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1

Mount St. Augustine volcano fumarole wall rock alteration: mineralogy, zoning, composition and numerical models of its formation process  

NASA Astrophysics Data System (ADS)

Intensely altered wall rock was collected from high-temperature (640 °C) and low-temperature (375 °C) vents at Augustine volcano in July 1989. The high-temperature altered rock exhibits distinct mineral zoning differentiated by color bands. In order of decreasing temperature, the color bands and their mineral assemblages are: (a) white to grey (tridymite-anhydrite); (b) pink to red (tridymite-hematite-Fe hydroxide-molysite (FeCl 3) with minor amounts of anhydrite and halite); and (c) dark green to green (anhydrite-halite-sylvite-tridymite with minor amounts of molysite, soda and potash alum, and other sodium and potassium sulfates). The alteration products around the low-temperature vents are dominantly cristobalite and amorphous silica with minor potash and soda alum, aphthitalite, alunogen and anhydrite. Compared to fresh 1986 Augustine lava, the altered rocks exhibit enrichments in silica, base metals, halogens and sulfur and show very strong depletions in Al in all alteration zones and in iron, alkali and alkaline earth elements in some of the alteration zones. To help understand the origins of the mineral assemblages in altered Augustine rocks, we applied the thermochemical modeling program, GASWORKS, in calculations of: (a) reaction of the 1987 and 1989 gases with wall rock at 640 and 375 °C; (b) cooling of the 1987 gas from 870 to 100 °C with and without mineral fractionation; (c) cooling of the 1989 gas from 757 to 100 °C with and without mineral fractionation; and (d) mixing of the 1987 and 1989 gases with air. The 640 °C gas-rock reaction produces an assemblage consisting of silicates (tridymite, albite, diopside, sanidine and andalusite), oxides (magnetite and hercynite) and sulfides (bornite, chalcocite, molybdenite and sphalerite). The 375 °C gas-rock reaction produces dominantly silicates (quartz, albite, andalusite, microcline, cordierite, anorthite and tremolite) and subordinate amounts of sulfides (pyrite, chalcocite and wurtzite), oxides (magnetite), sulfates (anhydrite) and halides (halite). The cooling calculations produce: (a) anhydrite, halite, sylvite; (b) Cu, Mo, Fe and Zn sulfides; (c) Mg fluoride at high temperature (> 370 °C); (d) chlorides, fluorides and sulfates of Mn, Fe, Zn, Cu and Al at intermediate temperature (170-370 °C); and (e) hydrated sulfates, liquid sulfur, crystalline sulfur, hydrated sulfuric acid and water at low temperature

Getahun, Aberra; Reed, Mark H.; Symonds, Robert

1996-05-01

2

Mount St. Augustine volcano fumarole wall rock alteration: Mineralogy, zoning, composition and numerical models of its formation process  

USGS Publications Warehouse

Intensely altered wall rock was collected from high-temperature (640??C) and low-temperature (375??C) vents at Augustine volcano in July 1989. The high-temperature altered rock exhibits distinct mineral zoning differentiated by color bands. In order of decreasing temperature, the color bands and their mineral assemblages are: (a) white to grey (tridymite-anhydrite); (b) pink to red (tridymite-hematite-Fe hydroxide-molysite (FeCl3) with minor amounts of anhydrite and halite); and (c) dark green to green (anhydrite-halite-sylvite-tridymite with minor amounts of molysite, soda and potash alum, and other sodium and potassium sulfates). The alteration products around the low-temperature vents are dominantly cristobalite and amorphous silica with minor potash and soda alum, aphthitalite, alunogen and anhydrite. Compared to fresh 1986 Augustine lava, the altered rocks exhibit enrichments in silica, base metals, halogens and sulfur and show very strong depletions in Al in all alteration zones and in iron, alkali and alkaline earth elements in some of the alteration zones. To help understand the origins of the mineral assemblages in altered Augustine rocks, we applied the thermochemical modeling program, GASWORKS, in calculations of: (a) reaction of the 1987 and 1989 gases with wall rock at 640 and 375??C; (b) cooling of the 1987 gas from 870 to 100??C with and without mineral fractionation; (c) cooling of the 1989 gas from 757 to 100??C with and without mineral fractionation; and (d) mixing of the 1987 and 1989 gases with air. The 640??C gas-rock reaction produces an assemblage consisting of silicates (tridymite, albite, diopside, sanidine and andalusite), oxides (magnetite and hercynite) and sulfides (bornite, chalcocite, molybdenite and sphalerite). The 375??C gas-rock reaction produces dominantly silicates (quartz, albite, andalusite, microcline, cordierite, anorthite and tremolite) and subordinate amounts of sulfides (pyrite, chalcocite and wurtzite), oxides (magnetite), sulfates (anhydrite) and halides (halite). The cooling calculations produce: (a) anhydrite, halite, sylvite; (b) Cu, Mo, Fe and Zn sulfides; (c) Mg fluoride at high temperature (> 370??C); (d) chlorides, fluorides and sulfates of Mn, Fe, Zn, Cu and Al at intermediate temperature (170-370??C); and (e) hydrated sulfates, liquid sulfur, crystalline sulfur, hydrated sulfuric acid and water at low temperature ( 0.41 (> 628??C). This is followed by precipitation of sulfates of Fe, Cu, Pb, Zn and Al at lg/a ratios between 0.41 and -0.4 (628-178??C). At a lg/r ratio of < - 0.4 (178??C), anhydrous sulfates are replaced by their hydrated forms and hygroscopic sulfuric acid forms. At these low g/a ratios, hydrated sulfuric acid becomes the dominant phase in the system. Comparison of the thermochemical modeling results with the natural samples suggests that the alteration assemblages include: (1) minerals that precipitate from direct cooling of the volcanic gas; (2) phases that form by volcanic gases mixing with air; and (3) phases that form by volcanic gas-air-rock reaction. A complex interplay of the three processes produces the observed mineral zoning. Another implication of the numerical simulation results is that most of the observed incrustation and sublimate minerals apparently formed below 700??C.

Getahun, A.; Reed, M.H.; Symonds, R.

1996-01-01

3

Textures, paragenesis and wall-rock alteration of lode-gold deposits in the Charters Towers district, north Queensland: implications for the conditions of ore formation  

NASA Astrophysics Data System (ADS)

Ore deposits of the Charters Towers Goldfield (CTGF) are mainly hosted by fault-fill veins. Extensional (˜8% of all veins) and stockwork-like (˜3%) veins are less common and of little economic significance. Crosscutting relationships and published structural and geochronological data indicate a Late Silurian to Early Devonian timing of gold mineralization, coincident with regional shortening (D4) and I-type magmatism. Paragenetic relationships, which are uniform in veins everywhere within the CTGF, suggest that vein formation commenced with the deposition of large volumes of buck quartz (stage I), followed by buck and comb quartz, and significant pyrite and arsenopyrite precipitation (stage II). Gold was introduced during stage III, after earlier sphalerite and coincident with galena and chalcopyrite. Narrow, discontinuous calcite veins of stage IV mark the waning of gold-related hydrothermal activity or a later unrelated episode. Ore zones within the veins are everywhere composed of comb and/or gray quartz, calcite and/or ankerite and bands or clusters of fractured pyrite that are spatially associated with galena, sphalerite or chalcopyrite. Low-grade or barren vein sections, on the other hand, are mainly composed of milky buck quartz with little evidence for modification, overprinting or interaction with later fluids. Gold-related hydrothermal wall-rock alteration is symmetrically zoned, displaying proximal sericite-ankerite and distal epidote-chlorite-hematite assemblages that may be taken to imply wall-rock interaction with near neutral fluids (pH 5-6). Isocon plots assuming immobile Al, P, Ti, Y and Zr consistently indicate As, K, Pb, S and Zn enrichment and Na, Si and Sr depletion in altered wall-rock specimens relative to the least altered rocks. Alteration assemblages, quartz textures, fault rocks and published fluid inclusion and stable isotope data imply that the veins were formed under conditions of episodic fluid overpressuring (˜0.9-3.8 kbar), at a depth of ˜7 km and a temperature of ˜310°C. The published fluid inclusion data also imply that gold precipitation may have been brought about by fluid mixing. However, physi- and chemisorption of gold complexes onto sulfide surfaces may have been important depositional processes and controls on gold enrichment at the millimeter to centimeter scale, given that most gold particles are attached to the surfaces of pyrite crystals of stage II or to etch-pits and fracture surfaces within the earlier pyrite.

Kreuzer, Oliver P.

