenances for upper Cretaceous Valle Group quartzite clasts, Baja California

USGS Publications Warehouse

Kimbrough, D.L.; Abbott, G.; Smith, D.P.; Mahoney, J.B.; Moore, Thomas E.; Gehrels, G.E.; Girty, G.H.; Cooper, John D.

2006-01-01

Late Cretaceous Valle Group forearcbasin deposits on the Vizcaino Peninsula of Baja California Sur are dominated by firstcycle arc-derived volcanic-plutonic detritus derived from the adjacent Peninsular Ranges batholith. Craton-derived quartzite clasts are a minor but ubiquitous component in Valle Group conglomerates. The source of these clasts has implications for tectonic reconstructions and sediment-dispersal paths along the paleo-North American margin. Three strongly contrasting types of quartzite are recognized based on petrology and detrital zircon U-Pb geochronology. The first type is ultramature quartz arenite with well-rounded, highly spherical zircon grains. Detrital zircon ages from this type are nearly all >1.8 Ga with age distributions that closely match the distinctive Middle-Late Ordovician Peace River arch detrital signature of the Cordilleran margin. This type has been previously recognized from prebatholithic rocks in northeast Baja California (San Felipe quartzite). A second quartzite type is subarkosic sandstone with strong affinity to southwestern North America; important features of the age spectra are ~1.0-1.2 Ga, 1.42 and 1.66 Ga peaks representing cratonal basement, 500-300 Ma grains interpreted as recycled Appalachian-derived grains, and 284- 232 Ma zircon potentially derived from the Early Permian-Middle Triassic east Mexico arc. This quartzite type could have been carried to the continental margin during Jurassic time as outboard equivalents of Colorado Plateau eolianites. The third quartzite type is quartz pebble conglomerate with significant ~900- 1400 Ma and ~450-650 Ma zircon components, as well as mid- and late Paleozoic grains. The source of this type of quartzite is more problematic but could match either upper Paleozoic strata in the Oaxaca terrane of southern Mexico or a southwestern North America source. The similarity of detrital 98 zircon spectra in all three Valle Group quartzite types to rocks of the adjacent Cordilleran margin support previous interpretations that Valle Group forearc basin sediments were deposited in proximity to rocks on the mainland of northwest Mexico and southwestern United States.

Fault-related fluid flow, Beech Mountain thrust sheet, Blue Ridge Province, Tennessee-North Carolina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waggoner, W.K.; Mora, C.I.

1992-01-01

The latest proterozoic Beech Granite is contained within the Beech Mountain thrust sheet (BMTS), part of a middle-late Paleozoic thrust complex located between Mountain City and Grandfather Mountain windows in the western Blue Ridge of TN-NC. At the base of the BMTS, Beech Granite is juxtaposed against lower Paleozoic carbonate and elastics of the Rome Fm. along the Stone Mountain thrust on the southeaster margin of the Mountain City window. At the top of the BMTS, Beech Granite occurs adjacent to Precambrian mafic rocks of the Pumpkin Patch thrust sheet (PPTS). The Beech Granite is foliated throughout the BMTS withmore » mylonitization and localized cataclasis occurring within thrust zones along the upper and lower margins of the BMTS. Although the degree of mylonitization and cataclasis increases towards the thrusts, blocks of relatively undeformed granite also occur within these fault zones. Mylonites and thrusts are recognized as conduits for fluid movement, but the origin of the fluids and magnitude and effects of fluid migration are not well constrained. This study was undertaken to characterize fluid-rock interaction within the Beech Granite and BMTS. Extensive mobility of some elements/compounds within the thrust zones, and the isotopic and mineralogical differences between the thrust zones and interior of the BMTS indicate that fluid flow was focused within the thrust zones. The wide range of elevated temperatures (400--710 C) indicated by qz-fsp fractionations suggest isotopic disequilibrium. Using a more likely temperature range of 300--400 C for Alleghanian deformation, calculated fluid compositions indicate interactions with a mixture of meteoric-hydrothermal and metamorphic water with delta O-18 = 2.6--7.5[per thousand] for the upper thrust zone and 1.3 to 6.2[per thousand] for the lower thrust zone. These ranges are similar to isotopic data reported for other Blue Ridge thrusts and may represent later periods of meteoric water influx.« less

Himalayan gneiss dome formation in the middle crust and exhumation by normal faulting: New geochronology of Gianbul dome, northwestern India

USGS Publications Warehouse

Horton, Forrest; Lee, Jeffrey; Hacker, Bradley; Bowman-Kamaha'o, Meilani; Cosca, Michael A.

2015-01-01

A general lack of consensus about the origin of Himalayan gneiss domes hinders accurate thermomechanical modeling of the orogen. To test whether doming resulted from tectonic contraction (e.g., thrust duplex formation, antiformal bending above a thrust ramp, etc.), channel flow, or via the buoyant rise of anatectic melts, this study investigates the depth and timing of doming processes for Gianbul dome in the western Himalaya. The dome is composed of Greater Himalayan Sequence migmatite, Paleozoic orthogneiss, and metasedimentary rock cut by multiple generations of leucogranite dikes. These rocks record a major penetrative D2 deformational event characterized by a domed foliation and associated NE-SW–trending stretching lineation, and they are flanked by the top-down-to-the-SW (normal-sense) Khanjar shear zone and the top-down-to-the-NE (normal sense) Zanskar shear zone (the western equivalent of the South Tibetan detachment system). Monazite U/Th-Pb geochronology records (1) Paleozoic emplacement of the Kade orthogneiss and associated granite dikes; (2) prograde Barrovian metamorphism from 37 to 33 Ma; (3) doming driven by upper-crustal extension and positive buoyancy of decompression melts between 26 and 22 Ma; and (4) the injection of anatectic melts into the upper levels of the dome—neutralizing the effects of melt buoyancy and potentially adding strength to the host rock—by ca. 22.6 Ma on the southwestern flank and ca. 21 Ma on the northeastern flank. As shown by a northeastward decrease in 40Ar/39Ar muscovite dates from 22.4 to 20.2 Ma, ductile normal-sense displacement within the Zanskar shear zone ended by ca. 22 Ma, after which the Gianbul dome was exhumed as part of a rigid footwall block below the brittle Zanskar normal fault, tilting an estimated 5°–10°SW into its present orientation.

Geology, coal resources, and chemical analyses of coal from the Fruitland Formation, Kimbeto EMRIA study site, San Juan County, New Mexico

USGS Publications Warehouse

Schneider, Gary B.; Hildebrand, Rick T.; Affolter, Ronald H.

1979-01-01

The Kimbeto EMRIA study site, an area of about 20 square miles (52 km2), is located on the south margin of the San Juan Basin on the gently northward-dipping strata of the Upper Cretaceous Fruitland Formation and the Kirtland Shale. The coal beds are mainly in the lower 150 feet (45 m) of the Fruitland Format ion. Coal resources--measured, indicated, and inferred--with less than 400 feet (120 m) of overburden in the site are 69,085,000 short tons (62,660,100 metric tons), 369,078,000 short tons (334,754,000 metric tons), and 177,803,000 short tons (161,267,000 metric tons) respectively. About 68 percent of these resources are overlain by 200 feet (60 m) or less of overburden. The apparent rank of the coal ranges from subbituminous B to subbituminous A. The average Btu/lb value of 14 core samples from the site on the as-received basis is 8,240 (4580 Kcal/kg), average ash content is 23.4 percent, and average sulfur content is 0.5 percent. Analyses of coal from the Kimbeto EMRIA study site show significantly higher ash content and significantly lower contents of volatile matter, fixed carbon, carbon, and a significantly lower heat of combustion when compared with other coal analyses from the Rocky Mountain province.

Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada

USGS Publications Warehouse

Yigit, O.; Nelson, E.P.; Hitzman, M.W.; Hofstra, A.H.

2003-01-01

The Gold Bar district in the southern Roberts Mountains, 48 km northwest of Eureka, Nevada, contains one main deposit (Gold Bar), five satellite deposits, and other resources. Approximately 0.5 Moz of gold have been recovered from a resource of 1,639,000 oz of gold in Carlin-type gold deposits in lower plate, miogeoclinal carbonate rocks below the Roberts Mountains thrust. Host rocks are unit 2 of the Upper Member of the Devonian Denay Formation and the Bartine Member of the McColley Canyon Formation. Spatial and temporal relations between structures and gold mineralization indicate that both pre-Tertiary and Tertiary structures were important controls on gold mineralization. Gold mineralization occurs primarily along high-angle Tertiary normal faults, some of which are reactivated reverse faults of Paleozoic or Mesozoic age. Most deposits are localized at the intersection of northwest- and northeast-striking faults. Alteration includes decalcification, and to a lesser extent, silicification along high-angle faults. Jasperoid (pervasive silicification), which formed along most faults and in some strata-bound zones, accounts for a small portion of the ore in every deposit. In the Gold Canyon deposit, a high-grade jasperoid pipe formed along a Tertiary normal fault which was localized along a zone of overturned fault-propagation folds and thrust faults of Paleozoic or Mesozoic age.

Onset of oxidative weathering of continents recorded in the geochemistry of ancient glacial diamictites

NASA Astrophysics Data System (ADS)

Gaschnig, Richard M.; Rudnick, Roberta L.; McDonough, William F.; Kaufman, Alan J.; Hu, Zhaochu; Gao, Shan

2014-12-01

Glacial diamictites deposited in the Mesoarchean, Paleoproterozoic, Neoproterozoic, and Paleozoic eras record temporal variations in their average compositions that reflect the changing composition of the upper continental crust (UCC). Twenty six of the 27 units studied show elevated chemical index of alternation (CIA) and low Sr abundances, regardless of their age, documenting pervasive weathering of the average UCC. Lower abundances of transition metals reflect a shift towards more felsic crustal compositions after the Archean. Superimposed on this chemical difference is the signal of the rise of oxidative weathering of the continents, recorded by changes in the absolute and relative abundances of the redox sensitive elements Mo and V. Neoproterozoic and Paleozoic diamictites show pervasive depletion in Mo and V, reflecting their loss from the continents due to increasing intensity of oxidative weathering, as also recorded in some of the Paleoproterozoic diamictites. A few of the Paleoproterozoic diamictites deposited after the Great Oxidation Event show no depletion in Mo and V (e.g., Gowganda), but such signatures could be inherited from their provenance. In contrast, the pre-GOE Duitschland diamictite (ca. 2.3-2.5 Ga) from South Africa reveals evidence of intense oxidative weathering (i.e., large depletions in Mo), supporting a growing body of observations showing the presence of measurable atmospheric oxygen prior to permanent loss of the mass independent fractionation signal in sulfur isotopes.

Analysis of hydrocarbons generated in coalbeds

NASA Astrophysics Data System (ADS)

Butala, Steven John M.

This dissertation describes kinetic calculations using literature data to predict formation rates and product yields of oil and gas at typical low-temperature conditions in coalbeds. These data indicate that gas formation rates from hydrocarbon thermolysis are too low to have generated commercial quantities of natural gas, assuming bulk first-order kinetics. Acid-mineral-catalyzed cracking, transition-metal-catalyzed hydrogenolysis of liquid hydrocarbons, and catalyzed CO2 hydrogenation form gas at high rates. The gaseous product compositions for these reactions are nearly the same as those for typical natural coalbed gases, while those from thermal and catalytic cracking are more representative of atypical coalbed gases. Three Argonne Premium Coals (Upper-Freeport, Pittsburgh #8 and Lewiston-Stockton) were extracted with benzene in both Soxhlet and elevated pressure extraction (EPE) systems. The extracts were compared on the basis of dry mass yield and hydrocarbon profiles obtained by gas chromatography/mass spectrometry. The dry mass yields for the Upper-Freeport coal gave consistent results by both methods, while the yields from the Pittsburgh #8 and Lewiston-Stockton coals were greater by the EPE method. EPE required ˜90 vol. % less solvent compared to Soxhlet extraction. Single-ion-chromatograms of the Soxhlet extracts all exhibited bimodal distributions, while those of the EPE extracts did not. Hydrocarbons analyzed from Greater Green River Basin samples indicate that the natural oils in the basin originated from the coal seams. Analysis of artificially produced oil indicates that hydrous pyrolysis mimics generation of C15+ n-alkanes, but significant variations were found in the branched alkane, low-molecular-weight n-alkanes, and high-molecular-weight aromatic hydrocarbon distributions.

Petrography, geochemistry, and depositional setting of the San Pedro and Santo Tomas coal zones: Anomalous algae-rich coals in the middle part of the Claiborne Group (Eocene) of Webb County, Texas

USGS Publications Warehouse

Warwick, Peter D.; Hook, Robert W.

1995-01-01

Two coal zones, the San Pedro and the overlying Santo Tomas, are present for nearly 35 km in outcrop, surface and underground mines, and shallow drill holes along the strike of the middle part of the Claiborne Group (Eocene) in Webb County, Texas. A sandstone-dominated interval of 25 to 35 m separates the two coal zones, which range up to 3 m in thickness. Each coal zone contains carbonaceous shales, thin (<0.75 m) impure coal beds, and thin (<0.85 m) but commercially significant nonbanded coal beds. The nonbanded coals are different from other Tertiary coals of the Gulf of Mexico Coastal Plain: unlike lignites that are typical of the older Wilcox Group (Paleocene-Eocene) and younger Jackson Group (Eocene), nonbanded coals of the Claiborne Group have high vitrinite-reflectance values (0.53 Rmax) and high calorific yields (average 6670 kcal/kg or 12,000 Btu, dry basis). The coals are weakly agglomerating (free-swelling index is 1.5–2.0) and have an apparent rank of high-volatile bituminous.The coal-bearing portion of the middle Claiborne Group in the Rio Grande area represents a fining-upward transition from sandstone-dominated, marine-influenced, lower delta plain depositional environments to more inland, mudstone-rich, predominantly freshwater deltaic settings. Discontinuities within the San Pedro coal zone are attributed mainly to the influence of contemporaneous deposition of distributary mouth-bar sand bodies. The less variable nature of the Santo Tomas coal zone reflects its origin in the upper part of an interlobe basin that received only minor clastic influx.Petrographic attributes of the nonbanded coals indicate that they formed subaqueously in fresh to possibly brackish waters. A highly degraded groundmass composed of eugelinite is the main petrographic component (approximately 71%, mineral-matter-free basis). An enriched liptinite fraction (approximately 23%) probably accounts for unusually high calorific values. There is negligible inertinite. Petrographic study of polished blocks indicates that approximately 10 percent of the nonbanded coal from both coal zones is composed of green algae fructifications, which also occur in clastic rocks of the coal-bearing interval. Such algal material cannot be identified or quantified by conventional coal petrographic techniques that utilize particle pellets or by palynological analyses that include acid preparation.

Foreland crustal structure of the New York recess, northeastern United States

USGS Publications Warehouse

Herman, G.C.; Monteverde, D.H.; Schlische, R.W.; Pitcher, D.M.

1997-01-01

A new structural model for the northeast part of the Central Appalachian foreland and fold-and-thrust belt is based on detailed field mapping, geophysical data, and balanced cross-section analysis. The model demonstrates that the region contains a multiply deformed, parautochthonous fold-and-thrust system of Paleozoic age. Our interpretations differ from previous ones in which the entire region north of the Newark basin was considered to be allochthonous. The new interpretation requires a substantial decrease in Paleozoic tectonic shortening northeastward from adjacent parts of the Central Appalachian foreland and illustrates the common occurrence of back-thrusting within the region. During early Paleozoic time northern New Jersey consisted of a Taconic orogenic foreland in which cover folds (F1) involved lower Paleozoic carbonate and flysch overlying Middle Proterozoic basement. F1 folds are open and upright in the foreland and more gently inclined to recumbent southeastward toward the trace of the Taconic allochthons. F1 structures were cut and transported by a fold-and-thrust system of the Allegheny orogeny. This thrust system mostly involves synthetic faults originating from a master decollement rooted in Proterozoic basement. Antithetic faults locally modify early synthetic overthrusts and S1 cleavage in lower Paleozoic cover and show out-of-sequence structural development. The synthetic parts of the regional thrust system are bounded in the northwestern foreland by blind antithetic faults interpreted from seismic-reflection data. This antithetic faulting probably represents Paleozoic reactivation of Late Proterozoic basement faults. Tectonic contraction in overlying cover occurred by wedge faulting where synthetic and antithetic components of the foreland fault system overlap. S2 cleavage in the Paleozoic cover stems from Alleghanian shortening and flattening and commonly occurs in the footwall of large overthrust sheets. Paleozoic structures in Proterozoic basement include fault blocks bounded by high-angle faults and low- to moderate-angle shear zones that locally produce overlying cover folds. Broad and open folds in basement probably reflect shear-zone displacement of subhorizontal foliation. Our cross-section interpretations require limited involvement of lower Paleozoic cover folds in the footwalls of major overthrust faults. Palinspastic restoration of F1 folds produces an arched passive-margin sequence. The tectonic contraction for the Valley and Ridge province and southeastern Pocono Plateau is about 25 km, and tectonic wedge angles are 8??-11??.

Late Paleozoic magmatism in South China: Oceanic subduction or intracontinental orogeny?

NASA Astrophysics Data System (ADS)

Liu, Q.; Yu, J.; Zhao, G.

2013-12-01

The significant late Paleozoic magmatism has been widely recognized in the East Asian Blocks, which sheds a light on the assembly and break-up of the Pangea supercontinent. As one of major components in East Asia, however, the South China Block (SCB) does not have much late Paleozoic magmatism recognized. Here we report a gneissic granite intrusion in northeastern Fujian Province, eastern SCB. It is a S-type granite characterized by high K2O and Al2O3, and low SiO2 and Na2O with a high A/CNK ratio of 1.22. Zircons with stubby morphology from this gneissic granite yield 206Pb/238U ages ranging from 326 Ma to 301 Ma with a weighted average age of 313×4 Ma, and negative epsilonHf(t) values from -8.35 to -1.74 with two-stage Hf model ages of 1.43 to 1.84 Ga. This S-type granite was probably originated from late Paleoproterozoic crust during an intracontinental orogeny, not under oceanic subduction. Integrated with previous results on the paleogeographic reconstruction of the SCB, the nature of Paleozoic basins, Early Permian volcanism and U-Pb-Hf isotope of detrital zircons from the late Paleozoic to early Mesozoic sedimentary rocks, our data support a late Paleozoic orogeny in the SCB, which may have included Late Carboniferous (340-310 Ma) compressive episode and Early Permian (287-270 Ma) post-orogenic or intraplate extensive episode. Our interpretation is consistent with the late Paleozoic orogenic events recognized in other Pangea microcontinents, and thus provides a window for the reconstruction of Pangea. Acknowledgements: NSFC (41190070, 41190075)

Can Switching from Coal to Shale Gas Bring Net Carbon Reductions to China?

PubMed

Qin, Yue; Edwards, Ryan; Tong, Fan; Mauzerall, Denise L

2017-03-07

To increase energy security and reduce emissions of air pollutants and CO 2 from coal use, China is attempting to duplicate the rapid development of shale gas that has taken place in the United States. This work builds a framework to estimate the lifecycle greenhouse gas (GHG) emissions from China's shale gas system and compares them with GHG emissions from coal used in the power, residential, and industrial sectors. We find the mean lifecycle carbon footprint of shale gas is about 30-50% lower than that of coal in all sectors under both 20 year and 100 year global warming potentials (GWP 20 and GWP 100 ). However, primarily due to large uncertainties in methane leakage, the upper bound estimate of the lifecycle carbon footprint of shale gas in China could be approximately 15-60% higher than that of coal across sectors under GWP 20 . To ensure net GHG emission reductions when switching from coal to shale gas, we estimate the breakeven methane leakage rates to be approximately 6.0%, 7.7%, and 4.2% in the power, residential, and industrial sectors, respectively, under GWP 20 . We find shale gas in China has a good chance of delivering air quality and climate cobenefits, particularly when used in the residential sector, with proper methane leakage control.

A bibliography of Paleozoic Crustacea from 1698 to 1889, including a list of North American species and a systematic arrangement of genera

USGS Publications Warehouse

Vogdes, Anthony Wayne

1890-01-01

The sole object of this bulletin is to give a general view of the literature on the Paleozoic Crustacea and to aid students and paleontologists in their researches. It is the result of more or less constant work during the past ten years.In its compilation I have examined almost every reference before recording it; those not so examined are indicated by a star (*) following the title.For convenience, the subject-matter has been arranged as follows:Part I. List of authors, including a brief index of the genera described in each work. Part II. A catalogue of the North American Paleozoic trilobites. Part III. The non-trilobitic Paleozoic Crustacea, with a list of the species.

Assessment of the petroleum, coal, and geothermal resources of the Economic Community of West African States (ECOWAS) region

USGS Publications Warehouse

Mattick, R. E.

1982-01-01

Approximately 85 percent of the land area of the ECOWAS (Economic Community of West African States) region is covered by basement rocks (igneous and highly metamorphosed rocks) or relatively thin layers of Paleozoic, Upper Precambrian, and 'Continental Intercalaire? sedimentary rocks. These areas have little or no petroleum potential. Areas of the ECOWAS region that have potential for petroleum production or potential for increased petroleum production include the narrow belt of sedimentary rocks that stretches along the continental margin from Mauritania to Nigeria and the Niger Delta and the Benue depression. The Senegal Basin, located on the continental margin of Mauritania, Senegal, Gambia, Guinea Bissau, and Guinea, has been intensely explored by the oil industry and most of the larger structures onshore and on the shelf probably have been tested by drilling with little or no resulting commercial production. Unless basic ideas pertaining to the petroleum geology of the Senegal Basin are revised, future discoveries are expected to be limited to small fields overlooked by industry at a time when petroleum prices were low. On the continental shelf of Sierra Leone and the continental shelf of northeast and central Liberia, the sedimentary rocks are relatively thin, and industry has shown little interest in the area. On the continental rise of these countries, however, the sedimentary section, deposited in a complex fault-block system, increases in thickness. A renewal of industry interest in this deep-water area will probably follow further development of deep-water production technology. A recent oil discovery on the continental slope off the Ivory Coast is expected to spur further exploration offshore of southeastern Liberia, Ivory Coast, Ghana, Togo, and Benin. This relatively unexplored area in the Gulf of Guinea has good possibilities .for the discovery of giant oil fields. Nigeria's oil development from the Niger Delta may have peaked, as 13 of 14 giant oil fields were discovered prior to 1969 and the greatest number of fields were discovered in the period 1965 through 1967. Like delta regions in other parts of the world, individual oil fields of the Niger Delta are small to medium by world standards and future discoveries, therefore, are likely to reflect this reality. The natural gas resources of the Niger Delta, unlike its oil resources, are comparatively underdeveloped. Parts of the Benue depression in Nigeria and Niger could contain significant deposits of petroleum. The lower Benue depression, immediately north of the Niger Delta, has been extensively explored by drilling. Except for noncommercial discoveries of oil and gas and traces of oil and gas on the ground surface, the results of exploration in the lower Benue depression were negative. However, in the Lake Chad area of Chad and in southern Chad near the Central African Republic boundary, oil and gas discoveries were made just prior to the cessation of all drilling and exploration activity in early 1979. It is rumored that these discoveries may be large although little information is available. The relation between the two areas in Chad and their overall relation to the Benue depression is poorly understood; however, the possibility of thick sedimentary sections containing Cretaceous marine source rock and Tertiary reservoir beds-all contained within grabens in a highly faulted failed-arm system subjected to high heat flow--is attractive. Of the ECOWAS countries, only Nigeria and Niger produce coal commercially. Nigeria produces subbituminous coal from Paleocene-Maestrichtian and Maestrichtian (Late Cretaceous) age rocks of the Niger Delta region; reserves are estimated, on the basis of extensive drilling, to be 350 million tons (standard coal equivalent). In addition, lignite deposits of the Niger Delta appear to be large but have not been developed. Niger produces small amounts of coal used locally by uranium mine and mill operations from C

High-Resolution Zircon U-Pb CA-TIMS Dating of the Carboniferous—Permian Successions, Paraná Basin, Brazil

NASA Astrophysics Data System (ADS)

Griffis, N. P.; Mundil, R.; Montanez, I. P.; Isbell, J.; Fedorchuk, N.; Lopes, R.; Vesely, F.; Iannuzzi, R.

2015-12-01

The late Paleozoic Ice Age (LPIA) is Earth's only record of a CO2-forced climatic transition from an icehouse to greenhouse state in a vegetated world. Despite a refined framework of Gondwanan ice distribution, questions remain about the timing, volume, and synchronicity of high-latitude continental ice and the subsequent deglaciation. These questions ultimately preclude our understanding of linkages between ice volume, sea level, and high- and low-latitude climate. Poor constraints on the timing and synchronicity of glacial and interglacial transitions reflect a lack of high-resolution radioisotopic dates from high-latitude, ice-proximal Carboniferous-Permian successions. The Rio Bonito Fm in Rio Grande do Sul State of southern Brazil hosts the oldest non-glaciogenic Carboniferous- Permian deposits of the Paraná Basin, thus recording the icehouse-to-greenhouse transition. Despite a widespread effort over the last two decades to constrain these deposits in time by means of U-Pb zircon geochronology, published data sets of the Candiota and Faxinal coals of the Rio Bonito Fm host discrepancies that may reflect post- eruptive open system behavior of zircon and analytical artifacts. These discrepancies have hindered the correlation of the Candiota and Faxinal sediments within the larger Gondwanan framework. Here we present the first U-Pb ages on closed system single zircons using CA-TIMS techniques on Permo-Carboniferous ash deposits of the Paraná Basin. Preliminary results indicate two major and distinct coal-forming periods that are separated by ca 10 Ma. Our results and conclusions are not in agreement with multi- crystal U-Pb TIMS and SIMS ages that suggest coeval deposition of the Candiota and Faxinal coals. CA-TIMS analyses applied to zircons from additional ash deposits are aimed at constructing a robust chronostratigraphic framework for the Carboniferous- Permian succession of the Paraná Basin, which will facilitate a better understanding of the timing and ice dynamics of the LPIA.

Origin and significance of high nickel and chromium concentrations in pliocene lignite of the Kosovo Basin, Serbia

USGS Publications Warehouse

Ruppert, L.; Finkelman, R.; Boti, E.; Milosavljevic, M.; Tewalt, S.; Simon, N.; Dulong, F.

1996-01-01

Trace element data from 59 Pliocene lignite cores from the lignite field in the Kosovo Basin, southern Serbia, show localized enrichment of Ni and Cr (33-304 ppm and 8-176 ppm, respectively, whole-coal basis). Concentrations of both elements decrease from the western and southern boundaries of the lignite field. Low-temperature ash and polished coal pellets of selected bench and whole-coal samples were analyzed by X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray analyses. These analyses show that most of the Ni and Cr are incorporated in detrital and, to a lesser degree, in authigenic minerals. The Ni- and Cr-bearing detrital minerals include oxides, chromites, serpentine-group minerals and rare mixed-layer clays. Possible authigenic minerals include Ni-Fe sulfates and sulfides. Analyses of three lignite samples by a supercritical fluid extraction technique indicate that some (1-11%) of the Ni is organically bound. Ni- and Cr-bearing oxides, mixed-layer clays, chromites and serpentine-group minerals were also identified in weathered and fresh samples of laterite developed on serpentinized Paleozoic peridotite at the nearby Glavica and C??ikatovo Ni mines. These mines are located along the western and northwestern rim, respectively, of the Kosovo Basin, where Ni contents are highest. The detrital Ni- and Cr-bearing minerals identified in lignite samples from the western part of the Kosovo Basin may have been transported into the paleoswamp by rivers that drained the two Paleocene laterites. Some Ni may have been transported directly into the paleoswamp in solution or, alternatively, Ni may have been leached from detrital minerals by acidic peat water and adsorbed onto organic matter and included into authigenic mineral phases. No minable source of Ni and Cr is known in the southern part of the lignite field; however, the mineral and chemical data from the lignite and associated rocks suggest that such a source area may exist.

Use of the high-resolution satellite images for detection of fractures related to the ore deposits

NASA Astrophysics Data System (ADS)

Cruz-Mondaca, M.; Soto-Pinto, C. A.; Arellano-Baeza, A. A.

2012-12-01

The Aster and GeoEye satellite high-resolution images were used to detect the structures related to the fracturing of the upper crust in the North of Chile. In particular, lineament analysis has been applied to detect the presence of epithermal fluids of low sulfurization associated with the Paleozoic ore deposits. These results have been compared with the location of the minerals altered by the presence of geothermal fluids detected using the spectral libraries. Later, the presence of fractures has been corroborated during recognition of fractures in situ and the geochemical analysis of samples of minerals altered by the presence of fluids. It was shown that the results obtained are relevant for the gold vein detection.

Maps of upper Mississippi embayment Paleozoic and Precambrian rocks

USGS Publications Warehouse

Dart, Richard L.

1995-01-01

The Mississippi Embayment regional seismic hazard (Fuller, 1912; Nuttli, 1973, 1982, 1983), associated with the New Madrid seismic zone (NMSZ) is attributed to displacement on seismogenic structures primarily within the failed Reelfoot rift (Burke and Dewey, 1973; Ervin and McGinnis, 1975; Hildenbrand, 1977; Johnston and Shedlock, 1992). Hildenbrand and others (1977) and Hildenbrand (1985) used potential field data to show the northeast trend of the buried rift and the existence of related intrusive bodies. The Mississippi Valley graben (Hildenbrand and others, 1977; Kane and others, 1981; Hildenbrand, 1985; Wheeler and others, 1993), also referred to as the Reelfoot graben (Hildenbrand and Hendricks, 1995), is here considered to be the structural expression of the Reelfoot rift at the Precambrian basement surface.

Shale hydrocarbon reservoirs: some influences of tectonics and paleogeography during deposition: Chapter 2

USGS Publications Warehouse

Eoff, Jennifer D

2014-01-01

Fundamental to any of the processes that acted during deposition, however, was active tectonism. Basin type can often distinguish self-sourced shale plays from other types of hydrocarbon source rocks. The deposition of North American self-sourced shale was associated with the assembly and subsequent fragmentation of Pangea. Flooded foreland basins along collisional margins were the predominant depositional settings during the Paleozoic, whereas deposition in semirestricted basins was responsible along the rifted passive margin of the U.S. Gulf Coast during the Mesozoic. Tectonism during deposition of self-sourced shale, such as the Upper Jurassic Haynesville Formation, confined (re)cycling of organic materials to relatively closed systems, which promoted uncommonly thick accumulations of organic matter.

Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnhart, Elliott P.; Weeks, Edwin P.; Jones, Elizabeth J. P.

Biogenic coalbed methane (CBM), a microbially-generated source of natural gas trapped within coal beds, is an important energy resource in many countries. Specific bacterial populations and enzymes involved in coal degradation, the potential rate-limiting step of CBM formation, are relatively unknown. The U.S. Geological Survey (USGS) has established a field site, (Birney test site), in an undeveloped area of the Powder River Basin (PRB), with four wells completed in the Flowers-Goodale coal bed, one in the overlying sandstone formation, and four in overlying and underlying coal beds (Knoblach, Nance, and Terret). The nine wells were positioned to characterize the hydraulicmore » conductivity of the Flowers-Goodale coal bed and were selectively cored to investigate the hydrogeochemistry and microbiology associated with CBM production at the Birney test site. Aquifer-test results indicated the Flowers-Goodale coal bed, in a zone from about 112-120 m below land surface at the test site, had very low hydraulic conductivity (0.005 m/d) compared to other PRB coal beds examined. Consistent with microbial methanogenesis, groundwater in the coal bed and overlying sandstone contain dissolved methane (46 mg/L average) with low δ 13C values (-67‰ average), high alkalinity values (22 meq/kg average), relatively positive δ 13C-DIC values (4‰ average), and no detectable higher chain hydrocarbons, NO 3 -, or SO 4 2-. Bioassay methane production was greatest at the upper interface of the Flowers-Goodale coal bed near the overlying sandstone. Pyrotag analysis identified Aeribacillus as a dominant in situ bacterial community member in the coal near the sandstone and statistical analysis indicated Actinobacteria predominated coal core samples compared to claystone or sandstone cores. These bacteria, which previously have been correlated with hydrocarbon-containing environments such as oil reservoirs, have demonstrated the ability to produce biosurfactants to break down hydrocarbons. As a result, identifying microorganisms involved in coal degradation and the ydrogeochemical conditions that promote their activity is crucial to understanding and improving in situ CBM production.« less

Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed

DOE PAGES

Barnhart, Elliott P.; Weeks, Edwin P.; Jones, Elizabeth J. P.; ...

2016-05-04

Biogenic coalbed methane (CBM), a microbially-generated source of natural gas trapped within coal beds, is an important energy resource in many countries. Specific bacterial populations and enzymes involved in coal degradation, the potential rate-limiting step of CBM formation, are relatively unknown. The U.S. Geological Survey (USGS) has established a field site, (Birney test site), in an undeveloped area of the Powder River Basin (PRB), with four wells completed in the Flowers-Goodale coal bed, one in the overlying sandstone formation, and four in overlying and underlying coal beds (Knoblach, Nance, and Terret). The nine wells were positioned to characterize the hydraulicmore » conductivity of the Flowers-Goodale coal bed and were selectively cored to investigate the hydrogeochemistry and microbiology associated with CBM production at the Birney test site. Aquifer-test results indicated the Flowers-Goodale coal bed, in a zone from about 112-120 m below land surface at the test site, had very low hydraulic conductivity (0.005 m/d) compared to other PRB coal beds examined. Consistent with microbial methanogenesis, groundwater in the coal bed and overlying sandstone contain dissolved methane (46 mg/L average) with low δ 13C values (-67‰ average), high alkalinity values (22 meq/kg average), relatively positive δ 13C-DIC values (4‰ average), and no detectable higher chain hydrocarbons, NO 3 -, or SO 4 2-. Bioassay methane production was greatest at the upper interface of the Flowers-Goodale coal bed near the overlying sandstone. Pyrotag analysis identified Aeribacillus as a dominant in situ bacterial community member in the coal near the sandstone and statistical analysis indicated Actinobacteria predominated coal core samples compared to claystone or sandstone cores. These bacteria, which previously have been correlated with hydrocarbon-containing environments such as oil reservoirs, have demonstrated the ability to produce biosurfactants to break down hydrocarbons. As a result, identifying microorganisms involved in coal degradation and the ydrogeochemical conditions that promote their activity is crucial to understanding and improving in situ CBM production.« less

Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed

USGS Publications Warehouse

Barnhart, Elliott P.; Weeks, Edwin P.; Jones, Elizabeth J.P.; Ritter, Daniel J.; McIntosh, Jennifer C.; Clark, Arthur C.; Ruppert, Leslie F.; Cunningham, Alfred B.; Vinson, David S.; Orem, William H.; Fields, Matthew W.

2016-01-01

Biogenic coalbed methane (CBM), a microbially-generated source of natural gas trapped within coal beds, is an important energy resource in many countries. Specific bacterial populations and enzymes involved in coal degradation, the potential rate-limiting step of CBM formation, are relatively unknown. The U.S. Geological Survey (USGS) has established a field site, (Birney test site), in an undeveloped area of the Powder River Basin (PRB), with four wells completed in the Flowers-Goodale coal bed, one in the overlying sandstone formation, and four in overlying and underlying coal beds (Knoblach, Nance, and Terret). The nine wells were positioned to characterize the hydraulic conductivity of the Flowers-Goodale coal bed and were selectively cored to investigate the hydrogeochemistry and microbiology associated with CBM production at the Birney test site. Aquifer-test results indicated the Flowers-Goodale coal bed, in a zone from about 112 to 120 m below land surface at the test site, had very low hydraulic conductivity (0.005 m/d) compared to other PRB coal beds examined. Consistent with microbial methanogenesis, groundwater in the coal bed and overlying sandstone contain dissolved methane (46 mg/L average) with low δ13C values (−67‰ average), high alkalinity values (22 meq/kg average), relatively positive δ13C-DIC values (4‰ average), and no detectable higher chain hydrocarbons, NO3−, or SO42−. Bioassay methane production was greatest at the upper interface of the Flowers-Goodale coal bed near the overlying sandstone. Pyrotag analysis identified Aeribacillus as a dominant in situbacterial community member in the coal near the sandstone and statistical analysis indicated Actinobacteria predominated coal core samples compared to claystone or sandstone cores. These bacteria, which previously have been correlated with hydrocarbon-containing environments such as oil reservoirs, have demonstrated the ability to produce biosurfactants to break down hydrocarbons. Identifying microorganisms involved in coal degradation and the hydrogeochemical conditions that promote their activity is crucial to understanding and improving in situ CBM production.

Petrology and palynology of the No. 5 block coal bed, northeastern Kentucky

USGS Publications Warehouse

Hower, J.C.; Eble, C.F.; Rathbone, R.F.

1994-01-01

The upper Middle Pennsylvanian (middle Westphalian D equivalent) No. 5 Block coal bed (Eastern Kentucky Coal Field of the Central Appalachian Basin) is a low-sulfur, compliance coal resource, dominantly comprised of dull, inertinite-rich lithotypes. Ash yields tend to be highly variable in the No. 5 Block, as does bed thickness and frequency of bed splitting. This study describes the petrographic, palynologic and geochemical characteristics of the No. 5 Block coal bed, and reports on some temporal and spatial trends among these parameters in eastern-northeastern Kentucky. Petrographically the No. 5 Block coal is predominated by dull, often high-ash lithotypes, with inertinite contents commonly exceeding 30% (mmf). The coal thins to the north-northwest where it tends to be higher in vitrinite and sulfur content. Representatives of large and small lycopsids and ferns (both tree-like and small varieties) dominate the No. 5 Block coal bed palynoflora. Calamite spores and cordaite pollen also occur but are less abundant. Small lycopsid (Densosporites spp. and related crassicingulate genera) and tree fern (e.g. Punctatisporites minutus, Laevigatosporites globosus) spore taxa are most abundant in dull lithotypes. Bright lithotypes contain higher percentages of arboreous lycopsid spores (Lycospora spp.). Regionally, the No. 5 Block coal contains abundant Torispora securis, a tree fern spore specially adapted for desiccation prevention. This, along with overall high percentages of inertinite macerals, suggest that peat accumulation may have taken place in a seasonally dry (?) paleoclimate. The No. 5 Block coal bed thickens rather dramatically in a NW-SE direction, as does the frequency of coal bed splitting. This phenomenon appears to be related to increased accomodation space in the southeastern portion of the study area, perhaps via penecontemporaneous growth faulting. Maceral and palynomorph variations within the bed correspond with these changes. Thin coal along the northwestern margin tends to be vetrinite rich and contains abundant Lycospora, perhaps reflecting relatively stable peat-forming conditions. Thicker coal to the southeast contains more inertinite, high-ash coal layers, and inorganic partings. Spore floras contain more small lycopsid and tree fern components and are temporally variable, perhaps indicating a more unstable peat-forming environment. ?? 1994.

Oil-generating coals of the San Juan Basin, New Mexico and Colorado, U.S.A.

USGS Publications Warehouse

Clayton, J.L.; Rice, D.D.; Michael, G.E.

1991-01-01

Coal beds of the Upper Cretaceous Fruitland Formation in the San Juan Basin of northwestern New Mexico and southwestern Colorado have significant liquid hydrocarbon generation potential as indicated by typical Rock-Eval Hydrogen Indexes in the range of 200-400 mg hydrocarbon/g organic carbon (type II and III organic matter). Small, non-commercial quantities of oil have been produced from the coal beds at several locations. The oils are characterized by high pristane/phytane (ca 4) and pristane/n-C17 ratios (ca 1.2), abundant C21+ alkanes in the C10+ fraction with a slight predominance of odd carbon-numbered n-alkanes, abundant branched-chain alkanes in the C15+ region, and a predominance of methylcyclohexane in the C4-C10 fraction. The oils are indigenous to the Fruitland Formation coals and probably migrated at thermal maturities corresponding to vitrinite reflectance values in the range 0.7-0.8%. Although the oils found to date are not present in commercial amounts, these findings illustrate the potential of some coals to generate and expel oil under conditions of moderate thermal heating. ?? 1991.

Petrology, mineralogy and geochemistry of mined coals, western Venezuela

USGS Publications Warehouse

Hackley, Paul C.; Warwick, Peter D.; González, Eligio

2005-01-01

Upper Paleocene to middle Miocene coal samples collected from active mines in the western Venezuelan States of Táchira, Mérida and Zulia have been characterized through an integrated geochemical, mineralogical and petrographic investigation. Proximate, ultimate, calorific and forms of sulfur values, major and trace element, vitrinite reflectance, maceral concentrations and mineral matter content have been determined for 16 channel samples from 14 mines. Ash yield generally is low, ranging from < 1 to 17 wt.% (mean = 5 wt.%) on a dry basis (db). Total sulfur content is low to moderate, ranging from 1 to 6 wt.%, db (average = 1.7 wt.%). Calorific value ranges from 25.21 to 37.21 MJ/kg (10,840–16,000 Btu/lb) on a moist, mineral-matter-free basis (average = 33.25 MJ/kg, 14,300 Btu/lb), placing most of the coal samples in the apparent rank classification of high-volatile bituminous. Most of the coal samples exhibit favorable characteristics on the various indices developed to predict combustion and coking behavior and concentrations of possible environmentally sensitive elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, Th and U) generally are similar to the concentrations of these elements in most coals of the world, with one or two exceptions. Concentrations of the liptinite maceral group range from < 1% to 70 vol.%. Five samples contain > 20 vol.% liptinite, dominated by the macerals bituminite and sporinite. Collotelinite dominates the vitrinite group; telinite was observed in quantities of ≤ 1 vol.% despite efforts to better quantify this maceral by etching the sample pellets in potassium permanganate and also by exposure in an oxygen plasma chamber. Inertinite group macerals typically represent < 10 vol.% of the coal samples and the highest concentrations of inertinite macerals are found in distantly spaced (> 400 km) upper Paleocene coal samples from opposite sides of Lago de Maracaibo, possibly indicating tectonic controls on subsidence related to construction of the Andean orogen. Values of maximum reflectance of vitrinite in oil (Ro max) range between 0.42% and 0.85% and generally are consistent with the high-volatile bituminous rank classification obtained through ASTM methods. X-ray diffraction analyses of low-temperature ash residues indicate that kaolinite, quartz, illite and pyrite dominate the inorganic fraction of most samples; plagioclase, potassium feldspar, calcite, siderite, ankerite, marcasite, rutile, anatase and apatite are present in minor or trace concentrations. Semiquantitative values of volume percent pyrite content show a strong correlation with pyritic sulfur and some sulfide-hosted trace element concentrations (As and Hg). This work provides a modern quality dataset for the western Venezuela coal deposits currently being exploited and will serve as the foundation for an ongoing coal quality research program in Venezuela.

Preliminary evaluation of the coalbed methane potential of the Gulf Coastal Plain, USA and Mexico

USGS Publications Warehouse

Warwick, Peter D.; Barker, Charles E.; SanFilipo, John R.; Schwochow, S.D.; Nuccio, V.F.

2002-01-01

Several areas in the Gulf Coast have potential for coalbed gas accumulations. These areas include parts of southern Alabama and Mississippi, north-central Louisiana, northeast, east-central and south Texas and northeastern Mexico. The coal deposits in these areas vary in rank, thickness, lateral extent and gas content, and range in age from Late Cretaceous to Eocene.Gas desorption tests conducted by the U.S. Geological Survey (USGS) on shallow (2,000 ft [609 m]) Paleocene (Wilcox-Midway Groups) coals of southeastern Mississippi indicate that the coalbeds contain some methane. Measured gas contents range from 0 to 19 scf/ton (0.19 to 0.59 cc/g; dry, ash-free) and average about 15 scf/ton (0.5 cc/g). These coals have apparent ranks of lignite to subbituminous (vitrinite reflectance of 0.3 to 0.4% Romax) at shallow depths and subbituminous to bituminous (0.5 to 0.6% Romax) in the deeper parts of the basin. Adsorption isotherm data indicate that Wilcox Group coals are undersaturated and have methane gas-storage capacities similar to those of the subbituminous coals in the Powder River basin, Wyoming. In the primary areas where Wilcox Group coalbeds are mined and subsurface data are available, net coal thickness ranges from about 10 to 50 ft (3 to 15 m), which is much less than coal thickness in the Powder River basin, which can be 300 ft (91 m).Upper Cretaceous and Paleocene-Eocene coals of south Texas and northeastern Mexico are subbituminous to bituminous rank (up to 0.6% Romax). Some methane has been produced commercially from thin coal beds (13 ft [4 m] net) and associated sandstone at shallow depths (

Palynostratigraphy of the Erkovtsy field of brown coal (the Zeya-Bureya sedimentary basin)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kezina, T.V.; Litvinenko, N.D.

2007-08-15

The Erkovtsy brown coal field in the northwestern Zeya-Bureya sedimentary basin (129-130{sup o}E, 46-47{sup o}N) is structurally confined to southern flank of the Mesozoic-Cenozoic Belogor'e depression. The verified stratigraphic scheme of the coalfield sedimentary sequence is substantiated by palynological data on core samples from 18 boreholes sampled in the course of detailed prospecting and by paleobotanical analysis of sections in the Yuzhnyi sector of the coalfield (data of 1998 by M.A. Akhmetiev and S.P. Manchester). Sections of the Erkovtsy, Arkhara-Boguchan, and Raichikha brown-coal mines are correlated. Stratigraphic subdivisions distinguished in the studied sedimentary succession are the middle and upper Tsagayanmore » subformations (the latter incorporating the Kivda Beds), Raichikha, Mukhino, Buzuli, and Sazanka formations.« less

Preliminary thermal-maturity map of the Cameo and Fairfield or equivalent coal zone in the Piceance Creek Basin, Colorado

USGS Publications Warehouse

Nuccio, Vito F.; Johnson, Ronald C.

1983-01-01

This map was prepared in cooperation with the U.S. Department of Energy's Western Gas Sands Project and was constructed to show the thermal maturity of the Upper Cretaceous Mesaverde Formation (or Group) in the Piceance Creek Basin. The ability of a source rock to generate oil and gas is directly related to its kerogen content and thermal maturity; hence, thermal maturity is commonly used as an exploration tool. This publication consists of two parts: a coal rank map for the basinwide Cameo and Fairfield or equivalent coal zone and three cross sections showing the variation in a coal rank for the entire Mesaverde. Structure contours on the map show the top of the Rollins Sandstone Member of the Mesaverde Formation and its equivalent the Trout Creek Sandstone Member of the Iles Formation of the Mesaverde Group, which immediately underlie the Cameo and Fairfield zone. The structure contours show the fairly strong correlation between structure and coal rank in the basin, suggesting that maximum overburden was the key factor in determining the coal ranks. Even in the southern part of the basin where extensive plutonism occurred during the Oligocene, coal ranks still generally follow structure; indicating that the plutons had little affect on the coals. On the cross sections both the top of the Rollins and Trout Creek, and the top of the Mesaverde Formation/Group are shown. A complete analysis of the entire Mesaverde in the basin would require more information than is presently available.

Early paleozoic gabbro-amphibolites in the structure of the Bureya Terrane (eastern part of the Central Asian Fold Belt): First geochronological data and tectonic position

NASA Astrophysics Data System (ADS)

Smirnov, Yu. V.; Sorokin, A. A.; Kudryashov, N. M.

2012-07-01

Resulting from U-Pb geochronological study, it has been found that the gabbro-amphibolites composing the Bureya (Turan) Terrane in the eastern part of the Central Asian Fold Belt are Early Paleozoic (Early Ordovician; 455 ± 1.5 Ma) in age rather than Late Proterozoic as was believed earlier. The gabbro-amphibolites and associated metabasalts are close to tholeiites of the intraoceanic island arcs in terms of the geochemical properties. It is suggested that the tectonic block composed of these rocks was initially a seafloor fragment that divided the Bureya and Argun terranes in the Early Paleozoic and was later tectonically incorporated into the modern structure of the Bureya Terrane as a result of Late Paleozoic and Mesozoic events.

Petrographic And Geochemical Relationships And Environmentally Significant Trace Element Contents Of Miocene Coals in The Çayirli (Erzincan) Area, Eastern Anatolia, Turkey

NASA Astrophysics Data System (ADS)

Yalcin Erik, Nazan

2014-05-01

This study has done related to the petrographic, coal-quality and the environmental influences of the Çayırlı coal field in the Eastern Anatolia. The region is one of the best examples of a continental collision zone in the world and located in a North-south converging collision zone between the Eurasian and the Arabian Plates. The geological units on the North of the basin are the peridotites and on the South, the Upper Triassic to Lower Cretaceous limestone. Tertiary sedimentary units also occupy a significant part of the geological features. Lower Miocene sediments include recifal limestone, marls, green clay and coal seams. The Çayırlı mining area in Eastern Anatolia region, contains these Miocene aged coals. These coals is characterized by high vitrinite and inertinite and low liptinite contents. The coals are Bituminous coal rank, with vitrinite reflectance ranging from 0.53 to 0.58%. Chemically, the coal in this study is characterised by low moisture, ash yield and sulfur content. The Çayırlı coal consist mainly of SiO2 and CaO, with secondary Fe2O3, Al2O3, and minor proportions of TiO2, P2O5 and other oxides. Several trace elements of environmental concern namely As, U and Be in Çayırlı coal are above the world averages, while Ni and Pb concentrations are less than the world average. However, As, Co, Cr, Ni, Pb, U and V contents of this coal are below Turkish averages. It can clearly observed that the concentration of the elements is highest in the high ash coal levels. Among the potentially hazardous trace elements, Be, Co, Ni, Se and U may be of little or no health and environmental concerns, wheras As, Pb, Sb, and Th require further examination for their potential health and environmental concerns. These properties may be related to evaluation of the coal forming environment from more reducing contitions in a marine influenced lower delta plain environment for investigated coals. On the basis of analytical data, there is no possibility that the Çayırlı coals could be used for residential heating or industrial applications; when used, they cause significant of air pollution and healt problems.

Tectono-thermal Evolution of the Lower Paleozoic Petroleum Source Rocks in the Southern Lublin Trough: Implications for Shale Gas Exploration from Maturity Modelling

NASA Astrophysics Data System (ADS)

Botor, Dariusz

2018-03-01

The Lower Paleozoic basins of eastern Poland have recently been the focus of intensive exploration for shale gas. In the Lublin Basin potential unconventional play is related to Lower Silurian source rocks. In order to assess petroleum charge history of these shale gas reservoirs, 1-D maturity modeling has been performed. In the Łopiennik IG-1 well, which is the only well that penetrated Lower Paleozoic strata in the study area, the uniform vitrinite reflectance values within the Paleozoic section are interpreted as being mainly the result of higher heat flow in the Late Carboniferous to Early Permian times and 3500 m thick overburden eroded due to the Variscan inversion. Moreover, our model has been supported by zircon helium and apatite fission track dating. The Lower Paleozoic strata in the study area reached maximum temperature in the Late Carboniferous time. Accomplished tectono-thermal model allowed establishing that petroleum generation in the Lower Silurian source rocks developed mainly in the Devonian - Carboniferous period. Whereas, during Mesozoic burial, hydrocarbon generation processes did not develop again. This has negative influence on potential durability of shale gas reservoirs.

Glacial-eustatic/climatic model for Upper Pennsylvanian marine and nonmarine cyclothems in the Appalachian basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heckel, P.H.

1992-01-01

Only glacial-eustatic sea-level fluctuations can account for all the characteristics of Upper Pennsylvanian marine cyclothems in the Midcontinent. Because this control is global, it must have affected deposition during this time everywhere. In the Appalachian basin widespread well developed paleosols represent long-term sea-level lowstand. During Conemaugh marine incursions, rising sea level ponded fresh-water influx to form peat swamps that migrated landward ahead of transgression and produced early transgressive coals. Marine highstand deposits commonly are conodont-rich limestones, typically skeletal packstone with glaucony and phosphorite. Regression resulted in progradation of detrital shorelines with local delta cycles, followed eventually by more paleosol formationmore » and local erosional incision that removed older sediments including the marine units in places. Fluvial sands filled many of these channels. During Monongahela deposition when marine incursions no longer entered the Appalachian basin, the climatic fluctuations recognized by Cecil can reasonably be related to sea-level fluctuations nearby, but with shifts in climatic significance of gross lithotopes. Coal swamps would more likely have formed at maximum marine highstand when the nearby sea would have provided both high base level and an abundant source of rainfall. Nonmarine limestones would more likely have formed at maximum lowstand when the sea was most distant and the climate driest. The intervening detrital deposits between the coals and limestones formed under intermediate seasonal rainfall regimes during both marine transgression and regression farther west in the Midcontinent. Conemaugh and Allegheny coals without overlying marine units probably also represent mainly marine highstand elsewhere, and nonmarine limestones of these ages typically are associated with lowstand paleosols.« less

30 CFR 785.14 - Mountaintop removal mining.

Code of Federal Regulations, 2011 CFR

2011-07-01

... mountaintop removal mining. (b) Mountaintop removal mining means surface mining activities, where the mining operation removes an entire coal seam or seams running through the upper fraction of a mountain, ridge, or... adjacent land uses; (B) Obtainable according to data regarding expected need and market; (C) Assured of...

Compositional evolution of the upper continental crust through time, as constrained by ancient glacial diamictites

NASA Astrophysics Data System (ADS)

Gaschnig, Richard M.; Rudnick, Roberta L.; McDonough, William F.; Kaufman, Alan J.; Valley, John W.; Hu, Zhaochu; Gao, Shan; Beck, Michelle L.

2016-08-01

The composition of the fine-grained matrix of glacial diamictites from the Mesoarchean, Paleoproterozoic, Neoproterozoic, and Paleozoic, collected from four modern continents, reflects the secular evolution of the average composition of the upper continental crust (UCC). The effects of localized provenance are present in some cases, but distinctive geochemical signatures exist in diamictites of the same age from different localities, suggesting that these are global signatures. Archean UCC, dominated by greenstone basalts and to a lesser extent komatiites, was more mafic, based on major elements and transition metal trace elements. Temporal changes in oxygen isotope ratios, rare earth elements, and high field strength elements indicate that the UCC became more differentiated and that tonalite-trondhjemite-granodiorite suites became less important with time, findings consistent with previous studies. We also document the concentrations of siderophile and chalcophile elements (Ga, Ge, Cd, In, Sn, Sb, W, Tl, Bi) and lithophile Be in the UCC through time, and use the data for the younger diamictites to construct a new estimate of average UCC along with associated uncertainties.

Radiometric ages of the Fire Clay tonstein [Pennsylvanian (Upper Carboniferous), Westphalian, Duckmantian]: A comparison of U-Pb zircon single-crystal ages and 40Ar/39Ar sanidine single-crystal plateau ages

USGS Publications Warehouse

Lyons, P.C.; Krogh, T.E.; Kwok, Y.Y.; Davis, D.W.; Outerbridge, W.F.; Evans, H.T.

2006-01-01

The Fire Clay tonstein [Pennsylvanian (Upper Carboniferous), Westphalian Series, Duckmantian Stage]-a kaolinized, volcanic-ash deposit occurring in Kentucky, West Virginia, Tennessee, and Virginia-is the most widespread bed in the Middle Pennsylvanian of the central Appalachian basin, USA. A concordant single-crystal U-Pb zircon datum for this tonstein gives a 206Pb/238U age of 314.6 ?? 0.9 Ma (2??). This age is in approximate agreement with a mean sanidine plateau age of 311.5 ?? 1.3 Ma (1??, n = 11) for the Fire Clay tonstein. The difference between the two ages may be due to bias between the 40K and 238U decay constants and other factors. The age of the Fire Clay tonstein has important implications for Duckmantian Stage (Westphalian Series) sedimentation rates, correlations with the Westphalian Series of Europe, Middle Pennsylvanian volcanic events, and the late Paleozoic time scale. ?? 2006 Elsevier B.V. All rights reserved.

Geologic characterization report for the Paradox Basin Study Region, Utah Study Areas. Volume 6: Salt Valley

NASA Astrophysics Data System (ADS)

1984-12-01

Surface landforms in the Salt Valley Area are generally a function of the Salt Valley anticline and are characterized by parallel and subparallel cuestaform ridges and hogbacks and flat valley floors. The most prominent structure in the Area is the Salt Valley anticline. Erosion resulting from the Tertiary uplift of the Colorado Plateau led to salt dissolution and subsequent collapse along the crest of the anticline. Continued erosion removed the collapse material, forming an axial valley along the crest of the anticline. Paleozoic rocks beneath the salt bearing Paradox Formation consist of limestone, dolomite, sandstone, siltstone and shale. The salt beds of the Paradox formation occur in distinct cycles separated by an interbed sequence of anhydrite, carbonate, and clastic rocks. The Paradox Formation is overlain by Pennsylvanian limestone; Permian sandstone; and Mesozoic sandstone, mudstone, conglomerate and shale. No earthquakes have been reported in the area during the period of the historic record and contemporary seismicity appears to be diffusely distributed, of low level and small magnitude. The upper unit includes the Permian strata and upper Honaker trail formation.

Fishes and tetrapods in the upper pennsylvanian (kasimovian) cohn coal member of the mattoon formation of illinois, United States: Systematics, paleoecology, and paleoenvironments

USGS Publications Warehouse

Carpenter, D.; Falcon-Lang, H. J.; Benton, M.J.; Nelson, W.J.

2011-01-01

A newly discovered vertebrate assemblage is reported from the Upper Pennsylvanian (mid-to upper Kasimovian) Cohn Coal Member of the Mattoon Formation of southeast Illinois, United States. Teeth, scales, and spines of xenacanth (Dicentrodus, Orthacanthus, Triodus, Xenacanthus) and euselachian (Sphenacanthus) sharks dominate the assemblage. Less common are the teeth, scales, and centra of holocephalan (Helodus) and actinopterygian fishes, together with rare tetrapod (mainly pelycosaur) phalanges and centra. The assemblage occurs within a broad, shallow channel incised into a prominent Vertisol. The channel is interpreted as having been cut during a seasonally dry glacial phase when sea level was low, but filled during a subsequent transgression triggered by deglaciation. We interpret this as a brackish water (estuarine) assemblage, based on the co-occurrence of the vertebrate material with spirorbids (putative microconchids) and paleoecological inferences gleaned from a critical analysis of the literature dealing with Pennsylvanian fish ecology. This interpretation is broadly consistent with taphonomic data and the results of 87Sr/86Sr isotope analysis of shark material. The pelycosaur material may have been reworked from the lowstand Vertisol, however, and these animals occupied dryland niches that developed during glacial phases. ?? 2011 SEPM (Society for Sedimentary Geology).

Shifting locus of carbonate sedimentation and the trajectory of Paleozoic pCO2

NASA Astrophysics Data System (ADS)

Husson, J. M.; Peters, S. E.

2016-12-01

The burial of calcium carbonate is a determinant of planetary habitability, dictated by CO2 input to the surface environment and rates of chemical weathering. An important source of CO2 is the metamorphism of carbon-bearing sediments, which is responsive to the locus of sedimentation. For example, deep sea sediments are prone to recycling as sea floor is consumed at convergent margins; by contrast, sediments deposited on continental crust can be stable for billions of years.The predominant feature in the empirical sedimentary rock record, as measured by Macrostrat (https://macrostrat.org) and global geological syntheses, is a step-wise increase in continental sedimentation at the Neoproterozoic-Paleozoic transition. Although early Paleozoic carbonate volumes are sufficient to account for a CO2 flux 5x greater than present, Proterozoic continental burial fluxes were likely below the modern estimate. This observation implies that most carbonate sedimentation in the Proterozoic took place on the deep sea floor. The establishment of persistent, widespread continental flooding during the Paleozoic shifted the locus of carbonate sedimentation to continental interiors. A major implication of this shift is that CO2 flux declined during the Paleozoic as carbonate-laden Precambrian seafloor was metamorphosed and recycled. This prediction is consistent with independent proxy records and our model for Phanerozoic carbonate burial. An important corollary is that as carbonate-rich Precambrian seafloor was progressively destroyed, the carbonate content of deep sea sediments decreased concordantly because Paleozoic continents effectively captured global alkalinity fluxes. This process culminated near the Permian/Triassic, with metamorphic CO2 flux at a Phanerozoic minimum and the global ocean uniquely unbuffered against acidification. Such a condition could enhance the environmental effects of transient CO2 injections. Because the mid-Mesozoic appearance of pelagic calcifiers and Cenozoic fall in continental flooding reestablished a deep sea carbonate sink, the Paleozoic was a unique time in Earth history when the continents were the only major, quantitatively important locus of carbonate burial.

Early Paleozoic tectonics for the New Siberian Islands terrane (Eastern Arctic)

NASA Astrophysics Data System (ADS)

Metelkin, D. V.; Chernova, A. I.; Vernikovsky, V. A.; Matushkin, N. Yu.

2017-11-01

The New Siberian Islands archipelago is one of the few research objects accessible for direct study on the eastern Arctic shelf. There are several models that have different interpretations of the Paleozoic tectonic history and the structural affinity of the New Siberian Islands terrane. Some infer a direct relationship with the passive continental margin of the Siberian paleocontinent. Others connect it with the marginal basins of Baltica and Laurentia, or the Chukotka-Alaska microplate. Our paleomagnetic investigation led us to create an apparent polar wander path for the early Paleozoic interval of geological history. Based on it we can conclude that the New Siberian Islands terrane could not have been a part of these continental plates. This study considers the possible tectonic scenarios of the Paleozoic history of the Earth, presents and discusses the corresponding global reconstructions describing the paleogeography and probable mutual kinematics of the terranes of the Eastern Arctic.

Archean inheritance in zircon from late Paleozoic granites from the Avalon zone of southeastern New England: an African connection

USGS Publications Warehouse

Zartman, R.E.; Don, Hermes O.

1987-01-01

In southeastern New England the Narragansett Pier Granite locally intrudes Carboniferous metasedimentary rocks of the Narragansett basin, and yields a monazite UPb Permian emplacement age of 273 ?? 2 Ma. Zircon from the Narragansett Pier Granite contains a minor but detectable amount of an older, inherited component, and shows modern loss of lead. Zircon from the late-stage, aplitic Westerly Granite exhibits a more pronounced lead inheritance -permitting the inherited component to be identified as Late Archean. Such old relict zircon has not been previously recognized in Proterozoic to Paleozoic igneous rocks in New England, and may be restricted to late Paleozoic rocks of the Avalon zone. We suggest that the Archean crustal component reflects an African connection, in which old Archean crust was underplated to the Avalon zone microplate in the late Paleozoic during collision of Gondwanaland with Avalonia. ?? 1987.

The 1997 core drilling through Ordovician and Silurian strata at Röstånga, S. Sweden: preliminary stratigraphic assessment and regional comparison

USGS Publications Warehouse

Bergstrom, Stig M.; Huff, W.D.; Koren', T.; Larsson, K.; Ahlberg, P.; Kolata, Dennis R.

1999-01-01

A core drilling at Ro??sta??nga, the first such drilling ever undertaken in this classical Lower Paleozoic outcrop area in W-central Scania, penetrated an approximately 96 m thick succession of Lower Silurian-upper Middle Ordovician marine rocks. The drilling was stopped at a depth of 132.59 m in an interval of crushed rocks, probably a prominent fault zone, that proved impossible to drill through. The core contains a stratigraphical sequence from the basal Upper Llandoverian (Telychian Stage) to the upper Middle Ordovician (Harjuan Stage). The following units are recognized in descending stratigraphic order (approximate thickness in parenthesis): Kallholn Formation (35 m), Lindega??rd Mudstone (27 m), Fja??cka Shale (13 m), Mossen Formation (0.75 m), Skagen Formation (2.5 m), and Sularp Shale (19 m+). Except for the Skagen Formation, the drilled sequence consists of shales and mudstones with occasional thin limestone interbeds and is similar to coeval successions elsewhere in Scania. There are 11 K-bentonite beds in the Kallholn Formation, 2(3?) in the Lindega??rd Mudstone, 1 in the Mossen Formation, 7 in the Skagen Formation, and 33 in the Sularp Shale. The core serves as an excellent Lower Silurian-upper Middle Ordovician reference standard not only for the Ro??sta??nga area but also for southernmost Sweden in general because the cored sequence is the stratigraphically most complete one known anywhere in this region.

Evolution of the Alpine Tethys (Sava) suture zone in Fruška Gora Mountains (N Serbia): from orogenic building to tectonic omissions

NASA Astrophysics Data System (ADS)

Toljić, Marinko; Matenco, Liviu; ĐErić, Nevenka; Milivojević, Jelena; Gerzina, Nataša.; Stojadinović, Uros

2010-05-01

The Fru\\vska Gora Mountains in northern Serbia offers an unique opportunity to study the Cretaceous-Eocene evolution of the NE part of the Dinarides, which is largely covered elsewhere beneath the thick Miocene sediments of the Pannonian basin, deposited during the back-arc collapse associated with the subduction and roll-back recorded in the external Carpathians. The structural grain of the Fru\\vska Gora Mountains is the one of a large scale antiform, exposing a complex puzzle of highly deformed metamorphic rocks in its centre and Triassic-Miocene sequence of non-metamorphosed sediments, ophiolites and volcanics along its flanks. The metamorphic rocks were the target of structural investigations coupled with paleontological dating (conodonts, palynomorphs and radiolarians) in an effort to unravel the geodynamic evolution of an area thought to be located near the suture zone between the Tisza upper plate and the Adriatic lower plate, i.e. the Sava subduction zone of the Dinarides (e.g., Pamic, 2002; Schmid et al., 2008). The existence of this subduction zone was previously inferred here by local observations, such as metamorphosed Mesozoic sediments containing Middle Triassic conodonts (Đurđanović, 1971) or Early Cretaceous blue schists metamorphism (123±5 Ma, Milovanović et al., 1995). The metamorphic sequence is characterized by a Paleozoic age meta-sedimentary basement which contains palynomorphs of Upper Paleozoic - Carboniferous age and a meta-sedimentary and meta-volcanic sequence which contain a succession of contrasting metamorphosed lithologies such sandstones, black limestones, shallow water white limestones, basic volcanic sequences, deep nodular limestiones, radiolarites, meta-ophiolites and turbiditic sequences. The lower part of the sequence is contrastingly similar with the Triassic cover of the Drina-Ivanijca thrust sheet and its metamorphosed equivalent observed in the Kopaonik and Studenica series (Schefer et al., in press). This observation is supported by the newly found micro-fauna of Upper Triassic in age in the meta-sandstones associated with meta-volcanics on the SW slopes of the mountain. The upper part of the sequence display metamorphosed "flysh"-type of sequences and meta-basalts. In these deposits, slightly metamorphosed siliciclastics (lithic sandstones with volcanic-derived clasts) previously interpreted as Upper Jurassic mélange have proved to contain Upper Cretaceous palynomorphs. Among the rocks exposed in the metamorphic core of the mountains, the SW slope of Fru\\vska Gora offers the optimal locality for the study of the kinematic evolution. Here, four phases of folding have been mapped, being associated mainly with large-scale regional contraction. The first phase is characterized by isoclinal folding, with reconstructed SW vergence. The second generation of E-W oriented and coaxial folds is asymmetric and is up to metres in size, displaying a south vergence and has largely refolded the previous generation. The third event was responsible for the formation of upright folds, yet again E-W oriented, re-folding earlier structures. The first two phases of folding are associated with metamorphic conditions, while the third was apparently near the transition with the brittle domain. The relationship with a fourth folding event observed also in the non-metamorphosed clastic-carbonate rocks is rather uncertain, but is apparently associated with the present day antiformal structure of the Fuska Gora Mountains. Interestingly, the metamorphosed Triassic and Upper Cretaceous carbonatic-clastic sequence in the core of the antiform is in structural contact along the antiformal flanks with Lower-Middle Triassic and Upper Cretaceous-Paleogene sediments which display the same facies, but these are not metamorphosed. This demonstrates a large scale tectonic omission along the flanks of the Fru\\vska Gora antiform, 9-10km of rocks being removed by what we speculatively define as an extensional detachment exhuming the metamorphic core. This detachment has been subsequently folded into the present-day antiformal geometry of the Fru\\vska Gora Mountains. These findings demonstrate that the metamorphic and non-metamorphic Upper Cretaceous - Paleogene clastic-carbonate sediments belongs to the main Alpine Tethys (Sava) subduction zone of the Dinarides. The Paleozoic-Triassic metamorphic and non-metamorphic rocks belong to the distal Adriatic lower plate, or more precisely to the Jadar-Kopaonik composite thrust sheet (Schmid et al., 2008), while the layer of serpentinized peridotite found at their contact most probably belongs to the Western Vardar ophiolites obducted over the Adriatic plate during Late Jurassic - Earliest Cretaceous. The distal Jadar-Kopaonik composite unit was partly affected by strong contractional deformation and a Late Eocene greenschist facies metamorphism during the main phase of subduction and collision, similarly to what has been observed elsewhere in the Dinarides (Pamić, 2002; Schefer et al., in press). A Miocene phase of core-complex formation was responsible for the large tectonic omission observed, being probably followed by the formation of a wide open antiformal structure during the Pliocene-Quaternary inversion of the Pannonian basin.

Structure and Evolution of the Central Andes of Peru

NASA Astrophysics Data System (ADS)

Gonzalez, L.; Pfiffner, O. A.

2009-04-01

Three major units make up the Andes in Peru: (1) The Western Cordillera consists of the Cretaceous Coastal Batholith intruding Jurassic to Cretaceous volcaniclastics (Casma group) in the west, and a fold-and-thrust belt of Mesozoic sediments in the east. Eocene and Miocene volcanics (Calipuy group and equivalents) overly all of these rock types. (2) The Central Highland contains a folded Paleozoic-Mesozoic sedimentary sequence overlain by thick Quaternary deposits. A major fault puts Neoproterozoic basement rocks of the Eastern Cordillera next to these units. (3) In the Eastern Cordillera, Late Paleozoic clastic successions unconformably overly folded Early Paleozoic sediments and a Neoproterozoic basement in the east. Permian (locally Triassic) granitoids intruded these units and were affected by folding and thrusting. In the core of the Eastern Cordillera, Early Cretaceous overly Early or Late Paleozoic strata. To the west, a thrust belt of Paleozoic to Cenozoic strata forms the transition to the foreland of the Brasilian shield. The most external part of this thrust belt involves Pliocene sediments and is referred to as Subandine zone. The Coastal Batholith is internally undeformed. The adjacent fold-and-thrust belt to the east is characterized by tight, nearly isoclinal upright folds with amplitudes of up to 1000 m. At the surface only Cretaceous rocks are observed. Using balancing techniques, a detachment horizon at the base of the Lowermost Cretaceous (Goyallarisquizga group - Oyon Formation) can be proposed. Further east, folds are more open, asymmetric and east verging, Jurassic sediments appear in the cores of the anticlines. The abrupt change in style from upright tight folding in the west to more open folding in the east is explained by a primary difference in the depositional sequence, most probably associated with synsedimentary faulting. The overlying volcanics of the Calipuy group and equivalents are, in turn, only slightly folded. In the Northern part of the Western Cordillera, near Huaraz, a vertical fault puts a Late Miocene to Early Pliocene batholith (Cordillera Blanca) in direct contact to Miocene volcanics (Calipuy group, Cordillera Negra). The structure of the Central Highlands is characterized by relatively open folds in the Paleozoic to Mesozoic strata. Overlying Quaternary deposits are tilted and locally even folded. Eocene to Miocene undeformed granitoids intrude these structures. A swarm of NNW-SSE striking and steeply dipping faults separate the Eastern Cordillera from the Highlands. Some of these faults suggest block faulting. However, near Huancayo a clear indication of strike-slip motion could be found. The Neoproterozoic basement rocks and the Early Paleozoic sediments are unconformably overlain by Late Paleozoic sediments which in turn are folded. Within the Subandine zone, the structural style is characterized by east directed imbricate thrusting. The thrust faults cut down into the crystalline basement going west, suggesting a detachment within upper crustal crystalline basement rocks. In the Central Peruvian Andes, compressional deformation events progressed from west to east. Early Cretaceous plutons of the coast batholith intruded folded Jurassic to Early Cretaceous volcaniclastic rocks of the Casma group and suggest an Early Cretaceous phase of shortening in the Pacific coastal area of the Western Cordillera (referred to as Mochica phase in the literature). Within the Western Cordillera, a major phase of pre-Eocene erosion removed a substantial amount of the tight upright folds. The youngest strata folded are of Late Cretaceous to Early Paleocene age (Red Beds). The overlying volcanics are slightly younger (middle Eocene) and bracket the tight folding, referred to as Inca phase, to Late Paleocene to Early Eocene times. This is corroborated by Eocene to Miocene granitic intrusions in the adjacent fold-and-thrust belt. Still younger deformations, referred to as Quechua Phase, produced gentle folds within the Eocene volcanics. Vertical motions in the Cordillera Blanca juxtaposed a Late Miocene-Pliocene batholith to Late Miocene volcanics. These movements are post-Pleistonce in age and still active. In the Central High Zone, even Pleistocene deposits were tilted and locally folded. Timing of the steeply dipping faults bordering the Eastern Cordillera is more difficult to assess. Cretaceous strata in tectonic contact with Neoproterozoic basement indicate a Cenozoic age. But within the fold-and-thrust belt of the Subandine zone in the east, youngest strata affected by thrusting are progressively younger toward the east. They suggest thrust propagation ranging from Oligocene to Pliocene age. These young thrust faults were responsible for the uplift of the Central Highland to their present elevation.

Chemical quality of surface water in the Allegheny River basin, Pennsylvania and New York

USGS Publications Warehouse

McCarren, Edward F.

1967-01-01

The Allegheny River is the principal source of water to many industries and to communities in the upper Ohio River Valley. The river and its many tributaries pass through 19 counties in northwestern and western Pennsylvania. The population in these counties exceeds 3 million. A major user of the Allegheny River is the city of Pittsburgh, which has a population greater than The Allegheny River is as basic to the economy of the upper Ohio River Valley in western Pennsylvania as are the rich deposits of bituminous coal, gas, and oil that underlie the drainage basin. During the past 5 years many streams that flow into the Allegheny have been low flowing because of droughts affecting much of the eastern United States. Consequently, the concentration of solutes in some streams has been unusually high because of wastes from coal mines and oil wells. These and other water-quality problems in the Allegheny River drainage basin are affecting the economic future of some areas in western Pennsylvania. Because of environmental factors such as climate, geology, and land and water uses, surface-water quality varies considerably throughout the river basin. The natural quality of headwater streams, for example, is affected by saltwater wastes from petroleum production. One of the streams most affected is Kinzua Creek, which had 2,900 parts per million chloride in a sample taken at Westline on September 2, 1959. However, after such streams as the Conewango, Brokenstraw, Tionesta, Oil, and French Creeks merge with the Allegheny River, the dissolved-solids and chloride concentrations are reduced by dilution. Central segments of the main river receive water from the Clarion River, Redbank, Mahoning, and Crooked Creeks after they have crossed the coal fields of west-central Pennsylvania. At times, therefore, these streams carry coal-mine wastes that are acidic. The Kiskiminetas River, which crosses these coal fields, discharged sulfuric acid into the Allegheny at a rate of 299 tons a day during the 1962 water year (October 1, 1961, to September 30, 1962). Mine water affects the quality of the Allegheny River most noticeably in its lower part where large withdrawals are made by the Pittsburgh Water Company at Aspinwall and the Wilkinsburg-Penn Joint Water Authority at Nadine. At these places raw river water is chemically .treated in modern treatment plants to control such objectionable characteristics as acidity and excessive concentrations of iron and manganese. Dissolved-solids content in the river varies along its entire length. In its upper reaches the water of the Allegheny River is a sodium chloride type, and at low flow, the sodium chloride is more than half the dissolved solids. In its lower reaches the water is a calcium sulfate .type, and at low flow the calcium sulfate is more than half the dissolved solids. In middle segments of the river from Franklin to Kittanning, water is more dilute and of a mixed type. Many small and several larger streams in the upper basin--such as the Conewango, Brokenstraw, Kinzua, Tionesta, and French Creeks--support large populations of game-fish. Even in segments of the Clarion River, Mahoning, and Redbank Creeks, which are at times affected by coal-mine wastes, fish are present. Although different species withstand varying amounts of contaminants in water, the continued presence of the fish indicates that the water is relatively pure and suitable for recreation and many other uses.

Integrated interpretation of geophysical data of the Paleozoic structure in the northwestern part of the Siljan Ring impact crater, central Sweden

NASA Astrophysics Data System (ADS)

Muhamad, Harbe; Juhlin, Christopher; Malehmir, Alireza; Sopher, Daniel

2018-01-01

The Siljan Ring impact structure is the largest known impact structure in Europe and is Late Devonian in age. It contains a central uplift that is about 20-30 km in diameter and is surrounded by a ring-shaped depression. The Siljan area is one of the few areas in Sweden where the Paleozoic sequence has not been completely eroded, making it an important location for investigation of the geological and tectonic history of Baltica during the Paleozoic. The Paleozoic strata in this area also provide insight into the complex deformation processes associated with the impact. In this study we focus on the northwestern part of the Siljan Ring, close to the town of Orsa, with the main objective of characterizing the subsurface Paleozoic succession and uppermost Precambrian crystalline rocks along a series of seismic reflection profiles, some of which have not previously been published. We combine these seismic data with gravity and magnetic data and seismic traveltime tomography results to produce an integrated interpretation of the subsurface in the area. Our interpretation shows that the Paleozoic sequence in this area is of a relatively constant thickness, with a total thickness typically between 300 and 500 m. Faulting appears to be predominantly extensional, which we interpret to have occurred during the modification stage of the impact. Furthermore, based on the geophysical data in this area, we interpret that the impact related deformation to differ in magnitude and style from other parts of the Siljan Ring.

5. OBLIQUE VIEW OF HOIST, SHOWING REDUCTION GEARS AND BED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. OBLIQUE VIEW OF HOIST, SHOWING REDUCTION GEARS AND BED FOR (MISSING) CLUTCH/DRIVE GEAR UNIT, LOOKING EAST (McNALLY DRYER AND COVER SHOWN IN EXTREME UPPER RIGHT BACKGROUND) - Buffalo Coal Mine, Vulcan Cable Hoist, Wishbone Hill, Southeast end, near Moose Creek, Sutton, Matanuska-Susitna Borough, AK

Principal reference section for part of the Eocene Ghazij Formation, Moghal Mine area, Mach coal field, Balochistan, Pakistan

USGS Publications Warehouse

Johnson, Edward A.; Warwick, Peter D.; Khan, Intizar H.; Kazim, Mohsin A.