2006-01-01

4

Wall rock alteration, Atud gold mine, Eastern Desert, Egypt: processes and P?T?X CO 2 conditions of metasomatism  

Microsoft Academic Search

The Atud gold mine, central Eastern Desert of Egypt, is located in an intrusive metagabbro-diorite complex that abutts the conglomerate-greywacke-slate series of the Pan-African Belt in Egypt. Gold-bearing quartz veins occur as fracture filling in the Neoproterozoic dioritic rocks and along their contacts with the metagabbro. Gold mineralisation is associated with discrete metasomatic alteration zones around shear zones and quartz-carbonate

Hassan Z. Harraz

1999-01-01

5

Geology and wall rock alteration at the Hercynian Draa Sfar Zn PbCu massive sulphide deposit, Morocco  

E-print Network

deposits, and lesser dykes of aphanitic basalt and gabbro. Thin- to thick-bedded, black carbonaceous argillite, minor intercalated siltstone, and a large gabbro sill dominate the hanging wall lithofacies

Paris-Sud XI, Université de

6

Heat-model analysis of wall rocks below a diabase sill in Huimin Sag, China compared with thermal alteration of mudstone to carbargilite and hornfels and with increase of vitrinite reflectance  

Microsoft Academic Search

This paper presents an application of heat flow modeling in a study on the thermal alteration of the underlying sedimentary rocks caused by an isolated intrusive sill in Huimin Sag, Bohai Bay Basin, China. It is found that during the cooling of the sill, the assignment of the heat transferred into its both sides can be acquired according to the

Dayong Wang; Xiancai Lu; Xuejun Zhang; Shijin Xu; Wenxuan Hu; Liangshu Wang

2007-01-01

7

A mechanism for high wall-rock velocities in rockbursts  

USGS Publications Warehouse

Considerable evidence has been reported for wall-rock velocities during rockbursts in deep gold mines that are substantially greater than ground velocities associated with the primary seismic events. Whereas varied evidence suggests that slip across a fault at the source of an event generates nearby particle velocities of, at most, several m/s, numerous observations, in nearby damaged tunnels, for instance, imply wall-rock velocities of the order of 10 m/s and greater. The common observation of slab buckling or breakouts in the sidewalls of damaged excavations suggests that slab flexure may be the mechanism for causing high rock ejection velocities. Following its formation, a sidewall slab buckles, causing the flexure to increase until the stress generated by flexure reaches the limit 5 that can be supported by the sidewall rock. I assume here that S is the uniaxial compressive strength. Once the flexural stress exceeds S, presumably due to the additional load imposed by a nearby seismic event, the slab fractures and unflexes violently. The peak wall-rock velocity v thereby generated is given by v=(3 + 1-??2/2)1 2 S/?????E for rock of density ??, Young's modulus E, and Poisson's ratio ??. Typical values of these rock properties for the deep gold mines of South Africa yield v= 26 m/s and for especially strong quartzites encountered in these same mines, v> 50m/s. Even though this slab buckling process leads to remarkably high ejection velocities and violent damage in excavations, the energy released during this failure is only a tiny fraction of that released in the primary seismic event, typically of magnitude 2 or greater.

McGarr, A.

1997-01-01

8

Kimberlite Wall Rock Fragmentation: Venetia K08 Pipe Development  

NASA Astrophysics Data System (ADS)

Volcanic systems impose powerful disrupting forces on the country rock into which they intrude. The nature of the induced brittle deformation or fragmentation can be characteristic of the volcanic processes ongoing within the volcanic system, but are most typically partially removed or obscured by repeated, overprinting volcanic activity in mature pipes. Incompletely evolved pipes may therefore provide important evidence for the types and stages of wall rock fragmentation, and mechanical processes responsible for the fragmentation. Evidence for preserved stages of fragmentation is presented from a detailed study of the K08 pipe within the Cambrian Venetia kimberlite cluster, South Africa. This paper investigates the growth history of the K08 pipe and the mechanics of pipe development based on observations in the pit, drill core and thin sections, from geochemical analyses, particle size distribution analyses, and 3D modeling. Present open pit exposures of the K08 pipe comprise greater than 90% mega-breccia of country rock clasts (gneiss and schist) with <10% intruding, coherent kimberlite. Drill core shows that below about 225 m the CRB includes increasing quantities of kimberlite. The breccia clasts are angular, clast-supported with void or carbonate cement between the clasts. Average clast sizes define sub-horizontal layers tens of metres thick across the pipe. Structural and textural observations indicate the presence of zones of re-fragmentation or zones of brittle shearing. Breccia textural studies and fractal statistics on particle size distributions (PSD) is used to quantify sheared and non- sheared breccia zones. The calculated energy required to form the non-sheared breccia PSD implies an explosive early stage of fragmentation that pre-conditions the rock mass. The pre-conditioning would have been caused by explosions that are either phreatic or phreatomagmatic in nature. The explosions are likely to have been centered on a dyke, or pulses of preceding volatile-fluid phases, which have encountered a local hydrologically active fault. The explosions were inadequate in mechanical energy release (72% of a mine production blast) to eject material from the pipe, and the pipe may not have breached surface. The next stage of fragmentation is interpreted to have been an upward-moving collapse of the pre-conditioned hanging wall of a subterranean volcanic excavation. This would explain the mega-scale layering across the width of the breccia pipe. It must be questioned whether the preserved K08 architecture represents early pipe development in general, or is a special case of a late pipe geometry modification process. Previous literature describes sidewall and hanging wall caving processes elsewhere in the Venetia cluster and other kimberlites world wide. A requirement for emplacement models that include upward pipe growth processes is the availability of space (mass deficit at depth) into which the caving and/or dilating breccia can expand. It is possible that K08 might be connected to adjacent K02 at a depth somewhere below 400m, which would explain the presence of volcaniclastic kimberlite at depth within the K08 pipe. K08 is likely an incomplete ancillary sideward development to K02. The latest stage of brecciation is quantified through an observed evolution in the fractal dimension of the PSD. It is interpreted to be due to complex adjustments in volume in the pipe causing shearing and re-fragmentation of the breccia.

Barnett, W.; Kurszlaukis, S.; Tait, M.; Dirks, P.

2009-05-01

9

Interaction of magma with sedimentary wall rock and magnetite ore genesis in the Panzhihua mafic  

E-print Network

1 Interaction of magma with sedimentary wall rock and magnetite ore genesis in the Panzhihua mafic of large quantities of CO2 as the rocks were converted to marble and skarns during intrusion and close to the liquidus. We propose that CO2-rich fluids released during decarbonatization of sedimentary

Paris-Sud XI, Université de

10

On Two-Phase Relative Permeability and Capillary Pressure ofRough-Walled Rock Fractures  

Microsoft Academic Search

This paper presents a conceptual and numerical model of multiphase flow in fractures. The void space of real rough-walled rock fractures is conceptualized as a two-dimensional heterogeneous porous medium, characterized by aperture as a function of position in the fracture plane. Portions of a fracture are occupied by wetting and nonwetting phase, respectively, according to local capillary pressure and accessibility

K. Pruess; Y. W. Tsang

1989-01-01

11

On two-phase relative permeability and capillary pressure of rough-walled rock fractures  

Microsoft Academic Search

This paper presents a conceptual and numerical model of multiphase flow in fractures. The void space of real rough-walled rock fractures is conceptualized as a two-dimensional heterogeneous porous medium, characterized by aperture as a function of position in the fracture plane. Portions of a fracture are occupied by wetting and nonwetting phase, respectively, according to local capillary pressure and global

K. Pruess; Y. W. Tsang

1990-01-01

12

On Two-Phase Relative Permeability and Capillary Pressure of Rough-Walled Rock Fractures  

Microsoft Academic Search

This paper presents a conceptual and numerical model of multiphase flow in fractures. The void space of real rough-walled rock fractures is conceptualized as a two-dimensional heterogeneous porous medium, characterized by aperture as a function of position in the fracture plane. Portions of a fracture are occupied by wetting and nonwetting phase, respectively, according to local capillary pressure and global

K. Pruess; Y. W. Tsang

1990-01-01

13

Emplacement of multiple magma sheets and wall rock deformation: Trachyte Mesa intrusion, Henry Mountains, Utah  

Microsoft Academic Search

A detailed structural and rock magnetic study of the Trachyte Mesa intrusion and deformed sedimentary wall rocks, Henry Mountains, Utah, indicates that the intrusion grew vertically and horizontally by the accumulation of multiple horizontal magma sheets. 2–3cm thick shear zones recognized by intensely cataclasized plagioclase phenocrysts define the contact between sheets. Sheets have bulbous and \\/ or steep frontal terminations

Sven Morgan; Amy Stanik; Eric Horsman; Basil Tikoff; Michel de Saint Blanquat; Guillaume Habert

2008-01-01

14

Large-Scale In-situ Experiments to Determine Geochemical Alterations and Microbial Activities at the Geological Repository  

NASA Astrophysics Data System (ADS)

The countries that have generated nuclear power have facing problems on the disposal of accumulated radioactive wastes. Geological disposal method has been chosen in many countries including Korea. A safety issue after the closure of geological repository has been raised, because microbial activities lead overpressure in the underground facilities through gas production. In particular, biodegradable organic materials derived from low- and intermediate-level radioactive wastes play important role on microbial activities in the geological repository. This study performed large scale in-situ experiments using organic wastes and groundwater, and investigated geochemical alteration and microbial activities at early stage (~63 days) as representative of the period, after closure of the geological repository. The geochemical alteration controlled significantly the microorganism types and populations. Database of the biogeochemical alteration facilitates prediction of radionuclides' mobility and establishment of remedial strategy against unpredictable accidents and hazards at early stage right after closure of the geological repository.