1994-01-01

The information presented on this sheet was collected as part of a joint U.S. Geological Survey-Geological Survey of Pakistan program sponsored by the U.S. Agency for International Development. As a project within this program, the coal-bearing Ghazij Formation (Eocene) was investigated in the northeastern part of Balochistan cast and south of the provincial capital of Quetta. Strata exposed in this area range in age from Permian to Holocene and crop out as a belt of folded and thrusted rocks that form a southeast-facing orocline. In this region of Pakistan, the Ghazij can usually be divided into three parts. The lower part is the thickest (probably more than 1,000 m) and consists of gray-weathering calcareous mudrock (shale, mudstone, and impure claystone) and a few tabular bodies of fine-to medium-grained calcareous sandstone. The middle part (27-300 m) consists of gray-weathering calcareous mudrock and tabular to lenticular bodies of fine-to medium-grained calcareous sandstone; beds of carbonaceous shale and coal are common. The upper part (as thick as 533 m) contains reddish-weathering calcareous mudrock that contains scattered lenticular bodies of fine- to medium-grained calcareous sandstone. Fossil plant debris is common in mudrock of the lower and middle parts of the Ghazij, and bivalves and gastropods are common in the middle part; the upper part of the Ghazij is usually unfossiliferous. This three-fold division of the Ghazij is less distinct in the Johan area. Here, the upper part of the formation is clearly identifiable, but rocks below it are poorly exposed and assigning a stratigraphic level that separates the middle and lower parts of the formation is problematic. Below the upper part of the formation is a thick sequence of greenish-gray calcareous mudrock that contains locally abundant plant debris and isolated bodies of brown-weathering sandstone. Rare carbonaceous shale and even rarer coal are present in the upper part of this sequence, and this interval of the formation might correspond to the middle part of the Ghazji exposed in areas to the north. We propose that, in the Johan area, those rocks below the upper part of the formation be referred to as the main body of the Ghazij (for example, main-body Ghazij). Underlying the Ghazij are the carbonate rocks of the Paleocene Dungan Formation (or its equivalent), and overlying the Ghazij are the mostly carbonate rocks of the Eocene Kirthar Formation (or its equivalent). Both contacts can be conformable or unconformable. All of the pre-Neogene rocks in Balochistan are greatly deformed by the collision of India and Asia. The Ghazij is especially susceptible to regional compressional tectonics because it contains a large amount of shale and is sandwiched between two thick carbonate units. As a result, bedding-plane faults and isoclinal folds are common.As part of our study of the Ghazij Formation, five stratigraphic sections were measured: one near Pir Ismail Ziarat, one in the Sor Range, two in the vicinity of Mach, and one near Johan. Each area's section is published separately.

Principal reference section for part of the Eocene Ghazij Formation, Sarawan River area, Johan coal field, Balochistan, Pakistan

USGS Publications Warehouse

Johnson, Edward A.; Warwick, Peter D.; Khan, Intizar H.; Rana, Asif N.; Kazim, Mohsin A.

1994-01-01

The information presented on this sheet was collected as part of a joint U.S. Geological Survey-Geological Survey of Pakistan program sponsored by the U.S. Agency for International Development. As a project within this program, the coal-bearing Ghazij Formation (Eocene) was investigated in the northeastern part of Balochistan cast and south of the provincial capital of Quetta. Strata exposed in this area range in age from Permian to Holocene and crop out as a belt of folded and thrusted rocks that form a southeast-facing orocline. In this region of Pakistan, the Ghazij can usually be divided into three parts. The lower part is the thickest (probably more than 1,000 m) and consists of gray-weathering calcareous mudrock (shale, mudstone, and impure claystone) and a few tabular bodies of fine-to medium-grained calcareous sandstone. The middle part (27-300 m) consists of gray-weathering calcareous mudrock and tabular to lenticular bodies of fine-to medium-grained calcareous sandstone; beds of carbonaceous shale and coal are common. The upper part (as thick as 533 m) contains reddish-weathering calcareous mudrock that contains scattered lenticular bodies of fine- to medium-grained calcareous sandstone. Fossil plant debris is common in mudrock of the lower and middle parts of the Ghazij, and bivalves and gastropods are common in the middle part; the upper part of the Ghazij is usually unfossiliferous. This three-fold division of the Ghazij is less distinct in the Johan area. Here, the upper part of the formation is clearly identifiable, but rocks below it are poorly exposed and assigning a stratigraphic level that separates the middle and lower parts of the formation is problematic. Below the upper part of the formation is a thick sequence of greenish-gray calcareous mudrock that contains locally abundant plant debris and isolated bodies of brown-weathering sandstone. Rare carbonaceous shale and even rarer coal are present in the upper part of this sequence, and this interval of the formation might correspond to the middle part of the Ghazji exposed in areas to the north. We propose that, in the Johan area, those rocks below the upper part of the formation be referred to as the main body of the Ghazij (for example, main-body Ghazij). Underlying the Ghazij are the carbonate rocks of the Paleocene Dungan Formation (or its equivalent), and overlying the Ghazij are the mostly carbonate rocks of the Eocene Kirthar Formation (or its equivalent). Both contacts can be conformable or unconformable. All of the pre-Neogene rocks in Balochistan are greatly deformed by the collision of India and Asia. The Ghazij is especially susceptible to regional compressional tectonics because it contains a large amount of shale and is sandwiched between two thick carbonate units. As a result, bedding-plane faults and isoclinal folds are common. As part of our study of the Ghazij Formation, five stratigraphic sections were measured: one near Pir Ismail Ziarat, one in the Sor Range, two in the vicinity of Mach, and one near Johan. Each area's section is published separately.

The Method of Validity Evaluation of Hard Coal Excavation in Residual Seam Parts

NASA Astrophysics Data System (ADS)

Wodarski, Krzysztof; Bijańska, Jolanta; Gumiński, Adam

2017-12-01

The excavation of residual seam parts should be justified by positive assessment of the purposefulness, technical feasibility and economic effectiveness. The results of the profitability evaluation are crucial in a decision making process. The excavation of residual seam parts, even if it is possible from a technical point of view, should not be implemented if it is economically inefficient or when accompanied by a very high risk of non-recovery of invested capital resources. The article presents the evaluation method of possibilities of excavating hard coal from residual seam parts, and the example of its use in one of collieries in the Upper Silesian Coal Basin. Working in line with the developed method, allows to indicate the variant of residual seam part exploitation, which is feasible to implement from a technical point of view, and which is characterized by the highest economic effectiveness and lowest risk.

Longwall Guidance and Control Development

NASA Technical Reports Server (NTRS)

1982-01-01

The longwall guidance and control (G&C) system was evaluated to determine which systems and subsystems lent themselves to automatic control in the mining of coal. The upper coal/shale interface was identified as the reference for a vertical G&C system, with two sensors (the natural backgound and the sensitized pick) being used to locate and track this boundary. In order to insure a relatively smooth recession surface (roof and floor of the excavated seam), a last and present cut measuring instrument (acoustic sensor) was used. Potentiometers were used to measure elevations of the shearer arms. The intergration of these components comprised the vertical control system (pitch control). Yaw and roll control were incorporated into a face alignment system which was designed to keep the coal face normal to its external boundaries. Numerous tests, in the laboratory and in the field, have confirmed the feasibility of automatic horizon control, as well as determining the face alignment.

Palynological correlation of Atokan and lower desmoinesian (Pennsylvanian) strata between the Illinois basin and the Forest City basin in Eastern Kansas

USGS Publications Warehouse

Peppers, R.A.; Brady, L.L.

2007-01-01

Palynological correlation is made between Atokan and lower Desmoinesian strata in the Illinois basin an the Forest City basin in eastern Kansas. Spore data from previous studies of coals in the Illinois basin and other coal basins are compared with data from spore assemblages in coal and carbonaceous shale bands in a core drilled in Leavenworth County, Kansas. Correlations are based on first and/or last occurrences of 31 species common to the Illinois basin and eastern Kansas and on significant increases or decreases in abundance of several of those taxa. The oldest coal, which is 26 ft (8 m) above the top of the Mississippian, is early Atokan (early Westphalian B) in age and is approximately equivalent to the Bell coal bed in the Illinois basin. The Riverton coal bed at the top of the studied interval in Kansas is early Desmoinesian (early Westphalian D) and correlates with about the Lewisport coal bed in the Illinois basin. Three coal beds near the base of the Pennsylvanian in three cores drilled in Cherokee County, Kansas, which were also studied, range in age from late Atokan to early Desmoinesian. As in other coal basins, Lycospora, borne by lycopod trees, greatly dominates the lower and middle Atokan spore assemblages in coals and shale, but spores from ferns, especially tree ferns, significantly increase in abundance in the upper Atokan and lower Desmoinesian. The pattern of change of dominance among Lycosporapellucida, L. granulata, and L, micropapillata in middle Atokan (Westphalian B-C transition) that has been demonstrated earlier in the Illinois basin and eastern Kentucky and Tennessee, also occurs in eastern Kansas. At least 10 species of spores, which appeared in the middle Atokan in other parts of the equatorial coal belt, also appeared at this time in eastern Kansas. Most of these species have their affinities with the ferns, which were adapted to drier habitats than lycopods. Thus, the climate may have become a little drier in the equatorial coal belt during middle Atokan.

A pollution history of Chesapeake Bay

USGS Publications Warehouse

Goldberg, E.D.; Hodge, V.; Koide, M.; Griffin, J.; Gamble, E.; Bricker, O.P.; Matisoff, G.; Holdren, G.R.; Braun, R.

1978-01-01

Present day anthropogenic fluxes of some heavy metals to central Chesapeake Bay appear to be intermediate to those of the southern California coastal region and those of Narragansett Bay. The natural fluxes, however, are in general higher. On the bases of Pb-210 and Pu-239 + 240 geochronologies and of the time changes in interstitial water compositions, there is a mixing of the upper 30 or so centimeters of the sediments in the mid-Chesapeake Bay area through bioturbation by burrowing mollusks and polychaetes. Coal, coke and charcoal levels reach one percent or more by dry weight in the deposits, primarily as a consequence of coal mining operations. ?? 1978.

Studies on a middle Pennsylvanian compression-impression flora from the overburden of the Herrin (No. 6) coal at Carterville, Illinois

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gastaldo, R.A.

1978-01-01

An authigenically cemented flora from the overburden of the Herrin (No. 6) Coal at Carterville, Illinois has yielded a diverse plant assemblage. Twenty-seven genera and fifty-five species are recognized, of which four taxa are described as new. The dominant component is pteridophyte foliage of Pecopteris Brongniart. The floral assemblage is representative of the Middle Pennsylvanian of North America due to an abundance of Upper Allegheny forms, and representative of the Lower Conemaugh (Stephanian). The flora is equated to Zone 10 of Read and Mamay, and the Westphalian D of Europe.

Moho depth model for the Central Asian Orogenic Belt from satellite gravity gradients

NASA Astrophysics Data System (ADS)

Guy, Alexandra; Holzrichter, Nils; Ebbing, Jörg

2017-09-01

The main purpose of this study is to construct a new 3-D model of the Central Asian Orogenic Belt (CAOB) crust, which can be used as a starting point for future lithospheric studies. The CAOB is a Paleozoic accretionary orogen surrounded by the Siberian Craton to the north and the North China and Tarim Cratons to the south. This area is of great interest due to its enigmatic and still not completely understood geodynamic evolution. First, we estimate an initial crustal thickness by inversion of the vertical gravity component of the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) and DTU10 models. Second, 3-D forward modeling of the GOCE gravity gradients is performed, which determines the topography of the Moho, the geometry, and the density distribution of the deeper parts of the CAOB and its surroundings, taking into account the lateral and vertical density variations of the crust. The model is constrained by seismic refraction, reflection, and receiver function studies and geological studies. In addition, we discuss the isostatic implications of the differences between the seismic Moho and the resulting 3-D gravity Moho, complemented by the analysis of the lithostatic load distribution at the upper mantle level. Finally, the correlation between the contrasting tectonic domains and the thickness of the crust reveals the inheritance of Paleozoic and Mesozoic geodynamics, particularly the magmatic provinces and the orocline which preserve their crustal features.

Geologic Map of Baranof Island, southeastern Alaska

USGS Publications Warehouse

Karl, Susan M.; Haeussler, Peter J.; Himmelberg, Glen R.; Zumsteg, Cathy L.; Layer, Paul W.; Friedman, Richard M.; Roeske, Sarah M.; Snee, Lawrence W.

2015-01-01

This map updates the geology of Baranof Island based on fieldwork, petrographic analyses, paleontologic ages, and isotopic ages. These new data provide constraints on depositional and metamorphic ages of lithostratigraphic rock units and the timing of structures that separate them. Kinematic analyses and thermobarometric calculations provide insights on the regional tectonic processes that affected the rocks on Baranof Island. The rocks on Baranof Island are components of a Paleozoic to Early Tertiary oceanic volcanic arc complex, including sedimentary and volcanic rocks that were deposited on and adjacent to the arc complex, deformed, and accreted. The arc complex consists of greenschist to amphibolite facies Paleozoic metavolcanic and metasedimentary rocks overlain by lower-grade Triassic metasedimentary and metavolcanic rocks and intruded by Jurassic calc-alkaline plutons. The Paleozoic rocks correlate well in age and lithology with rocks of the Sicker and Buttle Lake Groups of the Wrangellia terrane on Vancouver Island and differ from rocks of the Skolai Group that constitute basement to type-Wrangellia in the Wrangell Mountains. The Jurassic intrusive rocks are correlative with plutons that intrude the Wrangellia terrane on Vancouver Island but are lacking in the Wrangell Mountains. The rocks accreted beneath the arc complex are referred to as the Baranof Accretionary Complex in this report and are correlated with the Chugach Accretionary Complex of southern and southeastern Alaska and with the Pacific Rim Complex on Vancouver Island. Stratigraphic correlations between upper- and lower-plate rocks on Baranof Island and western Chichagof Island with rocks on Haida Gwaii and Vancouver Island, in addition to correlative ages of intrusive rocks and restorations of the Fairweather-Queen Charlotte, Chatham Strait, and Peril Strait Faults that define the Baranof-Chichagof block, suggest Baranof Island was near Vancouver Island at the time of initiation of arc magmatism in the Early Jurassic. Early Eocene plutons that intruded the accretionary complex outboard of the arc on Baranof Island are attributed to anatectic melting of trench sediments resulting from subduction of a spreading center. Oligocene intrusive rocks on Baranof Island correlate in age and composition with intrusive rocks in the Kano Plutonic Suite on Haida Gwaii, and similar magmatic sources are inferred.

Unroofing history of Late Paleozoic magmatic arcs within the ``Turan Plate'' (Tuarkyr, Turkmenistan)

NASA Astrophysics Data System (ADS)

Garzanti, E.; Gaetani, M.

2002-07-01

Stratigraphic, sedimentologic and petrographic data collected on the Kizilkaya sedimentary succession (Western Turkmenistan) demonstrate that the "Turan Plate" consists in fact of an amalgamation of Late Paleozoic to Triassic continental microblocks separated by ocean sutures. In the Kizilkaya area, an ophiolitic sequence including pyroxenite, gabbro, pillow basalt and chert, interpreted as the oceanic crust of a back-arc or intra-arc basin, is tectonically juxtaposed against volcaniclastic redbeds documenting penecontemporaneous felsic arc magmatism (Amanbulak Group). A collisional event took place around ?mid-Carboniferous times, when oceanic rocks underwent greenschist-facies metamorphism and a thick volcaniclastic wedge, with pyroclastic rocks interbedded in the lower part, accumulated (Kizilkaya Formation). The climax of orogenic activity is testified by arid fanglomerates shed from the rapid unroofing of a continental arc sequence, including Middle-Upper Devonian back-reef carbonates and cherts, and the underlying metamorphic and granitoid basement rocks (Yashmu Formation). After a short period of relative quiescence, renewed tectonic activity is indicated by a conglomeratic sequence documenting erosion of a sedimentary and metasedimentary succession including chert, sandstone, slate and a few carbonates. A final stage of rhyolitic magmatism took place during rapid unroofing of granitoid basement rocks (Kizildag Formation). Such a complex sequence of events recorded by the Kizilkaya episutural basin succession documents the stepwise assemblage of magmatic arcs and continental fragments to form the Turan microblock collage during the Late Paleozoic. Evolution of detrital modes is compatible with that predicted for juvenile to accreted and unroofed crustal blocks. The deposition of braidplain lithic arkoses in earliest Triassic time indicates that strong subsidence continued after the end of the volcanic activity, possibly in retroarc foreland basin settings. The occurrence of transgressive coquinas yielding endemic ammonoids ( Dorikranites) characteristic of the whole Caspian area suggests proximity to the southern margin of the newly formed Eurasian continent in the late Early Triassic. The Late Triassic Eo-Cimmerian Orogeny caused only mild tilting and rejuvenation of the underlying succession in the study area. Only at this time were the Turan blocks, a series of Indonesian-type terranes comprised between the Mashad Paleo-Tethys Suture in the south and the Mangyshlak belt in the north, finally incorporated into the Eurasian landmass.

Onshore/ Offshore Geologic Assessment for Carbon Storage in the Southeastern United States

NASA Astrophysics Data System (ADS)

Knapp, C. C.; Knapp, J. H.; Brantley, D.; Lakshmi, V.; Almutairi, K.; Almayahi, D.; Akintunde, O. M.; Ollmann, J.

2017-12-01

Eighty percent of the world's energy relies on fossil fuels and under increasingly stricter national and international regulations on greenhouse gas emissions storage of CO2 in geologic repositories seems to be not only a feasible, but also and vital solution for near/ mid-term reduction of carbon emissions. We have evaluated the feasibility of CO2 storage in saline formations of the Eastern North American Margin (ENAM) including (1) the Jurassic/Triassic (J/TR) sandstones of the buried South Georgia Rift (SGR) basin, and (2) the Mesozoic and Cenozoic geologic formations along the Mid- and South Atlantic seaboard. These analyses have included integration of subsurface geophysical data (2- and 3-D seismic surveys) with core samples, well logs as well as uses of geological databases and geospatial analysis leading to CO2 injection simulation models. ENAM is a complex and regionally extensive mature Mesozoic passive margin rift system encompassing: (1) a large volume and regional extent of related magmatism known as the Central Atlantic Magmatic Province (CAMP), (2) a complete stratigraphic column that records the post-rift evolution in several basins, (3) preserved lithospheric-scale pre-rift structures including Paleozoic sutures, and (4) a wide range of geological, geochemical, and geophysical studies both onshore and offshore. While the target reservoirs onshore show heterogeneity and a highly complex geologic evolution they also show promising conditions for significant safe CO2 storage away from the underground acquifers. Our offshore study (the Southeast Offshore Storage Resource Assessment - SOSRA) is focused on the outer continental shelf from North Carolina to the southern tip of Florida. Three old exploration wells are available to provide additional constraints on the seismic reflection profiles. Two of these wells (TRANSCO 1005-1 and COST GE-1) penetrate the pre-rift Paleozoic sedimentary formations while the EXXON 564-1 well penetrates the post-rift unconformity into the Mesozoic rocks. Preliminary results from the southeast Georgia Embayment suggest that Mesozoic strata can be good reservoirs for CO2 storage while Paleozoic and Cenozoic strata can be good lower and, respectively, upper seals.

Freshwater oligochaeta in mining subsidence ponds in the Upper Silesia region of southern Poland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krodkiewska, M.

I surveyed the benthic oligochaetes in three coal mining subsidence ponds in a heavily industrialized region of Upper Silesia, southern Poland. The fauna present differed in many respects from that living in natural and unpolluted water bodies. Nineteen species (11 Naididae and eight Tubificidae) were found. The two most consistently abundant species in all three ponds were Limnodrilus hoffimeisteri and Tubifex tubifex, both of which are ubiquitous and common in Poland. Polamothrix bavaricus, which is considered a rare species in Poland, was found consistently in the ponds.

Mineral resources of the southern half of Zone III Santander, Norte de Santander and Boyaca, Colombia

USGS Publications Warehouse

Ward, Dwight Edward; Goldsmith, Richard; Cruz, Bruna B.; Restrepo, Jaime; Hernan, A.

1970-01-01

The areas covered by this report lies in the eastern Cordillera of the Colombian Andes in the region around Bucaramanga. This part of the eastern Cordillera consists of a structurally complex core of metamorphic and igneous rocks of Precambrian to Mesozoic age, flanked to east and west by faulted and folded sedimentary strata of late Paleozoic to Tertiary age. Infaulted blocks of sedimentary rocks are locally present in the massif. Unconsolidated deposits of Quaternary age, primarily terraced alluvium, are 10cally extensive in valleys on the flanks of the range. The crystalline central core of the range is called the Santander massif. In it are located the principal sold deposits and scattered deposits of copper, lead, zinc, and fluorite. The sedimentary rocks flanking the massif contain significant deposits of phosphate rock and gypsum, as well as other nonmetallic industrial minerals such as limestone, barite, glass sand, and coal. A belt of lead-zinc prospects in carbonate and sandstone beds of Cretaceous age on the east side of the range warrants further investigation. Gold and silver are the only important metallic minerals that have been produced in the Santander massif. Mining dates back to colonial and possibly to pre-colonial times and continues on a small scale at present. The California and Vetas district was the main area of investigation of metallic minerals during the present project. Results of geochemical sampling of stream sediments and assays of vein material indicate that the main potential of the area is in gold with lesser potentials in copper, lead, zinc, and silver. Mineralization of the district is probably younger than Early Cretaceous. Although no copper minerals have been mined elsewhere in the massif, small amounts of copper minerals in various rocks in scattered areas is revealed by green and blue stains of copper carbonates and sulfates. Deposits of greatest areal extent are in arkosic conglomeratic beds of the Giron Formation. These are being explored and sampled at the present time (1969). A little lead has been mined and smelted in the past but operations were on a very small scale and of short duration. Small amounts of lead, zinc, and copper minerals accompany dolomite replacement of Cretaceous limestone in a few scattered places, and several promising prospects are being investigated by means of trenches and drilling. One magnetite and several hematite prospects were examined but none offers any potential for economic development. Thick beds of gypsum in Lower Cretaceous limestone on Mesa de Los Santos, south of Bucaramanga are being quarried from outcrops for use in cement manufacture. The deposit was discovered shortly before the present project began, and although its extent beneath overlying strata is not yet determined by drilling, it appears to be in a small evaporite basin of about three kilometers in radius. Reserves of gypsum are large, but future development will have to be by underground mining. Outcrops of Cretaceous limestone of high purity are widespread and are more than adequate to meet all demands, which at present are for cement and calcined lime, road construction material, and to a small extent for agricultural lime and polished decorative stone. Upper Paleozoic limestone of the Diamante Formation crops out in a few places; it has been used near Bucaramanga for cement manufacture. Marble is present in several localities of the Santander massif in Lower Paleozoic and Devonian rocks. Impurities, fractures, and solution cavities render most of it unsuitable for decorative purposes, but selected parts are used in floor tile and terrazo. Recrystallized limestone of the Diamante Formation in the same area, usually referred to as marble, is of uniform high purity throughout a thick and uninterrupted section, and offers a good source of limestone raw material. A little is now used for agricultural lime. The potential of this resource has not been fully evalua

The problem with coal-waste dumps inventory in Upper Silesian Coal Basin

NASA Astrophysics Data System (ADS)

Abramowicz, Anna; Chybiorz, Ryszard

2017-04-01

Coal-waste dumps are the side effect of coal mining, which has lasted in Poland for 250 years. They have negative influence on the landscape and the environment, and pollute soil, vegetation and groundwater. Their number, size and shape is changing over time, as new wastes have been produced and deposited changing their shape and enlarging their size. Moreover deposited wastes, especially overburned, are exploited for example road construction, also causing the shape and size change up to disappearing. Many databases and inventory systems were created in order to control these hazards, but some disadvantages prevent reliable statistics. Three representative databases were analyzed according to their structure and type of waste dumps description, classification and visualization. The main problem is correct classification of dumps in terms of their name and type. An additional difficulty is the accurate quantitative description (area and capacity). A complex database was created as a result of comparison, verification of the information contained in existing databases and its supplementation based on separate documentation. A variability analysis of coal-waste dumps over time is also included. The project has been financed from the funds of the Leading National Research Centre (KNOW) received by the Centre for Polar Studies for the period 2014-2018.

Assessment of Paleozoic shale gas resources in the Sichuan Basin of China, 2015

USGS Publications Warehouse

Potter, Christopher J.; Schenk, Christopher J.; Charpentier, Ronald R.; Gaswirth, Stephanie B.; Klett, Timothy R.; Leathers, Heidi M.; Brownfield, Michael E.; Mercier, Tracey J.; Tennyson, Marilyn E.; Pitman, Janet K.

2015-10-14

Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 23.9 trillion cubic feet of technically recoverable shale gas resources in Paleozoic formations in the Sichuan Basin of China.

Methodology of Estimation of Methane Emissions from Coal Mines in Poland

NASA Astrophysics Data System (ADS)

Patyńska, Renata

2014-03-01

Based on a literature review concerning methane emissions in Poland, it was stated in 2009 that the National Greenhouse Inventory 2007 [13] was published. It was prepared firstly to meet Poland's obligations resulting from point 3.1 Decision no. 280/2004/WE of the European Parliament and of the Council of 11 February 2004, concerning a mechanism for monitoring community greenhouse gas emissions and for implementing the Kyoto Protocol and secondly, for the United Nations Framework Convention on Climate Change (UNFCCC) and Kyoto Protocol. The National Greenhouse Inventory states that there are no detailed data concerning methane emissions in collieries in the Polish mining industry. That is why the methane emission in the methane coal mines of Górnośląskie Zagłębie Węglowe - GZW (Upper Silesian Coal Basin - USCB) in Poland was meticulously studied and evaluated. The applied methodology for estimating methane emission from the GZW coal mining system was used for the four basic sources of its emission. Methane emission during the mining and post-mining process. Such an approach resulted from the IPCC guidelines of 2006 [10]. Updating the proposed methods (IPCC2006) of estimating the methane emissions of hard coal mines (active and abandoned ones) in Poland, assumes that the methane emission factor (EF) is calculated based on methane coal mine output and actual values of absolute methane content. The result of verifying the method of estimating methane emission during the mining process for Polish coal mines is the equation of methane emission factor EF.

Interrelating the breakage and composition of mined and drill core coal

NASA Astrophysics Data System (ADS)

Wilson, Terril Edward

Particle size distribution of coal is important if the coal is to be beneficiated, or if a coal sales contract includes particle size specifications. An exploration bore core sample of coal ought to be reduced from its original cylindrical form to a particle size distribution and particle composition that reflects, insofar as possible, a process stream of raw coal it represents. Often, coal cores are reduced with a laboratory crushing machine, the product of which does not match the raw coal size distribution. This study proceeds from work in coal bore core reduction by Australian investigators. In this study, as differentiated from the Australian work, drop-shatter impact breakage followed by dry batch tumbling in steel cylinder rotated about its transverse axis are employed to characterize the core material in terms of first-order and zeroth-order breakage rate constants, which are indices of the propensity of the coal to degrade during excavation and handling. Initial drop-shatter and dry tumbling calibrations were done with synthetic cores composed of controlled low-strength concrete incorporating fly ash (as a partial substitute for Portland cement) in order to reduce material variables and conserve difficult-to-obtain coal cores. Cores of three different coalbeds--Illinois No. 6, Upper Freeport, and Pocahontas No. 5 were subjected to drop-shatter and dry batch tumbling tests to determine breakage response. First-order breakage, characterized by a first-order breakage index for each coal, occurred in the drop-shatter tests. First- and zeroth-order breakage occurred in dry batch tumbling; disappearance of coarse particles and creation of fine particles occurred in a systematic way that could be represented mathematically. Certain of the coal cores available for testing were dry and friable. Comparison of coal preparation plant feed with a crushed bore core and a bore core prepared by drop-shatter and tumbling (all from the same Illinois No.6 coal mining property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core. An attempt to determine breakage parameters (to allow use of selection and breakage functions and population balance models in the description of bore core size reduction) was initiated. Rank determination of the three coal types was done, indicating that higher rank associates with higher breakage propensity. The two step procedure of drop-shatter and dry batch tumbling simulates the first-order (volume breakage) and zeroth-order (abrasion of particle surfaces) that occur in excavation and handling operations, and is appropriate for drill core reduction prior to laboratory analysis.

Fuel Flexibility in Gasification

DOE Office of Scientific and Technical Information (OSTI.GOV)

McLendon, T. Robert; Pineault, Richard L.; Richardson, Steven W.

2001-11-06

In order to increase efficiencies of carbonizers, operation at high pressures is needed. In addition, waste biomass fuels of opportunity can be used to offset fossil fuel use. The National Energy Technology Laboratory (NETL) Fluidized Bed Gasifier/Combustor (FBG/C) was used to gasify coal and mixtures of coal and biomass (sawdust) at 425 psig. The purpose of the testing program was to generate steady state operating data for modeling efforts of carbonizers. A test program was completed with a matrix of parameters varied one at a time in order to avoid second order interactions. Variables were: coal feed rate, pressure, andmore » varying mixtures of sawdust and coal types. Coal types were Montana Rosebud subbituminous and Pittsburgh No. 8 bituminous. The sawdust was sanding waste from a furniture manufacturer in upstate New York. Coal was sieved from -14 to +60 mesh and sawdust was sieved to -14 mesh. The FBG/C operates at a nominal 425 psig, but pressures can be lowered. For the tests reported it was operated as a jetting, fluidized bed, ash-agglomerating gasifier. Preheated air and steam are injected into the center of the bottom along with the solid feed that is conveyed with cool air. Fairly stable reactor internal flow patterns develop and temperatures stabilize (with some fluctuations) when steady state is reached. At nominal conditions the solids residence time in the reactor is on the order of 1.5 to 2 hours, so changes in feed types can require on the order of hours to equilibrate. Changes in operating conditions (e.g. feed rate) usually require much less time. The operating periods of interest for these tests were only the steady state periods, so transient conditions were not monitored as closely. The test matrix first established a base case of operations to which single parameter changes in conditions could be compared. The base case used Montana Rosebud at a coal feed rate of 70 lbm/hr at 425 psig. The coal sawdust mixtures are reported as percent by weight coal to percent by weight sawdust. The mixtures of interest were: 65/35 subbituminous, 75/25 subbituminous, 85/15 subbituminous, and 75/25 bituminous. Steady state was achieved quickly when going from one subbituminous mixture to another, but longer when going from subbituminous to bituminous coal. The most apparent observation when comparing the base case to subbituminous coal/sawdust mixtures is that operating conditions are nearly the same. Product gas does not change much in composition and temperatures remain nearly the same. Comparisons of identical weight ratios of sawdust and subbituminous and bituminous mixtures show considerable changes in operating conditions and gas composition. The highly caking bituminous coal used in this test swelled up and became about half as dense as the comparable subbituminous coal char. Some adjustments were required in accommodating changes in solids removal during the test. Nearly all the solids in the bituminous coal sawdust were conveyed into the upper freeboard section and removed at the mid-level of the reactor. This is in marked contrast to the ash-agglomerating condition where most solids are removed at the very bottom of the gasifier. Temperatures in the bottom of the reactor during the bituminous test were very high and difficult to control. The most significant discovery of the tests was that the addition of sawdust allowed gasification of a coal type that had previously resulted in nearly instant clinkering of the gasifier. Several previous attempts at using Pittsburgh No. 8 were done only at the end of the tests when shutdown was imminent anyway. It is speculated that the fine wood dust somehow coats the pyrolyzed sticky bituminous coal particles and prevents them from agglomerating quickly. As the bituminous coal char particles swell, they are carried to the cooler upper regions of the reactor where they re-solidify. Other interesting phenomena were revealed regarding the transport (rheological) properties of the coal sawdust mixtures. The coal sawdust mixtures segregate quickly when transported. This is visibly apparent. To prevent bridges and ratholes from developing in the lowest coal feed hopper, it is normally fluidized. When feeding the coal sawdust mixtures the fluidizing gas was turned off to prevent segregation. The feed system worked as well with no fluidizing gas when using the mixtures as it did with fluidizing gas and only coal. In addition, it was inadvertently discovered that greatly increased pressure above the feeder resulted in greatly increased flow with the mixtures. Increased pressure above the feeder with coal only results in quickly plugging the feed system. Also, it was learned that addition of sawdust reduces the system loss during conveying compared to coal only. This is in spite of overall smaller particle sizes with the coal sawdust mixtures.« less

Geochemistry and chronology of the early Paleozoic diorites and granites in the Huangtupo volcanogenic massive sulfide (VMS) deposit, Eastern Tianshan, NW China: Implications for petrogenesis and geodynamic setting

NASA Astrophysics Data System (ADS)

Zheng, Jiahao; Chai, Fengmei; Feng, Wanyi; Yang, Fuquan; Shen, Ping

2018-03-01

The Eastern Tianshan orogen contains many late Paleozoic porphyry Cu and magmatic Cu-Ni deposits. Recent studies demonstrate that several early Paleozoic volcanogenic massive sulfide (VMS) Cu-polymetallic and porphyry Cu deposits were discovered in the northern part of Eastern Tianshan. This study presents zircon U-Pb, whole-rock geochemical, and Sr-Nd isotopic data for granites and diorites from the Huangtupo VMS Cu-Zn deposit, northern part of the Eastern Tianshan. Our results can provide constraints on the genesis of intermediate and felsic intrusions as well as early Paleozoic geodynamic setting of the northern part of Eastern Tianshan. LA-ICP-MS zircon U-Pb analyses suggest that the granites and diorites were formed at 435 ± 2 Ma and 440 ± 2 Ma, respectively. Geochemical characteristics suggest that the Huangtupo granites and diorites are metaluminous rocks, exhibiting typical subduction-related features such as enrichment in LILE and LREE and depletion in HFSE. The diorites have moderate Mg#, positive εNd(t) values (+6.4 to +7.3), and young Nd model ages, indicative of a depleted mantle origin. The granites exhibit mineral assemblages and geochemical characteristics of I-type granites, and they have positive εNd(t) values (+6.7 to +10.2) and young Nd model ages, suggesting a juvenile crust origin. The early Paleozoic VMS Cu-polymetallic and porphyry Cu deposits in the northern part of Eastern Tianshan were genetically related. The formation of the early Paleozoic magmatic rocks as well as VMS and porphyry Cu deposits in the northern part of Eastern Tianshan was due to a southward subduction of the Junggar oceanic plate.

Early Paleozoic subduction initiation volcanism of the Iwatsubodani Formation, Hida Gaien belt, Southwest Japan

NASA Astrophysics Data System (ADS)

Tsukada, Kazuhiro; Yamamoto, Koshi; Gantumur, Onon; Nuramkhaan, Manchuk

2017-06-01

In placing Japanese tectonics in an Asian context, variation in the Paleozoic geological environment is a significant issue. This paper investigates the geochemistry of the lower Paleozoic basalt formation (Iwatsubodani Formation) in the Hida Gaien belt, Japan, to consider its tectonic setting. This formation includes the following two types of rock in ascending order: basalt A with sub-ophitic texture and basalt B with porphyritic texture. Basalt A has a high and uniform FeO*/MgO ratio, moderate TiO2, high V, and low Ti/V. The HFSE and REE are nearly the same as those in MORB, and all the data points to basalt A being the "MORB-like fore-arc tholeiitic basalt (FAB)" reported, for example, from the Izu-Bonin-Mariana arc. By contrast, basalt B has a low FeO*/MgO ratio, low TiO2, and low V and Ti/V. It has an LREE-enriched trend and a distinct negative Nb anomaly in the MORB-normalized multi-element pattern and a moderately high LREE/HREE. All these factors suggest that basalt B is calc-alkaline basalt. It is known that FAB is erupted at the earliest stage of arc formation—namely, subduction initiation—and that boninitic/tholeiitic/calc-alkaline volcanism follows at the supra-subduction zone (SSZ). Thus, the occurrence of basalts A (FAB) and B (calc-alkaline rock) is strong evidence of early Paleozoic arc-formation initiation at an SSZ. Evidence for an early Paleozoic SSZ arc is also recognized from the Oeyama, Hayachine-Miyamori, and Sergeevka ophiolites. Hence, both these ophiolites and the Iwatsubodani Formation probably coexisted in a primitive SSZ system in the early Paleozoic.

Analytical modeling of mercury injection in high-rank coalbed methane reservoirs based on pores and microfractures: a case study of the upper carboniferous Taiyuan Formation in the Heshun block of the Qinshui Basin, central China

NASA Astrophysics Data System (ADS)

Gu, Yang; Ding, Wenlong; Yin, Shuai; Wang, Ruyue; Mei, Yonggui; Liu, Jianjun

2017-03-01

The coalbed gas reservoirs in the Qinshui Basin in central China are highly heterogeneous; thus, the reservoir characteristics are difficult to assess. Research on the pore structure of a reservoir can provide a basis for understanding the occurrence and seepage mechanisms of coal reservoirs, rock physics modeling and the formulation of rational development plans. Therefore, the pore structure characteristics of the coalbed gas reservoirs in the high rank bituminous coal in the No. 15 coal seam of the Carboniferous Taiyuan Group in the Heshun coalbed methane (CBM) blocks in the northeastern Qinshui Basin were analyzed based on pressure mercury and scanning electron microscopy data. The results showed that the effective porosity system of the coal reservoir was mainly composed of pores and microfractures and that the pore throat configuration of the coal reservoir was composed of pores and microthroats. A model was developed based on the porosity and microfractures of the high rank coal rock and the mercury injection and drainage curves. The mercury injection curve model and the coal permeability are well correlated and were more reliable for the analysis of coal and rock pore system connectivity than the mercury drainage curve model. Coal rocks with developed microfractures are highly permeable; the production levels are often high during the initial drainage stages, but they decrease rapidly. A significant portion of the natural gas remains in the strata and cannot be exploited; therefore, the ultimate recovery is rather low. Coal samples with underdeveloped microfractures have lower permeabilities. While the initial production levels are lower, the production cycle is longer, and the ultimate recovery is higher. Therefore, the initial production levels of coal reservoirs with poorly developed microfractures in some regions of China may be low. However, over the long term, due to their higher ultimate recoveries and longer production cycles, the total gas production levels will increase. This understanding can provide an important reference for developing appropriate CBM development plans.

Coal test drilling for the DE-NA-Zin Bisti Area, San Juan County, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, R.W.; Jentgen, R.W.

1980-01-01

From October 1978 to June 1979, the US Geological Survey (USGS) drilled 51 test holes, and cored 9 holes, in the vicinity of the Bisti Trading Post in the southwestern part of the San Juan Basin, San Juan County, New Mexico. The drilling was done in response to expressions of interest received by the Bureau of Land Management concerning coal leasing and, in some places, badlands preservation. The object of the drilling was to determine the depth, thickness, extent, and quality of the coal in the Upper Cretaceous Fruitland Formation in northwest New Mexico. The holes were geophysically logged immediatelymore » after drilling. Resistivity spontaneous-potential, and natural gamma logs were run in all of the holes. A high-resolution density log was also run in all holes drilled before January 13, when a logging unit from the USGS in Albuquerque was available. After January 13, the holes were logged by a USGS unit from Casper, Wyoming that lacked density logging capabilities. At nine locations a second hole was drilled, about 20 ft from the first hole, down to selected coal-bearing intervals and the coal beds were cored. A detailed description of each of the cores is given on the page(s) following the logs for each hole. From these coal cores, 32 intervals were selected and submitted to the Department of Energy in Pittsburgh, Pennsylvania, for analysis.« less

The main features of the Uralian Paleozoic magmatism and the epioceanic nature of the orogen

NASA Astrophysics Data System (ADS)

Fershtater, G. B.

2013-02-01

The 2000 km Uralian Paleozoic orogen is situated on the western flank of the Uralo-Mongolian folded belt. It is characterized by an abundant variety of magmatic rocks and related ore deposits. Uralian Paleozoic magmatism is entirely subduction-related. It is proposed that the Uralian orogen represents a cold mobile belt in which the mantle temperature was 200 to 500 °C cooler than in the adjacent areas; a situation which is similar to the modern West Pacific Triangle Zone including Indonesia, the Philippine Islands, and southern Asia. During the course of the geological evolution of the Uralian orogen, the nature of the magmatism has changed from basic rocks of indisputable mantle origin (460-390 Ma) to mantle-crust gabbro-granitic complexes (370-315 Ma) followed by pure crustal granite magmatism (290-250 Ma). This order in rock type and age reflects the evolution of Paleozoic magmatic complexes from the beginning of subduction to the final stages of the orogen development.

Performance of double-layer biofilter packed with coal fly ash ceramic granules in treating highly polluted river water.

PubMed

Jing, Zhaoqian; Li, Yu-You; Cao, Shiwei; Liu, Yuyu

2012-09-01

To improve trickling filters' denitrification efficiency, a biofilter with a trickling upper layer and a submerged lower layer was developed and applied in treating highly polluted river water. It was packed with porous coal fly ash ceramic granules. Its start-up characteristics, influence of hydraulic loading rates (HLR), carbon/nitrogen (C/N) ratio and filter depth on pollutants removal were investigated. The results indicated this biofilter was started quickly in 16 days with river sediment as inoculum. Alternating nitrification and denitrification were achieved when water flowed downwards. COD and nitrogen were mainly removed in the upper layer and the lower layer, respectively. With HLR of 4.0-5.0m(3)/(m(2)d), chemical oxygen demand (COD), ammonium (NH(4)(+)-N) and total nitrogen (TN) in the effluent were below 50, 5 and 15 mg/L, respectively. This biofilter removed more than 80% of COD, 85% of NH(4)(+)-N and 60% of TN with C/N ratios ranging from 6 to 10. Copyright © 2012 Elsevier Ltd. All rights reserved.

Detection of induced seismicity effects on ground surface using data from Sentinel 1A/1B satellites

NASA Astrophysics Data System (ADS)

Milczarek, W.

2017-12-01

Induced seismicity is the result of human activity and manifests itself in the form of shock and vibration of the ground surface. One of the most common factors causing the occurrence of induced shocks is underground mining activity. Sufficiently strong high-energy shocks may cause displacements of the ground surface. This type of shocks can have a significant impact on buildings and infrastructure. Assessment of the size and influence of induced seismicity on the ground surface is one of the major problems associated with mining activity. In Poland (Central Eastern Europe) induced seismicity occurs in the area of hard coal mining in the Upper Silesian Coal Basin and in the area of the Legnica - Głogów Copper Basin.The study presents an assessment of the use of satellite radar data (SAR) for the detection influence of induced seismicity in mining regions. Selected induced shocks from the period 2015- 2017 which occurred in the Upper Silesian Coal Basin and the Legnica - Głogów Copper Basin areas have been analyzed. In the calculations SAR data from the Sentinel 1A and Sentinel 1B satellites have been used. The results indicate the possibility of quickly and accurate detection of ground surface displacements after an induced shock. The results of SAR data processing were compared with the results from geodetic measurements. It has been shown that SAR data can be used to detect ground surface displacements on the relative small regions.

Calibration parameters used to simulate streamflow from application of the Hydrologic Simulation Program-FORTRAN Model (HSPF) to mountainous basins containing coal mines in West Virginia

USGS Publications Warehouse

Atkins, John T.; Wiley, Jeffrey B.; Paybins, Katherine S.

2005-01-01

This report presents the Hydrologic Simulation Program-FORTRAN Model (HSPF) parameters for eight basins in the coal-mining region of West Virginia. The magnitude and characteristics of model parameters from this study will assist users of HSPF in simulating streamflow at other basins in the coal-mining region of West Virginia. The parameter for nominal capacity of the upper-zone storage, UZSN, increased from south to north. The increase in UZSN with the increase in basin latitude could be due to decreasing slopes, decreasing rockiness of the soils, and increasing soil depths from south to north. A special action was given to the parameter for fraction of ground-water inflow that flows to inactive ground water, DEEPFR. The basis for this special action was related to the seasonal movement of the water table and transpiration from trees. The models were most sensitive to DEEPFR and the parameter for interception storage capacity, CEPSC. The models were also fairly sensitive to the parameter for an index representing the infiltration capacity of the soil, INFILT; the parameter for indicating the behavior of the ground-water recession flow, KVARY; the parameter for the basic ground-water recession rate, AGWRC; the parameter for nominal capacity of the upper zone storage, UZSN; the parameter for the interflow inflow, INTFW; the parameter for the interflow recession constant, IRC; and the parameter for lower zone evapotranspiration, LZETP.

Lithospheric mantle structure beneath Northern Scotland: Pre-plume remnant or syn-plume signature?

NASA Astrophysics Data System (ADS)

Knapp, J.

2003-04-01

Upper mantle reflectors (Flannan and W) beneath the northwestern British Isles are some of the best-known and most-studied examples of preserved structure within the continental mantle lithosphere, and are spatially coincident with the surface location of early Iceland plume volcanism in the British Tertiary Province. First observed on BIRPS (British Institutions Reflection Profiling Syndicate) marine deep seismic reflection profiles in the early 1980's, these reflectors have subsequently been imaged and correlated on additional reflection and refraction profiles in the offshore area of northern and western Scotland. The age and tectonic significance of these reflectors remains a subject of wide debate, due in part to the absence of robust characterization of the upper mantle velocity structure in this tectonically complex area. Interpretations advanced over the past two decades for the dipping Flannan reflector range from fossilized subduction complex to large-scale extensional shear zone, and span ages from Proterozoic to early Mesozoic. Crustal geology of the region records early Paleozoic continental collision and late Paleozoic to Mesozoic extension. Significant modification of the British lithosphere in early Tertiary time, including dramatic thinning and extensive basaltic intrusion associated with initiation and development of the Iceland plume, suggests either (1) an early Tertiary age for the Flannan reflector or (2) preservation of ancient features within the mantle lithosphere despite such pervasive modification. Exisitng constraints are consistent with a model for early Tertiary origin of the Flannan reflector as the downdip continuation of the Rockall Trough extensional system of latest Cretaceous to earliest Tertiary age during opening of the northern Atlantic Ocean and initiation of the Iceland plume. Lithopsheric thinning beneath present-day northern Scotland could have served to focus the early expression of plume volcanism (British Tertiary Province), despite the inferred distant locus of the initial plume head. Alternatively, preservation of large-scale pre-plume fabric in the Scottish mantle would imply long-lived tectonic heredity in the continental lithospheric mantle, and place important constraints on the plume-related effects (or lack thereof) in the mantle lithosphere.

An Upper Paleozoic bio-chronostratigraphic scheme for the western margin of Gondwana

NASA Astrophysics Data System (ADS)

Césari, Silvia N.; Limarino, Carlos O.; Gulbranson, Erik L.

2011-05-01

The Carboniferous and Permian fossiliferous sequences of the central-western Argentina contain abundant plant remains, palynomorphs and invertebrates. They include a continuous record of large distribution in the Paganzo, Rio Blanco, Calingasta-Uspallata and San Rafael Basins. The most recent biostratigraphic schemes recognize a floristic succession represented by the biozones: Archaeosigillaria-Frenguellia (AF Biozone), Frenguellia eximia-Nothorhacopteris kellaybelenensis-Cordaicarpus cesarii (FNC Biozone), Nothorhacopteris-Botrychiopsis- Ginkgophyllum (NBG Biozone), Interval Biozone and Gangamopteris Biozone. The associated palynological record is represented by the biozones: Reticulatisporites magnidictyus-Verrucosisporites quasigobbetti (MQ Biozone), Raistrickia densa-Convolutispora muriornata (DM Biozone), Pakhapites fusus-Vittatina subsaccata (FS Biozone), and Lueckisporites-Weylandites (LW Biozone). The precise age of the Upper Paleozoic western Gondwanan biozones has been under discussion and remains controversial to date in some regions. The main issue hampering an integrated comparison of the Gondwanan biozones was its imprecise chronostratigraphic framework. However, new studies in some Argentinian stratigraphic sections bearing floras and faunas have yielded several radiometric ages. From these 206Pb/ 238U zircon datings it is possible to determine the chronostratigraphic range of many fossiliferous assemblages in this sector of Gondwana. In this way, the AF and MQ Biozones are restricted to the Late Mississippian and they would be not younger than 335 Ma according to radiometric ages. 206Pb/ 238U ages suggest that the NBG, DMa and DMb Biozones characterize the Late Serpukhovian glacial deposits and persisted up to the Late Bashkirian. Beds containing the Interval and DMc Biozones have yielded 206Pb/ 238U ages of 312.82 ± 0.11 Ma and 310.71 ± 0.1 Ma which would indicate that both zones characterize the Moscovian. The remains of Gangamopteris Biozone found in the Paganzo Basin overlie basalt levels ranging between 308 ± 6 and 293 ± 6 Ma. Therefore, the incoming of the first glossopterids was closely associated to the Carboniferous-Permian boundary in this part of Gondwana. The data presented in this paper are used for establishing comparisons with other Gondwanan biozones, constrained by absolute ages.

A lone biodetrital mound in the Chesterian (Carboniferous) of Alabama?

USGS Publications Warehouse

Kopaska-Merkel, D. C.; Haywick, D.W.

2001-01-01

A carbonate mound in the Chesterian Bangor Limestone of Lawrence County, Alabama, consists chiefly of packstone and grainstone dominated by echinoderm ossicles and fragments of fenestrate bryozoans. In-situ colonies of the rugose coral Caninia flaccida comprise about 8% of the mound by volume. The exposed portion of the mound is approximately 25 m wide, 1.6 m thick at the thickest point and roughly circular in plan. The mound developed on top of a shallow ooid shoal that had been cemented and stabilised during an earlier episode of sub-aerial exposure. Subsequent flooding of the exposed shoal surface permitted establishment of the mound biota. Lateral and vertical facies relationships suggest that the mound possessed about 45 cm of synoptic relief when fully developed. Rugose corals, fenestrate and ramose bryozoans, stalked echinoderms, and sessile soft-bodied organisms encrusted by foraminifera colonised the shoal, forming a mound. Baffling resulted in deposition of mixed-fossil packstone containing locally derived debris and coated grains from the surrounding sea floor. Strong currents within the mound are indicated by preferred orientation of corals and by coarse, commonly cross-stratified grainstone in channels between neighboring coral colonies. Corals are most abundant on the windward side of the mound, where they account for about 13% of the mound compared to 6- 10% in the central part of the mound, and 2-4% on the leeward flank. Biodetrital mounds such as the one described here are uncommon in upper Paleozoic strata and previously unknown in the Bangor Limestone. Of 10 carbonate buildups we examined in the Bangor in Alabama and Tennessee, only one is a biodetrital mound. Two are rugose coral-microbial reefs, one is a coral biostrome, and six are dominated by microbialite. The Bangor shelf, previously interpreted as sedimentologically simple, appears to contain many small mounds of quite varied characteristics. Also, the discovery of a biodetrital mound in the Chesterian of Alabama suggests that there may be more kinds of upper Paleozoic mounds than commonly acknowledged. ?? 2001 Elsevier Science B.V. All rights reserved.

Silurian extension in the Upper Connecticut Valley, United States and the origin of middle Paleozoic basins in the Québec embayment

USGS Publications Warehouse

Rankin, D.W.; Coish, R.A.; Tucker, R.D.; Peng, Z.X.; Wilson, S.A.; Rouff, A.A.

2007-01-01

Pre-Silurian strata of the Bronson Hill arch (BHA) in the Upper Connecticut Valley, NH-VT are host to the latest Ludlow Comerford Intrusive Suite consisting, east to west, of a mafic dike swarm with sheeted dikes, and an intrusive complex. The rocks are mostly mafic but with compositions ranging from gabbro to leucocratic tonalite. The suite is truncated on the west by the Monroe fault, a late Acadian thrust that carries rocks of the BHA westward over Silurian-Devonian strata of the Connecticut Valley-Gaspe?? trough (CVGT). Dikes intrude folded strata with a pre-intrusion metamorphic fabric (Taconian?) but they experienced Acadian deformation. Twenty fractions of zircon and baddeleyite from three sample sites of gabbrodiorite spanning nearly 40 km yield a weighted 207Pb/206Pb age of 419 ?? 1 Ma. Greenschist-facies dikes, sampled over a strike distance of 35 km, were tholeiitic basalts formed by partial melting of asthenospheric mantle, with little or no influence from mantle or crustal lithosphere. The dike chemistry is similar to mid-ocean ridge, within-plate, and back-arc basin basalts. Parent magmas originated in the asthenosphere and were erupted through severely thinned lithosphere adjacent to the CVGT. Extensive middle Paleozoic basins in the internides of the Appalachian orogen are restricted to the Que??bec embayment of the Laurentian rifted margin, and include the CVGT and the Central Maine trough (CMT), separated from the BHA by a Silurian tectonic hinge. The NE-trending Comerford intrusions parallel the CVGT, CMT, and the tectonic hinge, and indicate NW-SE extension. During post-Taconian convergence, the irregular margins of composite Laurentia and Avalon permitted continued collision in Newfoundland (St. Lawrence promontory) and coeval extension in the Que??bec embayment. Extension may be related to hinge retreat of the northwest directed Brunswick subduction complex and rise of the asthenosphere following slab break-off. An alternative hypothesis is that the basins originated as pull-apart basins between northwest-trending, left-stepping, sinistral strike-slip faults along the southern flanks of the New York and St. Lawrence promontories.

A terrestrial fauna from the Scottish Lower Carboniferous

NASA Astrophysics Data System (ADS)

Wood, S. P.; Panchen, A. L.; Smithson, T. R.

1985-03-01

Despite several important discoveries, extending over more than 120 years, our knowledge of early land vertebrates is still sparse. The earliest tetrapod remains are known from the Upper Devonian of East Greenland1-3 and Australia4-6, but the tetrapod fossil record does not become plentiful until Coal Measure times, in the Upper Carboniferous, some 50 Myr later. Finds in the Lower Carboniferous are very few indeed. Apart from two localities in West Virginia, USA7,8, and one in Nova Scotia, Canada9, all other Lower Carboniferous tetrapod sites are from the Viséan of Fife and the Lothian Region, Scotland10,11. We report here the discovery of an assemblage of terrestrial animals from a new Lower Carboniferous locality in the Lothian Region. Specimens were collected from the East Kirkton Limestone in the Brigantian stage of the Scottish Viséan, and include the first articulated amphibian skeleton to be found in the Lower Carboniferous of Europe in the twentieth century. This find is the earliest well-preserved amphibian skeleton ever discovered. The associated fauna is remarkable for the presence of myriapods, scorpions, the earliest known harvest-man and several other types of amphibian. The presence of such forms, together with the striking absence of fishes, suggests that the amphibians form an integral part of a terrestrial fauna; terrestrial amphibians are otherwise unknown before the Upper Carboniferous Coal Measures.

The geology and petroleum potential of the North Afghan platform and adjacent areas (northern Afghanistan, with parts of southern Turkmenistan, Uzbekistan and Tajikistan)

NASA Astrophysics Data System (ADS)

Brookfield, Michael E.; Hashmat, Ajruddin

2001-10-01

The North Afghan platform has a pre-Jurassic basement unconformably overlain by a Jurassic to Paleogene oil- and gas-bearing sedimentary rock platform cover, unconformably overlain by Neogene syn- and post-orogenic continental clastics. The pre-Jurassic basement has four units: (1) An ?Ordovician to Lower Devonian passive margin succession developed on oceanic crust. (2) An Upper Devonian to Lower Carboniferous (Tournaisian) magmatic arc succession developed on the passive margin. (3) A Lower Carboniferous (?Visean) to Permian rift-passive margin succession. (4) A Triassic continental magmatic arc succession. The Mesozoic-Palaeogene cover has three units: (1) A ?Late Triassic to Middle Jurassic rift succession is dominated by variable continental clastics. Thick, coarse, lenticular coal-bearing clastics were deposited by braided and meandering streams in linear grabens, while bauxites formed on the adjacent horsts. (2) A Middle to Upper Jurassic transgressive-regressive succession consists of mixed continental and marine Bathonian to Lower Kimmeridgian clastics and carbonates overlain by regressive Upper Kimmeridgian-Tithonian evaporite-bearing clastics. (3) A Cretaceous succession consists of Lower Cretaceous red beds with evaporites, resting unconformably on Jurassic and older deposits, overlain (usually unconformably) by Cenomanian to Maastrichtian shallow marine limestones, which form a fairly uniform transgressive succession across most of Afghanistan. (4) A Palaeogene succession rests on the Upper Cretaceous limestones, with a minor break marked by bauxite in places. Thin Palaeocene to Upper Eocene limestones with gypsum are overlain by thin conglomerates, which pass up into shales with a restricted brackish-water ?Upper Oligocene-?Lower Miocene marine fauna. The Neogene succession consists of a variable thickness of coarse continental sediments derived from the rising Pamir mountains and adjacent ranges. Almost all the deformation of the North Afghan platform began in the Miocene. Oil and gas traps are mainly in Upper Jurassic carbonates and Lower Cretaceous sandstones across the entire North Afghan block. Upper Jurassic carbonate traps, sealed by evaporites, occur mainly north of the southern limit of the Upper Jurassic salt. Lower Cretaceous traps consist of fine-grained continental sandstones, sealed by Aptian-Albian shales and siltstones. Upper Cretaceous-Palaeocene carbonates, sealed by Palaeogene shales are the main traps along the northern edge of the platform and in the Tajik basin. Almost all the traps are broad anticlines related to Neogene wrench faulting, in this respect, like similar traps along the San Andreas fault. Hydrocarbon sources are in the Mesozoic section. The Lower-Middle Jurassic continental coal-bearing beds provide about 75% of the hydrocarbons; the Callovian-Oxfordian provides about 10%; the Neocomian a meagre 1%, and the Aptian-Albian about 14%. The coal-bearing source rocks decrease very markedly in thickness southwards cross the North Afghan platform. Much of the hydrocarbon generation probably occurred during the Late Cretaceous-Paleogene and migrated to structural traps during Neogene deformation. Since no regional structural dip aids southward hydrocarbon migration, and since the traps are all structural and somewhat small, then there is little chance of very large petroleum fields on the platform. Nevertheless, further studies of the North Afghan platform should be rewarding because: (a) the traps of strike-slip belts are difficult to find without detailed exploration; (b) the troubles of the last 20 years mean that almost no exploration has been done; and, (c) conditions may soon become more favorable. There should be ample potential for oil, and particularly gas, discoveries especially in the northern and western parts of the North Afghan platform.

Facies patterns and conodont biogeography in Arctic Alaska and the Canadian Arctic Islands: Evidence against juxtaposition of these areas during early Paleozoic time

USGS Publications Warehouse

Dumoulin, Julie A.; Harris, A.G.; Bradley, D.C.; De Freitas, T. A.

2000-01-01

Differences in lithofacies and biofacies suggest that lower Paleozoic rocks now exposed in Arctic Alaska and the Canadian Arctic Islands did not form as part of a single depositional system. Lithologic contrasts are noted in shallow- and deep-water strata and are especially marked in Ordovician and Silurian rocks. A widespread intraplatform basin of Early and Middle Ordovician age in northern Alaska has no counterpart in the Canadian Arctic, and the regional drowning and backstepping of the Silurian shelf margin in Canada has no known parallel in northern Alaska. Lower Paleozoic basinal facies in northern Alaska are chiefly siliciclastic, whereas resedimented carbonates are volumetrically important in Canada. Micro- and macrofossil assemblages from northern Alaska contain elements typical of both Siberian and Laurentian biotic provinces; coeval Canadian Arctic assemblages contain Laurentian forms but lack Siberian species. Siberian affinities in northern Alaskan biotas persist from at least Middle Cambrian through Mississippian time and appear to decrease in intensity from present-day west to east. Our lithologic and biogeographic data are most compatible with the hypothesis that northern Alaska-Chukotka formed a discrete tectonic block situated between Siberia and Laurentia in early Paleozoic time. If Arctic Alaska was juxtaposed with the Canadian Arctic prior to opening of the Canada basin, biotic constraints suggest that such juxtaposition took place no earlier than late Paleozoic time.

Petroleum geology and resources of the Dnieper-Donets Basin, Ukraine and Russia

USGS Publications Warehouse

Ulmishek, Gregory F.

2001-01-01

The Dnieper-Donets basin is almost entirely in Ukraine, and it is the principal producer of hydrocarbons in that country. A small southeastern part of the basin is in Russia. The basin is bounded by the Voronezh high of the Russian craton to the northeast and by the Ukrainian shield to the southwest. The basin is principally a Late Devonian rift that is overlain by a Carboniferous to Early Permian postrift sag. The Devonian rift structure extends northwestward into the Pripyat basin of Belarus; the two basins are separated by the Bragin-Loev uplift, which is a Devonian volcanic center. Southeastward, the Dnieper-Donets basin has a gradational boundary with the Donbas foldbelt, which is a structurally inverted and deformed part of the basin. The sedimentary succession of the basin consists of four tectono-stratigraphic sequences. The prerift platform sequence includes Middle Devonian to lower Frasnian, mainly clastic, rocks that were deposited in an extensive intracratonic basin. 1 The Upper Devonian synrift sequence probably is as thick as 4?5 kilometers. It is composed of marine carbonate, clastic, and volcanic rocks and two salt formations, of Frasnian and Famennian age, that are deformed into salt domes and plugs. The postrift sag sequence consists of Carboniferous and Lower Permian clastic marine and alluvial deltaic rocks that are as thick as 11 kilometers in the southeastern part of the basin. The Lower Permian interval includes a salt formation that is an important regional seal for oil and gas fields. The basin was affected by strong compression in Artinskian (Early Permian) time, when southeastern basin areas were uplifted and deeply eroded and the Donbas foldbelt was formed. The postrift platform sequence includes Triassic through Tertiary rocks that were deposited in a shallow platform depression that extended far beyond the Dnieper-Donets basin boundaries. A single total petroleum system encompassing the entire sedimentary succession is identified in the Dnieper-Donets basin. Discovered reserves of the system are 1.6 billion barrels of oil and 59 trillion cubic feet of gas. More than one-half of the reserves are in Lower Permian rocks below the salt seal. Most of remaining reserves are in upper Visean-Serpukhovian (Lower Carboniferous) strata. The majority of discovered fields are in salt-cored anticlines or in drapes over Devonian horst blocks; little exploration has been conducted for stratigraphic traps. Synrift Upper Devonian carbonate reservoirs are almost unexplored. Two identified source-rock intervals are the black anoxic shales and carbonates in the lower Visean and Devonian sections. However, additional source rocks possibly are present in the deep central area of the basin. The role of Carboniferous coals as a source rock for gas is uncertain; no coal-related gas has been identified by the limited geochemical studies. The source rocks are in the gas-generation window over most of the basin area; consequently gas dominates over oil in the reserves. Three assessment units were identified in the Dnieper-Donets Paleozoic total petroleum system. The assessment unit that contains all discovered reserves embraces postrift Carboniferous and younger rocks. This unit also contains the largest portion of undiscovered resources, especially gas. Stratigraphic and combination structural and stratigraphic traps probably will be the prime targets for future exploration. The second assessment unit includes poorly known synrift Devonian rocks. Carbonate reef reservoirs along the basin margins probably will contain most of the undiscovered resources. The third assessment unit is an unconventional, continuous, basin-centered gas accumulation in Carboniferous low-permeability clastic rocks. The entire extent of this accumulation is unknown, but it occupies much of the basin area. Resources of this assessment unit were not estimated quantitatively.

The Middle Jurassic microflora from El Maghara N° 4 borehole, Northern Sinai, Egypt

NASA Astrophysics Data System (ADS)

Mohsen, Sayed Abdel

The coal bearing formation in El Maghara area, northern Sinai, yielded abundant, diverse and generally well preserved spores, pollen and marine microflora. The palynological analysis of the fine clastic sediments in this formation yielded (71) species related to (44) genera. Three different palynological assemblage zones can be distinguished. The sediments which contain lower and the upper assemblage zones bearing the coal seems, were deposited in non-marine (swamp) environment. In the middle assemblage zone few marine microflora can be identified, indicating a coastal near shore marine environment. Compared with other palynologic data obtained from Egypt and other countries, the three described assemblage zones belong to Middle Jurassic (Bathonian) age.

Paleozoic-involving thrust array in the central Sierras Interiores (South Pyrenean Zone, Central Pyrenees): regional implications

NASA Astrophysics Data System (ADS)

Rodriguez, L.; Cuevas, J.; Tubía, J. M.

2012-04-01

This work deals with the structural evolution of the Sierras Interiores between the Tena and Aragon valleys. The Sierras Interiores is a WNW-trending mountain range that bounds the South Pyrenean Zone to the north and that is characterized by a thrust-fold system with a strong lithological control that places preferably decollements in Triassic evaporites. In the studied area of the Sierras Interiores Cenomanian limestones cover discordantly the Paleozoic rocks of the Axial Zone because there is a stratigraphic lacuna developed from Triassic to Late Cretaceous times. A simple lithostratigraphy of the study area is made up of Late Cenomanian to Early Campanian limestones with grey colour and massive aspect in landscape (170 m, Lower calcareous section), Campanian to Maastrichtian brown coloured sandstones (400-600 m, Marboré sandstones) and, finally, Paleocene light-coloured massive limestones (130-230 m), that often generate the higher topographic levels of the Sierras Interiores due to their greater resistance to erosion. Above the sedimentary sequence of the Sierras Interiores, the Jaca Basin flysch succession crops out discordantly. Based on a detailed mapping of the studied area of the Sierras Interiores, together with well and structural data of the Jaca Basin (Lanaja, 1987; Rodríguez and Cuevas, 2008) we have constructed a 12 km long NS cross section, approximately parallel to the movement direction deduced for this region (Rodríguez et al., 2011). The main structure is a thrust array made up of at least four Paleozoic-involving thrusts (the deeper thrust system) of similar thickness in a probably piggyback sequence, some of which are blind thrusts that generate fold-propagation-folds in upper levels. The higher thrust of the thrust array crops out duplicating the lower calcareous section all over the Sierras Interiores. The emplacement of the deeper thrust system generated the tightness of previous structures: south directed piggyback duplexes (the upper thrust system) affecting the Marboré sandstones and the Paleocene limestones, deformed by angular south-vergent folds and their related axial plane foliation. The transect explained above clearly summarizes the alpine evolution of northern part of the Sierras Interiores. Moreover, well data available indicate the presence of two thrust soled in the lower calcareous section covering Triassic evaporites at 5 km depth and 8 km to the south of the Sierras Interiores. Because the Triassic evaporites constitute a main decollement level in the South Pyrenean Zone, the deeper thrust system is associated to the emplacement of the Gavarnie nappe. Lanaja, J.M., 1987, Contribución de la exploración petrolífera al conocimiento de la Geología de España, IGME, Madrid, 465 p. Rodríguez, L., Cuevas, J., 2008. Geogaceta 44, 51-54. Rodríguez, L., Cuevas, J., Tubia, J.M., 2011. Geophysical Research Abstracts 13, 2273.

Studies on geological background and source of fluorine in drinking water in the North China Plate fluorosis areas

USGS Publications Warehouse

Luo, K.; Feng, F.; Li, H.; Chou, C.-L.; Feng, Z.; Yunshe, D.

2008-01-01

Endemic fluorosis in northern China is usually produced by high fluorine (F) content in drinking water. Thirty-one samples of drinking waters, mainly well waters and nearly 200 samples of rocks, loess, and coal were analyzed for F content using the combustion hydrolysis-fluoride-ion selective electrode (ISE) method. The geologic cross sections of two well-known fluorosis basins were studied. The solubility of F in different rock types collected from fluorosis areas was determined. Results showed that areas of endemic fluorosis in northern China are located in coal-bearing basins which are comprised of three stratagraphic portions. The lowest portion is Precambrian granitic rocks or Cambrian-Ordovician carbonates. The middle portion consists of Permo-Carboniferous or Jurassic coal-bearing sequences. The upper portion is 0-400 m Pleistocene loess. Flourine content in the Precambrian granite-gneiss contained (a) 1090-1460 ppm, in the Cambrian-Ordovician limestone and dolomite, (b) 52-133 ppm, in black shales and coal gob of Permo-Carboniferous coal-bearing strata, (c) 200-700 ppm, and (d) Pleistocene loess 454-542 ppm. The solubility of F in black shales of coal-bearing sequences was higher than in Precambrian granitic rocks, and both were more soluble than loess. F solubility from Precambrian granitic rocks was moderate, but Precambrian granitic rocks have high F content and thus contribute an appreciable amount of ion to the shallow groundwater (well water). Varying F content in shallow groundwater is controlled by geological conditions. The sources of F in the shallow groundwater from fluorosis areas in northern China are mainly derived from black shales of coal-bearing sequences and Precambrian granitic basement in the basins of northern China. ?? 2008 Taylor & Francis.

First early Mesozoic amber in the Western Hemisphere

USGS Publications Warehouse

Litwin, R.J.; Ash, S.R.

1991-01-01

Detrital amber pebbles and granules have been discovered in Upper Triassic strata on the Colorado Plateau. Although amber previously has been reported from Pennsylvanian, Jurassic, Cretaceous, and Tertiary strata, we know of no other reported Triassic occurrence in North America or the Western Hemisphere. The new discovered occurrences of amber are at two localities in the lower part of the Petrified Forest Member of the Upper Triassic Chinle Formation in Petrified Forest National Park, Arizona. The paper coals and carbonaceous paper shales containing the amber also contain fossil palynomorph assemblages that indicate a late Carnian age for these occurrences. -Authors

The pre-Mesozoic tectonic unit division of the Xing-Meng orogenic belt (XMOB)

NASA Astrophysics Data System (ADS)

Xu, Bei; Zhao, Pan

2014-05-01

According to the viewpoint that the paleo-Asian ocean closed by the end of early Paleozoic and extended during the late Paleozoic, a pre-Mesozoic tectonic unit division has been suggested. Five blocks and four sutures have been recognized in the pre-Devonia stage, the five blocks are called Erguna (EB), Xing'an (XB), Airgin Sum-Xilinhot (AXB), Songliao-Hunshandak (SHB) and Jiamusi (JB) blocks and four sutures, Xinlin-Xiguitu (XXS), Airgin Sum-Xilinhot-Heihe (AXHS), Ondor Sum-Jizhong-Yanji (OJYS) and Mudanjiang (MS) sutures. The EB contains the Precambrian base with the ages of 720-850Ma and ɛHf(T)=+2.5to +8.1. The XB is characterized by the Paleoproterozoic granitic gneiss with ɛHf(T)=-3.9 to -8.9. Several ages from 1150 to 1500 Ma bave been acquired in the AXB, proving presence of old block that links with Hutag Uul block in Mongolia to the west. The Paleoproterozoic (1.8-1.9Ga) and Neoproterozoic (750-850Ma) ages have been reported from southern and eastern parts of the SHB, respectively. As a small block in east margin of the XMOB, the JB outcrops magmatite and granitic gneiss bases with ages of 800-1000Ma. The XXS is marked by blueschists with zircon ages of 490-500Ma in Toudaoqiao village, ophiolites in Xiguitu County and granite with ages of about 500Ma along the northern segment of XXS. The AXHS is characterized by the early Paleozoic arc magmatic rocks with ages from 430Ma to 490Ma, mélange and the late Devonia molass basins, which indicates a northward subduction of the SHB beneath the AXB during the early-middle Paleozoic. The OJYS is composed of the early Paleozoic volcanic rocks, diorites and granites with ages of 425-475Ma, blueschists, ophiolitic mélange, the late Silurian flysch and Early-Middle Devonian molasses in western segment, granites (420-450Ma) in middle segment, and plagiogranites (443Ma) and the late Silurian molasses in eastern segment. This suture was caused by a southward subduction of the SHB beneath the North China block. The MS is between the SHB and JB, marked by the three phase granites of 485, 450 and 425Ma in the SHB. Tectonic units of the middle Devonian-Carboniferous tectonic stage include the middle-late Devonian continental basin, Carboniferious continental and epeiric sea basin, intrusive and irruptive igneous rock belt with ages from 300Ma to 330Ma containing granites, diorites, gabbros and biomodal volcanic rocks, and early Carboniferious ophiolites of 330-350Ma in Hegenshan and Erenhot. The Permian tectonic units can be divided into continental rift belt, ophiolite belt, alkaline rock belt and "red sea"-like ocean basin, which indicates an continuous extension environment during the Permian. The continental rift belt is composed of thick continental sedimentary rocks containing plant fossils, biomodal volcanic rocks (270-290Ma). The alkaline rocks can be divided into north and south belts by their distribution. The Solonker ophiolite is a thrust sheet that is inserted in a thrust stack containing the Upper Carboniferious epeiric sea clastic rocks and carbornates. The "red sea"-like ocean basin is characterized by basalt sequences with ages of 246-260Ma, which shows an affinity to E-MORB and a tendency towards OIB.

Isotopic composition of Pb in ore deposits of the Betic Cordillera, Spain; origin and relationship to other European deposits

USGS Publications Warehouse

Arribas , Antonio; Tosdal, Richard M.

1994-01-01

The Betic Cordillera in southern Spain is a complex Alpine fold belt that resulted from the Cretaceous through Cenozoic collision of Africa with Europe. The region is illustrative of one of the characteristics of the Alpine-Mediterranean orogen: the occurrence over a limited area of mineral deposits with a wide variety of host rocks, mineralization ages, and styles. The metamorphic basement in the Betic zone is characterized by a nappe structure of superimposed tectonostratigraphic units and consists of lower Paleozoic to Lower Triassic clastic metasedimentary rocks. This is overlain by Middle to Upper Triassic platform carbonate rocks with abundant strata-bound F-Pb-Zn-(Ba) deposits (e.g., Sierra de Gador, Sierra Alhamilla). Cretaceous to Paleogene subduction-related compression in southeastern Spain was followed by Miocene postcollisional extension and resulted in the formation of the Almeria-Cartagena volcanic belt and widespread hydrothermal activity and associated polymetallic mineralization. Typical Miocene hydrothermal deposits include volcanic-hosted Au (e.g., Rodalquilar) and Ag-rich base metal (e.g., Cabo de Gata, Mazarron) deposits as well as complex polymetallic veins, mantos, and irregular replacement bodies which are hosted by Paleozoic and Mesozoic metamorphic rocks and Neogene sedimentary and volcanic rocks (e.g., Cartagena, Sierra Almagrera, Sierra del Aguilon, Loma de Bas).Lead isotope compositions were measured on sulfide samples from nine ore districts and from representative fresh samples of volcanic and basement rock types of the region. The results have been used to evaluate ore-forming processes in southeastern Spain with emphasis on the sources of metals. During a Late Triassic mineralizing event, Pb was leached from Paleozoic clastic metasedimentary rocks and incorporated in galena in strata-bound F-Pb-Zn-(Ba) deposits ( 206 Pb/ 204 Pb = 18.332 + or - 12, 207Pb/ 204 Pb = 15.672 + or - 12, 208 Pb/ 204 Pb = 38.523 + or - 46). The second episode of mineralization was essentially contemporaneous (late Miocene) throughout the region and did not involve remobilization of less radiogenic Triassic ore Pb. Lead isotope data indicate a dominantly Paleozoic metasedimentary source for polymetallic vein- and manto-type deposits that formed by hydrothermal circulation through the Betic basement, driven by Miocene intrusions ( 206 Pb/ 204 Pb = 18.747 + or - 20, 207 Pb/ 204Pb = 15.685 + or - 9, 208 /Pb/ 204 Pb = 39.026 + or - 37). Lead in Au-(Cu-Te-Sn) ores is isotopically indistinguishable from that of the calc-alkalic volcanic host ( 206 Pb/ 204 Pb = 18.860 + or - 9, 207 Pb/ 204 Pb = 15.686 + or - 8, 208 Pb/ 204 Pb = 38.940 + or - 27). In contrast, the Pb in volcanic-hosted Pb-Zn-Cu-(Ag-Au) veins was derived from Paleozoic metamorphic and Miocene volcanic rocks ( 206 Pb/ 204 Pb = 18.786 + or - 5, 207 Pb/ 204 Pb = 15.686 + or - 2, 208 Pb/ 204 Pb = 38.967 + or - 9).A comparison of the Pb isotope data from southeastern Spain with published data from selected Pb-Zn deposits in southern Europe (including Les Malines, L'Argentiere, and the Alpine, Iglesiente-Sulcis, and Montagne Noire districts) indicates the importance of a metasedimentary basement as a common source of ore Pb.

Numerical study of flow, combustion and emissions characteristics in a 625 MWe tangentially fired boiler with composition of coal 70% LRC and 30% MRC

NASA Astrophysics Data System (ADS)

Sa'adiyah, Devy; Bangga, Galih; Widodo, Wawan; Ikhwan, Nur

2017-08-01

Tangential fired boiler is one of the methods that can produce more complete combustion. This method applied in Suralaya Power Plant, Indonesia. However, the boiler where supposed to use low rank coal (LRC), but at a given time must be mixed with medium rank coal (MRC) from another unit because of lack of LRC coal. Accordingly to the situation, the study about choosing the right position of LRC and MRC in the burner elevation must be investigated. The composition of coal is 70%LRC / 30%MRC where MRC will be placed at the lower (A & C - Case I)) or higher (E & G - Case II) elevation as the cases in this study. The study is carried out using Computational Fluid Dynamics (CFD) method. The simulation with original case (100%LRC) has a good agreement with the measurement data. As the results, MRC is more recommended at the burner elevation A & C rather than burner elevation E & G because it has closer temperature (880 K) compared with 100%LRC and has smaller local heating area between upper side wall and front wall with the range of temperature 1900 - 2000 K. For emissions, case I has smaller NOx and higher CO2 with 104 ppm and 15,6%. Moreover, it has samller O2 residue with 5,8% due to more complete combustion.

Baked shale and slag formed by the burning of coal beds

USGS Publications Warehouse

Rogers, G. Sherburne

1918-01-01

The baking and reddening of large masses of strata caused by the burning of coal beds is a striking feature of the landscape in most of the great western coal-bearing areas. The general character and broader effects of the burning have been described by many writers, but the fact that in places enough heat is generated to fuse and thoroughly recrystallize the overlying shale and sandstone has received less attention. Some of the natural slags thus formed simulate somewhat abnormal igneous rocks, but others consist largely of rare and little known minerals. A wide range in the mineral composition of such slags is to be expected, depending on the composition of the original sediment and the conditions of fusion and cooling. These products of purely thermal metamorphism offer a fertile field for petrologic investigation. The writer has observed the effects produced by the burning of coal beds in several localities in Montana, particularly along upper Tongue River in the southern part of the State, in the district lying southeast of the mouth of Bighorn River, and in the Little Sheep Mountain coal field north of Miles City. A number of specimens of the rock formed have been examined under the microscope, though time has not been available for a systematic examination. The writer is greatly indebted to Mr. E. S. Larsen for assistance in the study of some of the minerals.