Choung, S.; Francis, A. J.; Um, W.; Choi, S.; Kim, S.; Park, J.; Kim, S.

2013-12-01

15

Geology  

SciTech Connect

This chapter summarizes the geology of the single-shell tank (SST) farms in the context of the region’s geologic history. This chapter is based on the information in the geology data package for the SST waste management areas and SST RFI Appendix E, which builds upon previous reports on the tank farm geology and Integrated Disposal Facility geology with information available after those reports were published.

Reidel, Stephen P.

2008-01-17

16

Geology and porphyry copper-type alteration-mineralization of igneous rocks at the Christmas Mine, Gila County, Arizona  

USGS Publications Warehouse

The Christmas copper deposit, located in southern Gila County, Arizona, is part of the major porphyry copper province of southwestern North America. Although Christmas is known for skarn deposits in Paleozoic carbonate rocks, ore-grade porphyry-type copper mineralization also occurs in a composite granodioritic intrusive complex and adjacent mafic volcanic country rocks. This study considers the nature, distribution, and genesis of alteration-mineralization in the igneous rock environment at Christmas. At the southeast end of the Dripping Spring Mountains, the Pennsylvanian Naco Limestone is unconformably overlain by the Cretaceous Williamson Canyon Volcanics, a westward-thinning sequence of basaltic volcanic breccia and lava flows, and subordinate clastic sedimentary rocks. Paleozoic and Mesozoic strata are intruded by Laramide-age dikes, sills, and small stocks of hornblende andesite porphyry and hornblende rhyodacite porphyry, and the mineralized Christmas intrusive complex. Rocks of the elongate Christmas stock, intruded along an east-northeast-trending fracture zone, are grouped into early, veined quartz diorite (Dark Phase), biotite granodiorite porphyry (Light Phase), and granodiorite; and late, unveined dacite porphyry and granodiorite porphyry. Biotite rhyodacite porphyry dikes extending east and west from the vicinity of the stock are probably coeval with biotite granodiorite porphyry. Accumulated normal displacement of approximately 1 km along the northwest-trending Christmas-Joker fault system has juxtaposed contrasting levels (lower, intrusive-carbonate rock environment and upper, intrusive-volcanic rock environment) within the porphyry copper system. K-Ar age determinations and whole-rock chemical analyses of the major intrusive rock types indicate that Laramide calc-alkaline magmatism and ore deposition at Christmas evolved over an extended period from within the Late Cretaceous (~75-80 m.y. ago) to early Paleocene (~63-61 m.y. ago). The sequence of igneous rocks is progressively more alkaline and silicic from basalt to granodiorite. Early (Stage I) chalcopyrite-bornite (-molybdenite) mineralization and genetically related K-silicate alteration are centered on the Christmas stock. K-silicate alteration is manifested by pervasive hornblende-destructive biotitization in the stock, biotitization of basaltic volcanic wall rocks, and a continuous stockwork of K-feldspar veinlets and quartz-K-feldspar veins in the stock and quartz-sulfide veins in volcanic rocks. Younger (Stage II) pyrite-chalcopyrite mineralization and quartz-sericite-chlorite alteration occur in a zone overlapping with but largely peripheral to the zone of Stage I stockwork veins. Within the Christmas intrusive complex, K-silicate-altered rocks in the central stock are flanked east and west by zones of fracture-controlled quartz-sericite alteration and strong pyritization. In volcanic rocks quartz-chlorite-pyrite-chalcopyrite veins are superimposed on earlier biotitization and crosscut Stage I quartz-sulfide veins. Beyond the zones of quartz-sericite alteration, biotite rhyodacite porphyry dikes contain the propylitic alteration assemblage epidote-chlorite-albite-sphene. Chemical analyses indicate the following changes during pervasive alteration of igneous rocks: (1) addition of Si, K, H, S, and Cu, and loss of Fe 3+ and Ca during intense biotitization of basalt; (2) loss of Na and Ca, increase of Fe3+/Fe2+, and strong H-metasomatism during sericitization of quartz diorite; and (3) increase in Ca, Na, and Fe3+/Fe2+, and loss of K during intense propylitization of biotite rhyodacite porphyry dikes. Thorough biotitization of biotite granodiorite porphyry in the Christmas stock was largely an isochemical process. Fluid-inclusion petrography reveals that Stage I veins are characterized by low to moderate populations of moderate-salinity and gas-rich inclusions, and sparse but ubiquitous halite-bearing inclusions. Moderate-salinity an

Koski, Randolph A.

1979-01-01

17

Origin of saline, neutral-pH, reduced epithermal waters by reaction of acidic magmatic gas condensates with wall rock  

SciTech Connect

Fluid inclusions in quartz and sphalerite of epithermal veins containing galena, sphalerite and chalcopyrite with silver sulfides and electrum commonly have salinities of 2 to 10 weight percent NaCl equivalent. Examples include Bohemia, OR, Comstock, NV, and Creede, CO. Salinities in such base metal-rich systems are apparently greater than those in gold-adularia, base metal-poor systems such as Sleeper, NV, Republic, WA, and Hishikare, Kyushu. Saline epithermal fluids are commonly assumed to have been derived from saline magmatic brines, from local host formations, as has been suggested for Creede, or from evaporative concentration (boiling) of more dilute meteoric ground water. Another possibility, which may be the most common origin, is reaction of wall rocks with magmatic gas condensates rich in HCl and sulfuric acid. A mixture of one part Augustine Volcanic gas condensate in 10 parts cold ground water has a pH of 0.7 and the dominant cation is H[sup +] by a factor of 10[sup 4]. Calculated reaction of this condensate mixture with andesite at 300 C to a water/rock ratio (w/r) of 4.6 yields an NaCl-dominated fluid with a total salinity of 2.1 wt %. and pH 3.7. Further reaction, to w/r 0.14 yields a fluid salinity of 2.6 wt % and pH of 5.7; this fluid is in equilibrium with a propylitic alteration assemblage. Aqueous sulfide accumulates during the rock reaction as sulfate is reduced to sulfide when ferrous iron is oxidized to ferric iron. Sulfide concentration in the latter fluid is 32 ppm, far exceeding sulfate concentration. In the overall reaction, hydrogen ion is exchanged for base cations (including base metals) and sulfate is reduced to sulfide.

Reed, M.H. (Univ. of Oregon, Eugene, OR (United States). Dept. of Geological Sciences)

1993-04-01

18

Fe(III)-montmorillonite: Basic properties and diffusion of tracers relevant to alteration of bentonite in deep geological disposal  

Microsoft Academic Search

In the deep geological repository of high-level nuclear waste (HLW), the interaction of carbon steel (Fe) overpack container and the back-fill clay mineral, montmorillonite (mont), is an important issue to be clarified in view of the long-term performance of clay mineral as an engineered barrier. To arrive at some understanding of the altered clay at the Fe\\/clay interface, Fe(III)-mont is

Jayappa Manjanna; Tamotsu Kozaki; Seichi Sato

2009-01-01

19

Alteration of oceanic crust and geologic cycling of chlorine and water  

Microsoft Academic Search

We report new estimates of transport rates for H 2 O and Cl between the mantle and surface reservoirs. Our estimates take into consideration alteration of oceanic crust, especially that of plutonic rocks, and possible subduction of sediments. The effect of (hydrothermal) alteration on the Cl budget seems to be negligible, but the effect on the H 2 O budget

Emi Ito; David M. Harris; Alfred T. Anderson Jr.

1983-01-01

20

Geology  

NSDL National Science Digital Library

With three levels to choose from on each page - beginner, intermediate or advanced - this site provides information on the many different kinds of geological exploration. The elements that make up minerals and the different ways minerals are developed, The special characteristics of minerals, like physical properties, is explained. Earths tectonic plates, the reasons they move, and the effects of the shifting are also given. Also featured is fossils and how they are developed and are found, as well as why fossils are useful tools for scientists.

Jennifer Bergman

2009-08-03

21

The fossil hydrothermal system of Saint Martin, Lesser Antilles: geology and lateral distribution of alterations  

NASA Astrophysics Data System (ADS)

The fossil geothermal system of Saint Martin, Lesser Antilles, was generated by an intrusion of quartz-diorite of Oligocene age into Eocene volcano-sedimentary host rocks. Adjacent to the pluton, the alteration pattern crops out continuously in the Fort Hill-Kool Bay area over a distance of 4 km. The lithology of the altered host rocks is the following: (1) alternating marls, limestones and minor hyaloclastite (Lower Eocene); (2) hyaloclastite and andesitic lava flows (Middle Eocene); (3) regularly bedded fine-grained hyaloclastite (Upper Eocene). On the basis of alteration petrography, chemistry and fluid-inclusion study, three alteration events have been distinguished: (1) High-temperature event (510 > T > 350°C) accompanied by fluids with salinity higher than 35 wt.% NaCl-eq), mainly represented by tourmaline, quartz, magnetite, orthoclase, apatite and sulfide veins, occurring at the periphery of the pluton and along distal regional faults. (2) Moderate temperature event occurring as veins and pervasive alteration. Veins containing quartz, phengite, pyrite and minor dickite or chlorite ( T = 300°C, very low salinity) are superimposed on the early high-temperature veins. Pervasive alteration affected large concentric zones: the inner zone (3 km width) shows an assemblage of epidote, quartz, actinolite ± magnetite at the periphery of the pluton and epidote, quartz and chlorite farther away. The outer zone (1 km width) shows calcite and mixed-layer illite/smectite (I/S) with ordering type R3 and chlorite/smectite (C/S). Fluid inclusions indicate that salinity and temperature decrease outward from the intrusion during the moderate-temperature pervasive alteration event (respectively from 320 to 140°C and from 30 to 5 wt.% NaCl-eq). (3) Low-temperature event ( T < 50°C) showing calcite, mixed-layer I/S (RO), chalcedonite or baryte in late disseminated veins. This lateral distribution of alteration is very similar to alteration zoning observed in porphyry ore environment or in active deep geothermal systems as Baca (Valles caldera). It shows contrast between zones of fracture permeability which controlled active flow in the system and large zones where pervasive alteration occurred in an inactive flow regime and can be included with metamorphic process. Phyllic alteration seems a good indicator of the active flow paths in the system of Saint Martin. The alteration pattern in Saint Martin is considered to represent the roots of a deep geothermal system (porphyry ore system?) of Oligocene age, actually eroded.

Beaufort, D.; Westercamp, D.; Legendre, O.; Meunier, A.

1990-04-01

22

Fracturing and hydrothermal alteration in normal fault zones  

Microsoft Academic Search

Large normal fault zones are characterized by intense fracturing and hydrothermal alteration. Displacement is localized in a slip zone of cataclasite, breccia and phyllonite surrounding corrugated and striated fault surfaces. Slip zone rock grades into fractured, but less comminuted and hydrothermally altered rock in the transition zone, which in turn grades abruptly into the wall rock. Fracturing and fluid flow

Ronald L. Bruhn; William T. Parry; William A. Yonkee; Troy Thompson

1994-01-01

23

Forceful emplacement of the Eureka Valley-Joshua Flat-Beer Creek composite pluton into a structural basin in eastern California; internal structure and wall rock deformation  

NASA Astrophysics Data System (ADS)

Anisotropy of Magnetic Susceptibility parameters have been analyzed at 311 locations in the Eureka Valley-Joshua Flat-Beer Creek (EJB) pluton of eastern California. The large amount of data has allowed for the AMS parameters to be contoured using techniques that both reveal map-scale trends and emphasize small-scale differences. The contour maps suggest that magnetic susceptibility is dominantly controlled by composition of the magma but may also be affected by emplacement-related strain as the magma chamber inflated and forced the wall rocks outward. Pluton construction involved two major pulses of different composition magmas that were emplaced sequentially but with overlapping periods of crystallization. The magmas initially intruded as sill-like bodies into a structural basin. The magnetic foliation of the pluton cuts across internal magmatic contacts on the map scale and is parallel to local contacts between the pluton and surrounding metasedimentary wall rocks. The magnetic fabric is similar in orientation and symmetry to intense flattening strains recorded in the aureole rocks. The metasedimentary wall rocks have been shortened between 60 and 70% and this strain magnitude is approximately equal on the west, south, and east margins of the pluton. Strain in the wall rocks is dominantly flattening and concentrated into a narrow (1 km wide) inner aureole. Mapping of bedding/cleavage intersection lineations south of the pluton indicates that the magma made room for itself by translating the wall rocks outward and rotating the already inward dipping wall rocks of the structural basin to sub-vertical. Stretching of the inner aureole around an expanding magma chamber was responsible for the intense shortening. Limited data on the Marble Canyon pluton to the south of the EJB pluton indicates a very similar emplacement process.

Morgan, Sven; Law, Richard; de Saint Blanquat, Michel

2013-11-01

24

The geochemical evolution of clinopyroxene in the Roman Province: A window on decarbonation from wall-rocks to magma  

NASA Astrophysics Data System (ADS)

We present results from magma-carbonate interaction experiments designed to shed light on the geochemical evolution of clinopyroxene in the Roman Province (central Italy). Atmospheric pressure experiments were performed at 1140, 1160 and 1180 °C under NNO, MH and air oxygen buffering conditions. The starting materials were a shoshonite and a phonotephrite doped with different amounts of CaO and CaO + MgO whose stoichiometric proportions reproduced the assimilation by magmas of calcite and dolomite, respectively. The results show that clinopyroxenes, spinels and residual glasses are ubiquitous phases in all run-products. Calcite-doped runs crystallize more clinopyroxene than dolomite-doped runs at the same conditions. This leads to the formation of strong desilicated CaO-rich melts showing compositions comparable to those of magmatic skarns. During magma-carbonate interaction, the content of Fe3 + in clinopyroxene increases with increasing fO2 promoting the substitution of Al for Si in tetrahedral site. Local charge imbalances are also compensated by the incorporation of highly charged cations, such as Ti, into the crystal lattice. According to this cation substitution, Al-Ca-Fe3 +-Ti-rich clinopyroxenes of the skarn environment testify to continuous CO2 fluxes produced by the thermal decomposition of carbonate wall-rocks. Nevertheless, the oxidative capacity of CO2 progressively decreases from the skarn shells towards the interior of the magma chamber driving the crystallization of Si-Fe2 +-Mg-rich clinopyroxenes.

Mollo, S.; Vona, A.

2014-04-01

25

Two-phase flow visualization and relative permeability measurement in transparent replicas of rough-walled rock fractures  

SciTech Connect

Understanding and quantifying multi-phase flow in fractures is important for mathematical and numerical simulation of geothermal reservoirs, nuclear waste repositories, and petroleum reservoirs. While the cubic law for single-phase flow has been well established for parallel-plate fractures theoretically and experimentally, no reliable measurements of multi-phase flow in fractures have been reported. This work reports the design and fabrication of an apparatus for visualization of two-phase flow and for measurement of gas-liquid relative permeability in realistic rough-walled rock fractures. A transparent replica of a natural rock fracture from a core specimen is fabricated by molding and casting in clear epoxy. Simultaneous flow of gas and liquid with control of capillary pressure at inlet and outlet is achieved with the Hassler sandwich'' design: liquid is injected to the fracture through a porous block, while gas is injected directly to the edge of the fracture through channels in the porous block. A similar arrangement maintains capillary separation of the two phases at the outlet. Pressure drops in each phase across the fracture, and capillary pressures at the inlet and outlet, are controlled by means of pumps and needle valves, and are measured by differential and absolute pressure transducers. The clear epoxy cast of the natural fracture preserves the geometry of the fracture and permits visual observation of phase distributions. The fracture aperture distribution can be estimated by filling the fracture with a dyed liquid, and making pointwise measurements of the intensity of transmitted light.

Persoff, P.; Pruess, K.; Myer, L.

1991-01-01

26

Two-phase flow visualization and relative permeability measurement in transparent replicas of rough-walled rock fractures  

SciTech Connect

Understanding and quantifying multi-phase flow in fractures is important for mathematical and numerical simulation of geothermal reservoirs, nuclear waste repositories, and petroleum reservoirs. While the cubic law for single-phase flow has been well established for parallel-plate fractures theoretically and experimentally, no reliable measurements of multi-phase flow in fractures have been reported. This work reports the design and fabrication of an apparatus for visualization of two-phase flow and for measurement of gas-liquid relative permeability in realistic rough-walled rock fractures. A transparent replica of a natural rock fracture from a core specimen is fabricated by molding and casting in clear epoxy. Simultaneous flow of gas and liquid with control of capillary pressure at inlet and outlet is achieved with the Hassler ''sandwich'' design: liquid is injected to the fracture through a porous block, while gas is injected directly to the edge of the fracture through channels in the porous block. A similar arrangement maintains capillary separation of the two phases at the outlet. Pressure drops in each phase across the fracture, and capillary pressures at the inlet and outlet, are controlled by means of pumps and needle valves, and are measured by differential and absolute pressure transducers. The clear epoxy cast of the natural fracture preserves the geometry of the fracture and permits visual observation of phase distributions. The fracture aperture distribution can be estimated by filling the fracture with a dyed liquid, and making pointwise measurements of the intensity of transmitted light. A set of two-phase flow experiments has been performed which has proven the viability of the basic experimental design, while also suggesting further improvements in the apparatus. Preliminary measurements are presented for single-phase permeability to liquid, and for relative permeabilities in simultaneous flow of liquid and gas.

Persoff, P.; Pruess, K.; Myer, L.