Hydrology of coal-lease areas near Durango, Colorado

USGS Publications Warehouse

Brooks, Tom

1985-01-01

The U.S. Bureau of Land Management leases Federal lands and minerals for coal mining near Durango, Colorado. This report addresses the hydrologic suitability of those lands for coal leasing; the report describes the general hydrology of the Durango area and, more specifically, the hydrology of the Stollsteimer Creek study area 32 miles east of the Durango and the Hay Gulch study area, 12 miles southwest of Durango. The most productive aquifers in the Durango study area are Quaternary alluvium and the tertiary Animas Formation. Water wells completed in alluvium typically yield 5 to 20 gallons/min; wells completed is the Animas Formation yield as much as 50 gallons/min. Water quality in these aquifers is variable, but it generally is suitable for domestic use. The coal-bearing Cretaceous Fruitland and Menefee Formations are mined by surface methods at the Chimney Rock Mine in the Stollsteimer Creek study area and by underground methods at the National King Coal Mine in the Hay Gulch study area. Effects of surface mining in the Stollsteimer Creek area are: (1) Dewatering of an alluvial aquifer; and (2) Local degradation of alluvium water quality by spoil-pile effluent. Effects of underground mining in the Hay Gulch area are: (1) Introduction of water with greater dissolved-solids concentrations into the upper Hay Gulch alluvium from mine runoff; (2) Subsidence fracturing which could dewater streams and the alluvial aquifer. (USGS)

13. RAILROAD BRIDGE MISSISSIPPI, MONROE CO., ABERDEEN 1.5 mi. NW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. RAILROAD BRIDGE MISSISSIPPI, MONROE CO., ABERDEEN 1.5 mi. NW of Amory. St. Louis and San Francisco RR bridge. Steam locomotive and coal train cross bridge on 10 August 1921. Credit: Owned by Jack Donnell, Columbus, Ms., photographer. Copied by Sarcone Photography, Columbus, Ms. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

15. The 183Filter Plant with settling basins in January 1945. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. The 183-Filter Plant with settling basins in January 1945. The 182-B Reservoir and Pump House is on the left in the background, and the coal storage pond for the 184-B Power House is in the upper right. View is to the northwest. P-8012 - B Reactor, Richland, Benton County, WA

The enabling technology for recovery of valued components from minerals in the upper and Mid Amur region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sorokin, A.P.; Rimkevich, V.S.; Dem'yanova, L.P.

2009-05-15

Based on the physico-technical operations involved in the mineral processing technologies, the optimal production conditions are found for refractory fiber materials, aluminium, silicium, their compounds and other valued components. Ecologically safe and efficient aggregate technologies are developed for recovery of valued components from nonmetallic minerals and anthracides (brown coals).

Improved NOx emissions and combustion characteristics for a retrofitted down-fired 300-MWe utility boiler.

PubMed

Li, Zhengqi; Ren, Feng; Chen, Zhichao; Liu, Guangkui; Xu, Zhenxing

2010-05-15

A new technique combining high boiler efficiency and low-NO(x) emissions was employed in a 300MWe down-fired boiler as an economical means to reduce NO(x) emissions in down-fired boilers burning low-volatile coals. Experiments were conducted on this boiler after the retrofit with measurements taken of gas temperature distributions along the primary air and coal mixture flows and in the furnace, furnace temperatures along the main axis and gas concentrations such as O(2), CO and NO(x) in the near-wall region. Data were compared with those obtained before the retrofit and verified that by applying the combined technique, gas temperature distributions in the furnace become more reasonable. Peak temperatures were lowered from the upper furnace to the lower furnace and flame stability was improved. Despite burning low-volatile coals, NO(x) emissions can be lowered by as much as 50% without increasing the levels of unburnt carbon in fly ash and reducing boiler thermal efficiency.

Strain partitioning in the footwall of the Somiedo Nappe: structural evolution of the Narcea Tectonic Window, NW Spain

NASA Astrophysics Data System (ADS)

Gutiérrez-Alonso, Gabriel

1996-10-01

The Somiedo Nappe is a major thrust unit in the Cantabrian Zone, the external foreland fold and thrust belt of the North Iberian Variscan orogen. Exposed at the Narcea Tectonic Window are Precambrian rocks below the basal decollement of the Somiedo Nappe, which exhibit a different deformation style than the overlying Paleozoic rocks above the basal decollement. During Variscan deformation, folding and widespread subhorizontal, bedding-parallel decollements were produced in the hanging wall within the Paleozoic rocks. Vertical folding, with related axial-planar cleavage at a high angle to the decollement planes, developed simultaneously in the upper Proterozoic Narcea Slates of the footwall, below the detachment. The relative magnitude of finite strain, measured in the footwall rocks, diminishes towards the foreland. These observations indicate that (1) significant deformation may occur in the footwall of foreland fold and thrust belts, (2) the shortening mechanism in the footwall may be different from that of the hanging wall, and (3) in this particular case, the partitioning of the deformation implies the existence of a deeper, blind decollement surface contemporaneous with the first stages of the foreland development, that does not crop out in the region. This implies a significant shortening in the footwall, which must be taken into account when restoration and balancing of cross-sections is attempted. A sequential diagram of the evolution of the Narcea Tectonic Window with a minimum shortening of 85 km is proposed, explaining the complete Variscan evolution of the foreland to hinterland transition in the North Iberian Variscan orogen.

Widespread effects of middle Mississippian deformation in the Great Basin of western North America

USGS Publications Warehouse

Trexler, J.H.; Cashman, P.H.; Cole, J.C.; Snyder, W.S.; Tosdal, R.M.; Davydov, V.I.

2003-01-01

Stratigraphic analyses in central and eastern Nevada reveal the importance of a deformation event in middle Mississippian time that caused widespread deformation, uplift, and erosion. It occurred between middle Osagean and late Meramecian time and resulted in deposition of both synorogenic and postorogenic sediments. The deformation resulted in east-west shortening, expressed as east-vergent folding and east-directed thrusting; it involved sedimentary rocks of the Antler foredeep as well as strata associated with the Roberts Mountains allochthon. A latest Meramecian to early Chesterian unconformity, with correlative conformable lithofacies changes, postdates this deformation and occurs throughout Nevada. A tectonic highland-created in the middle Mississippian and lasting into the Pennsylvanian and centered in the area west and southwest of Carlin, Nevada- shed sediments eastward across the Antler foreland, burying the unconformity. Postorogenic strata are late Meramecian to early Chesterian at the base and are widespread throughout the Great Basin. The tectonism therefore occurred 20 to 30 m.y. after inception of the Late Devonian Antler orogeny, significantly extending the time span of this orogeny or representing a generally unrecognized orogenic event in the Paleozoic evolution of western North America. We propose a revised stratigraphic nomenclature for Mississippian strata in Nevada, based on detailed age control and the recognition of unconformities. This approach resolves the ambiguity of some stratigraphic names and emphasizes genetic relationships within the upper Paleozoic section. We take advantage of better stratigraphic understanding to propose two new stratigraphic units for southern and eastern Nevada: the middle Mississippian Gap Wash and Late Mississippian Captain Jack Formations.

Zaphrentis and the Zaphrentidae (Devonian; anthozoa, rugosa)

USGS Publications Warehouse

Oliver, W.A.

2007-01-01

Zaphrentis is one of the most widely used names in Paleozoic coral paleontology. Species of "Zaphrentis" have been named from every Paleozoic System except the Cambrian. Variants of the word, such as zaphrentoid, are widely used with varied meanings. Nomenclatural spinoffs are numerous: Neozaphrentis and Heterophrentis are obvious examples, but dozens of additional genera have type species that were originally described in Zaphrentis. Many paleontologists are familiar with the word but few really know what it means. Zaphrentis (as a subgenus) and five new species were named in 1820, based on corals from the Falls of the Ohio River between Louisville, Kentucky, and Clarksville, Indiana. Descriptions were minimal, none was illustrated, and no specimens were preserved as types. Nominal species of "Zaphrentis" proliferated for over 100 years before a redescription based on Falls specimens was published (1938), the probable source beds recognized (1942), a neotype selected (1965) and adequately described and illustrated (1981). At this time, I recognize only four zaphrentid genera: Zaphrentis (middle Eifelian), Heliophyllum (middle Emsian through Givetian), Aemulophyllum (middle Emsian), and Cyathocylindrium (lower Emsian?; middle Emsian through Eifelian). All four genera seem to have originated in the Eastern Americas Biogeographic Realm. Heliophyllum is the most common, has the longest stratigraphic range, and is the only one known to occur outside of its area of origin. Heliophyllum modicum n. sp., once discussed as a possible Zaphrentis, is described and compared with both the type species of Zaphrentis and other Heliophyllum species. A single coral specimen from the Indian Cove Formation (upper Pragian or lower Emsian), Gaspe??, Quebec, is considered the earliest known zaphrentid and is described as Cyathocylindrium? n. sp.

Origin and structural development of the LaSalle Arch, Louisiana

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawless, P.N.

1990-05-01

The LaSalle arch is a basement high separating the Louisiana and Mississippi interior salt basins. Using reflection seismic data, an area located on the southern end of the LaSalle arch was shown to be composed of relict Paleozoic continental crust that was left behind and partially rifted during the breakup of Pangea during the Triassic. Rifting preferentially occurred to the north of a Paleozoic thrust fault nose, and crustal extension took place in a northeast-southwest direction. The LaSalle arch, as seen in post-Triassic stratigraphy, formed by a two-part process. The western limb developed syndepositionally due to differential subsidence, and themore » eastern limb developed due to relative regional tilting to the east after deposition of the Claibornian Sparta Formation. The LaSalle arch acted as only a minor impediment to sediment transport with a very low relief except during the Tayloran Stage of the Upper Cretaceous. A single truncational unconformity in post-Triassic stratigraphy is present in the Taylora Demopolis Formation, indicating a period of relatively major uplift by the LaSalle arch. This contrast, with the Sabine arch in eastern Texas; the Sabine arch experienced uplift during the Eagle Fordian and Sabinian stages. A recently proposed hypothesis calling for overthrusting in the Western Cordillera as the mechanism for uplift on the Sabine arch cannot explain movement of the LaSalle arch because horizontal stress would predict synchronous uplift of basement highs. A more satisfactory uplift mechanism calls upon lateral heat flow from the mantle as the driving force for uplift.« less

Petrology and geochemistry of meta-ultramafic rocks in the Paleozoic Granjeno Schist, northeastern Mexico: Remnants of Pangaea ocean floor

NASA Astrophysics Data System (ADS)

Torres-Sánchez, Sonia Alejandra; Augustsson, Carita; Jenchen, Uwe; Rafael Barboza-Gudiño, J.; Alemán Gallardo, Eduardo; Ramírez Fernández, Juan Alonso; Torres-Sánchez, Darío; Abratis, Michael

2017-08-01

The Granjeno Schist is a meta-volcanosedimentary upper Paleozoic complex in northeastern Mexico. We suggest different tectonic settings for metamorphism of its serpentinite and talc-bearing rocks based on petrographic and geochemical compositions. According to the REE ratios (LaN/YbN = 0.51 -20.0 and LaN/SmN = 0.72-9.1) and the enrichment in the highly incompatible elements Cs (0.1 ppm), U (2.8 ppm), and Zr (60 ppm) as well as depletion in Ba (1 - 15 ppm), Sr (1 -184 ppm), Pb (0.1 -14 ppm), and Ce (0.1 -1.9 ppm) the rocks have mid-ocean ridge and subduction zones characteristics. The serpentinite contains Al-chromite, ferrian chromite and magnetite. The Al-chromite is characterized by Cr# of 0.48 to 0.55 suggesting a MORB origin, and Cr# of 0.93 to 1.00 for the ferrian chromite indicates a prograde metamorphism. We propose at least two serpentinization stages of lithospheric mantle for the ultramafic rock of the Granjeno Schist, (1) a first in an ocean-floor environment at sub-greenschist to greenschist facies conditions and (2) later a serpentinization phase related to the progressive replacement of spinel by ferrian chromite and magnetite at greenschist to low amphibolite facies conditions during regional metamorphism. The second serpentinization phase took place in an active continental margin during the Pennsylvanian. We propose that the origin of the ultramafic rocks is related to an obduction and accretional event at the western margin of Pangea.

Distribution of rubidium, strontium, and zirconium in tuff from two deep coreholes at Yucca Mountain, Nevada

USGS Publications Warehouse

Spengler, Richard W.; Peterman, Zell E.; ,

1991-01-01

Variations in concentrations of trace elements Rb, Sr, and Zr within the sequence of high-silica tuff and dacitic lava beneath Yucca Mountain reflect both primary composition and secondary alteration. Rb and K concentrations have parallel trends. Rb concentrations are significantly lower within intervals containing zeolitic nonwelded to partially welded and bedded tuffs and are higher in thick moderately to densely welded zones. Sr concentrations increase with depth from about 30 ppm in the Topopah Spring Member of the Paintbrush Tuff to almost 300 ppm in the older tuffs. Zr concentrations are about 100 ppm in the Topopah Spring Member and also increase with depth to about 150 ppm in the Lithic Ridge Tuff and upper part of the older tuffs. Conspicuous local high concentrations of Sr in the lower part of the Tram Member, in the dacite lava, and in unit c of the older tuffs in USW G-1, and in the densely welded zone of the Bullfrog Member in USW GU-3/G-3 closely correlate with high concentrations of less-mobile Zr and may reflect either primary composition or elemental redistribution resulting largely from smectitic alteration. Initial 87Sr/86Sr values from composite samples increase upward in units above the Bullfrog Member of the Crater Flat Tuff. The progressive tenfold increase in Sr with depth coupled with the similarity of initial 87Sr/86Sr values within the Bullfrog Member and older units to those of Paleozoic marine carbonates are consistent with a massive influx of Sr from water derived from a Paleozoic carbonate aquifer.

The Potential for Prophyry Copper-Molybdenum Deposits in the Eastern United States

USGS Publications Warehouse

Schmidt, Robert Gordon

1978-01-01

Several significant porphyry-type deposits of Paleozoic age are known in New England and eastern Canada. Disseminated copper-molybdenum deposits of Paleozoic age are in the Southeastern United States, and copper is produced from porphyry-type deposits of both Precambrian and Paleozoic age in eastern Canada. Although these old deposits are surely less abundant than those in Cenozoic and Tertiary porphyry belts, the known Precrambrian and Paleozoic deposits in Eastern North America appear to be valid exploration targets. The difficult of 'prospecting in drift-covered and saprolite-mantled terrains suggests that all such deposits probably have not been discovered. Although such deposits are more costly to discover in this region than a massive sulfide deposit, the total amount of copper in even a medium-sized porphyry copper deposit is much greater than in most massive sulfide deposits. This report summarizes current knowledge of porphyry copper-molybdenum-type deposits in the Eastern United States and suggests more favorable areas for mineral exploration. Selected Canadian deposits are discussed because of their bearing on planning exploration in this country.

Formation of modern and Paleozoic stratiform barite at cold methane seeps on continental margins

USGS Publications Warehouse

Torres, M.E.; Bohrmann, G.; Dube, T.E.; Poole, F.G.

2003-01-01

Stratiform (bedded) Paleozoic barite occurs as large conformable beds within organic- and chert-rich sediments; the beds lack major sulfide minerals and are the largest and most economically significant barite deposits in the geologic record. Existing models for the origin of bedded barite fail to explain all their characteristics: the deposits display properties consistent with an exhalative origin involving fluid ascent to the seafloor, but they lack appreciable polymetallic sulfide minerals and the corresponding strontium isotopic composition to support a hydrothermal vent source. A new mechanism of barite formation, along structurally controlled sites of cold fluid seepage in continental margins, involves barite remobilization in organic-rich, highly reducing sediments, transport of barium-rich fluids, and barite precipitation at cold methane seeps. The lithologic and depositional framework of Paleozoic and cold seep barite, as well as morphological, textural, and chemical characteristics of the deposits, and associations with chemosymbiotic fauna, all support a cold seep origin for stratiform Paleozoic barite. This understanding is highly relevant to paleoceanographic and paleotectonic studies, as well as to economic geology.

Community heterogeneity of Early Pennsylvanian peat mires

USGS Publications Warehouse

Gastaldo, Robert A.; Stevanovic-Walls, I. M.; Ware, W.N.; Greb, S.F.

2004-01-01

Reconstructions of Pennsylvanian coal swamps are some of the most common images of late Paleozoic terrestrial ecosystems. All reconstructions to date are based on data from either time-averaged permineralized peats or single-site collections. An erect, in situ Early Pennsylvanian forest preserved above the Blue Creek Coal, Black Warrior Basin, Alabama, was sampled in 17 localities over an area of >0.5 km2, resulting in the first temporally and spatially constrained Pennsylvanian mire data set. This three-tiered forest was heterogeneous. Lycopsid and calamitean trees composed the canopy, and lepidodendrids, Lepidophloios, and sigillarians grew together at most sites. More juvenile than mature lycopsid biomass occurs in the forest-floor litter, indicating a mixed-age, multicohort canopy. Pteridophytes (tree fern) and pteridosperms (seed fern) dominated as understory shrubs, whereas sphenophyllaleans, pteridophytes, and pteridosperms composed the ground-cover and liana tier. The proportion of canopy, understory, and ground-cover biomass varied across the forest. Low proportions of ground-cover and liana taxa existed where canopy fossils accounted for >60% of the litter. There is a distinct spatial clustering of sites with more or less understory (or ground cover) where canopy contribution was <60%. Where canopy biomass was low (<50%), understory shrubs contributed more biomass, indicative of light interception and/or competition strategies. Sphenopteris pottsvillea, a ubiquitous ground-cover plant, is abundant in all sites except one, where pteridosperm creepers and lianas dominate the litter, interpreted to indicate total suppression of other ground-cover growth. Ecological wet-dry gradients identified in other Pennsylvanian swamps do not exist in the Blue Creek mire, with the interpreted wettest (Lepidophloios), driest (Sigillaria), and intermediate (Lepidodendron sensu latu) taxa coexisting in most assemblages. ?? 2004 Geological Society of America.

Tethyan evolution of central Asia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sengor, A.M.C.

1990-05-01

The study area extends from the eastern shores of the Caspian Sea in the west to the Helan Shan and Longmen Shan in the east and from about 40{degree}N parallel in the north to the neo-Tethyan sutures in the south, thus including what is called Middle Asia in the Soviet literature. In the region thus delineated lies the boundary between the largely late Paleozoic core of Asia (Altaids) and the Tethyside superorogenic complex. This boundary passes through continental objects that collided with nuclear Asia in the late Paleozoic to terminate its Altaid evolution. Subduction to the south of some ofmore » these had commenced before they collided (e.g., Tarim in the Kuen-Lun), in others later (e.g., South Ghissar area west of Pamirs). This subduction 1ed, in the late Paleozoic, to the opening of marginal basins, at least one of which may be partly extant (Tarim). Giant subduction accretion complexes of Paleozoic to earliest Triassic age dominate farther south in the basement of Turan (mainly in Turkmenian SSR) and in the Kuen-Lun/Nan Shan ranges. No discrete continental collisions or any continental basement in these regions could be unequivocally recognized contrary to most current interpretations. Magmatic arcs that developed along the southern margin of Asia in the late Paleozoic to early Mesozoic grew atop these subduction-accretion complexes and record a gradual southerly migration of magmatism through time. Subduction also dominated the northern margin of Gondwanaland between Iran and China in late Paleozoic time, although the record in Afghanistan and northwest Tibet is scrappy. It led to back-arc basin formation, which in Iran and Oman became neo-Tethys and, in at least parts of central Asia, the Waser-Mushan-Pshart/Banggong Co-Nu Jiang ocean. This ocean was probably connected with the Omani part of the neo-Tethys via the Sistan region.« less

Geology and Mineral Resources of the North Absaroka Wilderness and Vicinity, Park County, Wyoming, with Sections on Mineralization of the Sunlight Mining Region and Geology and Mineralization of the Cooke City Mining District, and a Section on Aeromagnetic Survey

USGS Publications Warehouse

Nelson, Willis H.; Prostka, Harold J.; Williams, Frank E.; Elliott, James E.; Peterson, Donald L.

1980-01-01

SUMMARY The North Absaroka Wilderness is approximately 560 square miles (1,450 km 2 ) of rugged scenic mountainous terrain that adjoins the eastern boundary of Yellowstone National Park in northwestern Wyoming. The area was studied during 1970, 1971, and 1972 by personnel of the U. S. Geological Survey and the U. S. Bureau of Mines to evaluate its mineral-resource potential as required by the Wilderness Act of 1964. This evaluation is based on a search of the literature courthouse and production records, geologic field mapping, field inspection of claims and prospects, analyses of bedrock and stream-sediment samples, and an aeromagnetic survey. The North Absaroka Wilderness is underlain almost entirely by andesitic and basaltic volcanic rocks of Eocene age. These volcanics rest on deformed sedimentary rocks of Paleozoic and, locally, of Mesozoic age that are exposed at places along the northern and eastern edges of the wilderness. Dikes and other igneous intrusive bodies cut both the volcanic and sedimentary rocks. A nearly flat detachment fault, the Heart Mountain fault, and a related steep break-away fault have displaced middle and upper Paleozoic rocks and some of the older part of the volcanic sequence to the southeast. A much greater thickness of volcanic rocks was found to be involved in Heart Mountain faulting than had previously been recognized; however, most of the volcanic rocks and many of the intrusives were emplaced after Heart Mountain faulting. Local folding and high-angle faulting in mid-Eocene time have deformed all but the youngest part of the volcanic sequence in the southeastern part of the wilderness. This deformation is interpreted as the last pulse of Laramide orogeny. The results of this study indicate that the mineral-resource potential of the wilderness is minimal. Bentonite, petroleum, low-quality coal, and localized deposits of uranium and chromite have been produced in the surrounding region from rocks that underlie the volcanic rocks; but such deposits, if present in the wilderness, would be too deeply buried, too small, or too sporadically distributed to be profitably located and exploited. Copper and gold mines and prospects are present on the fringes of the wilderness, but otherwise the area seems to be devoid of economically valuable concentrations of metallic minerals. No surface evidence of geothermal-energy potential was found. Known mineral deposits in the vicinity of the North Absaroka Wilderness are associated with intrusive rocks. From the Cooke City mining district, just north of the wilderness, replacement deposits in Upper Cambrian carbonate rocks may extend a short distance into the north edge of the wilderness, In the Sunlight mining region, an enclave nearly surrounded by the wilderness, mineralization occurs in veins and is disseminated in volcanic and plutonic rocks. Richer concentrations of metallic minerals may occur in carbonate rocks adjacent to intrusive bodies at depth beneath the volcanic rocks in the Sunlight region. A few small intrusive bodies occur in the wilderness, but no significant associated mineralization was detected. Aeromagnetic data indicate that other intrusives not exposed by erosion may occur in the wilderness; however, no significant metamorphism or alteration is evident at the surface to indicate their presence. Although most of the rocks of the wilderness are of igneous origin, they are all so old (Eocene) that it is unlikely that they retain any original heat. The Pleistocene rhyolitic ash-flow tuffs in the southwestern part of the wilderness were erupted from sources in Yellowstone National Park just to the west; however, in the wilderness these tuffs are too thin to contain any residual heat.

Eocene bituminous coal deposits of the Claiborne group, Webb County, Texas

USGS Publications Warehouse

Hook, Robert W.; Warwick, Peter D.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

2011-01-01

Two bituminous coal zones, the San Pedro and the Santo Tomas, in the middle Eocene Claiborne Group of Webb County, south Texas (Figure 1), are among the coal resources that are not evaluated quantitatively as part of the current Gulf Coastal Plain coal resource assessment. Coal beds within these zones were mined by underground methods northwest of Laredo until 1939 and have been intermittently mined at the surface since 1979. These coals have long been regarded as unique within the Gulf Coast Tertiary coal-bearing section because they are high-volatile C bituminous in rank and because their physical characteristics resemble upper Carboniferous cannel coals of the Appalachians and Europe.Discontinuous exposures of the Santo Tomas and the underlying San Pedro coal zone extend northwestward from Dolores for approximately 15 to 21 mi along the breaks of the Rio Grande and its tributaries in Webb County (Figure 1). This part of south Texas lies along the southwestern flank of the Rio Grande Embayment, which extends south and southeastwardly through the Mexican States of Coahuila, Nuevo León, and Tamaulipas (Figure 1). Within the embayment, the lower to middle part of the Claiborne Group consists of marine mudstones (Reklaw Formation) in the east and northeast and sandstones and mudstones (Bigford Formation) in the south and southwest (Figure 2). The marine mudstones coarsen upward into fluvial-deltaic sandstones (Queen City Sand) that prograded gulfward across eastern and central Texas (Guevara and Garcia, 1972). To the west and southwest, the interval overlying the Bigford Formation becomes less sandy, and claystones (El Pico Clay) predominate. Although the San Pedro coal zone has been placed traditionally near the top of the Bigford Formation and the Santo Tomas coal zone near the base of the El Pico Clay, recent work has failed to validate a mappable contact between these formations (Warwick and Hook, 1995). The coal beds dip northeast at less than 2 degrees towards the synclinal axis of the basin.The following summary is based upon published and unpublished reports; drillhole records (geophysical logs, descriptions of cores and cuttings); coal-quality data obtained from the permit files of the Railroad Commission of Texas and recent sampling by the U.S. Geological Survey (USGS); a preliminary review of proprietary data acquired recently by the USGS; and field work conducted by the USGS since 1994. A total of approximately 200 drillhole records was examined.

Analysis of Degree of Similarity among Crude Oils, the Upper and the Lower Crust, Organic Matter, Clays, and Different Caustobioliths by the Content of Their Main and Trace Elements

NASA Astrophysics Data System (ADS)

Rodkin, Mikhail; Punanova, Svetlana

2016-04-01

The goal of this research was to estimate, based on the content of Trace Elements, the level of contribution of the lower and the upper crust as well as the organic matter into ontogenesis of hydrocarbons. The analysis of degree of similarity of the main and trace element (TE) content among the upper and lower continental crust, clays, organic matter, and different caustobioliths (oil, coal, oil-and-black shales) is performed by calculating coefficients of correlation of logarithms of concentrations of a large number of different chemical elements. Different oils from a number of oil bearing provinces in Russia and from the volcanic caldera Uzon (Kamchatka, Russia) were examined. It has been shown that the content of main elements and TEs of coals and oil-and-black shales is better correlated with the chemical composition of the upper crust, while the TE content of oils correlates better with the composition of the lower continental crust. The TE content of oils correlates with the chemical content of living organisms but the correlation in the most cases is weaker than the one with the lower crust. The results of the examination of different samples from the same oil-bearing province were found to be similar. The mean results for different oil-bearing provinces can vary considerably. The results of the examination of young oil from the Uzon volcanic caldera were found to be rather specific and different from the other oils. We also suggest a set of a small number of "characteristic" elements (Cs, Rb, K, U, V, Cr and Ni), which allows to compare the degree of similarity between an oil sample and upper or lower continental crust using only a few chemical elements. Some interpretation of the results is presented.

Intrusive rocks of the Holden and Lucerne quadrangles, Washington; the relation of depth zones, composition, textures, and emplacement of plutons

USGS Publications Warehouse

Cater, Fred W.

1982-01-01

The core of the northern Cascade Range in Washington consists of Precambrian and upper Paleozoic metamorphic rocks cut by numerous plutons, ranging in age from early Triassic to Miocene. The older plutons have been eroded to catazonal depths, whereas subvolcanic rocks are exposed in the youngest plutons. The Holden and Lucerne quadrangles span a -sizeable and representative part of this core. The oldest of the formations mapped in these quadrangles is the Swakane Biotite Gneiss, which was shown on the quadrangle maps as Cretaceous and older in age. The Swakane has yielded a middle Paleozoic metamorphic age, and also contains evidence of zircon inherited from some parent material more than 1,650 m.y. old. In this report, the Swakane is assigned an early Paleozoic or older age. It consists mostly of biotite gneiss, but interlayered with it are scattered layers and lenses of hornblende schist and gneiss, clinozoisite-epidote gneiss, and quartzite. Thickness of the Swakane is many thousands of meters, and the base is not exposed. The biotite gneiss is probably derived from a pile of siliceous volcanic rocks containing scattered sedimentary beds and basalt flows. Overlying the Swakane is a thick sequence of eugeosynclinal upper Paleozoic rocks metamorphosed to amphibolite grade. The sequence includes quartzite and thin layers of marble, hornblende schist and gneiss, graphitic schist, and smaller amounts of schist and gneiss of widely varying compositions. The layers have been tightly and complexly folded, and, in places, probably had been thrust over the overlying Swakane prior to metamorphism. Youngest of the supracrustal rocks in the area are shale, arkosic sandstone, and conglomerate of the Paleocene Swauk Formation. These rocks are preserved in the Chiwaukum graben, a major structural element of the region. Of uncertain age, but possibly as old as any of the intrusive rocks in the area, are small masses of ultramafic rocks, now almost completely altered to serpentine. These occur either as included irregular masses in later intrusives or as tectonically emplaced lenses in metamorphic rocks. Also of uncertain age but probably much younger, perhaps as young as Eocene, are larger masses of hornblendite and hornblende periodotite that grade into hornblende gabbro. These are exposed on the surface and in the underground workings of the Holden mine. Oldest of the granitoid intrusives are the narrow, nearly concordant Dumbell Mountain plutons, having a radiometric age of about 220 m.y. They consist of gneissic hornblende-quartz diorite and quartz diorite gneiss. Most contacts consist of lit-par-lit zones, but some are gradational or more rarely sharp. The plutons are typically catazonal. Closely resembling the Dumbell Mountain plutons in outcrop appearance, but differing considerably in composition, are the Bearcat Ridge plutons. These consist of gneissic quartz diorite and granodiorite. The Bearcat Ridge plutons are not in contact with older dated plutons, but because their textural and structural characteristics so closely resemble those of the Dumbell Mountain plutons, they are considered to be the same age. Their composition, however, is suggestive of a much younger age. Cutting the Dumbell Mountain plutons is the Leroy Creek pluton, consisting of gneissic biotite-quartz diorite and trondjhemite. The gneissic foliation in the Leroy Creek is characterized by a strong and pervasive swirling. Cutting both the Dumbell Mountain and Leroy Creek plutons are the almost dikelike Seven-fingered Jack plutons. These range in composition from gabbro to quartz diorite; associated with them are contact complexes of highly varied rocks characterized by gabbro and coarse-grained hornblendite. Most of the rocks are gneissic, but some are massive and structureless. Radiometric ages by various methods range from 100 to 193 m.y. Dikes, sills, small stocks, and irregular clots of leucocratic quartz diorite and granodiorite are abundant in t

Vehicle autonomous localization in local area of coal mine tunnel based on vision sensors and ultrasonic sensors

PubMed Central

Yang, Wei; You, Kaiming; Li, Wei; Kim, Young-il

2017-01-01

This paper presents a vehicle autonomous localization method in local area of coal mine tunnel based on vision sensors and ultrasonic sensors. Barcode tags are deployed in pairs on both sides of the tunnel walls at certain intervals as artificial landmarks. The barcode coding is designed based on UPC-A code. The global coordinates of the upper left inner corner point of the feature frame of each barcode tag deployed in the tunnel are uniquely represented by the barcode. Two on-board vision sensors are used to recognize each pair of barcode tags on both sides of the tunnel walls. The distance between the upper left inner corner point of the feature frame of each barcode tag and the vehicle center point can be determined by using a visual distance projection model. The on-board ultrasonic sensors are used to measure the distance from the vehicle center point to the left side of the tunnel walls. Once the spatial geometric relationship between the barcode tags and the vehicle center point is established, the 3D coordinates of the vehicle center point in the tunnel’s global coordinate system can be calculated. Experiments on a straight corridor and an underground tunnel have shown that the proposed vehicle autonomous localization method is not only able to quickly recognize the barcode tags affixed to the tunnel walls, but also has relatively small average localization errors in the vehicle center point’s plane and vertical coordinates to meet autonomous unmanned vehicle positioning requirements in local area of coal mine tunnel. PMID:28141829

Vehicle autonomous localization in local area of coal mine tunnel based on vision sensors and ultrasonic sensors.

PubMed

Xu, Zirui; Yang, Wei; You, Kaiming; Li, Wei; Kim, Young-Il

2017-01-01

This paper presents a vehicle autonomous localization method in local area of coal mine tunnel based on vision sensors and ultrasonic sensors. Barcode tags are deployed in pairs on both sides of the tunnel walls at certain intervals as artificial landmarks. The barcode coding is designed based on UPC-A code. The global coordinates of the upper left inner corner point of the feature frame of each barcode tag deployed in the tunnel are uniquely represented by the barcode. Two on-board vision sensors are used to recognize each pair of barcode tags on both sides of the tunnel walls. The distance between the upper left inner corner point of the feature frame of each barcode tag and the vehicle center point can be determined by using a visual distance projection model. The on-board ultrasonic sensors are used to measure the distance from the vehicle center point to the left side of the tunnel walls. Once the spatial geometric relationship between the barcode tags and the vehicle center point is established, the 3D coordinates of the vehicle center point in the tunnel's global coordinate system can be calculated. Experiments on a straight corridor and an underground tunnel have shown that the proposed vehicle autonomous localization method is not only able to quickly recognize the barcode tags affixed to the tunnel walls, but also has relatively small average localization errors in the vehicle center point's plane and vertical coordinates to meet autonomous unmanned vehicle positioning requirements in local area of coal mine tunnel.

Geologic setting and water quality of selected basins in the active coal-mining areas of Ohio, 1987-88

USGS Publications Warehouse

Sedam, A.C.

1991-01-01

This report presents hydrologic data from selected drainage basins in the active coal-mining areas of Ohio from July 1987 through October 1988. The study area is mostly within the unglaciated part of eastern Ohio along the western edge of the Appalachian Plateaus physiographic province. The 1987-88 work is the second phase of a 7-year study to assess baseline water quality in Ohio's coal region. The data collection network consisted of 41 long-term surface-water sites in 21 basins. The sites were measured and sampled twice yearly at low flow. In addition, six individual basins (three each year) selected for a more detailed representation of surface-water and ground-water quality. In 1987, the Sandy Creek, Middle Tuscarawas River and Sugar Creek, and Lower Tuscarawas River basins were chosen. In 1988, the Short and Wheeling Creeks, Upper Wills Creek, and Upper Raccoon Creek basins were chosen. Because of their proximity to the glaciated region and outwash drainage, the basins studied intensively in 1987 contain more shallow productive aquifers than do the basins studied in detail for 1988, in which shallow ground-water sources are very localized. Chemical analyses for 202 surface-water and 24 ground-water samples are presented. For field measurements made at surface-water sites, the specific conductance ranged from 295 to 3150 ? S/cm (microsiemens per centimeter at 25 degrees Celsius). For pH, the range was 2.8 to 8.6. Alkalinity ranged from 5 to 305 mg/L (milligrams per liter) as CaCO3.

Distribution and variation of the inorganic fraction of Devonian to Bashkirian black shales in the north-western part of the Dniepr-Donets Basin, Ukraine

NASA Astrophysics Data System (ADS)

Wegerer, Eva; Sachsenhofer, Reinhard; Misch, David; Aust, Nicolai

2016-04-01

Mineralogical data of 112 core samples from 12 wells are used to investigate lateral and vertical variations in the lithofacies of Devonian to Bashkirian black shales in the north-western part of the Dniepr-Donets-Basin. Sulphur and carbonate contents as well as organic geochemical parameters, including TOC and Hydrogen Index have been determined on the same sample set within the frame of an earlier study (Sachsenhofer et al. 2010). This allows the correlation of inorganic and organic composition of the black shales. Aims of the study are to distinguish between detrital and authigenic minerals, to relate the lithofacies of the black shales with the tectono-stratigraphic sequences of the Dniepr-Donets Basin, to contribute to the reconstruction of the depositional environment and to relate diagenetic processes with the thermal history of the basin. Mineral compositions were determined primarily using XRD-measurements applying several measurement procedures, e.g. chemical and temperature treatment, and specific standards. Major differences exist in the mineralogical composition of the black shales. For example, clay mineral contents range from less than 20 to more than 80 Vol%. Kaolinite contents are significantly higher in rocks with a Tournaisian or Early Visean age than in any other stratigraphic unit. This is also true for two Lower Visean coal samples from the shallow north-westernmost part of the basin. Chlorite contents reach maxima in uppermost Visean and overlying rocks. Quartz contents are often high in Upper Visean rocks and reach maxima in Bashkirian units. Feldspar-rich rocks are observed in Devonian sediments from the north-western part of the study area and may reflect the proximity to a sediment source. Carbonate contents are typically low, but reach very high values in some Tournaisian, Lower Visean and Serpukhovian samples. Pyrite contents reach maxima along the basin axis in Tournaisian and Visean rocks reflecting anoxic conditions. Mixed layer minerals are dominated by illite. Their presence in samples from depth exceeding 5 km reflects the low thermal overprint of Paleozoic rocks in the north-western Dniepr-Donets-Basin.

Reinterpretation of the stratigraphy and structure of the Rancho Las Norias area, central Sonora, Mexico

USGS Publications Warehouse

Page, W.R.; Harris, A.G.; Poole, F.G.; Repetski, J.E.

2003-01-01

New geologic mapping and fossil data in the vicinity of Rancho Las Norias, 30 km east of Hermosillo, Sonora, Mexico, show that rocks previously mapped as Precambrian instead are Paleozoic. Previous geologic maps of the Rancho Las Norias area show northeast-directed, southwest-dipping reverse or thrust faults deforming both Precambrian and Paleozoic rocks. The revised stratigraphy requires reinterpretation of some of these faults as high-angle normal or oblique-slip faults and the elimination of other faults. We agree with earlier geologic map interpretations that compressional structures have affected the Paleozoic rocks in the area, but our mapping suggests that the direction of compression is from southeast to northwest. Published by Elsevier Ltd.

Hydrocarbon source rock potential of the Karoo in Zimbabwe

NASA Astrophysics Data System (ADS)

Hiller, K.; Shoko, U.

1996-07-01

The hydrocarbon potential of Zimbabwe is tied to the Karoo rifts which fringe the Zimbabwe Craton, i.e. the Mid-Zambezi basin/rift and the Mana Pools basin in the northwest, the Cabora Bassa basin in the north and the Tuli-Bubye and Sabi-Runde basins in the south. Based on the geochemical investigation of almost one thousand samples of fine clastic Karoo sediments, a concise source rock inventory has been established showing the following features. No marine source rocks have been identified. In the Mid-Zambezi area and Cabora Bassa basin, the source rocks are gas-prone, carbonaceous to coaly mudstones and coal of Lower Karoo age. In the Cabora Bassa basin, similar gas-prone source rocks occur in the Upper Karoo (Angwa Alternations Member). These kerogen type III source rocks are widespread and predominantly immature to moderately mature. In the southern basins, the Lower Karoo source rocks are gas-prone; in addition some have a small condensate potential. Most of the samples are, however, overmature due to numerous dolerite intrusions. Samples with a mixed gas, condensate and oil potential (mainly kerogen types II and III) were identified in the Lower Karoo (Coal Measure and Lower Madumabisa Mudstone Formations) of the Mid-Zambezi basin, and in the Louver Karoo (Mkanga Formation) and Upper Karoo (Upper Angwa Alternations Member Formation) of the Cabora Bassa basin. The source rocks, with a liquid potential, are also immature to moderately mature and were deposited in swamp, paludal and lacustrine environments of limited extent.

Crew Earth Observations (CEO) taken during Expedition Six

NASA Image and Video Library

2003-02-01

ISS006-E-28016 (February 2003) --- The Coal Sack Nebula (bottom center), the Southern Cross (lower right), and the two prominent stars in the upper left, which are the two prominent stars of the southern constellation Centaurus, are visible in this view photographed by astronaut Donald R. Pettit, Expedition Six NASA ISS science officer, on board the International Space Station (ISS).

PROPOSED PROCEDURE FOR DERIVATION OF REGULATORY VALUES FOR CARCINOGENIC AIRBORNE POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) BASED ON COAL TAR PITCH (CTP) VOLATILES

EPA Science Inventory

A procedure for estimating upper bound lifetime human cancer risk from air levels of 6 common carcinogenic PAHs, termed "PAHs of concern", is proposed. These PAHs are benzo(a)pyrene, benz(a)anathracene, benzo(k)flouranthene, indeno(1,2,3-c,d)pyrene and chrysene. In application,...