1991-01-01

27

Initial Melting and wall-rock flux-melting of a wet multi-component mantle and its implications for the formation of MORB  

NASA Astrophysics Data System (ADS)

We explore several simple scenarios for wet melting of a heterogeneous multi- component mantle. In our melting formulation the mantle is viewed as a mixture consisting of a heterogeneously depleted peridotite matrix with embedded veins of fertile peridotite and/or geochemically enriched pyroxenite. These lithological units differ in their mineral composition but are assumed to have diffusively equilibrated both their water/hydrogen content and temperature over the hundreds of millions to billions of years prior to entering a melting region. During the melting process, however, only thermal but not chemical (water) equilibrium is assumed between the lithologies, which is a reasonable assumption for veins with thicknesses on the order of few tens to few hundreds of meters, a thermal diffusivity of 10^-6 m^2/s and a diffusivity of hydrogen of less than 3*10^-9 m^2/s. The thermodynamic formulation of the multi-component melting process, during which all components have to share thermal energy, is based on Phipps Morgan (2001). The wet melting parameterization by Katz et al. (2003) has been included in the thermodynamic formulation by modifying its solidus-depletion-dependence and treating water partitioning during melting as partitioning of a trace element with a D-value like that of Ce. Usually, fractional melting with a small trapped melt fraction is assumed. We will mostly discuss results from 1-D model calculations, which represent the idealized decompression of a multi-component mantle rising underneath a mid-ocean ridge. Melt-migration is assumed to occur as vertical ascent within each column. We have also extended the formulation to examine the effects of rising melts on 'flux-melting' the wall-rock through which they migrate. We are still testing to see if this mechanism can be the reason why ridge melts almost always have major element chemistries in equilibrium with a peridotitic mantle, while the incompatible trace elements in EMORB reflect the influence of volumetrically small heterogeneities within the heterogeneous source. We hypothesize that rising melt will cause rapid and limited flux-melting in adjacent wall-rock as long as the melt+wall-rock system generates a larger equilibrium melt volume than the initial local melt volume, and that the preferred amount of local flux-melting is equal to the maximum amount of potential local flux-melting. (e.g., the volume fraction of wall-rock that interacts with melt is the fraction that maximizes the productivity of flux-melting.) As local flux-melting consumes latent-heat, wall-rock flux melting also reduces shallower melt-productivity of the assemblage. Since the hydrogen diffusion rate is too low to equilibrate the water contents of veins and surrounding matrix within the melting zone, dry and wet lithologies can coexist next to each other. Considering the dehydration related increase in viscosity for each lithology, the aggregate viscosity remains low until the last (most depleted) major lithology starts to melt -- e.g. until the most refractory harzburgites cross their wet solidus.

Morgan, J. P.; Hasenclever, J.

2013-12-01

28

Geologic Maps Geology 200  

E-print Network

Geologic Maps Geology 200 Geology for Environmental Scientists #12;Geologic Map of the US #12;Symbols found on geologic maps #12;Horizontal Strata #12;Geologic map of part of the Grand Canyon. Each color represents a different formation. #12;Inclined Strata #12;Dome #12;Geologic map of the Black Hills

Kammer, Thomas

29

Geologic Constraints on Conduit Formation at Explosive Basaltic Volcanoes  

NASA Astrophysics Data System (ADS)

Models of explosive basaltic processes often are sensitive to shallow (<2 km) conduit dimensions. Geologic data constrain how these conduits can evolve. Xenoliths in the 1975 Tolbachik, Kamchatka, violent strombolian basalt eruption are derived from Quaternary volcanic (0-1 km deep) and Tertiary sedimentary (1-4 km) rocks. Xenolith abundances in the lower half of fall deposits from the Cone 1 eruption stage are 0.001-0.01 vol%. This period sustained 6-10-km high eruption columns and lacked lavas. Xenolith abundances increase to 0.01-1.0 vol% in the upper half of the deposits, which correlates with lava effusion and columns 2-6-km high. The 3x105 m3 total xenolith volume represents a cylindrical conduit 15+/-2 m in diameter and 1.7+/-0.2 km deep. Eruption of Cone 1 ended with 12 hr of hydromagmatic falls containing 3x106 m3 (70 vol%) xenoliths. The conduit must have widened from 15+/-2 to 48+/-4 m to produce this xenolith volume. The subsequent Cone 2-3 eruption stage produced abundant lavas and eruption columns <4-km high. Xenolith abundances are 0.01-0.1 vol%, indicating progressive widening of the conduit to 6+/-1 m extending to 2.8+/-0.4 km depth. Simultaneous eruptions of tephra and lava suggest an annulus of degassed magma developed on conduit walls, enhancing xenolith entrainment; little entrainment occurred early at Cone 1 with an apparent droplet flow regime. Alkali basalt plugs and dikes representing 1+/-0.5 km paleodepths are exposed in the 4 Ma San Rafael volcanic field, Utah. Dike-plug complexes represent typical dimensions for basaltic volcanic eruptions and are interpreted as subvolcanic conduit systems. Mapped conduits range from 2-m wide buds along dikes with little wall-rock disruption, to 10-60-m wide cylindrical plugs having <5-m wide conduit margins with abundant xenoliths. These margins may represent typical wall-rock plucking and conduit widening during annular flow (i.e., late Cone 1 and Cone 2-3). Several larger conduits, however, have a 1-6 m xenolith-poor annulus with a 10-40 m inner core of extensive wall-rock breccia and pervasive low-temperature hydrothermal alteration. Xenoliths in the inner breccia often are derived from deeper stratigraphic units. These brecciated conduits appear analogous to late-stage hydromagmatic events at Cone 1. Models of explosive basaltic cinder cone eruptions should consider that subvolcanic conduit diameters to <2 km depth may progressively widen to order of 10-60 m. Work supported by U.S. Nuclear Regulatory Commission (Contract NRC-02-97-009) and is an independent product of CNWRA that does not necessarily reflect NRC views or regulatory positions.

Hill, B. E.; Doubik, P.; Connor, C. B.

2001-12-01

30

Paris Basin, seal integrity Predicting long-term geochemical alteration of wellbore cement in a generic geological CO21  

E-print Network

Paris Basin, seal integrity 1 Predicting long-term geochemical alteration of wellbore cement degradation of the cement filling of these wells is a key issue to insure the confinement of the CO2 modeling stands as a powerful means to predict the long-term evolution of the cement15 plugs, and to assess

Paris-Sud XI, Université de

31

Predicting long-term geochemical alteration of wellbore cement in a generic geological CO 2 confinement site: Tackling a difficult reactive transport modeling challenge  

NASA Astrophysics Data System (ADS)

SummaryThe safety of the future CO 2 geological storage is largely dependent on the integrity of existing surrounding wells. Well integrity is of major concern in confinement sites where the number of abandoned wells is particularly high, such as it often occurs in depleted gas and/or oil fields. The degradation of the cement filling of these wells is a key issue to insure the confinement of the CO 2. Laboratory experiments are unable to produce data for long periods of interaction; therefore, numerical modeling stands as a powerful means to predict the long-term evolution of the cement plugs, and to assess well integrity and leakage risk for the confining system. We thus present the results of a set of numerical simulations that predict the evolution of fluid chemistry and mineral alteration in the cement of an idealized abandoned wellbore at the top of the Dogger aquifer in Paris Basin, France, where CO 2 geological disposal is currently under consideration. A continuum-based reactive transport formulation has been adopted which accounts for multi-component reactivity under water saturated and diffusion-controlled mass transfer conditions. Simplified two-dimensional models have been applied to simulate the complex geochemical interactions occurring at the interfaces between cement, aquifer and caprock domains. The simulations predict a two-stage evolution of the cement porous matrix, after interaction with acid fluids from reservoir: (i) a first, "clogging" stage, characterized by a decrease in porosity due to calcite precipitation, and (ii) a second stage of porosity reopening, related to the disappearance of primary cement phases, and the re-dissolution of secondary minerals, such as zeolites. Overall, the interaction with acid fluids causes a severe mineralogical alteration of the cement and the development of a carbonated, low-porosity layer near the reservoir interface. As the caprock imposes a high partial pressure of CO 2, some mineralogical alteration of the cement is promoted also at the interface with the caprock. This pattern of reaction results in a large increase in porosity that might lead to the formation of vertical ascent route for reservoir fluids.

Gherardi, Fabrizio; Audigane, Pascal; Gaucher, Eric C.

2012-02-01

32

Geology, alteration, and magmatic-hydrothermal history of The Geysers felsite -- potential applications for exploration and development  

SciTech Connect

The [open quotes]felsite[close quotes] is a shallow, young, granitic intrusive body centrally located within and beneath. The Geysers steam field. The field and the felsite are coaxial, and hydrothermal alteration effected by hot-water dominated geothermal systems antedating the modern steam reservoir shows systematic vertical zonation with respect to the pluton. The research summarized in this communication was undertaken both to clarify the role of the pluton in reservoir evolution, and to characterize critical felsite-specific controls on the fields's deep porosity and permeability. The felsite comprises at least three major intrusive phases. Two are high-silica granites probably older than 1.3 Ma. The third is granodiorite (1 Ma), temporally and chemically equivalent to overlying extrusive dacites of the Clear Lake volcanic field. All three intrusive phases are too old to be heat sources for the modern steam field, but probably were the heat engines for the prior liquid-dominant systems. Younger, deeper magmatic heat sources are strongly implied for the current vapor-dominated regime. Porosity in the felsite is provided by: (1) Extensively mineralized fractures and breccias, probably of both tectonic and high-temperature hydrothermal origin; and (2) miarolitic cavities in the upper levels of the pluton. The latter could be analogous to calcite-dissolution cavities in overlying metagraywacke -- they could serve as storage sites for the fields's liquid water reserves. Porosity in these fractures, breccias, and vugs in partially occluded by hydrothermal vein minerals deposited in prior hotwater-dominated systems --tourmaline, ferroaxinite, quartz, potassium feldspar, epidote, actinolite, prehnite, and many others. Such secondary mineralization conceptually could serve as an excellent exploration guide to potentially productive portions of the felsite beyond the field's present boundaries.

Hulen, J.B.; Nielson, D.L. (Univ. of Utah Research Institute, Salt Lake City, UT (United States))

1993-01-01

33

Dynamics of changes in the physical characteristics of a hydrothermally altered geological section according to nonisothermal physicochemical simulation (the Mutnovsky Volcano)  

NASA Astrophysics Data System (ADS)

The paper presents the results of numerical simulation of a subaerial volcanic hydrothermal system. The model is based on the factual data on the rock composition and the geological structure of the Mutnovsky Volcano. We develop a new approach to construct the numerical model of a volcanic hydrothermal system. According to this approach, at each step of the calculation, for each point of the spatiotemporal domain, the thermophysical properties are determined; further, these properties are used in the calculation of the equilibrium state of the system. This procedure allows us to take into account the dynamic changes in the T-P conditions in the cross section and the migration of the phase boundaries. As well, using this approach, we can pass from "conditional" time in the description of the evolution of the magmagenic fluid system to the "virtually dimensional time" of the development of the simulated ore-magmatic system, from the onset of melt crystallization in the intrusive chamber up to the termination of the retrograde boiling of the melt. The simulation shows that, depending on the structure of the lower part of the section, contrasting hydrothermal systems can develop in the originally homogeneous medium. The relation between the temperature, and, therefore, phase composition of the fluid and the features of the hydrothermal alteration in volcanic rocks is demonstrated. Among other questions, in the present paper we discuss the changes in the density and magnetic properties of the volcanogenic section.

Bessonova, E. P.; Gora, M. P.; Shevko, A. Ya.; Chudnenko, K. V.; Cherepanova, V. K.

2011-06-01

34

Geologic map of the Sulphur Springs Area, Valles Caldera Geothermal System, New Mexico  

SciTech Connect

The geologic and tectonic setting and geology of Sulphur Springs Area are described. Geologic faults, sheared or brecciated rock, volcanic vents, geothermal wells, hydrothermal alteration, springs, thermal springs, fumaroles, and geologic deposits are indicated on the map. (MHR)

Goff, F.E.; Gardner, J.N.

1980-12-01

35

Ad Duwayhi, Saudi Arabia: Geology and geochronology of a neoproterozoic intrusion-related gold system in the Arabian shield  

USGS Publications Warehouse

The Ad Duwayhi gold deposit, located in the east-central part of the Arabian shield, is the newest gold discovery in Saudi Arabia. Exploration to date has identified a gold resource of greater than 1 million ounces (oz) with significant potential for expansion. Gold mineralization was closely associated, in time and space, with emplacement of a late- to postorogenic, intracrustal, northwest-oriented granite body (659 ?? 7 Ma) and comagmatic square quartz porphyry (646 ?? 11 Ma), a hypabyssal and perhaps younger phase of the granite. Mineralization was largely confined to northeast-striking, southeast-dipping fault zones. Hydrothermal alteration consisted of early biotitic alteration overprinted by sericitic alteration. Sericitic alteration was coincident with gold mineralization and produced a quartz-sericite-carbonate-pyrite-rutile mineral assemblage, found both as vein fill and wall-rock alteration products. Mineralization styles, in the following general paragenetic sequence, include (1) quartz-molybdenite veins in and near the granite stock, (2) low-grade gold-bearing quartz vein breccia in and along the margins of the granite stock, (3) gold-bearing stockwork and sheeted quartz veins, and (4) massive to banded gold-rich tabular quartz veins. The gold-bearing stockwork, sheeted, and tabular veins are generally spatially associated with square quartz porphyry dikes and more distal to the granite stock. Mineralized zones at Ad Duwayhi are characterized by low sulfide and base metal content and gold/silver ratios of approximately 6/1. Gold shows no significant correlation with other metals, except lead, and moderate correlation with silver. Re-Os dating of molybdenite from a quartz-molybdenite vein and a tabular quartz vein with cogenetic gold produced robust ages of 655.6 ?? 2.7 and 649.9 ?? 2.3 Ma, respectively, documenting that gold mineralization and crystallization of granite and square quartz porphyry were, within uncertainty, coeval events. This age correlation combined with granite textural features, the presence of unidirectional solidification textures in granite and square quartz porphyry, and the nature and time-space distribution of mineralization styles, all indicate that mineralization evolved in and near the interface between a crystallizing magma and the surrounding rocks and, thus, is consistent with an intrusion-related genesis. In light of our findings at Ad Duwayhi, a reassessment of similar intrusion-hosted deposits in the Arabian shield is warranted, and areas of late- to postorogenic plutonism, particularly in the Afif composite terrane, should be considered prospective for intrusion-related gold systems. ??2004 by Economic Geology.

Doebrich, J.L.; Zahony, S.G.; Leavitt, J.D.; Portacio, J.S., Jr.; Siddiqui, A.A.; Wooden, J.L.; Fleck, R.J.; Stein, H.J.

2004-01-01

36

Geological structures  

Microsoft Academic Search

Here is an account of recent thinking in structural geology and tectonics. The book begins with a discussion of the history of geological structures, their division, and research techniques. It then introduces a broad range of viewpoints. Using examples, the book examines geological structures in the context of their geographical location. It considers the tectonic mechanisms which produce geologic structures.

T. Uemura; S. Mizutani

1984-01-01

37

Geologic Maps  

NSDL National Science Digital Library

Geologic Maps are unique in that they show the distribution of geologic features on a landscape through specific symbols and colors. The United States Geological Survey's (USGS) site Geologic Maps provides visitors with a good introduction to these concepts, which include the unique features of a geologic map; the meaning of their lines, colors, and symbols; the location of faults; and more. Anyone working with geologic maps or just interested in learning a little about cartography or geology will find this site easy to explore and full of good information.

2000-01-01

38

Geology of five small Australian impact craters  

USGS Publications Warehouse

Here we present detailed geological maps and cross-sections of Liverpool, Wolfe Creek, Boxhole, Veevers and Dalgaranga craters. Liverpool crater and Wolfe Creek Meteorite Crater are classic bowlshaped, Barringer-type craters, Liverpool was likely formed during the Neoproterozoic and was filled and covered with sediments soon thereafter. In the Cenozoic, this cover was exhumed exposing the crater's brecciated wall rocks. Wolfe Creek Meteorite Crater displays many striking features, including well-bedded ejecta units, crater-floor faults and sinkholes, a ringed aeromagnetic anomaly, rim-skirting dunes, and numerous iron-rich shale balls. Boxhole Meteorite Crater, Veevers Meteorite Crater and Dalgaranga crater are smaller, Odessa-type craters without fully developed, steep, overturned rims. Boxhole and Dalgaranga craters are developed in highly follated Precambrian basement rocks with a veneer of Holocene colluvium. The pre-existing structure at these two sites complicates structural analyses of the craters, and may have influenced target deformation during impact. Veevers Meteorite Crater is formed in Cenozoic laterites, and is one of the best-preserved impact craters on Earth. The craters discussed herein were formed in different target materials, ranging from crystalline rocks to loosely consolidated sediments, containing evidence that the impactors struck at an array of angles and velocities. This facilitates a comparative study of the influence of these factors on the structural and topographic form of small impact craters. ?? Geological Society of Australia.

Shoemaker, E.M.; Macdonald, F.A.; Shoemaker, C.S.

2005-01-01

39

Geological images  

NSDL National Science Digital Library

This site from Marli Bryant Miller, a professor at the University of Oregon, presents images of geological features from around the world. Photographs of glacial features, igneous and metamorphic rocks and processes, and structural geology are featured.

Miller, Marli B.; Oregon, University O.

40

Geological Time  

NSDL National Science Digital Library

"Why do engineers need to know about geologic time?" That question is answered in this resource from the University of Saskatchewan's Department of Civil and Geological Engineering. Provided here is a discussion of the concepts of geological time; relative dating methods, such as correlation; and absolute dating methods, such as radiometric methods. Diagrams and charts are included to demonstrate these complex concepts.