A geologic history of the north-central Appalachians, part 3. The Alleghany orogeny

USGS Publications Warehouse

Faill, R.T.

1998-01-01

The north-central Appalachians occupy a critical position within the 3000+ km-long Appalachian orogen, lying southwest of the boundary between the central and northern Appalachians (CNAB). The one-billion-year-long history of tectonic activity in eastern Laurentia includes the creation and evolution of the Appalachian orogen during the Paleozoic and the Mesozoic transformation of the orogen into a passive margin during Pangea's disassembly. A most important ingredient in the evolution of the orogen was the Alleghany orogeny, which was driven by the convergence and collision between Laurentia (Laurussia) and West Gondwana (Africa). The Alleghany orogeny in the central and southern Appalachians was a de??collement tectonism that involved a larger part of eastern Laurentia than had the previous three orogenies. The fundamental element was a very low-angle thrust (de??collement) that originated in mid-crustal levels east of the presently-exposed Appalachians and rose westwardly to progressively higher levels in the upper crust and the supra-crustal Paleozoic section. Alleghany deformation was widely developed in the hanging-wall block (allochthon), primarily in the form of thrust faults and fold-and-thrust structures, both of which splayed upward from the basal de??collement. The youngest manifestations of the Alleghany orogeny were northeast-trending strike-slip faults and dextral shear zones in the Piedmont. In the north-central Appalachians, the exposed allochthon consists of two parts: the sedimentary externides (Appalachian Plateau and Valley and Ridge provinces) and the crystalline externides (Reading Prong, Blue Ridge belt, and Piedmont province). Long, thrust-cored anticlines predominate in the sedimentary externides. A widespread layer-parallel shortening preceded the folding; it is largely coaxial with the folding but extends considerably farther to the northwest toward the craton. It is hypothesized that the folding developed in reverse order, sequentially from the northwest to the southeast The crystalline externides are dominated by low-angle thrust faults and upright folds trending east-northeast The first-order Valley and Ridge folds on the northwest side acted as a buttress and diverted the crystalline externides rocks north-northwestwardly, onto the topographic low area over the Anthracite region. This thrusting of the crystalline externides caused anthracitization of the coals within the Pennsylvanian rocks there. Metamorphism and magmatism were significant events during the earlier phase of the Alleghany orogeny in the southern Appalachians. Whatever magmatism and medium-to high-grade metamorphism developed in the north-central Appalachians are in the covered internides to the southeast. The Alleghany orogeny of the north-central Appalachians occurred during the Early Permian. Erosion of anticlinal crests probably began as the folds grew, with accumulation of this locally-derived sediment in the intervening synclines. A regional alluvial plain coalesced above the partially-eroded externides structures as erosion of the pre-Alleghany highland and the Alleghany hinterland mountains continued to the southeast, spreading sediment to the northwest. This erosion and northwest transport probably persisted, with diminishing intensity, throughout the remainder of the Permian and into the Mesozoic, and changed only with the beginning of crustal extension during the Late Triassic.

Geologic map of the Vail East quadrangle, Eagle County, Colorado

USGS Publications Warehouse

Kellogg, Karl S.; Bryant, Bruce; Redsteer, Margaret H.

2003-01-01

New 1:24,000-scale geologic mapping along the Interstate-70 urban corridor in western Colorado, in support of the State/USGS Cooperative Geologic Mapping Project, is contributing to a more complete understanding of the stratigraphy, structure, tectonic evolution, and hazard potential of this rapidly developing region. The 1:24,000-scale Vail East quadrangle straddles the Gore fault system, the western structural boundary of the Gore Range. The Gore fault system is a contractional structure that has been recurrently active since at least the early Paleozoic and marks the approximate eastern boundary of the Central Colorado trough, a thick late Paleozoic depocenter into which thousands of meters of clastic sediment were deposited from several uplifts, including the ancestral Front Range. The Gore fault was active during both the late Paleozoic and Upper Cretaceous-lower Tertiary (Laramide) deformations. In addition, numerous north-northwest faults that cut the crystalline rocks of the Gore Range were active during at least 5 periods, the last of which was related to Neogene uplift of the Gore Range and formation of the northern Rio Grande rift. Early Proterozoic crystalline rocks underlie the high Gore Range, north and east of the Gore fault system. These rocks consist predominantly of migmatitic biotite gneiss intruded by mostly granitic rocks of the 1.667-1.750 Ma Cross Creek batholith, part of the 1,667-1,750 Ma Routt Plutonic Suite (Tweto, 1987). Southwest of the Gore fault, a mostly gently south-dipping sequence of Pennsylvanian Mimturn Formation, as thick as 1,900 m, and the Permian and Pennsylvanian Maroon Formation (only the basal several hundred meters are exposed in the quadrangle)were shed from the ancestral Front Range and overlie a thin sequence of Devonian and Cambrian rocks. The Minturn Formation is a sequence of interlayered pink, maroon, and gray conglomerate, sandstone, shale, and marine limestone. The Maroon Formation is mostly reddish conglomerate and sandstone. Glacial till of both the middle Pleistocene Bull Lake and late Pleistocene Pinedale glaciations are well exposed along parts of the Gore Creek valley and its tributaries, although human development has profoundly altered the outcrop patterns along the Gore Creek valley bottom. Landslides, some of which are currently active, are also mapped.

Geological development and Phanerozoic crustal accretion in the western segment of the southern Tien Shan (Kyrgyzstan, Uzbekistan and Tajikistan)

NASA Astrophysics Data System (ADS)

Brookfield, M. E.

2000-12-01

The Tien Shan form a high intracontinental mountain belt, lying north of the main India-Asia collision mountains, and consist of re-activated Paleozoic orogens. The western segment of the southern Tien Shan lies northwest of the Pamir and west of the Talas-Fergana fault. The stratigraphy, lithology, igneous and metamorphic petrology and geochemistry of this segment indicate that it was formed by the assembly of Lower Paleozoic arcs which developed into microcontinents with Upper Paleozoic mature shelf and slope clastic and carbonate sediments. Precambrian continental crust is confined to two small blocks along its southern margin. The bulk of the southern Tien Shan consists of ?Vendian to Silurian oceanic and slope clastic rocks, resting on oceanic lithosphere, and overlain by thick passive margin Devonian to mid-Carboniferous mature shelf clastics and carbonates. These are unconformably overlain by syn- and post-orogenic immature clastic sediments derived from mountains on the north formed by closure of a Carboniferus southern Tajik and a northern Vendian to Carboniferous Turkestan ocean with the southern Tien Shan microcontinent sandwiched between. Associated with these collisions are late Carboniferous to Permian intrusives, which form three south to north (though overlapping) suites; a southern calc-alkaline granodiorite-granite suite, an intermediate gabbro-monzodiorite-granite suite, and a northern alkaline monzodiorite-granite-alaskite suite. The gabbro-monzodiorite-granite suite forms the earliest subduction-related magmatism of the southern Tien Shan: rare earth element patterns are consistent with derivation from a primitive or slightly enriched mantle. The other suites show more crustal contamination. Rb and Sr vary with depth and degree of partial melting and are consistent with progressive involvement of crustal material in partial melts during collision. The gradual change in composition within each complex, lasting in some cases from 295 to 250 Ma (the entire Permian), may be explained by a consecutive shift in the melting sedimentary cover of the subducting plate from oceanic crust through transitional crust to marginal continental crust. Like the Central Asian orogenic belt (the main focus of IGCP 420), the Tien Shan represent a net addition of continental crust during the Phanerozoic. Very little of the belt has any Precambrian precursor.

Shallow seismic reflection profiles and geological structure in the Benton Hills, southeast Missouri

USGS Publications Warehouse

Palmer, J.R.; Hoffman, D.; Stephenson, W.J.; Odum, J.K.; Williams, R.A.

1997-01-01

During late May and early June of 1993, we conducted two shallow, high-resolution seismic reflection surveys (Mini-Sosie method) across the southern escarpment of the Benton Hills segment of Crowleys Ridge. The reflection profiles imaged numerous post-late Cretaceous faults and folds. We believe these faults may represent a significant earthquake source zone. The stratigraphy of the Benton Hills consists of a thin, less than about 130 m, sequence of mostly unconsolidated Cretaceous, Tertiary and Quaternary sediments which unconformably overlie a much thicker section of Paleozoic carbonate rocks. The survey did not resolve reflectors within the upper 75-100 ms of two-way travel time (about 60-100 m), which would include all of the Tertiary and Quaternary and most of the Cretaceous. However, the Paleozoic-Cretaceous unconformity (Pz) produced an excellent reflection, and, locally a shallower reflector within the Cretaceous (K) was resolved. No coherent reflections below about 200 ms of two-way travel time were identified. Numerous faults and folds, which clearly offset the Paleozoic-Cretaceous unconformity reflector, were imaged on both seismic reflection profiles. Many structures imaged by the reflection data are coincident with the surface mapped locations of faults within the Cretaceous and Tertiary succession. Two locations show important structures that are clearly complex fault zones. The English Hill fault zone, striking N30??-35??E, is present along Line 1 and is important because earlier workers indicated it has Pleistocene Loess faulted against Eocene sands. The Commerce fault zone striking N50??E, overlies a major regional basement geophysical lineament, and is present on both seismic lines at the southern margin of the escarpment. The fault zones imaged by these surveys are 30 km from the area of intense microseismicity in the New Madrid seismic zone (NMSZ). If these are northeast and north-northeast oriented fault zones like those at Thebes Gap they are favorably oriented in the modern stress field to be reactivated as right-lateral strike slip faults. Currently, earthquake hazards assessments are most dependent upon historical seismicity, and there are little geological data available to evaluate the earthquake potential of fault zones outside of the NMSZ. We anticipate that future studies will provide evidence that seismicity has migrated between fault zones well beyond the middle Mississippi Valley. The potential earthquake hazards represented by faults outside the NMSZ may be significant.

Provenance of Carboniferous sedimentary rocks in the northern margin of Dabie Mountains, central China and the tectonic significance: constraints from trace elements, mineral chemistry and SHRIMP dating of zircons

NASA Astrophysics Data System (ADS)

Li, Renwei; Li, Shuangying; Jin, Fuquan; Wan, Yusheng; Zhang, Shukun

2004-04-01

A suite of slightly metamorphosed Carboniferous sedimentary strata occurs in the northern margin of the Dabie Mountains, central China. It consists, in ascending order, of the upper Huayuanqiang Formation (C 1), the Yangshan Formation (C 1), the Daorenchong Formation (C 1-2), the most widely distributed Huyoufang Formation (C 2) and the Yangxiaozhuang Formation (C 2). The provenance of the Carboniferous sedimentary rocks is constrained by the integration of trace elements, detrital mineral chemistry and sensitive high resolution ion microprobe (SHRIMP) dating of detrital zircons, which can help to understand the connection between the provenance and the Paleozoic tectonic evolution of the Qinling-Dabie Orogen. The trace element compositions indicate that the source terrain was probably a continental island arc. Detrital tourmalines were mainly derived from aluminous and Al-poor metapelites and metapsammites, and some are sourced from Li-poor granitoids, pegmatites and aplites. Detrital garnets, found only in the uppermost Huyoufang Formation, are almandine and Mn-almandine garnets, indicating probable sources mainly from garnetiferous schists, and partly from granitoid rocks. The detrital white K-micas are muscovitic in the Huayuanqiang, Daorenchong and Huyoufang Formations, and phengitic with Si contents (p.f.u.) from 3.20 up to max. 3.47-3.53 in the uppermost Huyoufang and the Yangxiaozhuang Formations, a meta-sedimentary source. Major components in the detrital zircon age structure for the Huyoufang Formation range from 506 to 363 Ma, centering on ˜400 and ˜480 Ma, which is characteristic of the Qinling and Erlangping Groups in the Qinling and Tongbai Mountains, central China. Evidently, the major source of the Carboniferous sedimentary rocks in the northern margin of Dabie Mountains was from the southern margin of the Sino-Korean Craton represented by the Qinling and Erlangping Groups. The source area was an island-arc system during the Early Paleozoic that collided with the Sino-Korea plate towards the end of the Early Paleozoic or during the Devonian. A prominent feature in the detrital zircon age structure of the Huyoufang Formation is the Neoproterozoic detritus, which could be derived only from the Yangtze Craton. Reasonable interpretation of the two distinct source materials for the Huyoufang Formation is that the two plates were juxtaposed through collision before the late Carboniferous.

An investigation on polycyclic aromatic hydrocarbon emissions from pulverized coal combustion systems

PubMed

Pisupati; Wasco; Scaroni

2000-05-29

Results from a series of tests conducted to study the emission of polynuclear or polycyclic aromatic hydrocarbons (PAHs) from bench-scale and small industrial, water-tube boiler are discussed. A Middle Kittanning, and Upper Freeport seam coals were used in the study. Samples were extracted from the reactor outlet and from the inlet and outlet sides of the research boiler's (RB) baghouse using EPA promulgated methods.Only acenaphthene and fluoranthene were detected in down-fired combustor (DFC) samples. In addition to these two, naphthalene was detected in the RB samples. Emission factors ranged from 80 to 320 &mgr;g/kg of fuel fired. Although there were minor trends in the emissions' data, given the reproducibility limits for PAH compounds, no significant differences were found in the emissions with respect to the fuel type or form (pulverized coal (PC) vs. coal-water slurry fuel (CWSF), and raw vs. cleaned coal) and firing conditions (high and low excess air). The PAH emissions showed a decrease with increase in the firing rate.A bench-scale drop-tube reactor (DTR) was used to study the effects of temperature and residence time on PAH formation. The results revealed near constant PAH concentrations in the solid-phase samples, while the PAH concentrations in the vapor-phase samples increased as a function of temperature. At a temperature of around 1300 degrees C, the rate of PAH formation was exceeded by the rate of PAH oxidation, and PAH concentrations in the vapor phase began to decrease.

Global Diversity and Phylogeny of the Asteroidea (Echinodermata)

PubMed Central

Mah, Christopher L.; Blake, Daniel B.

2012-01-01

Members of the Asteroidea (phylum Echinodermata), popularly known as starfish or sea stars, are ecologically important and diverse members of marine ecosystems in all of the world's oceans. We present a comprehensive overview of diversity and phylogeny as they have figured into the evolution of the Asteroidea from Paleozoic to the living fauna. Living post-Paleozoic asteroids, the Neoasteroidea, are morphologically separate from those in the Paleozoic. Early Paleozoic asteroid faunas were diverse and displayed morphology that foreshadowed later living taxa. Preservation presents significant difficulties, but fossil occurrence and current accounts suggests a diverse Paleozoic fauna, which underwent extinction around the Permian-Triassic interval was followed by re-diversification of at least one surviving lineage. Ongoing phylogenetic classification debates include the status of the Paxillosida and the Concentricycloidea. Fossil and molecular evidence has been and continues to be part of the ongoing evolution of asteroid phylogenetic research. The modern lineages of asteroids include the Valvatacea, the Forcipulatacea, the Spinlosida, and the Velatida. We present an overview of diversity in these taxa, as well as brief notes on broader significance, ecology, and functional morphology of each. Although much asteroid taxonomy is stable, many new taxa remain to be discovered with many new species currently awaiting description. The Goniasteridae is currently one of the most diverse families within the Asteroidea. New data from molecular phylogenetics and the advent of global biodiversity databases, such as the World Asteroidea Database (http://www.marinespecies.org/Asteroidea/) present important new springboards for understanding the global biodiversity and evolution of asteroids. PMID:22563389

Tethys- and Atlas-related deformations in the Triassic Basin, Algeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, J.S.; Moore, S.R.; Quarles, A.I.

1995-08-01

Petroleum provinces of Algeria can be divided into Paleozoic and Mesozoic domains. Paleozoic basins are located on the Gondwanaland paleo-continent where the last significant tectonic episode is ascribed to the Late Paleozoic Hercynian Orogeny. Mesozoic basins are located on the south margin of the Neo-Tethyan seaway. These basins were subject to varying degrees of contractional deformation during the Cenozoic Atlas Orogeny. The Triassic Basin of Algeria is a Tethyan feature located above portions of the Paleozoic Oued M`ya and Ghadames Basins. Paleozoic strata are deeply truncated at the Hercynian Unconformity on a broad arch between the older basins. This ismore » interpreted to reflect rift margin rebound during Carboniferous time. Continental Lower Triassic sediments were deposited in a series of northeast trending basins which opened as the Neo-Tethys basin propagated from east to west between Africa and Europe. Middle Triassic marine transgression from the east resulted in evaporate deposition persisting through the Early Jurassic. Passive margin subsidence associated with carbonate marine deposition continued through the Early Cretaceous. Several zones of coeval wrench deformation cross the Atlas and adjoining regions. In the Triassic Basin, inversion occurred before the end of the Early Cretaceous. This episode created discrete uplifts, where major hydrocarbon accumulations have been discovered, along northeast trending lineaments. During the Eocene, the main phase of the Atlas Orogeny produced low amplitude folding of Jurassic and Cretaceous sediments. The folds detach within the Triassic-Jurassic evaporate interval. Many of these folds have been tested without success, as the deeper reservoirs do not show structural closure.« less

Underpressure in Mesozoic and Paleozoic rock units in the Midcontinent of the United States

USGS Publications Warehouse

Nelson, Philip H.; Gianoutsos, Nicholas J.; Drake, Ronald

2015-01-01

Potentiometric surfaces for Paleozoic strata, based on water well levels and selected drill-stem tests, reveal the control on hydraulic head exerted by outcrops in eastern Kansas and Oklahoma. From outcrop in the east, the westward climb of hydraulic head is much less than that of the land surface, with heads falling so far below land surface that the pressure:depth ratio in eastern Colorado is less than 5.7 kPa/m (0.25 psi/ft). Permian evaporites separate the Paleozoic hydrogeologic units from a Lower Cretaceous (Dakota Group) aquifer, and a highly saline brine plume pervading Paleozoic units in central Kansas and Oklahoma is attributed to dissolution of Permian halite. Underpressure also exists in the Lower Cretaceous hydrogeologic unit in the Denver Basin, which is hydrologically separate from the Paleozoic units. The data used to construct the seven potentiometric surfaces were also used to construct seven maps of pressure:depth ratio. These latter maps are a function of the differences among hydraulic head, land-surface elevation, and formation elevation. As a consequence, maps of pressure:depth ratio reflect the interplay of three topologies that evolved independently with time. As underpressure developed, gas migrated in response to the changing pressure regime, most notably filling the Hugoton gas field in southwestern Kansas. The timing of underpressure development was determined by the timing of outcrop exposure and tilting of the Great Plains. Explorationists in western Kansas and eastern Colorado should not be surprised if a reservoir is underpressured; rather, they should be surprised if it is not.

Geology of the Harpers Ferry Quadrangle, Virginia, Maryland, and West Virginia

USGS Publications Warehouse

Southworth, Scott; Brezinski, David K.

1996-01-01

The Harpers Ferry quadrangle covers a portion of the northeast-plunging Blue Ridge-South Mountain anticlinorium, a west-verging allochthonous fold complex of the late Paleozoic Alleghanian orogeny. The core of the anticlinorium consists of high-grade paragneisses and granitic gneisses that are related to the Grenville orogeny. These rocks are intruded by Late Proterozoic metadiabase and metarhyolite dikes and are unconformably overlain by Late Proterozoic metasedimentary rocks of the Swift Run Formation and metavolcanic rocks of the Catoctin Formation, which accumulated during continental rifting of Laurentia (native North America) that resulted in the opening of the Iapetus Ocean. Lower Cambrian metasedimentary rocks of the Loudoun, Weverton, Harpers, and Antietam Formations and carbonate rocks of the Tomstown Formation were deposited in the rift-to-drift transition as the early Paleozoic passive continental margin evolved. The Short Hill fault is an early Paleozoic normal fault that was contractionally reactivated as a thrust fault and folded in the late Paleozoic. The Keedysville detachment is a folded thrust fault at the contact of the Antietam and Tomstown Formations. Late Paleozoic shear zones and thrust faults are common. These rocks were deformed and metamorphosed to greenschist-facies during the formation of the anticlinorium. The Alleghanian deformation was accompanied by a main fold phase and a regional penetrative axial plane cleavage, which was followed by a minor fold phase with crenulation cleavage. Early Jurassic diabase dikes transected the anticlinorium during Mesozoic continental rifting that resulted in the opening of the Atlantic Ocean. Cenozoic deposits that overlie the bedrock include bedrock landslides, terraces, colluvium, and alluvium.

Remedial Investigation Report on Chestnut Ridge Operable Unit 2 (Filled Coal Ash Pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 1. Main Text

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-08-01

This document is a report on the remedial investigation (RI) of Chestnut Ridge Operable Unit (OU) 2 at the Oak Ridge Y-12 Plant. Chestnut Ridge OU 2 consists of Upper McCoy Branch (UMB), the Filled Coal Ash Pond (FCAP), and the area surrounding the Sluice Channel formerly associated with coal ash disposal in the FCAP. Chestnut Ridge OU 2 is located within the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation in Anderson County, Tennessee, approximately 24 miles west of Knoxville. The pond is an 8.5-acre area on the southern slope of Chestnut Ridge, 0.5 mile south of the mainmore » Y-12 Plant and geographically separated from the Y-12 Plant by Chestnut Ridge. The elevation of the FCAP is {approximately} 950 ft above mean sea level (msl), and it is relatively flat and largely vegetated. Two small ponds are usually present at the northeast and northwest comers of the FCAP. The Sluice Channel Area extends {approximately}1000 ft from the northern margin of the FCAP to the crest of Chestnut Ridge, which has an elevation of {approximately}1100 ft above msl. The Sluice Channel Area is largely vegetated also. McCoy Branch runs from the top of Chestnut Ridge across the FCAP into Rogers Quarry and out of the quarry where it runs a short distance into Milton Hill Lake at McCoy Embayment, termed UMB. The portion south of Rogers Quarry, within Chestnut Ridge OU 4, is termed Lower McCoy Branch. The DOE Oak Ridge Y-12 Plant disposed of coal ash from its steam plant operations as a slurry that was discharged into an ash retention impoundment; this impoundment is the FCAP. The FCAP was built in 1955 to serve as a settling basin after coal ash slurried over Chestnut Ridge from the Y-12 Plant. The FCAP was constructed by building an earthen dam across the northern tributary of McCoy Branch. The dam was designed to hold 20 years of Y-12 steam plant ash. By July 1967, ash had filled up the impoundment storage behind the dam to within 4 ft of the top.« less

Object permanence in the food-storing coal tit (Periparus ater) and the non-storing great tit (Parus major): Is the mental representation required?

PubMed

Marhounová, Lucie; Frynta, Daniel; Fuchs, Roman; Landová, Eva

2017-05-01

Object permanence is a cognitive ability that enables animals to mentally represent the continuous existence of temporarily hidden objects. Generally, it develops gradually through six qualitative stages, the evolution of which may be connected with some specific ecological and behavioral factors. In birds, the advanced object permanence skills were reported in several storing species of the Corvidae family. In order to test the association between food-storing and achieved performance within the stages, we compared food-storing coal tits (Periparus ater) and nonstoring great tits (Parus major) using an adapted version of Uzgiris & Hunt's Scale 1 tasks. The coal tits significantly outperformed the great tits in searching for completely hidden objects. Most of the great tits could not solve the task when the object disappeared completely. However, the upper limit for both species is likely to be Stage 4. The coal tits could solve problems with simply hidden objects, but they used alternative strategies rather than mental representation when searching for completely hidden objects, especially if choosing between two locations. Our results also suggest that neophobia did not affect the overall performance in the object permanence tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Geomechanical characterization of the Upper Carboniferous under thermal stress for the evaluation of a High Temperature - Mine Thermal Energy Storage (HT-MTES)

NASA Astrophysics Data System (ADS)

Hahn, Florian; Brüggemann, Nina; Bracke, Rolf; Alber, Michael

2017-04-01

The goal of this R&D project is to create a technically and economically feasible conceptual model for a High Temperature - Mine Thermal Energy Storage (HT-MTES) for the energetic reuse of a mine on the example of the Prosper-Haniel coal mine in Bottrop, Germany. This project is funded by the "Initiative Energy Storage" program of the German Federal Ministries BMWi, BMU and BMBF. At the end of 2018, the last operative coal mine in North Rhine-Westphalia, Germany (Prosper-Haniel), is going to be closed down, plugged and abandoned. Large amounts of subsurface infrastructures, resembled mainly by open parts of former galleries and mining faces are going to be flooded, after the mine is closed down and therefore have the potential to become an enormous geothermal reservoir for a seasonal heat storage. During the summer non-used (waste) heat from solar thermal power plants, garbage incineration, combined heat and power plants (CHP) or industrial production processes can be stored within dedicated drifts of the mine. During the winter season, this surplus heat can be extracted and directly utilized in commercial and/or residential areas. For the evaluation of such a HT-MTES within a former coal mine, the corresponding geomechanical parameters of the Upper Carboniferous under thermal stress needs to be evaluated. Therefore the main rock types of the Upper Carboniferous (claystone, siltstone and sandstone) are subject to a geomechanical characterization before and after thermal cyclic loadings of temperatures up to 200 °C. The samples have been collected directly from the coal mine Prosper-Haniel within a depth range of 1000 - 1200 m. Unconfined compressive and tensile strengths, as well as triaxial tests were performed at room temperature. Furthermore, a range of petrophysical properties like density, thin-section analysis and P-wave velocities were determined. First results show an indication that the overall strength properties of the samples are not effected by thermal cyclic loadings with temperatures of up to 200 °C. However, a reduction in the Young's modulus was observed in all samples, after thermal cyclic loads were induced. This effect is mainly correlated to a relaxation of the grain bonds and a pore space expansion. Currently, the experimental focus was set on the evaluation of the collected siltstone samples. Therefore further experiments are needed to undermine these results also for the claystone and sandstone samples.

Tectonic transition associated with Kazakhstan Orocline in the Late Paleozoic: magmatic archives of western Chinese Tianshan

NASA Astrophysics Data System (ADS)

Cai, Keda

2016-04-01

Kazakhstan accretionary system was a principle component of the Central Asian Orogenic Belt (CAOB) that is one of the largest accretionary orogens on earth. The Kazakhstan composite continent could have been established in the Early Paleozoic by the Kazakhstan accretionary system in the form of progressively amalgamations of diverse tectonic units, such as continental ribbon, accretionary prim, oceanic remnant and arc material. Subsequently, the composite continent was bended to form a spectacular U-shaped architecture that probably occurred in the Late Paleozoic. The western Chinese Tianshan is situated on the south wing of the Kazakhstan Orocline, featured by extensive magmatim, intense deformation and voluminous mineralization. Our new geochronological and geochemical data suggest a noticeable magmatic gap between Late Devonian and Early carboniferous and contrasting magma sources of these magmatic rocks. The significant shifts correspond to the tectonic transition from terrane amalgamation to mountain bending in the Early Paleozoic. This study was financially supported by the Major Basic Research Project of the Ministry of Science and Technology of China (2014CB448000), Xinjiang outstanding youth scientific grant (2013711003) and the Talent Awards to KDC from the China Government under the 1000 Talent Plan.

Merging seismic and MT in Garden Valley, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Telleen, K.E.

1986-04-01

In the northern part of Garden Valley, Nevada, a 1978 regional seismic program encountered a large area of poor to no-reflection data. Surface geology suggested that a large high structure might underlie the valley floor, and that shallowly buried basalts were causing the poor data. The implied strongly layered structure of electrical resistivity - resistive basalt on conductive Tertiary clastics on resistive paleozoic carbonates - formed an ideal theater for the magnetotelluric method. In 1984, Conoco acquired 48 magnetotelluric sites on about a half-mile grid. These data supported the presence of a buried high block in the Paleozoic rocks andmore » allowed confident mapping of its outlines. In addition, the magnetotelluric survey showed a thin, shallowly buried resistor coextensive with the seismic no-reflection area. In 1985, a high-effort repeat of the earlier no-reflection seismic line confirmed the high block, improved the fault interpretation, and provided weak guidance on the depth of the targeted Paleozoic rocks. Because Garden Valley's Paleozoic stratigraphy differs negligibly from that at nearby Grant Canyon field, the high block constitutes an attractive prospect - possibly the first one found in Nevada due largely to magnetotelluric surveying.« less

Abnormal high surface heat flow caused by the Emeishan mantle plume

NASA Astrophysics Data System (ADS)

Jiang, Qiang; Qiu, Nansheng; Zhu, Chuanqing

2016-04-01

It is commonly believed that increase of heat flow caused by a mantle plume is small and transient. Seafloor heat flow data near the Hawaiian hotspot and the Iceland are comparable to that for oceanic lithosphere elsewhere. Numerical modeling of the thermal effect of the Parana large igneous province shows that the added heat flow at the surface caused by the magmatic underplating is less than 5mW/m2. However, the thermal effect of Emeishan mantle plume (EMP) may cause the surface hear-flow abnormally high. The Middle-Late Emeishan mantle plume is located in the western Yangtze Craton. The Sichuan basin, to the northeast of the EMP, is a superimposed basin composed of Paleozoic marine carbonate rocks and Mesozoic-Cenozoic terrestrial clastic rocks. The vitrinite reflectance (Ro) data as a paleogeothermal indicator records an apparent change of thermal regime of the Sichuan basin. The Ro profiles from boreholes and outcrops which are close to the center of the basalt province exhibit a 'dog-leg' style at the unconformity between the Middle and Upper Permian, and they show significantly higher gradients in the lower subsection (pre-Middle Permian) than the Upper subsection (Upper Permian to Mesozoic). Thermal history inversion based on these Ro data shows that the lower subsection experienced a heat flow peak much higher than that of the upper subsection. The abnormal heat flow in the Sichuan basin is consistent with the EMP in temporal and spatial distribution. The high-temperature magmas from deep mantle brought heat to the base of the lithosphere, and then large amount of heat was conducted upwards, resulting in the abnormal high surface heat flow.

Shorter contributions to general geology, 1917

USGS Publications Warehouse

White, David

1918-01-01

A. Baked shale and slag formed by the burning of coal beds / G.S. Rogers B. The Newington moraine, Maine, New Hampshire, and Massachusetts / F.J. Katz and Arthur Keith C.A comparison of Paleozoic sections in southern New Mexico / N.H. Darton D. Wasatch fossils in so-called Fort Union beds of the Powder River Basin, Wyo., and their bearing on the stratigraphy of the region / C.H. Wegemann E. Geologic history indicated by the fossiliferous deposits of the Wilcox group at Meridian, Miss. / E.W. Berry F.A fossil flora from the Frontier formation of southwestern Wyoming / F.H. Knowlton G. The stratigraphic position and faunal associates of the orbitoid Foraminifera of the genus Orthophragmina from Georgia and Florida / C.W. Cooke G. Orbitoid Foraminifera of the genus Orthophragmina from Georgia and Florida / J.A. Cushman H. The Pliocene history of northern and central Mississippi / E.W. Shaw I. Stratigraphy in northwestern Maine and southeastern New Hampshire / F.J. Katz J. The Flaxville gravel and its relation to other terrace gravels of the northern Great Plains / A.J. Collier K. The Helderberg limestone of central Pennsylvania / J.B. Reeside L. Stratigraphy of the Hanna Basin, Wyo. / C.F. Bowen

Dissolved organic matter removal during coal slag additive soil aquifer treatment for secondary effluent recharging: Contribution of aerobic biodegradation.

PubMed

Wei, Liangliang; Li, Siliang; Noguera, Daniel R; Qin, Kena; Jiang, Junqiu; Zhao, Qingliang; Kong, Xiangjuan; Cui, Fuyi

2015-06-01

Recycling wastewater treatment plant (WWTP) effluent at low cost via the soil aquifer treatment (SAT), which has been considered as a renewable approach in regenerating potable and non-potable water, is welcome in arid and semi-arid regions throughout the world. In this study, the effect of a coal slag additive on the bulk removal of the dissolved organic matter (DOM) in WWTP effluent during SAT operation was explored via the matrix configurations of both coal slag layer and natural soil layer. Azide inhibition and XAD-resins fractionation experiments indicated that the appropriate configuration designing of an upper soil layer (25 cm) and a mixture of soil/coal slag underneath would enhance the removal efficiency of adsorption and anaerobic biodegradation to the same level as that of aerobic biodegradation (31.7% vs 32.2%), while it was only 29.4% compared with the aerobic biodegradation during traditional 50 cm soil column operation. The added coal slag would preferentially adsorb the hydrophobic DOM, and those adsorbed organics could be partially biodegraded by the biomass within the SAT systems. Compared with the relatively lower dissolved organic carbon (DOC), ultraviolet light adsorption at 254 nm (UV-254) and trihalomethane formation potential (THMFP) removal rate of the original soil column (42.0%, 32.9%, and 28.0%, respectively), SSL2 and SSL4 columns would enhance the bulk removal efficiency to more than 60%. Moreover, a coal slag additive in the SAT columns could decline the aromatic components (fulvic-like organics and tryptophan-like proteins) significantly. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evidence for hot Mississippi Valley-type brines in the Reelfoot Rift complex, south-central United States, in Late Pennsylvanian-Early Permian

USGS Publications Warehouse

Leach, D.L.; Apodaca, L.E.; Repetski, J.E.; Powell, J.W.; Rowan, E.L.

1997-01-01

Petrographic and fluid inclusion studies of sparry dolomite cement from Upper Cambrian to Lower Ordovician rocks and conodont thermal-alteration indices provide evidence that hot mississippi valley-type brines were once present in the Reelfoot Rift complex. The cathodoluminescent microstratigraphy of sparry dolomite cement in the Reelfoot Rift resembles that of sparry dolomite cement associated with widespread mississippi valley-type deposition in the Ozark region. If correlative cathodoluminescent zones in the sparry dolomite from the Ozark and Reelfoot Rift regions indicate broadly contemporaneous dolomite deposition, then the results show that the Ozark MVT-type hydrothermal system extended into the Reelfoot region and onto the western flank of the Nashville Dome. Independent evidence supports migration of MVT-type brines into the Ozark region from the Reelfoot Rift complex in late Paleozoic time.

The hydrogeologic framework for the southeastern Coastal Plain aquifer system of the United States

USGS Publications Warehouse

Renken, R.A.

1984-01-01

Tertiary and Cretaceous age sand aquifers of the southeastern United States Coastal Plain constitute a distinct multistate hydrogeologic regime informally defined as the southeastern sand aquifer. Seven regional hydrogeologic units are defined; four regional aquifer units and three regional confining beds. Sand aquifers of this system consist of quartzose, feldspathic, and coarse to fine sand and sandstone and minor limestone; confining beds are composed of clay, shale, chalk, and marl. Three hydrogeologic units of Cretaceous to Holocene age overlie the sand system: the surficial aquifer, upper confining unit, and Floridan aquifer system. These three units are not part of the southeastern sand aquifer, but are an integral element of the total hydrogeologic system, and some act as a source of recharge to, or discharge from the underlying clastic sediments. Low-permeability strata of Paleozoic to early Mesozoic age form the base off the total system. (USGS)

New monoaromatic steroids in organic matter of the apocatagenesis zone

NASA Astrophysics Data System (ADS)

Kashirtsev, V. A.; Fomin, A. N.; Shevchenko, N. P.; Dolzhenko, K. V.

2016-08-01

According to the materials of geochemical study in the core of the ultradeep hole SV-27 of aromatic fractions of bitumoids of the Vilyui syneclise (East Siberia) by the method of chromatography-mass spectrometry, starting from the depth of >5000 m, four diastereomers of previously unknown hydrocarbons, which become predominant in the fraction at a depth of ˜6500 m, were distinguished. Similar hydrocarbons were found in organic matter of Upper Paleozoic rocks of the Kharaulakh anticlinorium in the Verkhoyansk folded area. According to the intense molecular ion m/z 366 and the character of the basic fragmental ions (m/z 238, 309, and 323), the major structure of the compounds studied was determined as 17-desmethyl-23-methylmonoaromatic steroid C27. The absence of such steroids in oil of the Vilyui syneclise shows that deep micro-oils did not participate in the formation of oil fringes of gas condensate deposits of the region.

Fault and joint geometry at Raft River Geothermal Area, Idaho

NASA Astrophysics Data System (ADS)

Guth, L. R.; Bruhn, R. L.; Beck, S. L.

1981-07-01

Raft River geothermal reservoir is formed by fractures in sedimentary strata of the Miocene and Pliocene salt lake formation. The fracturing is most intense at the base of the salt lake formation, along a decollement that dips eastward at less than 50 on top of metamorphosed precambrian and lower paleozoic rocks. Core taken from less than 200 m above the decollement contains two sets of normal faults. The major set of faults dips between 500 and 700. These faults occur as conjugate pairs that are bisected by vertical extension fractures. The second set of faults dips 100 to 200 and may parallel part of the basal decollement or reflect the presence of listric normal faults in the upper plate. Surface joints form two suborthogonal sets that dip vertically. East-northeast-striking joints are most frequent on the limbs of the Jim Sage anticline, a large fold that is associated with the geothermal field.

Precambrian Continent Arctida: A New Kinematic Reconstruction of Late Precambrian - Early Paleozoic Arctida U Europe (baltia) Collision

NASA Astrophysics Data System (ADS)

Borisova, T. P.; Guertseva, M. V.; Egorov, A. Ju.; Kononov, M. V.; Kouznetsov, N. B.