2008-04-17

41

Geology and origin of Ag-Pb-Zn deposits occurring in the Ulaan-Jiawula metallogenic province, northeast Asia  

NASA Astrophysics Data System (ADS)

Located at the conjunction area of China, Mongolia and Russia in NE Asia, the Ulaan-Jiawula (also referred as UJ) region, with an area of 400,000 km2, is one of the most important Ag-Pb-Zn, U, Sn, W, Nb-Ta, and Au metallogenic provinces in Asia. At present, 2126 deposits and showings including 500 Ag-Pb-Zn deposits have been discovered, explored and mined since the late 1960s. These Ag-Pb-Zn occurrences can be subdivided into three types according to their geological setting, texture, alteration and mineral assemblages: (1) low sulfidation epithermal Ag-Pb-Zn deposits; (2) intermediate sulfidation epithermal Ag-Pb-Zn deposits; (3) mixed-type Ag-Pb-Zn deposit consisting of vein-like and tabular ore bodies. The Eren Tologoi and Tsagenbulagen deposits are representative of low-sulphidation type Ag-Pb-Zn mineralization in the UJ region, and are associated with intensive adularization and sericitization. Ore occurs as mineralized quartz veins, veinlet groups and altered-fracture zones within Mesozoic alkaline and high-K calc-alkaline volcanic rocks, Ore mineralogy includes native silver, electrum, pyrite, galena, sphalerite, arsenopyrite, pyrargyrite and chalcopyrite. The Tsav and Jiawula deposits are typical of intermediate sulfidation Ag-Pb-Zn mineralization. The ?34S value of sulfide (pyrite and galena) separates from groups 1 and 2 varies from 1.5‰ to 3.5‰ and 2.0‰ to 4.5‰, respectively. The ?34S values of the Mesozoic volcanic host rocks for groups 1 and 2 deposits also show the positive ?34S values of 1.5-4.8‰, while the ?34S value of pyrite separate from the pre-Jurassic schist range from -6‰ to -8‰ which are much lower than Mesozoic volcanic host rocks and their associated ore deposits. There is no difference between the ?34S value of sulfide (pyrite and galena) separates from vein-like ore bodies of the group 3 deposits and their wall rocks, having ?34S value of 1.0-5.0‰ and 1.2-4.5‰ which are similar to that of groups 1 and 2 deposits. For the Mesozoic monzogranite porphyry dykes and their associated tabular skarn ore bodies, the pyrite separates show ?34S values of 2-5‰ and 1.8-3‰. All of these deposits show relatively radiogenic lead isotopic compositions compared to mantle or lower crust curves. Most lead isotope data of sulfides from the Ag-Pb-Zn ores plot between the Mesozoic volcano-hypabyssal rocks and pre-Jurassic metamorphic rocks. Monzogranite dykes at Ulaan and Noyon Tologoi have ?Nd (T) values ranging from 1.5 to 4.5 that are similar to most of the Mesozoic granite with positive ?Nd (T) values in the Great Hinggan Mountains-Mongolia orogenic belt. Data are interpreted as indicative of a mixing of ore-forming materials from mantle-derived alkaline and high-K calc-alkaline magma with these from pre-Jurassic metamorphic wall rocks. Isotopic age data, geological and geochemical evidence suggest that the ore fluids for the Ag-Pb-Zn deposits were generated during eruption or emplacement of the Mesozoic alkaline and high-K calc-alkaline magma. The Mesozoic magmas may provide heat, volatiles and metals for the group 1 and 2 deposits. Evolved metamorphic fluids produced by devolatilization, circulated the wall rocks, were also progressively involved in the magmatic hydrothermal system, and may have dominated the ore fluids during late stage ore-forming processes. Most of the Ag-Pb-Zn bodies that occur along the contact of the pre-Jurassic marble and Cretaceous monzogranite porphyry dykes at Ulaan and Noyon Tologoi are closely associated with skarn. The ore fluid of these group 3 deposit may have resulted from the mixing of Mesozoic magmatic water and evolved metamorphic fluids. Ore deposition in this instance would be the product of the interaction of the Mesozoic intrusions and pre-Jurassic carbonate rocks.

Nie, Feng-jun; Li, Qiang-feng; Liu, Chun-hua; Ding, Cheng-wu

2015-01-01

42

California Geological Survey: Geologic Maps  

NSDL National Science Digital Library

This index provides access to a selection of geologic maps of California, as well as an overview of geologic and other mapping activities in the state. The index, which can be accessed by clicking on an interactive map of the state, contains lists of selected geologic maps in California prepared by the Regional Geologic Mapping Project (RGMP). The RGMP staff monitors the literature and collects references that contain geologic mapping that may be useful for future compilations. In addition, the site has information about Caltrans Highway Corridor Mapping, The Mineral Resources and Mineral Hazards Mapping Program, North Coast Watersheds Assessment Program, The Timber Harvesting Plan Enforcement Program, and The Seismic Hazards Mapping Program. A set of links is provided to other sources of geologic maps and map information.

43

Hydrothermal alteration, ore fluid characteristics, and gold depositional processes along a trondhjemite-komatiite contact at Tarmoola, Western Australia  

USGS Publications Warehouse

Tarmoola is a structurally controlled Archean orogenic gold deposit hosted in greenschist facies metamorphosed komatiite and trondhjemite in the Leonora district of the Eastern Goldfields province, Yilgarn craton. High-grade (>1 g/t Au) orebodies are located in komatiite wall rock adjacent to the eastern and northeastern margins of the asymmetrical, north-south-striking, Tarmoola trondhjemite intrusion. Gold-bearing veins post-date trondhjemite emplacement (ca. 2700 Ma), quartz diorite dikes (ca. 2667 Ma), and regional greenschist facies metamorphism. Textures and crosscutting relationships in gold-bearing veins indicate two stages of hydrothermal fluid infiltration associated with a single gold-related hydrothermal event: a volumetrically dominant, but gold-poor, stage I fluid and a gold-rich stage II fluid. Gold-bearing veins contain stage I milky quartz and pyrite that are overprinted by stage II quartz-ankerite-muscovite-chalcopyrite-sphalerite-galena-gold-tellurides ?? albite ?? chlorite ?? fuchsite ?? epidote ?? scheelite. Stage I hydrothermal alteration assemblages are different in trondhjemite and komatiite due to contrasting reactions between a common ore fluid and disparate wall-rock chemistry. Stage II fluid-wall rock interaction was minor compared to stage I and is indicated by the overprinting of stage I mineral assemblages by stage II microveins. Wall-rock alteration proximal to veins in trondhjemite is characterized by replacement of igneous plagioclase, amphibole, biotite, and metamorphic chlorite by hydrothermal quartz, muscovite, ankerite, calcite, pyrite, chalcopyrite, sphalerite, galena, tellurides, and gold, whereas in proximal alteration in komatiite, metamorphic chlorite and talc are replaced by ankerite, quartz, muscovite, albite, chlorite, fuchsite, pyrite, chalcopyrite, sphalerite, galena, tellurides, and gold. The stage II fluid was enriched in H2O, CO2, Si, Ca, K, Na, S, Au, Ag, Cu, Pb, W, Bi, As, Mo, Zn, and Te. Based on fluid inclusion studies and stage II mineral equilibria, gold deposited from a homogeneous, neutral to slightly alkaline (pH 5.1-5.5), reduced, low-salinity (<5.5 wt % NaCl equiv) fluid that had a bulk composition of 78 mole percent H2O and 21 mole percent CO2, and trace amounts of CH4, C2H6, H2, Ar, H2S, and He. Gold deposition occurred at 300?? ?? 50??C and 0.5 to 3.0 kbars. Assuming lithostatic fluid pressures, gold precipitated at a 2- to 10-km depth. Stage II gray quartz ??18Ofluid values range from 5.9 to 7.5 per mil, whereas ??Dfluid values calculated from the dehydration of muscovite grains and measured directly from bulk fluid inclusion analyses of stage II gray quartz have ranges of -9 to -35 and -27 to -28 per mil, respectively. Hydrothermal ore fluids were transported from greater crustal depths to the site of gold deposition during the district-scale D3 event by shallowly W dipping, reverse brittle-ductile shear zones in supracrustal rock and along the steeply east dipping trondhjemite contact. Associated subhorizontal east-west shortening caused the reactivation of the eastern trondhjemite margin and subparallel foliation, which facilitated the transport of hydrothermal fluids and the generation of gold-bearing veins and hydrothermal alteration zones in komatiite. East-west-striking fractures in trondhjemite aided the lateral migration of ore fluids away from trondhjemite margins and the formation of east-west-striking gold-bearing veins and broad alteration zones. Gold was most likely transported in the stage II fluid as bisulfide complexes. The sulfidation of trondhjemite and komatiite wall rock by the stage II fluid caused the destabilization of An bisulfide complexes and gold deposition. Potassium, Ca, and CO2 metasomatism of komatiite wall rock may have enhanced gold deposition via the acidification of the stage II fluid. The physicochemical characteristics of the Tarmoola ore fluid and relative timing of gold mineralization are consistent with the Yilgarn-wide,

Duuring, P.; Hagemann, S.G.; Cassidy, K.F.; Johnson, C.A.