In according to L.P.Zonenshain and L.M.Natapov (1988, 1990), different size conti- nental blocks locating at the margins and inside of present-day Arctic ocean composed the hypothetical early Paleozoic paleocontinent Arctida. The blocks are Kara block (north part of Taymir peninsula, Severnaja Zemlja archipelago and Franz Joseph Land archipelago), north part of Alaska (northward Bruks ridge), Chukchi block, Novosi- birsky block (Novosibirskiye islands together their shelves), several fragments north- ward to the Innuitian orogen (north parts of Peary Land and Ellesmere Island), and Lomonosov ridgeSs block. In the previous kinematic reconstruction it was believed that Arctida as a whole collided with north flanks of Laurentia (Innuitian margin) and Europe (Baltia, Barentsia margin) in middle Paleozoic time. Later, the Arctida (been a fragment of supercontinent Pangea) was fragmented due to a spreading in the Arctic ocean and north part of Atlantic ocean in late Mesozoic and Cenozoic times. Then ArctidaSs fragments were accreted to the Eurasia and North America conti- nents. During the last decade "AEROGEOLOGIA" company has been gathered new data (geologic, stratigraphical, paleomagnetic, and others) of Russian Arctic sector and Svalbard. The data were summarized into "Paleogeographical Atlas for the Rus- sian Arctic sector and Svalbard from Vendian to Jurassic times" (see Abstact SE1.04, ID-NR: EGS02-A-02453). An analyzing of the maps for Vend and Cambrian times allows us to reconsider a few stages of kinematic scenario of late Precambrian - early Paleozoic Arctida U Europe collision. 1) Old interpretation: Arctida was considered as an isolated paleocontinent during early Paleozoic time. New interpretation: during the early Paleozoic Arctida together Europe (Baltia) were assembled into a paleo- continent named us Arcteurope. This conclusion is based on excellent coincidence of Paleozoic paleomagnetic poles of the Kara block (which is a part of Arctida) and Europe (Baltia). 2) Old interpretation: the dextral Kara-Barents shear zone was con- sidered as Europe (Baltia) U Arctida late Devonian suture zone. New interpretation: A collision of Europe (Baltia) and Arctida occurred about the time boundary between Vend and Cambrian times on the Timan suture zone. Time of the collision marked 1 by the Cambrian granitoids of the Timan ridge and west slope of North Urals. 3). Old interpretation: During late Precambrian times Barentsia sialic block was believed as an isolated microcontinent, been accreted to the Europe (Baltia) in the latest Ven- dian time. New interpretation: Barentsia sialic block was a part of Arctida during late Precambrian time. 2

Integration of vertical and in-seam horizontal well production analyses with stochastic geostatistical algorithms to estimate pre-mining methane drainage efficiency from coal seams: Blue Creek seam, Alabama

PubMed Central

Karacan, C. Özgen

2015-01-01

Coal seam degasification and its efficiency are directly related to the safety of coal mining. Degasification activities in the Black Warrior basin started in the early 1980s by using vertical boreholes. Although the Blue Creek seam, which is part of the Mary Lee coal group, has been the main seam of interest for coal mining, vertical wellbores have also been completed in the Pratt, Mary Lee, and Black Creek coal groups of the Upper Pottsville formation to degasify multiple seams. Currently, the Blue Creek seam is further degasified 2–3 years in advance of mining using in-seam horizontal boreholes to ensure safe mining. The studied location in this work is located between Tuscaloosa and Jefferson counties in Alabama and was degasified using 81 vertical boreholes, some of which are still active. When the current long mine expanded its operation into this area in 2009, horizontal boreholes were also drilled in advance of mining for further degasification of only the Blue Creek seam to ensure a safe and a productive operation. This paper presents an integrated study and a methodology to combine history matching results from vertical boreholes with production modeling of horizontal boreholes using geostatistical simulation to evaluate spatial effectiveness of in-seam boreholes in reducing gas-in-place (GIP). Results in this study showed that in-seam wells' boreholes had an estimated effective drainage area of 2050 acres with cumulative production of 604 MMscf methane during ~2 years of operation. With horizontal borehole production, GIP in the Blue Creek seam decreased from an average of 1.52 MMscf to 1.23 MMscf per acre. It was also shown that effective gas flow capacity, which was independently modeled using vertical borehole data, affected horizontal borehole production. GIP and effective gas flow capacity of coal seam gas were also used to predict remaining gas potential for the Blue Creek seam. PMID:26435557

Integration of vertical and in-seam horizontal well production analyses with stochastic geostatistical algorithms to estimate pre-mining methane drainage efficiency from coal seams: Blue Creek seam, Alabama.

PubMed

Karacan, C Özgen

2013-07-30

Coal seam degasification and its efficiency are directly related to the safety of coal mining. Degasification activities in the Black Warrior basin started in the early 1980s by using vertical boreholes. Although the Blue Creek seam, which is part of the Mary Lee coal group, has been the main seam of interest for coal mining, vertical wellbores have also been completed in the Pratt, Mary Lee, and Black Creek coal groups of the Upper Pottsville formation to degasify multiple seams. Currently, the Blue Creek seam is further degasified 2-3 years in advance of mining using in-seam horizontal boreholes to ensure safe mining. The studied location in this work is located between Tuscaloosa and Jefferson counties in Alabama and was degasified using 81 vertical boreholes, some of which are still active. When the current long mine expanded its operation into this area in 2009, horizontal boreholes were also drilled in advance of mining for further degasification of only the Blue Creek seam to ensure a safe and a productive operation. This paper presents an integrated study and a methodology to combine history matching results from vertical boreholes with production modeling of horizontal boreholes using geostatistical simulation to evaluate spatial effectiveness of in-seam boreholes in reducing gas-in-place (GIP). Results in this study showed that in-seam wells' boreholes had an estimated effective drainage area of 2050 acres with cumulative production of 604 MMscf methane during ~2 years of operation. With horizontal borehole production, GIP in the Blue Creek seam decreased from an average of 1.52 MMscf to 1.23 MMscf per acre. It was also shown that effective gas flow capacity, which was independently modeled using vertical borehole data, affected horizontal borehole production. GIP and effective gas flow capacity of coal seam gas were also used to predict remaining gas potential for the Blue Creek seam.

Results of exploration at the Old Leyden coal mine, Jefferson County, Colorado

USGS Publications Warehouse

Gude, A.J.; McKeown, F.A.

1953-01-01

Six diamond core holes totaling 2, 201 feet were drilled by the. U, S. Bureau of Mines under contract to the U. S. Atomic Energy Commission at the Old Leyden coal mine, Jefferson County, Colo. The holes were spotted on the basis of geologic mapping by the U. S. Geological survey and were drilled to explore the lateral and downward extent of a uranium-bearing coal and the associated carnotite deposits in the adjacent sandstone° The data obtained from the diamond-core holes helped to explain the geology and structural control of the deposit. The uranium is most abundant in a coal bed that in places has been brecciated by shearing. and then altered to a hard, dense, and silicified rock. The uraniferous coal is in the nearly vertical beds of the Laramie formation of Upper Cretaceous age. Small lenticular bodies of uraniferous material, 50 feet long, 25 to 30 feet wide, and 2 to 4 feet thick, occur at intervals in the coal and silicified coal over a strike length of about 800 feet. These bodies contain 0.10 to 0.50 percent uranium. Data obtained from the drilling indicate a discontinuous radioactive zone between these higher-grade bodies; assays of samples from the cores range from 0.001 to 0.10 percent uranium. All drill holes were probed by Survey and A. E. C. logging equipment and showed anomalies where the core assayed more than 0.005 percent uranium. Material of ore grade--0.10 percent uranium--was found in one core; the rock in the other five holes was of lower grade. The presence of the radioactive zone in all holes suggests, however, that uranium is distributed irregularly in a southerly plunging deposit which is exposed in the adit, on the outcrop, and in other diamond-drill holes that were put down by the lessee.

Multidisciplinary Geophysical Study of the Earth’s Upper Structure.

DTIC Science & Technology

1988-12-27

structures normally detected by geophysical methods. This study was unique in several respects and it offers some original approaches to...that the Avalonian Superterrane within the region of the present study, at least, originally consisted, in part, of carbonate and quartzite...time. Thus large parts of the Avalonian composite tcrranc, especially the Esmond -Dedham Tcrrane that contains Pennsylvanian coal basins, may be

27. VIEW OF SOUTHERN PORTION OF EAST BOILER ROOM LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. VIEW OF SOUTHERN PORTION OF EAST BOILER ROOM LOOKING EAST AT UPPER PORTION BOILER 904. BOILER 904 WAS MANUFACTURED BY RILEY STOKER AND INSTALLED IN 1944. ORIGINALLY FUELED BY PULVERIZED COAL, IT WAS CONVERTED TO GAS/OIL OPERATION IN 1978 AND OPERATED UNTIL THE PLANT CLOSED. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

Organic petrology of Paleocene Marcelina Formation coals, Paso Diablo mine, western Venezuela: Tectonic controls on coal type

USGS Publications Warehouse

Hackley, P.C.; Martinez, M.

2007-01-01

About 7??Mt of high volatile bituminous coal are produced annually from the four coal zones of the Upper Paleocene Marcelina Formation at the Paso Diablo open-pit mine of western Venezuela. As part of an ongoing coal quality study, we have characterized twenty-two coal channel samples from the mine using organic petrology techniques. Samples also were analyzed for proximate-ultimate parameters, forms of sulfur, free swelling index, ash fusion temperatures, and calorific value. Six of the samples represent incremental benches across the 12-13??m thick No. 4 bed, the stratigraphically lowest mined coal, which is also mined at the 10??km distant Mina Norte open-pit. Organic content of the No. 4 bed indicates an upward increase of woody vegetation and/or greater preservation of organic material throughout the life of the original mire(s). An upward increase in telovitrinite and corresponding decrease in detrovitrinite and inertinite illustrate this trend. In contrast, stratigraphically higher coal groups generally exhibit a 'dulling upward' trend. The generally high inertinite content, and low ash yield and sulfur content, suggest that the Paso Diablo coals were deposited in rain-fed raised mires, protected from clastic input and subjected to frequent oxidation and/or moisture stress. However, the two thinnest coal beds (both 0.7??m thick) are each characterized by lower inertinite and higher telovitrinite content relative to the rest of Paso Diablo coal beds, indicative of less well-established raised mire environments prior to drowning. Foreland basin Paleocene coals of western Venezuela, including the Paso Diablo deposit and time-correlative coal deposits of the Ta??chira and Me??rida Andes, are characterized by high inertinite and consistently lower ash and sulfur relative to Eocene and younger coals of the area. We interpret these age-delimited coal quality characteristics to be due to water availability as a function of the tectonic control of subsidence rate. It is postulated that slower subsidence rates dominated during the Paleocene while greater foreland basin subsidence rates during the Eocene-Miocene resulted from the loading of nappe thrust sheets as part of the main construction phases of the Andean orogen. South-southeastward advance and emplacement of the Lara nappes during the oblique transpressive collision of the Caribbean and South American tectonic plates in the Paleocene was further removed from the sites of peat deposition, resulting in slower subsidence rates. Slower subsidence in the Paleocene may have favored the growth of raised mires, generating higher inertinite concentrations through more frequent moisture stress. Consistently low ash yield and sulfur content would be due to the protection from clastic input in raised mires, in addition to the leaching of mineral matter by rainfall and the development of acidic conditions preventing fixation of sulfur. In contrast, peat mires of Eocene-Miocene age encountered rapid subsidence due to the proximity of nappe emplacement, resulting in lower inertinite content, higher and more variable sulfur content, and higher ash yield.

Seismic Azimuthal Anisotropy of the Lower Paleozoic Shales in Northern Poland: can we reliably detect it?

NASA Astrophysics Data System (ADS)

Cyz, Marta; Malinowski, Michał

2017-04-01

Analysis of the azimuthal anisotropy is an important aspect of characterization the Lower Paleozoic shale play in northern Poland, since it can be used to map pre-existing fracture networks or help in optimal placement of the horizontal wells. Previous studies employed Velocity versus Azimuth (VVAz) method and found that this anisotropy is weak - on the order of 1-2%, only locally - close to major fault zones - being higher (ca. 7%). This is consistent with the recent re-interpretation of the cross-dipole sonic data, which indicates average shear wave anisotropy of 1%. The problem with the VVAz method is that it requires good definition of the interval, for which the analysis is made and it should be minimum 100 ms thick. In our case, the target intervals are thin - upper reservoir (Lower Silurian Jantar formation) is 15 m thick, lower reservoir (Upper Ordovician Sasino formation) is 25 m thick. Therefore, we prefer to use the Amplitude vs Azimuth (AVAz) method, which can be applied on a single horizon (e.g. the base of the reservoir). However, the AVAz method depends critically on the quality of the seismic data and preservation of amplitudes during processing. On top of the above mentioned issues, physical properties of the Lower Paleozoic shales from Poland seem to be unfavourable for detecting azimuthal anisotropy. For example, for both target formations, parameter g=(Vs/Vp)2 is close to 0.32, which implies that the anisotropy expressed by the anisotropic gradient in the dry (i.e. gas-filled fractures) case is close to zero. In case of e.g. the Bakken Shale, g is much higher (0.38-0.4), leading to a detectable anisotropic signature even in the dry case. Modelling of the synthetic AVAz response performed using available well data suggested that anisotropic gradient in the wet (fluid-filled) case should be detectable even in case of the weak anisotropy (1-2%). This scenario is consistent with the observation, that the studied area is located in the liquid/condensate window. Promising results of the synthetic modelling allowed us to perform analysis on the real data: a subset (52.8 km2) of a large modern wide-azimuth 3D seismic survey from northern Poland. The seismic data were pre-stack depth migrated using full-azimuth non-sectored type migration algorithm, providing excellent input for AVAz. We perform both the classical Ruger and Fourier Coefficients AVAz. Results of the AVAz analysis of the real data correlate to some extent with the earlier VVAz results, both in terms of the anisotropy magnitude and orientation. Despite the weak anisotropy, obtained orientations are more or less consistent with the available image (XRMI) logs from the vertical wells. This work has been funded by the Polish National Centre for Research and Development within the Blue Gas project (No BG2/SHALEMECH/14). Data were provided by the PGNiG SA. We thank CGG GeoSoftware for the donation of the Hampson-Russell ProAZ software.

Secretinite-Reflectance and chemical data from two high volatile bituminous coals (Upper Carboniferous) of North America

USGS Publications Warehouse

Lyons, P.C.; Mastalerz, Maria

2001-01-01

Secretinite - a maceral of the inertinite group as recognized by the ICCP in 1996- is a noncellular maceral of seed fern origin. New reflectance data indicate that this maceral has primary anisotropy with bireflectances of 0.4% to 0.9% in high-volatile B bituminous (Ro = 0.6%) Carboniferous coal of North America. The highest reflectance is in cross-section as opposed to longitudinal section. Characteristic feature of secretinite is the virtual absence of Si and Al, unlike that in associated vitrinite. This indicates the absence of submicron aluminosilicates in secretinite and their presence in vitrinites. Secretinite is highly aromatic as indicated by low O/C ratios and high contribution of aromatic hydrogen bands detected by FTIR analysis. ?? 2001 Elsevier Science B.V. All rights reserved.

Chronology of paleozoic metamorphism and deformation in the Blue Ridge thrust complex, North Carolina and Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldberg, S.A.; Dallmeyer, R.D.

1997-05-01

The Blue Ridge province in northwestern North Carolina and northeastern Tennessee records a multiphase collisional and accretionary history from the Mesoproterozoic through the Paleozoic. To constrain the tectonothermal evolution in this region, radiometric ages have been determined for 23 regionally metamorphosed amphibolites, granitic gneisses, and pelitic schists and from mylonites along shear zones that bound thrust sheets and within an internal shear zone. The garnet ages from the Pumpkin Patch a thrust sheet (458, 455, and 451 Ma) are similar to those from the structurally overlying Spruce Pine thrust sheet (460, 456, 455, and 450 Ma). Both thrust sheets exhibitmore » similar upper amphibolite-facies conditions. Because of the high closure temperature for garnet, the garnet ages are interpreted to date growth at or near the peak of Taconic metamorphism. Devonian metamorphic ages are recognized in the Spruce Pine thrust sheet, where Sm-Nd and Rb-Sr garnet ages of 386 and 393 Ma and mineral isochron ages of 397 {+-} 14 and 375 {+-} 27 Ma are preserved. Hornblendes record similar {sup 40}Ar/{sup 39}Ar, Sm-Nd, and Rb-Sr ages of 398 to 379 Ma. Devonian {sup 40}Ar/{sup 39}Ar hornblende ages are also recorded in the structurally lower Pumpkin Patch thrust sheet. The Devonian mineral ages are interpreted to date a discrete tectonothermal event, as opposed to uplift and slow cooling from an Ordovician metamorphic event. The Mississippian mylonitization is interpreted to represent thrusting and initial assembly of crystalline sheets associated with the Alleghanian orogeny. The composite thrust stack of the Blue Ridge complex was subsequently thrust northwestward along the Linville Falls fault during middle Alleghanian orogeny (about 300 Ma).« less

Late Paleozoic tectonics of the Solonker Zone in the Wuliji area, Inner Mongolia, China: Insights from stratigraphic sequence, chronology, and sandstone geochemistry

NASA Astrophysics Data System (ADS)

Shi, Guanzhong; Song, Guangzeng; Wang, Hua; Huang, Chuanyan; Zhang, Lidong; Tang, Jianrong

2016-09-01

The geology in the Wuliji area (including the Enger Us and Quagan Qulu areas) is important for understanding the Late Paleozoic tectonics of the Solonker Zone. Ultramafic/mafic rocks in the Enger Us area, previously interpreted as an ophiolitic suture, are actually lava flows and sills in a Permian turbiditic sequence and a small body of fault breccia containing serpentinite. Subduction zone features, such as accretionary complexes, magmatic arc volcanics or LP/HP metamorphism are absent. Early Permian N-MORB mafic rocks and Late Permian radiolarian cherts accompanied by turbidites and tuffeous rocks indicate a deep water setting. In the Quagan Qulu area, outcrops of the Late Carboniferous to Permian Amushan Formation are composed of volcano-sedimenary rocks and guyot-like reef limestone along with a Late Permian volcano-sedimentary unit. A dacite lava in the Late Permian volcano-sedimentary unit yields a zircon U-Pb age of 254 Ma. The gabbros in the Quagan Qulu area are intruded into the Amushan Formation and caused contact metamorphism of country rocks. Sandstones in the Upper Member of the Amushan Formation contain detrital clasts of volcanic fragments and mineral clasts of crystalline basement rocks (i.e. biotite, muscovite and garnet). Geochemical analysis of volcaniclastic sandstones shows a magmatic affinity to both continental island arc (CIA) and active continental margin (ACM) tectonic settings. A Late Permian incipient rift setting is suggested by analyzing the lithostratigraphic sequence and related magmatism in the Wuliji area. The volcano-sedimentary rocks in the Wuliji area experienced a nearly N-S shortening that was probably related to the Early Mesozoic nearly N-S compression well developed in other areas close to the Wuliji area.

Birth, life, and demise of the Andean-syn-collisional Gissar arc: Late Paleozoic tectono-magmatic-metamorphic evolution of the southwestern Tian Shan, Tajikistan

NASA Astrophysics Data System (ADS)

Worthington, James R.; Kapp, Paul; Minaev, Vladislav; Chapman, James B.; Mazdab, Frank K.; Ducea, Mihai N.; Oimahmadov, Ilhomjon; Gadoev, Mustafo

2017-10-01

The amalgamation of the Central Asian Orogenic Belt in the southwestern Tian Shan in Tajikistan is represented by tectono-magmatic-metamorphic processes that accompanied late Paleozoic ocean closure and collision between the Karakum-Tarim and Kazakh-Kyrgyz terranes. Integrated U-Pb geochronology, thermobarometry, pseudosection modeling, and Hf geochemistry constrain the timing and petro-tectonic nature of these processes. The Gissar batholith and the Garm massif represent an eastward, along-strike increase in paleodepth from upper-batholith ( 21-7 km) to arc-root ( 36-19 km) levels of the Andean-syn-collisional Gissar arc, which developed from 323-288 Ma in two stages: (i) Andean, I-type granitoid magmatism from 323-306 Ma due to northward subduction of the Gissar back-arc ocean basin under the Gissar microcontinent, which was immediately followed by (ii) syn-collisional, I-S-type granitoid magmatism in the Gissar batholith and the Garm massif from 304-288 Ma due to northward subduction/underthrusting of Karakum marginal-continental crust under the Gissar microcontinent. A rapid isotopic pull-up from 288-286 Ma signals the onset of juvenile, alkaline-syenitic, post-collisional magmatism by 280 Ma, which was driven by delamination of the Gissar arclogite root and consequent convective asthenospheric upwelling. Whereas M-HT/LP prograde metamorphism in the Garm massif (650-750°C/6-7 kbar) from 310-288 Ma was associated with subduction-magma inundation and crustal thickening, HT/LP heating and decompression to peak-metamorphic temperatures ( 800-820°C/6-4 kbar) at 288 ± 6 Ma was driven by the transmission of a post-collisional, mantle-derived heat wave through the Garm-massif crust.

Bedrock geologic map of the northern Alaska Peninsula area, southwestern Alaska

USGS Publications Warehouse

Wilson, Frederic H.; Blodgett, Robert B.; Blome, Charles D.; Mohadjer, Solmaz; Preller, Cindi C.; Klimasauskas, Edward P.; Gamble, Bruce M.; Coonrad, Warren L.

2017-03-03

The northern Alaska Peninsula is a region of transition from the classic magmatic arc geology of the Alaska Peninsula to a Proterozoic and early Paleozoic carbonate platform and then to the poorly understood, tectonically complex sedimentary basins of southwestern Alaska. Physiographically, the region ranges from the high glaciated mountains of the Alaska-Aleutian Range to the coastal lowlands of Cook Inlet on the east and Bristol Bay on the southwest. The lower Ahklun Mountains and finger lakes on the west side of the map area show strong effects from glaciation. Structurally, a number of major faults cut the map area. Most important of these are the Bruin Bay Fault that parallels the coast of Cook Inlet, the Lake Clark Fault that cuts diagonally northeast to southwest across the eastern part of the map area, and the presently active Holitna Fault to the northwest that cuts surficial deposits.Distinctive rock packages assigned to three provinces are overlain by younger sedimentary rocks and intruded by widely dispersed latest Cretaceous and (or) early Tertiary granitic rocks. Much of the east half of the map area lies in the Alaska-Aleutian Range province; the Jurassic to Tertiary Alaska-Aleutian Range batholith and derivative Jurassic sedimentary rocks form the core of this province, which is intruded and overlain by the Aleutian magmatic arc. The Lime Hills province, the carbonate platform, occurs in the north-central part of the map area. The Paleozoic and Mesozoic Ahklun Mountains province in the western part of the map area includes abundant chert, argillite, and graywacke and lesser limestone, basalt, and tectonic mélange. The Kuskokwim Group, an Upper Cretaceous turbidite sequence, is extensively exposed and bounds all three provinces in the west-central part of the map area.

Correlation between high-resolution remote-sensing imagery and detailed field mapping in Cordilleran Miogeocline

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feldman, S.C.; Taranik, J.V.

1986-05-01

Selected areas were mapped at a scale of 1:6000 in the southern hot Creek Range (south-central Nevada), which is underlain by Paleozoic autochthonous limestone, shale, and sandstone, Paleozoic allochthonous chert and siltstone, and Tertiary rhyolitic to dactitic ash flow tuff. The mapping was compared with computer-processed Airborne Imaging Spectrometer (AIS) data and Landsat Thematic Mapper (TM) imagery. The AIS imagery of the Hot Creek Range was acquired in 1984 by a NASA C-130 aircraft; it has a spatial resolution of 12 m, and swath width of 380 m. The sensor was developed by the Jet Propulsion Laboratory and is themore » first in a series of NASA imaging spectrometers. The AIS collects 128 spectral bands, having a bandwidth of approximately 9 nm, in the short-wave infrared between 1.2 and 2.4 ..mu..m. This part of the spectrum contains important narrow spectral absorption features for the carbonate ion, hydroxyl ion, and water of hydration. Using computer-processed AIS imagery, therefore, the authors can separate calcite from dolomite, and kaolinite from illite and montmorillonite as well as differentiate geologic units containing these minerals. On the AIS imagery, the Upper Mississippian Tripon Pass Limestone shows a distinctive calcite absorption feature at 2.34 ..mu..m; this feature is not as pronounced in Cambrian and Ordovician limestones. The dolomitized Nevada Formation exhibits the dolomite absorption feature at 2.32 ..mu..m. Clay mineral absorption features near 2.2 ..mu..m can be distinguished in altered volcanics. Mineralogic identification was confirmed with field and laboratory spectroradiometer measurements, thin-section examination, and x-ray analysis. AIS results and field mapping were also compared to computer-processed Landsat TM imagery, the highest spectral and spatial resolution worldwide data set currently available.« less

Late Jurassic - Early Cretaceous convergent margins of Northeastern Asia with Northwestern Pacific and Proto-Arctic oceans

NASA Astrophysics Data System (ADS)

Sokolov, Sergey; Luchitskaya, Marina; Tuchkova, Marianna; Moiseev, Artem; Ledneva, Galina

2013-04-01

Continental margin of Northeastern Asia includes many island arc terranes that differ in age and tectonic position. Two convergent margins are reconstructed for Late Jurassic - Early Cretaceous time: Uda-Murgal and Alazeya - Oloy island arc systems. A long tectonic zone composed of Upper Jurassic to Lower Cretaceous volcanic and sedimentary rocks is recognized along the Asian continent margin from the Mongol-Okhotsk thrust-fold belt on the south to the Chukotka Peninsula on the north. This belt represents the Uda-Murgal arc, which was developed along the convergent margin between Northeastern Asia and Northwestern Meso-Pacific. Several segments are identified in this arc based upon the volcanic and sedimentary rock assemblages, their respective compositions and basement structures. The southern and central parts of the Uda-Murgal island arc system were a continental margin belt with heterogeneous basement represented by metamorphic rocks of the Siberian craton, the Verkhoyansk terrigenous complex of Siberian passive margin and the Koni-Taigonos late Paleozoic to early Mesozoic island arc with accreted oceanic terranes. At the present day latitude of the Pekulney and Chukotka segments there was an ensimatic island arc with relicts of the South Anyui oceanic basin in backarc basin. Alazeya-Oloy island arc systems consists of Paleozoic and Mesozoic complexes that belong to the convergent margin between Northeastern Asia and Proto-Artic Ocean. It separated structures of the North American and Siberian continents. The Siberian margin was active whereas the North American margin was passive. The Late Jurassic was characterized by termination of a spreading in the Proto-Arctic Ocean and transformation of the latter into the closing South Anyui turbidite basin. In the beginning the oceanic lithosphere and then the Chukotka microcontinent had been subducted beneath the Alazeya-Oloy volcanic belt

An early bird from Gondwana: Paleomagnetism of Lower Permian lavas from northern Qiangtang (Tibet) and the geography of the Paleo-Tethys

NASA Astrophysics Data System (ADS)

Song, Peiping; Ding, Lin; Li, Zhenyu; Lippert, Peter C.; Yue, Yahui

2017-10-01

The origin of the northern Qiangtang block and its Late Paleozoic-Early Mesozoic drift history remain controversial, largely because paleomagnetic constraints from pre-Mesozoic units are sparse and of poor quality. In this paper, we provide a robust and well-dated paleomagnetic pole from the Lower Permian Kaixinling Group lavas on the northern Qiangtang block. This pole suggests that the northern Qiangtang block had a paleolatitude of 21.9 ± 4.7 °S at ca. 296.9 ± 1.9 Ma. These are the first volcanic-based paleomagnetic results from pre-Mesozoic rocks of the Qiangtang block that appear to average secular variation accurately enough to yield a well-determined paleolatitude estimate. This new pole corroborates the hypothesis, first noted on the basis of less rigorous paleomagnetic data, the presence of diamictites, detrital zircon provenance records, and faunal assemblages, that the northern Qiangtang block rifted away from Gondwana prior to the Permian. Previous studies have documented that the northern Qiangtang block accreted to the Tarim-North China continent by Norian time. We calculate a total northward drift of ca. 7000 km over ca. 100 myr, which corresponds to an average south-north plate velocities of ∼7.0 cm/yr. Our results do not support the conclusion that northern Qiangtang has a Laurasian affinity, nor that the central Qiangtang metamorphic belt is an in situ Paleo-Tethys suture. Our analysis, however, does not preclude paleogeographies that interpret the central Qiangtang metamorphic belt as an intra-Qiangtang suture that developed at southernly latitudes outboard of the Gondwanan margin. We emphasize that rigorous paleomagnetic data from Carboniferous units of northern Qiangtang and especially upper Paleozoic units from southern Qiangtang can test and further refine these paleogeographic interpretations.

The structural evolution of the Ghadames and Illizi basins during the Paleozoic, Mesozoic and Cenozoic: Petroleum implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gauthier, F.J.; Boudjema, A.; Lounis, R.

1995-08-01

The Ghadames and Illizi basins cover the majority of the eastern Sahara of Algeria. Geologicaly, this part of the Central Saharan platform has been influenced by a series of structural arches and {open_quotes}moles{close_quotes} (continental highs) which controlled sedimentation and structure through geologic time. These features, resulting from and having been affected by nine major tectonic phases ranging from pre-Cambrian to Tertiary, completely bound the Ghadames and Illizi Basins. During the Paleozoic both basins formed one continuous depositional entity with the Ghadames basin being the distal portion of the continental sag basin where facies and thickness variations are observed over largemore » distances. It is during the Mesozoic-Cenozoic that the Ghadames basin starts to evolve differently from the Illizi Basin. Eustatic low-stand periods resulted in continental deposition yielding the major petroleum-bearing reservoir horizons (Cambrian, Ordovician, Siluro-Devonian and Carboniferous). High-stand periods corresponds to the major marine transgressions covering the majority of the Saharan platform. These transgressions deposited the principal source rock intervals of the Silurian and Middle to Upper Devonian. The main reservoirs of the Mesozoic and Cenozoic are Triassic sandstone sequences which are covered by a thick evaporite succession forming a super-seal. Structurally, the principal phases affecting this sequence are the extensional events related to the breakup of Pangea and the Alpine compressional events. The Ghadames and Illizi basins, therefore, have been controlled by a polphase tectonic history influenced by Pan African brittle basement fracturing which resulted in complex structures localized along the major basin bounding trends as well as several subsidiary trends within the basin. These trends, as demonstrated with key seismic data, have been found to contain the majority of hydrocarbons trapped.« less

Tectonic insight based on anisotropy of magnetic susceptibility and compaction studies in the Sierras Australes thrust and fold belt (southwest Gondwana boundary, Argentina)

NASA Astrophysics Data System (ADS)

Arzadún, Guadalupe; Tomezzoli, Renata N.; Cesaretti, Nora N.

2016-04-01

The Sierras Australes fold and thrust belt (Buenos Aires Province, Argentina) was in the southwestern Gondwanaland margin during the Paleozoic. The Tunas Formation (Permian) is exposed along the eastern part of it and continues eastward beneath the Claromecó Basin. Anisotropy of magnetic susceptibility (AMS) and compaction studies are described and compared with previous paleomagnetic studies with the aim of determining direction and magnitude of the main stresses acting during the sedimentation of the Tunas Formation. The anisotropy ellipsoids are triaxial with oblate or prolate shapes, reflecting different stages of layer parallel shortening during the evolution of the basin. Kmax axes trend NW-SE, parallel to the fold axes, while Kmin move from a horizontal (base) to a vertical orientation at the top of the succession, showing a change from a tectonic to almost a sedimentary fabric. The magnitude of anisotropy and compaction degree decreases toward the top of the succession. The AMS results are consistent with the outcrop structural observations and the compaction and paleomagnetic data. Regional pattern indicates a compression from the SW along this part of Gondwana, with a migration of the orogenic front and attenuation toward the NE in the foreland basin during the Upper Paleozoic. This deformation, locally assigned to the San Rafael noncollisional orogenic phase, is the result of the latitudinal movements toward the Equator of Gondwana (southern plates) and Laurentia (northern plates) during the Permian. This movement is the result of a rearrangement of the microplates that collided with Gondwana during the Late Devonian, to configure Pangea during the Triassic.

Late Paleozoic to Jurassic chronostratigraphy of coastal southern Peru: Temporal evolution of sedimentation along an active margin

NASA Astrophysics Data System (ADS)

Boekhout, F.; Sempere, T.; Spikings, R.; Schaltegger, U.

2013-11-01

We present an integrated geochronological and sedimentological study that significantly revises the basin and magmatic history associated with lithospheric thinning in southern coastal Peru (15-18°S) since the onset of subduction at ˜530 Ma. Until now, estimating the age of the sedimentary and volcanic rocks has heavily relied on paleontologic determinations. Our new geochronological data, combined with numerous field observations, provide the first robust constraints on their chronostratigraphy, which is discussed in the light of biostratigraphical attributions. A detailed review of the existing local units simplifies the current stratigraphic nomenclature and clarifies its absolute chronology using zircon U-Pb ages. We observe that the Late Paleozoic to Jurassic stratigraphy of coastal southern Peru consists of two first-order units, namely (1) the Yamayo Group, a sedimentary succession of variable (0-2 km) thickness, with apparently no nearby volcanic lateral equivalent, and (2) the overlying Yura Group, consisting of a lower, 1-6 km-thick volcanic and volcaniclastic unit, the Chocolate Formation, and an upper, 1-2 km-thick sedimentary succession that are in markedly diachronous contact across the coeval arc and back-arc. We date the local base of the Chocolate Formation, and thus of the Yura Group, to 216 Ma, and show that the underlying Yamayo Group spans a >110 Myr-long time interval, from at least the Late Visean to the Late Triassic, and is apparently devoid of significant internal discontinuities. The age of the top of the Chocolate Formation, i.e. of the volcanic arc pile, varies from ˜194 Ma to less than ˜135 Ma across the study area. We suggest that this simplified and updated stratigraphic framework can be reliably used as a reference for future studies.

Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system

USGS Publications Warehouse

Rostad, C.E.; Pereira, W.E.; Hult, M.F.

1985-01-01

Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Groundwater contamination by these toxic compounds may pose an environmental health hazard in nearby public water-supply wells. Fluid samples from this aquifer developed two phases upon settling: an upper aqueous phase, and a lower oily-tar phase. After separating the phases, polycyclic aromatic compounds in each phase were isolated using complexation with N-methyl-2-pyrrolidone and identified by fused-silica capillary gas chromatography/mass spectrometry. Thirty-one of the polycyclic aromatic compounds were chosen for further study from four different classes: 12 polycyclic aromatic hydrocarbons, 10 nitrogen heterocycles, 5 sulfur heterocycles, and 4 oxygen heterocycles. Within each compound class, the tar/water partition coefficients of these compounds were reasonably comparable with the respective n-octanol/water partition coefficient.

Tectonic analysis of mine tremor mechanisms from the Upper Silesian Coal Basin

NASA Astrophysics Data System (ADS)

Sagan, Grzegorz; Teper, Lesław; Zuberek, Waclaw M.

1996-07-01

Fault network of the Upper Silesian Coal Basin (USCB) is built of sets of strike-slip, oblique-slip and dip-slip faults. It is a typical product of force couple which acts evenly with the parallel of latitude, causing horizontal and anti-clockwise movement of rock-mass. Earlier research of focal mechanisms of mine tremors, using a standard fault plane solution, has shown that some events are related to tectonic directions in main structural units of the USCB. An attempt was undertaken to analyze the records of mine tremors from the period 1992 1994 in the selected coal fields. The digital records of about 200 mine tremors with energy larger than 1×104 J ( M L >1.23) were analyzed with SMT software for seismic moment tensor inversion. The decomposition of seismic moment tensor of mine tremors was segmented into isotropic (I) part, compensated linear vector dipole (CLVD) part and double-couple (DC) part. The DC part is prevalent (up to 70%) in the majority of quakes from the central region of the USCB. A group of mine tremors with large I element (up to 50%) can also be observed. The spatial orientation of the fault and auxiliary planes were obtained from the computations for the seismic moment DC part. Study of the DC part of the seismic moment tensor made it possible for us to separate the group of events which might be acknowledged to have their origin in unstable energy release on surfaces of faults forming a regional structural pattern. The possible influence of the Cainozoic tectonic history of the USCB on the recent shape of stress field is discussed.

Use of reconstituted waters to evaluate effects of elevated major ions associated with mountaintop coal mining on freshwater invertebrates

USGS Publications Warehouse

Kunz, James L.; Conley, Justin M.; Buchwalter, David B.; ,; Teresa, J.; Kemble, Nile E.; Wang, Ning; Ingersoll, Christopher G.

2013-01-01

In previous laboratory chronic 7-d toxicity tests conducted with the cladoceran Ceriodaphnia dubia, surface waters collected from Appalachian sites impacted by coal mining have shown toxic effects associated with elevated total dissolved solids (TDS). The objective of the present study was to evaluate the effects of elevated major ions in chronic laboratory tests with C. dubia (7-d exposure), a unionid mussel (Lampsilis siliquoidea; 28-d exposure), an amphipod (Hyalella azteca; 28-d exposure), and a mayfly (Centroptilum triangulifer; 35-d exposure) in 3 reconstituted waters designed to be representative of 3 Appalachian sites impacted by coal mining. Two of the reconstituted waters had ionic compositions representative of alkaline mine drainage associated with mountaintop removal and valley fill-impacted streams (Winding Shoals and Boardtree, with elevated Mg, Ca, K, SO4, HCO3), and a third reconstituted water had an ionic composition representative of neutralized mine drainage (Upper Dempsey, with elevated Na, K, SO4, and HCO3). The waters with similar conductivities but, with different ionic compositions had different effects on the test organisms. The Winding Shoals and Boardtree reconstituted waters were consistently toxic to the mussel, the amphipod, and the mayfly. In contrast, the Upper Dempsey reconstituted water was toxic to the mussel, the amphipod, and the cladoceran but was not toxic to the mayfly. These results indicate that, although elevated TDS can be correlated with toxicity, the specific major ion composition of the water is important. Moreover, the choice of test organism is critical, particularly if a test species is to be used as a surrogate for a range of faunal groups.

Paleozoic tectonics of the Ouachita Orogen through Nd isotopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gleason, J.D.; Patchett, P.J.; Dickinson, W.R.

1992-01-01

A combined isotopic and trace-element study of the Late Paleozoic Ouachita Orogenic belt has the following goals: (1) define changing provenance of Ouachita sedimentary systems throughout the Paleozoic; (2) constrain sources feeding into the Ouachita flysch trough during the Late Paleozoic; (3) isolate the geochemical signature of proposed colliding terranes to the south; (4) build a data base to compare with possible Ouachita System equivalents in Mexico. The ultimate aim is to constrain the tectonic setting of the southern margin of North America during the Paleozoic, with particular emphasis on collisional events leading to the final suturing of Pangea. Ndmore » isotopic data identify 3 distinct groups: (1) Ordovician passive margin sequence; (2) Carboniferous proto-flysch (Stanley Fm.), main flysch (Jackfork and Atoka Fms.) and molasse (foreland Atoka Fm.); (3) Mississippian ash-flow tuffs. The authors interpret the Ordovician signature to be essentially all craton-derived, whereas the Carboniferous signature reflects mixed sources from the craton plus orogenic sources to the east and possibly the south, including the evolving Appalachian Orogen. The proposed southern source is revealed by the tuffs to be too old and evolved to be a juvenile island arc terrane. They interpret the tuffs to have been erupted in a continental margin arc-type setting. Surprisingly, the foreland molasse sequence is indistinguishable from the main trough flysch sequence, suggesting the Ouachita trough and the craton were both inundated with sediment of a single homogenized isotopic signature during the Late Carboniferous. The possibility that Carboniferous-type sedimentary dispersal patterns began as early as the Silurian has important implications for the tectonics and paleogeography of the evolving Appalachian-Ouachita Orogenic System.« less

Evaluation of undiscovered natural gas in the Upper Cretaceous Ferron Coal/Wasatch Plateau Total Petroleum System, Wasatch Plateau and Castle Valley, Utah

USGS Publications Warehouse

Henry, M.E.; Finn, T.M.

2003-01-01

The Total Petroleum System approach was used to estimate undiscovered gas potential of the Wasatch Plateau and Castle Valley, central Utah. The Ferron Coal/Wasatch Plateau Total Petroleum System was geologically defined and subdivided into seven assessment units, six of which were formally evaluated. Geologic data considered in defining the assessment unit boundaries included thermal maturity, coal presence and thickness, overburden thickness, and faulting intensity. Historical production data were also used to estimate volumes of gas from undrilled areas. The one conventional assessment unit includes almost the entire area of the petroleum system and is characterized by known accumulations that occur in structural or combination traps in sandstone reservoirs. The estimated undiscovered conventional producible gas that may be added to reserves of this unit ranges from a low (F95) of 14.8 billion cubic feet (BCFG) [419 million cubic meters (Mm3)] of gas to a high (F5) of 82 BCFG [2321 Mm3] and a mean value of 39.9 BCFG [1130 Mm3]. Continuous gas accumulations are those in which the entire assessment unit is considered to be gas-charged. Within these assessment units, there may be wells drilled that are not economic successes but all are expected to contain gas. Coalbed gas is in this continuous category. Mean estimates of undiscovered gas for the five continuous assessment units are: (1) Northern Coal Fairway/Drunkards Wash-752.3 BCFG [21,323 Mm3]; (2) Central Coal Fairway/Buzzard Bench-536.7 BCFG [15,194 Mm3]; (3) Southern Coal Fairway-152.6 BCFG [4320 Mm3]; (4) Deep (6000 feet plus) Coal and Sandstone-59.1 BCFG [1673 Mm3]; (5) Southern Coal Outcrop-10.6 BCFG [300 Mm3]; and Joes Valley and Musinia Grabens-not assessed.The mean estimate of undiscovered gas for the entire TPS is 1551.2 BCFG [43,914 Mm3]. There is a 95% chance that at least 855.7 BCFG [24,225 Mm3] and a 5% chance that at least 2504 BCFG [70,888 Mm3] of undiscovered producible gas remain in the TPS. ?? 2003 Published by Elsevier B.V.

Water Redistribution, Temperature Change and CO2 Diffusion of Reconstruction Soil Profiles Filled with Gangue in Coal Mining Areas

NASA Astrophysics Data System (ADS)

Wang, S.; Zhan, H.; Chen, X.; Hu, Y.

2017-12-01

There were a great many projects of reconstruction soil profile filled with gangue to restore ecological environment and land resources in coal mining areas. A simulation experimental system in laboratory was designed for studying water transport and gas-heat diffusion of the reconstruction soil as to help the process of engineering and soil-ripening technology application. The system could be used for constantly measuring soil content, temperature and soil CO2 concentration by laid sensors and detectors in different depth of soil column. The results showed that soil water infiltration process was slowed down and the water-holding capacity of the upper soil was increased because of good water resistance from coal gangue layer. However, the water content of coal gangue layer, 10% approximately, was significantly lower than that of topsoil for the poor water-holding capacity of gangue. The temperature of coal gangue layer was also greater than that of soil layer and became easily sustainable temperature gradient under the condition with heating in reconstruction soil due to the higher thermal diffusivity from gangue, especially being plenty of temperature difference between gangue and soil layers. The effects of heated from below on topsoil was small, which it was mainly influenced from indoor temperature in the short run. In addition, the temperature changing curve of topsoil is similar with the temperature of laboratory and its biggest fluctuation range was for 2.89°. The effects of aerating CO2 from column bottom on CO2 concentration of topsoil soil was also very small, because gas transport from coal gangue layers to soil ones would easily be cut off as so to gas accumulated below the soil layer. The coal gangue could have a negative impact on microbial living environment to adjacent topsoil layers and declined microorganism activities. The effects of coal gangue on topsoil layer were brought down when the cove soil thickness was at 60 cm. And the influences gradually would be weakened with the thickness increasing.

Shear zones of the Verkhoyansk fold-and-thrust belt, Northeast Russia

NASA Astrophysics Data System (ADS)

Fridovsky, Valery; Polufuntikova, Lena

2017-04-01

The Verkhoyansk fold-and-thrust belt is situated on the submerged eastern margin of the North Asian craton, and is largely composed of the Ediacaran - Middle Paleozoic carbonate and the Upper Paleozoic-Mesozoic terrigenous rocks. The Upper Carboniferous - Jurassic sediments constitute the Verkhoyansk terrigenous complex containing economically viable orogenic gold deposits. The structure of the belt is mainly controlled by thrusts and associated diagonal strike slips. Linear concentric folds are common all over the area of the belt. Shear zones with associated similar folds are confined to long narrow areas. Shear zones were formed during the early stages of the Oxfordian-Kimmeridgian collisional and accretionary events prior to the emplacement of large orogenic granitoid plutons. The main ore-controlling structures are shear zones associated with slaty cleavage, shear folds, mullion- and boudinage-structures, and transposition features. The shear zones are listric-type, and represent branches of a detachment structure, which is assumed to be present at the base of the Verkhoyansk fold-and-thrust belt. A vertical zonation of shear zones is correlated with the distance to the detachment. Changes in the dip angle of the shear zones (as indicated mainly by cleavage), structural paragenesis, the degree of microdeformation of the host rocks, and the type of ore-controlling structures can be clearly observed in the direction away from the detachment. Structural zoning is evidenced, among other things, by changing morphologic types of microstructures and by strain-indicators of the degree of rock metamorphism. Four morphologic types of microstructures are identified. The first platy-shear type is characterized by aggregate cleavage and the coefficient of deformation (Cd) of single grains from 1.0 to 2.0. Irregular angular fragments of variously oriented grains can be observed in thin sections. The second shear-cataclastic morphologic type (Cd from 2.0 to 3.0) exhibits combined aggregate and intergranular cleavage. The third cataclastic-segregation morphologic type (Cd from 3.0 to 4.5) is distinguished by a wide distribution of lentelliptical grains of rock-forming minerals in a finely-crystalline matrix and by intergranular cleavage. The rocks of the fourth segregation-striate morphologic type (Cd >5.0) contain lenticular segregations of quartz and feldspar in an intensely linearized mylonite groundmass.

The African and Pacific Superplume Structures Constrained by Assembly and Breakup of Pangea

NASA Astrophysics Data System (ADS)

Zhang, N.; Zhong, S.; Leng, W.; Li, Z.

2009-12-01

Seismic tomography studies indicate that the Earth’s mantle structure is characterized by African and Pacific seismically slow velocity anomalies (i.e., superplumes) and circum-Pacific seismically fast anomalies (i.e., a globally spherical harmonic degree-2 structure). McNamara and Zhong (2005) have demonstrated that the African and Pacific superplume structures result from dynamic interaction between mantle convection and surface plate motion history in the last 120 Ma. However, their models produce slightly stronger degree 3 structure than degree 2 near the CMB. Here, we construct a proxy model of plate motions for the African hemisphere for the last 450 Ma since the Early Paleozoic using the paleogeographic reconstruction of continents constrained by paleomagnetic and geological observations. Using this proxy model for plate motion history as the time-dependent surface boundary conditions for a 3-dimensional spherical model of thermochemical mantle convection, we calculate the present-day mantle structure and explore the evolution of mantle structures since the Early Paleozoic. Our model calculations reproduce well the present-day mantle structure including the African and Pacific superplumes. The power spectra of our calculated present-day temperature field shows that the strongest power occurs at degree 2 in the lower mantle while in the upper mantle the strongest power is at degree 3. The degree correlation between tomography model S20RTS and our calculated temperature field shows a high correlation at the degree 1 and degree 2 in the lower mantle while the upper mantle and the short wavelength structures do not correlate well. The summed degree correlation for the lower mantle shows a relatively good correlation for the bottom 300 km of the mantle but the correlation is significantly reduced at depth 600 km above the CMB. For the evolution of mantle structures, we focus on the evolution of the African superplume. Our results suggest that the mantle in the African hemisphere before the assembly of Pangea is predominated by the cold downwelling structure resulting from plate convergence between Gondwana and Laurussia and the cold Africa hemisphere changes to hot due to the return flows from the circum-Pangea subduction after Pangea formation. Based on our results, we suggest that the African superplume structure may be formed no earlier than ~230 Ma ago (i.e., ~100 Ma after the assembly of Pangea).

Heat flow and near-surface radioactivity in the Australian continental crust

USGS Publications Warehouse

Sass, J.H.; Jaeger, J.C.; Munroe, Robert J.

1976-01-01

Heat-flow data have been obtained at 44 sites in various parts of Australia. These include seven sites from the old (~ 2500 m.y.) Precambrian shield of Western Australia, seventeen from the younger (~ 600- 2000 m.y.) Precambrian rocks of South Australia, the Northern Territory, and Queensland, and twenty within the eastern Paleozoic and younger rocks. Thirty of the sites are located where no previous heat-flow data existed, and the remainder provide significant extensions or refinements of areas previously studied. Where the holes studied penetrated the crystalline basement rocks, or where the latter rocks were exposed within a few kilometers of the holes, the upper crustal radiogenic heat production has been estimated based on gamma-ray spectrometric determinations of U, Th, and K abundances. Three heat-flow provinces are recognized in Australia based on the linear relation (q = q* + DA0 ) between heat flow q and surface radioactivity A0. New data from the Western Australian shield support earlier studies showing that heat flow is low to normal with values ranging from 0.7 to 1.2 hfu and with the majority of values less than 1.0 hfu, and the parameters q* = 0.63 hfu and 0 = 4.5 km determined previously were confirmed. Heat flow in the Proterozoic shield of central Australia is quite variable, with values ranging between about l and 3 hfu. This variability is attributed mainly to variations in near-surface crustal radioactivity. The parameters of the heat-flow line are q* = 0.64 hfu and 0 = 11.1 km and moderately high temperatures are predicted for the lower crust and upper mantle. Previous suggestions of a band of l ow- to - normal heat flow near the coast in eastern Australia were confirmed in some areas, but the zone is interrupted in at least one region (the Sydney Basin), where heat flow is about 2.0 hfu over a large area. The reduced heat flow, q*, in the Paleozoic intrusive rocks of eastern Australia varies from about 0.8 to 2.0 hfu . This variability might be related to thermal transients associated with Late Tertiary and younger volcanic and tectonic activity, even though the relation between heat-flow values and the age of volcanism is not a simple one. Parts of the high heat-flow area in the southeast might be exploitable for geothermal energy.

Redescription of Bellerophon asiaticus Wirth (Early Triassic: Gastropoda) from China, and a survey of Triassic Bellerophontacea.

USGS Publications Warehouse

Yochelson, E.Y.; Yin, Hongfu

1985-01-01

The bilaterally symmetrical gastropod Bellerophon asiaticus Wirth is redescribed from specimens collected in Guizhou Province, PRC. The species is reassigned to Retispira, a common late Paleozoic taxon. Retispira is another example of a Paleozoic gastropod genus that crossed the era boundary. Associated pelecypods that date these Guizhou occurrences as Early Triassic are well known species in PRC and are illustrated. Both Bellerophon and Euphemites probably occur in the Early Triassic, though the quality of illustrations leaves some uncertainty; the existence of Stachella in the Triassic is more problematic. There was no dramatic reduction of the Bellerophontacea from their abundance and diversity in the Permian. It may be a general phenomenon that most late Paleozoic family-level and many generic-level taxa of gastropods were unaffected by the late Permian 'crisis'. from Authors

Influence of rock composition on the geochemistry of stream and spring waters from mountainous watersheds in the Gunnison, Uncompahgre, and Grand Mesa National Forests, Colorado

USGS Publications Warehouse

Miller, William Roger

2002-01-01

The ranges of geochemical baselines for stream and spring waters were determined and maps were constructed showing acid-neutralizing capacity and potential release of total dissolved solids for streams and spring waters for watersheds underlain by each of ten different rock composition types in the Gunnison, Uncompahgre, and Grand Mesa National Forests, Colorado (GMUG). Water samples were collected in mountainous headwater watersheds that have comparatively high precipitation and low evapotranspiration rates and that generally lack extensive ground-water reservoirs. Mountainous headwaters react quickly to changes in input of water from rain and melting snow and they are vulnerable to anthropogenic impact. Processes responsible for the control and mobility of elements in the watersheds were investigated. The geochemistry of water from the sampled watersheds in the GMUG, which are underlain by rocks that are relatively unmineralized, is compared to the geochemistry of water from the mineralized Redcloud Peak area. The water with the highest potential for release of total dissolved solids is from watersheds that are underlain by Paleozoic sedimentary rocks; that high potential is caused primarily by gypsum in those rocks. Water that has the highest acid-neutralizing capacity is from watersheds that are underlain by Paleozoic sedimentary rocks. The water from watersheds underlain by the Mancos Shale has the next highest acid-neutralizing capacity. Water that has the lowest acid-neutralizing capacity is from watersheds that are underlain by Tertiary ash-flow tuff. Tertiary sedimentary rocks containing oil shale, the Mesavede Formation containing coal, and the Mancos Shale all contain pyrite with elevated metal contents. In these mountainous head-water areas, water from watersheds underlain by these rock types is only slightly impacted by oxidation of pyrite, and over-all it is of good chemical quality. These geochemical baselines demonstrate the importance of rock composition in determining the types of waters that are in the headwater areas. The comparison of these geochemical baselines to later geochemical base-lines will allow recognition of any significant changes in water quality that may occur in the future.

Investigation of subsidence event over multiple seam mining area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kohli, K.K.

1999-07-01

An investigation was performed to determine the sequence of events which caused the 1987 surface subsidence and related damage to several homes in Walker County, Alabama, USA. Surface affects compared to mine maps indicated the subsidence to be mine related. However, two coal seams had been worked under this area. The upper seam, the American seam, ranged from 250 to 280 feet beneath the surface in the area in question. It was mined-out before 1955 by room-and-pillar method leaving in place narrow-long pillars to support the overburden strata, and abandoned in 1955. The lower seam, the Mary Lee seam, rangedmore » from 650 to 700 feet beneath the surface. The Mary Lee seam had been abandoned in 1966 and subsequently became flooded. The dewatering of the Mary Lee seam workings in 1985 caused the submerged pillars to be exposed to the atmosphere. Due to multiple seam mining and the fact that workings had been inundated then dewatered, a subsurface investigation ensued to determine the sequence and ultimate cause of surface subsidence. Core sample tests with fracture analysis in conjunction with down-the-hole TV camera inspections provided necessary information to determine that the subsidence started in the lower seam and progressed through the upper coal seam to the surface. Evidence from the investigation program established that dewatering of the lower seam workings caused the marginally stable support pillars and the roof to collapse. This failure triggered additional subsidence in the upper seam which broadened the area of influence at the surface.« less

Sequential development of structural heterogeneity in the Granny Creek oil field of West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, T.H.; Zheng, L.; Shumaker, R.C.

1993-08-01

Analysis of Vibroseis and weight-drop seismic data over the Granny Creek oil field in the Appalachian foreland of West Virginia indicates that the field's development has been effected by episodic Paleozoic reactivation of fault blocks rooted in the Precambrian crystalline basement. The imprint of structures associated with the Rome trough penetrates the overlying Paleozoic sedimentary cover. Reactivation histories of individual fault blocks vary considerably throughout the Paleozoic. In general, the relative displacement of these basement fault blocks decrease exponentially during the Paleozoic; however, this pattern is interrupted by periods of increased tectonic activity and relative inversion of offsets along somemore » faults. The distribution of late-stage detached structures during the Alleghenian orogeny also appears, in part, to be controlled by mechanical anisotrophy within the detached section related to the reactivation of deeper structures in the crystalline basement. The net effect is a complex time-variable pattern of structures that partly controls the location of the reservoir and heterogeneity within the geometric framework of the reservoir. Structural heterogeneity in the Granny Creek area is subdivided on the basis of scale into structures associated with variations of oil production within the reservoir. Variations of production within the field are related, in part, to small detached structures and reactivated basement faults.« less

The Paleozoic ichthyofauna of the Amazonas and Parnaíba basins, Brazil

NASA Astrophysics Data System (ADS)

Figueroa, Rodrigo Tinoco; Machado, Deusana Maria da Costa

2018-03-01

The Brazilian Paleozoic ichthyofauna from the Parnaíba and Amazonas basins regard a sparsely known diversity, including chondrichthyans and acanthodians, besides some osteichthyan remains. This work proposes a revision of the fossil material from these two sedimentary basins and synthesizes the morphological aspect of such material trying to understand the influences of those fossils to the paleontology of the region, comparing the Brazilian fossils with other gondwanan faunas. The Brazilian Paleozoic fish fauna shows great resemblance to those of Bolivia, especially during the Devonian. Many of the Acanthodian spines from the Manacapuru Formation (Amazonas Basin), and the Pimenteira Formation (Parnaíba Basin), are comparable to the taxa found in Bolivia. The lack of more Placoderm remains in the Brazilian outcrops is similar to the low diversity of this group in Bolivia, when compared to other South American and Euramerican localities. The most diverse Brazilian ichthyofauna is encountered in the Permian Pedra de Fogo Formation where numerous chondrichthyans and 'paleopterygians' remains are found, together with dipnoans and actinistians. Despite the apparent lack of more representative Paleozoic ichthyofaunas in Brazil, the available material that ranges from Lower Devonian to early Permian from Brazil bears important taxa that could address valuable taxonomic and biogeographic informations.

Applied geochemistry, geology and mineralogy of the northernmost Carlin trend, Nevada

USGS Publications Warehouse

Theodore, T.G.; Kotlyar, B.B.; Singer, D.A.; Berger, V.I.; Abbott, E.W.; Foster, A.L.

2003-01-01

Investigations in the northernmost Carlin trend were undertaken to advance understanding of the geochemical signatures and genesis of precious metal deposits in the trend. Two fundamental geologic relationships near the trend significantly affect regional geochemical distributions: a remarkably intact lower Paleozoic stratigraphic sequence of siliceous rocks in the upper plate of the middle Paleozoic Roberts Mountains thrust, and the widespread repetition of rocks high in the upper plate during late Paleozoic thrusting that thickens the cover above mineralized rock in the lower plate. A compilation of previously published chemical analyses of 440 stream sediment samples and 115 rocks from two 7 1/2-minute quadrangles, as well as new chemical analyses of approximately 1,000 drill core samples in a 1,514 m (4,970 ft) hole through the Rodeo Creek deposit were used to construct three-dimensional element distribution models that highlight metal zonation in the mineralized systems. The Rodeo Creek deposit comprises deep Ag base-metal ?? Au-mineralized rock below the Roberts Mountains thrust and contains an unusually high Ag/Au ratio greater than 30. Stacked geochemical halos related to the deposit are confined to the lower plate of the Roberts Mountains thrust and include two horizons of Hg, Cu, and Zn anomalies-as much as 180 m above the deposit-that mostly result from mercurian sphalerite. Extremely subtle indications of mineralization in the upper plate of the Roberts Mountains thrust above the deposit include arsenopyrite overgrowths on small pyrite crystals in 50- to 75-??m-wide clay-carbonate veinlets that lack alteration halos, arsenical rims on small disseminated crystal of recrystallized diagenetic pyrite, and partial replacement of diagenetic pyrite by tennantite. Some of these minerals contain anomalously high Au. However, these As-(Au)-bearing rocks most likely represent another locus of largely untested mineralized rock rather than distal halos related to either the Rodeo Creek or the nearby Dee and Storm gold deposits. Application of micromineralogic techniques helped to identify mineral assemblages that are specific to mineralization and provided an empirical foundation for interpretations of geochemical halos in the Carlin trend. District-scale geochemical patterns of several elements in stream sediments and surface rocks coincide with the northernmost Carlin trend and can be used to explore for Carlin-type deposits. Concentrations of elevated As and Sb in stream sediments (as much as 54 ppm As) have northwest-elongate lobate patterns that clearly outline the trend across a width of approximately 4 km. Arsenic contents of exposed rocks (as much as 90 ppm As) strongly correlate with As contents of derivative stream sediments, and rock contents of Sb show a somewhat lesser but nonetheless strong and similar correspondence. Factor analysis of stream-sediment data shows that those factor scores that are correlated with As, Sb, Au, and Pb also are high along the trend and suggest that mineralized rocks may be present. Although As was not detected by scanning electron microscope-energy dispersive spectrometer (SEM-EDS) studies in heavy mineral concentrates of high-As stream sediments in the Carlin trend, X-ray absorption near-edge spectra (XANES) of selected light fractions of stream sediment samples indicate that Al-bearing phases, such as gibbsite, amorphous Al oxyhydroxides, or aluminosilicate clay minerals host most of the As(V). The best fit, visually and in terms of the lowest residual, was obtained by a model compound of As(V) sorbed to gibbsite. Thus, most As in stream sediments derived from altered rock within the Carlin trend apparently is contained in light fractions. The geochemical character of young, unconsolidated, postmineral deposits that cover mineralized rocks on the Carlin trend partly results from mineralized sources along the trend. Concentration of As in the Miocene Carlin Formation shows an exceptio

Diagenesis and porosity evolution of tight sand reservoirs in Carboniferous Benxi Formation, Southeast Ordos Basin

NASA Astrophysics Data System (ADS)

Hu, Peng; Yu, Xinghe; Shan, Xin; Su, Dongxu; Wang, Jiao; Li, Yalong; Shi, Xin; Xu, Liqiang

2016-04-01

The Ordos Basin, situated in west-central China, is one of the oldest and most important fossil-fuel energy base, which contains large reserves of coal, oil and natural gas. The Upper Palaeozoic strata are widely distributed with rich gas-bearing and large natural gas resources, whose potential is tremendous. Recent years have witnessed a great tight gas exploration improvement of the Upper Paleozoic in Southeastern Ordos basin. The Carboniferous Benxi Formation, mainly buried more than 2,500m, is the key target strata for hydrocarbon exploration, which was deposited in a barrier island and tidal flat environment. The sandy bars and flats are the favorable sedimentary microfacies. With an integrated approach of thin-section petrophysics, constant velocity mercury injection test, scanning electron microscopy and X-ray diffractometry, diagenesis and porosity evolution of tight sand reservoirs of Benxi Formation were analyzed in detail. The result shows that the main lithology of sandstone in this area is dominated by moderately to well sorted quartz sandstone. The average porosity and permeability is 4.72% and 1.22mD. The reservoirs of Benxi Formation holds a variety of pore types and the pore throats, with obvious heterogeneity and poor connection. Based on the capillary pressure curve morphological characteristics and parameters, combined with thin section and phycical property data, the reservoir pore structure of Benxi Formation can be divided into 4 types, including mid pore mid throat type(I), mid pore fine throat type(II), small pore fine throat type(III) and micro pro micro throat type(Ⅳ). The reservoirs primarily fall in B-subsate of middle diagenesis and late diagenesis, which mainly undergo compaction, cmentation, dissolution and fracturing process. Employing the empirical formula of different sorting for unconsolideated sandstone porosity, the initial sandstone porosity is 38.32% on average. Quantitative evaluation of the increase and decrease of porosity caused by different diagenesis reveals that mechanical compaction and chemical cementation are the main mechanisms for destroying primary pores, which contribute 19.61% and 8.75% to the loss of primary posoity, respectively. Dissolution of volcanic fragments and feldspar increased reservoir porosity by 4.14%. The pores were occluded by late minerals and carbonate cements, resulting in a reduction of 9.38%. Overall, the dual influence of compaction and cementation is the key of the key, controlling formation of tight gas sandstone reservoirs. Keywords: diagenesis, porosity evolution, tight sandstone, Benxi Formation, Southeast Ordos Basin Acknowledgements: We greatfully acknowledge Yanchang Petroleum for providing the samples and data access and for permission to publish this work. The first author, Peng Hu, would like to thank the support from Prof. Xinghe Yu.

Water quality of the Swatara Creek Basin, PA

USGS Publications Warehouse

McCarren, Edward F.; Wark, J.W.; George, J.R.

1964-01-01

The Swatara Creek of the Susquehanna River Basin is the farthest downstream sub-basin that drains acid water (pH of 4.5 or less) from anthracite coal mines. The Swatara Creek drainage area includes 567 square miles of parts of Schuylkill, Berks, Lebanon, and Dauphin Counties in Pennsylvania.To learn what environmental factors and dissolved constituents in water were influencing the quality of Swatara Creek, a reconnaissance of the basin was begun during the summer of 1958. Most of the surface streams and the wells adjacent to the principal tributaries of the Creek were sampled for chemical analysis. Effluents from aquifers underlying the basin were chemically analyzed because ground water is the basic source of supply to surface streams in the Swatara Creek basin. When there is little runoff during droughts, ground water has a dominating influence on the quality of surface water. Field tests showed that all ground water in the basin was non-acidic. However, several streams were acidic. Sources of acidity in these streams were traced to the overflow of impounded water in unworked coal mines.Acidic mine effluents and washings from coal breakers were detected downstream in Swatara Creek as far as Harper Tavern, although the pH at Harper Tavern infrequently went below 6.0. Suspended-sediment sampling at this location showed the mean daily concentration ranged from 2 to 500 ppm. The concentration of suspended sediment is influenced by runoff and land use, and at Harper Tavern it consisted of natural sediments and coal wastes. The average daily suspended-sediment discharge there during the period May 8 to September 30, 1959, was 109 tons per day, and the computed annual suspended-sediment load, 450 tons per square mile. Only moderate treatment would be required to restore the quality of Swatara Creek at Harper Tavern for many uses. Above Ravine, however, the quality of the Creek is generally acidic and, therefore, of limited usefulness to public supplies, industries and recreation. In general, the quality of Swatara Creek improves after it mixes with water from the Upper Little and Lower Little Swatara Creeks, which converge with the main stream near Pine Grove. Jonestown is the first downstream location where Swatara Creek contains bicarbonate ion most of the time, and for the remaining downstream length of the stream, the concentration of bicarbonate progressively increases. Before the stream enters the Susquehanna River, chemical and diluting processes contributed by tributaries change the acidic calcium sulfate water, which characterizes the upper Swatara, to a calcium bicarbonate water.A major tributary to Swatara Creek is Quittapahilla Creek, which drains a limestone region and has alkaline characteristics. Effluents from a sewage treatment plant are discharged into this stream west of Lebanon. Adjacent to the Creek are limestone quarries and during the recovery of limestone, ground water seeps into the mining areas. This water is pumped to upper levels and flows over the land surface into Quittapahilla Creek. As compared with the 1940's, the quality of Swatara Creek is better today, and the water is suitable for more uses. In large part, this improvement is due to curtailment of anthracite coal mining and because of the controls imposed on new mines, stripping mines, and the related coal mining operations, by the Pennsylvania Sanitary Water Board. Thus, today (1962) smaller amounts of coal mine wastes are more effectively flushed and scoured away with each successive runoff during storms that affect the drainage basin. Natural processes neutralizing acid water in the stream by infiltration of alkaline ground water through springs and through the streambed are also indicated.

Coal resources of the Alton, Utah, EMRIA site

USGS Publications Warehouse

Bowers, William E.; Aigen, A.A.; Landis, Edwin R.

1976-01-01

The estimated original identified coal resources of the Alton, Utah, EMRIA (Energy Minerals Rehabilitation Inventory and Analysis) site--an area of about 3.6 square miles (9.3 square kilometres)--total almost 49 million tons (45 megatonnes). A larger area that surrounds and includes the Alton EMRIA site proper contains estimated original identified coal resources of almost 309 million tons (281 megatonnes). Of these estimated resources in the EMRIA site proper, almost 27 million tons (25 megatonnes) are in beds more than 10 feet thick (3 metres); these beds are overlain by less-than 200 feet (60 metres) of overburden. In the larger area around and including the EMRIA site, about 88.5 million tons (81 megatonnes) are in beds more than ten feet (3 metres) thick with less than 200 feet (60 metres) of overburden. All the estimated resources are in the Smirl zone in the upper part of the Dakota Formation of Cretaceous age. The coal has an apparent rank of subbituminous B, an average heating value of about 9,560 Btu, an average sulfur content of about 1.0 percent, and an average ash content of 7.2 percent. When compared with the average abundance of elements in the crust of the Earth as a whole, only selenium and boron were present in the Alton area coal samples in amounts an order of magnitude greater than the average crustal abundance. Beryllium, fluorine, nickel, zinc, and zirconium are all present in the Alton area samples in amounts that are about an order of magnitude less than the average crustal abundance.

Arrangement for controlled engagement of the tools of a mining machine with a mine face

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blumenthal, G.; Bollmann, A.

1981-07-28

An arrangement for controlled engagement of the tools of a coal planer, with a mine face comprises a scraper conveyor, provided on its front face directed toward the mine face with a guide rail guiding the coal planer for reciprocation along the mine face and a mechanism for tilting the conveyor and the coal planer about a substantially horizontal axis. The tilting mechanism is connected to the rear face of the conveyor and extends in its entirety rearwardly of the rear face of the latter. The tilting mechanism comprises a guide linkage pivotally connected at its front end to themore » rear face of the scraper conveyor while its rear end portion forms a housing for a fluid operated cylinder and piston unit, the piston rod of which is connected to a connecting rod guided by the guide linkage for movement in longitudinal direction and having an upwardly extending front section pivotally connected at its upper free end to the rear face of the scraper conveyor. The fluid operated cylinder-and-piston unit is thus considerably spaced from the scraper conveyor and the material transported thereby and especially coal dust raised during transport of the mined coal by the conveyor, whereby maintenance of the tilting unit is reduced. The guide linkage, the connecting rod and the tilting unit are all in close vicinity to the sole of the mine gallery to leave a considerable free space between the arrangement and the roof of the mine gallery.« less

Analyses of geological and hydrodynamic controls on methane emissions experienced in a Lower Kittanning coal mine

PubMed Central

Karacan, C. Özgen; Goodman, Gerrit V.R.

2015-01-01

This paper presents a study assessing potential factors and migration paths of methane emissions experienced in a room-and-pillar mine in Lower Kittanning coal, Indiana County, Pennsylvania. Methane emissions were not excessive at idle mining areas, but significant methane was measured during coal mining and loading. Although methane concentrations in the mine did not exceed 1% limit during operation due to the presence of adequate dilution airflow, the source of methane and its migration into the mine was still a concern. In the course of this study, structural and depositional properties of the area were evaluated to assess complexity and sealing capacity of roof rocks. Composition, gas content, and permeability of Lower Kittanning coal, results of flotation tests, and geochemistry of groundwater obtained from observation boreholes were studied to understand the properties of coal and potential effects of old abandoned mines within the same area. These data were combined with the data obtained from exploration boreholes, such as depths, elevations, thicknesses, ash content, and heat value of coal. Univariate statistical and principal component analyses (PCA), as well as geostatistical simulations and co-simulations, were performed on various spatial attributes to reveal interrelationships and to establish area-wide distributions. These studies helped in analyzing groundwater quality and determining gas-in-place (GIP) of the Lower Kittanning seam. Furthermore, groundwater level and head on the Lower Kittanning coal were modeled and flow gradients within the study area were examined. Modeling results were interpreted with the structural geology of the Allegheny Group of formations above the Lower Kittanning coal to understand the potential source of gas and its migration paths. Analyses suggested that the source of methane was likely the overlying seams such as the Middle and Upper Kittanning coals and Freeport seams of the Allegheny Group. Simulated ground-water water elevations, gradients of groundwater flow, and the presence of recharge and discharge locations at very close proximity to the mine indicated that methane likely was carried with groundwater towards the mine entries. Existing fractures within the overlying strata and their orientation due to the geologic conditions of the area, and activation of slickensides between shale and sandstones due to differential compaction during mining, were interpreted as the potential flow paths. PMID:26478644

Reflection spectra of solids of planetary interest

NASA Technical Reports Server (NTRS)

Sill, G. T.

1973-01-01

The spectra of solids are reproduced which might be found on the surfaces of planetary bodies or as solid condensates in the upper planetary atmosphere. Among these are spectra of various iron compounds of interest in the study of the clouds of Venus. Other spectra are included of various sulfides, some at low temperature, relevant to the planet Jupiter. Meteorite and coal abstracts are also included, to illustrate dark carbon compounds.

Reflection spectra of solids of planetary interest

NASA Technical Reports Server (NTRS)

Sill, G. T.; Carm, O.

1973-01-01

This paper reproduces the spectra of solids which might be found on the surfaces of planetary bodies or as solid condensates in the upper planetary atmosphere. Among these are spectra of various iron compounds of interest in the study of the clouds of Venus. Other spectra (some at low temperature) are included for various sulfides relevant to the planet Jupiter. Meteorite and coal spectra are also included to illustrate dark carbon compounds.

Inventory of Neoproterozoic and Paleozoic strata in Sonora, Mexico

USGS Publications Warehouse

Stewart, John H.; Poole, Forrest G.

2002-01-01

This compilation is an inventory of all known outcrops of Neoproterozoic and Paleozoic strata in Sonora, Mexico. We have not attempted an interpretation of the regional stratigraphic or structural setting of the strata. Brief summaries of the stratigraphic setting of the Sonora rocks are given in Poole and Hayes (1971), Rangin (1978), Stewart and others (1984, 1990), and Poole and Madrid (1986; 1988b). More specific information on the setting of strata of specific ages are given by Stewart and others (2002) for the Neoproterozoic and Cambrian; by Poole and others (1995a) for Ordovician shelf strata; by Poole and others (1995b) for Ordovician deep-water openbasin strata; by Poole and others (1997, 1998, 2000a) for Silurian strata; and by Poole and others (2000a) for Mississippian strata. Other reports that discuss regional aspects of Paleozoic stratigraphy include López-Ramos (1982), Peiffer-Rangin, (1979, 1988), Pérez-Ramos (1992), and Stewart and others (1997, 1999a). Structurally, the major Paleozoic feature of Sonora is the Sonora allochthon, consisting of deep-water (eugeoclinal) strata emplaced in the Permian over shelf (miogeoclinal) deposits (Poole and others, 1995a,b; Poole and Perry, 1997; 1998). The emplacement structure is generally considered to be a major Permian continental margin thrust fault that emplaced the deep-water rocks northward over shelf (miogeoclinal) deposits. An alternate interpretation has been presented by Stewart and others (2002). He proposed that the emplacement of the Sonora allochthon was along a major Permian transpressional structure that was primarily a strike-slip fault with only a minor thrust component . The Mojave-Sonora megashear has been proposed to disrupt Neoproterozoic and Paleozoic trends in Sonora. This feature is a hypothetical, left-lateral, northwest-striking fault extending across northern Sonora and the southwestern United States (Silver and Anderson, 1974; Anderson and Schmidt, 1983). It is proposed to have Jurassic displacements of about 700-800 km. Current opinion is mixed concerning whether the Mojave-Sonora megashear exists (see discussions and references in Stewart and others, 1990; 1999a). The inventory presented here is the product of a search of the literature for described Neoproterozoic and Paleozoic localities and our examination of a large number of the outcrops in the field. The individual localities are described by reference letters and numbers, locality name, latitude and longitude, a brief text on the stratigraphy of the strata, and references. Figure 1 is an index showing the location of Sonora and the location of figure 2. The location of a few localites that are outside of figure 2 are also shown on figure 1. We also include a separate description of localities that have been erroneously reported, on the based of our field examinations, to contain Neoproterozoic and Paleozoic rocks. We include a brief description of problematic strata in southern Sonora that have been described as Paleozoic, but may be at least in part Mesozoic. Figures 3-11 show the distribution of Neoproterozoic, Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, and Permian strata in Sonora.

Work conditions and morbidity among coal miners in Guachetá, Colombia: The miners' perspective.

PubMed

Jiménez-Forero, Claudia P; Zabala, Ivonne T; Idrovo, Álvaro J

2015-08-01

Investigations in Colombia about work and health conditions in coal mining are scarce and few have focused on the perception of the exposed population and their behaviors in response to inherent risks. To determine the association between work conditions and the perception of morbidity among coal miners in Guachetá, Cundinamarca. A cross-sectional study was performed with 154 workers selected randomly from the total registered with the municipality. Information about social and demographic characteristics and work and health conditions in the mines was gathered. The prevalence was estimated for respiratory, musculoskeletal and auditory disorders. The associations between certain work conditions, and events with a prevalence over 30% were explored using bivariate and multivariate analyses with Poisson regressions with robust variance. Workers were mostly men. Ages ranged from 18 to 77 years. Most frequently reported health problems were: back pain (46.1 %), pain in an upper limb (40.3%), pain in a lower limb (34.4 %), and respiratory (17.5 %) and auditory problems (13.6 %). Significant differences in perception were found depending on time on the job and underground or ground work conditions. The most recognized risks were those associated with musculoskeletal disorders since they were closer in time to the work performed (time discount). Some actions to identify psychological traits are proposed in order to improve risk perception among coal miners.

Persistent and widespread occurrence of bioactive quinone pigments during post-Paleozoic crinoid diversification

PubMed Central

Wolkenstein, Klaus

2015-01-01

Secondary metabolites often play an important role in the adaptation of organisms to their environment. However, little is known about the secondary metabolites of ancient organisms and their evolutionary history. Chemical analysis of exceptionally well-preserved colored fossil crinoids and modern crinoids from the deep sea suggests that bioactive polycyclic quinones related to hypericin were, and still are, globally widespread in post-Paleozoic crinoids. The discovery of hypericinoid pigments both in fossil and in present-day representatives of the order Isocrinida indicates that the pigments remained almost unchanged since the Mesozoic, also suggesting that the original color of hypericinoid-containing ancient crinoids may have been analogous to that of their modern relatives. The persistent and widespread occurrence, spatially as well as taxonomically, of hypericinoid pigments in various orders during the adaptive radiation of post-Paleozoic crinoids suggests a general functional importance of the pigments, contributing to the evolutionary success of the Crinoidea. PMID:25730856

Depositional systems and stratigraphy of Paleozoic and Lower Mesozoic rocks in outcrop, Tassili region, southwest Algeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hertig, S.P.; Tye, R.S.; Coffield, D.Q.

1991-08-01

Paleozoic to Lower Mesozoic strata of the southeastern Algerian Tassili are traditionally subdivided by regionally extensive unconformities such as the Pan African, Taconic, Caledonian, and Hercynian. Using outcrop data from southeastern Algeria, this classic approach is modified by reinterpreting the genesis of these unconformities and rock sequences. Five prominent sequences, defined within the Paleozoic and lower Mesozoic section, usually consist of a succession of lowstand, transgressive, and highstand system tracts separated by sequence boundaries or transgressive surfaces. The Pan-African, Taconic, Caledonian, and Hercynian unconformities are sequence boundaries. Important sequence boundaries also occur within the Ordovician and Silurian sections. These sequencesmore » correlate with subsurface data in the Illizi basin and provide a framework for renewed exploration in the subsurface of the Algerian Sahara, where more than 30 billion bbl of recoverable oil and oil equivalent have been generated and trapped.« less

A paired apatite and calcite clumped isotope thermometry approach to estimating Cambro-Ordovician seawater temperatures and isotopic composition

NASA Astrophysics Data System (ADS)

Bergmann, Kristin D.; Finnegan, Seth; Creel, Roger; Eiler, John M.; Hughes, Nigel C.; Popov, Leonid E.; Fischer, Woodward W.

2018-03-01

The secular increase in δ18O values of both calcitic and phosphatic marine fossils through early Phanerozoic time suggests either that (1) early Paleozoic surface temperatures were high, in excess of 40 °C (tropical MAT), (2) the δ18O value of seawater has increased by 7-8‰ VSMOW through Paleozoic time, or (3) diagenesis has altered secular trends in early Paleozoic samples. Carbonate clumped isotope analysis, in combination with petrographic and elemental analysis, can deconvolve fluid composition from temperature effects and therefore determine which of these hypotheses best explain the secular δ18O increase. Clumped isotope measurements of a suite of calcitic and phosphatic marine fossils from late Cambrian- to Middle-late Ordovician-aged strata-the first paired fossil study of its kind-document tropical sea surface temperatures near modern temperatures (26-38 °C) and seawater oxygen isotope ratios similar to today's ratios.

The Chara-Sina dyke swarm in the structure of the Middle Paleozoic Vilyui rift system (Siberian Craton)

NASA Astrophysics Data System (ADS)

Kiselev, A. I.; Konstantinov, K. M.; Yarmolyuk, V. V.; Ivanov, A. V.

2016-11-01

The formation of the Vilyui rift system in the eastern Siberian Craton was finished with breakdown of the continent and formation of its eastern margin. A characteristic feature of this rift system is the radial distribution of dyke swarms of basic rocks. This peculiarity allows us to relate it to the breaking processes above the mantle plume, the center of which was located in the region overlain in the modern structure by the foreland of the Verkhoyan folded-thrust belt. The Chara-Sina dyke swarm is the southern part of a large area of Middle Paleozoic basaltic magmatism in the eastern Siberian Craton. The OIB-like geochemical characteristics of dolerite allow us to suggest that the melting substrate for Middle Paleozoic basaltic magmatism was represented by a relatively homogeneous, mid-depleted mantle of the plume with geochemical parameters similar to those of OIB.