2004-01-01

44

Yosemite Geology  

NSDL National Science Digital Library

The National Park Service maintains the Yosemite National Park Web site and the corresponding Geology page. This Web site gives an overview of the geologic history of the site, tells how the Sierra Nevada range formed, explains the basics of granitic rock, shows how glaciers carved out the canyons, and much more.[JAB

45

Geologic Time.  

ERIC Educational Resources Information Center

One of a series of general interest publications on science topics, the booklet provides those interested in geologic time with an introduction to the subject. Separate sections discuss the relative time scale, major divisions in geologic time, index fossils used as guides for telling the age of rocks, the atomic scale, and the age of the earth.…

Newman, William L.

46

Geological Time  

Microsoft Academic Search

IN his Presidential Address to Section C at Dover, Sir A. Geikie has offered a bold challenge to Lord Kelvin and those who agree with him by calling upon them to give due weight to geological phenomena in forming an estimate of geological time. Permit me to say what I think about it.

O. Fisher

1899-01-01

47

Yellowstone Geology  

NSDL National Science Digital Library

This Yellowstone National Park website provides geological information about the Park. Links include geologic highlights, hydrothermal features, reports by park geologists, and scientists' talks (videos). A wide array of information can be found on these links and the webpage is expanding as more topics are added.

Park, Yellowstone N.

48

Engineering Geology  

ERIC Educational Resources Information Center

Engineering geology remains a potpourri of applied classical geology, and 1977 witnessed an upswing in demand for these services. Traditional foundation-related work was slight, but construction related to national needs increased briskly. Major cities turned to concerns of transit waste-water treatment and solid-waste disposal. (Author/MA)

Hatheway, Allen W.

1978-01-01

49

Geology Major www.geology.pitt.edu/undergraduate/geology.html  

E-print Network

Geology Major www.geology.pitt.edu/undergraduate/geology.html Revised: 03/2013 Geology is a scientific discipline that aims to understand every aspect of modern and ancient Earth. A degree in geology the field of geology, environmental and geotechnical jobs exist for people with BS degrees. A master

Jiang, Huiqiang

50

No geology without marine geology  

Microsoft Academic Search

A brief review is offered of the many problems where knowledge of the ocean floors and of marine processes in shallow water is indispensable for the further advancement of geology. The subject of turbidity currents is treated in greater detail, to demonstrate the interrelation of several aspects of marine geology with sedimentologic and paleogeographic investigations. It is obvious that the

P. H Kuenen

2002-01-01

51

Geologic History  

NSDL National Science Digital Library

This unit introduces younger students to the concept of relative versus absolute time and how geologists determine the age of geologic events and features. Topics include the laws that determine relative age (superposition, cross-cutting relationships, included fragments, and others), and how to re-construct the geologic history of an area using these relationships. There is also information on geologic correlation and the use of index fossils to determine relative age. The section on absolute time discusses some ways of measurement (tree rings, radioactive dating) and introduces the concepts of natural selection and mass extinctions. A vocabulary and downloadable, printable student worksheets are provided.

Medina, Philip

2010-09-03

52

Geologic Time  

NSDL National Science Digital Library

The Earth is very old -- 4.5 billion years or more -- according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science.

Newman, William L.

1997-01-01

53

Geologic time  

USGS Publications Warehouse

The Earth is very old 4 1/2 billion years or more according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science.

Newman, William L.

2000-01-01

54

Geologic Timeline  

NSDL National Science Digital Library

Dive into the depths of time with this Geologic Timeline. The farther you scroll down, the farther back in time you'll travel. Also, the longer a period is on this page, the longer it lasted in history!

2000-01-01

55

Geology, summary  

NASA Technical Reports Server (NTRS)

Trends in geologic application of remote sensing are identified. These trends are as follows: (1) increased applications of orbital imagery in fields such as engineering and environmental geology - some specific applications include recognition of active earthquake faults, site location for nuclear powerplants, and recognition of landslide hazards; (2) utilization of remote sensing by industry, especially oil and gas companies, and (3) application of digital image processing to mineral exploration.

Sabins, F. F., Jr.

1975-01-01

56

Alteration and geochemical zoning in Bodie Bluff, Bodie mining district, eastern California  

USGS Publications Warehouse

Banded, epithermal quartz-adularia veins have produced about 1.5 million ounces of gold and 7 million ounces of silver from the Bodie mining district, eastern California. The veins cut dacitic lava flows, pyroclastic rocks and intrusions. Sinter boulders occur in a graben structure at the top of Bodie Bluff and fragments of sinter and mineralized quartz veins occur in hydrothermal breccias nearby. Explosive venting evidently was part of the evolution of the ore-forming geothermal systems which, at one time, must had reached the paleosurface. Previous reconnaissance studies at Bodie Bluff suggested that the geometry of alteration mineral assemblages and distribution of some of the major and trace elements throughout the system correspond to those predicted by models of hot-spring, volcanic rock hosted precious metal deposits (Silberman, 1982; Silberman and Berger, 1985). The current study was undertaken to evaluate these sugestions further. About 500 samples of quartz veins and altered rocks, including sinter, collected over a vertical extent of 200 meters within Bodie Bluff were petrographically examined and chemically analyzed for trace elements by emission spectrographic and atomic absorption methods. Sixty-five samples were analyzed for major elements by X-ray fluorescence methods. The results of these analyses showed that, in general, alteration mineral assemblage and vertical geochemical zoning patterns follow those predicted for hot-spring deposits, but that geochemical zoning patterns for sinter and quartz veins (siliceous deposits), and altered wall rocks are not always similar. The predicted depth-concentration patterns for some elements, notably Au, Ag, Hg, and Tl in quartz veins, and Hg, As and Ag in wall rocks were not as expected, or were perturbed by the main ore producing zone. For both quartz veins and altered wall rocks, the main ore zone had elevated metal contents. Increased concentration of many of these elements could indicate proximity to this zone. However, irregularities in the distribution of some key elements, such as Au and Ag, relative to the predictive models suggest that a larger suite of elements be considered for exploration for ore zones within the district. ?? 1993.

Herrera, P.A.; Closs, L.G.; Silberman, M.L.

1993-01-01

57

Geology of the Plumtree area, Spruce Pine district, North Carolina  

USGS Publications Warehouse

This report describes the results of study and geologic mapping (1:12,000) in the 70-square-mile Plumtree area in the northeastern part of the Spruce Pine pegmatite district, on the Blue Ridge upland in western North Carolina. The district has been the chief domestic source of feldspar and sheet mica. The mining belt just west of the Blue Ridge Front trends northeast and is 25 miles long and 10 miles wide. The center of the Plumtree area lies 10 miles northeast of Spruce Pine pegmatite district, on the Blue Ridge upland in western North Carolina. The district has been the chief domestic source of feldspar and sheet mica. The mining belt just west of the Blue Ridge Front trends northeast and is 25 miles long and 10 miles wide. The center of the Plumtree area lies 10 miles northeast of Spruce Pine and includes parts of Mitchell and Avery Counties shown on the portions of the 7.5-minute Spruce Pine, Linville Falls, Newland, North Carolina, and Carvers Gap, North Carolina and Tennessee quadrangle. The topography varies from rugged mountains to rounded or flat topped hills near the entrenched, meandering master streams. Old erosion surfaces are approximately 600,1,100, 1,500, and 2,500 feet above the present master stream level. The area is in late youth or early maturity after rejuvenation.. The regionally metamorphosed rocks of the amophibolite facies form three mappable units: mica gneiss, mica schist, and hornblende rock. These rocks, perhaps of Precambrian age, are intimately interlayered with thicknesses of the individual layers ranging from less than one inch to several tons of feet. Field relationships and chemical data suggest that the mica (Carolina-type) rocks were derived from sandstones, graywackes, and shales and that the hornblende-rich (Roan-type) layers were derived from impure carbonate rocks. The igneous rocks include alaskite and associated pegmatite of early Paleozoic age (?), dunite and associated soapstone of a prepegmatite age, and a few diabasic dikes of post-pegmatite age (Triassic?). The alaskite and pegmatite have similar bulk compositions, notably low in iron (0.3 percent). The major constituents in order of decreasing abundance are plagioclase, perthitic microcline, quartz, and muncovite. All of these minerals, as well as clay deposits derived from the weathering of alaskite under old terraces, have economic value. The zoned pegmatites contain fewer zones which are less complex mineralogically than those in the pegmatites of many other areas. These essentially unmetamorphosed bodies were intruded approximately at the peak of the regional metamorphism. Their emplacement was controlled by local structure and rock type. The source of this igneous material may have been the mobilized portions of the Cranberry gneiss which underlies the area. The dunite bodies were intruded early in the metamorphic cycle. The bodies are commonly zoned: from the wall rock inwards (1) talc-antrophyllite-serpentine fringe, (3) serpentinized dunite, (3) granular olivine core. Dunite, chromite, vermiculite, and anthophyllite are the major economic commodities. Extensive hydrothermal alteration of dunite bodies produced soapstone. The area is the northeast end of a southwest plunging synclinorium about 20 miles wide with the steeper limb on the northwest side. There are three structural zones: zone I on the northwest is characterized by the northeast-trending isoclinal folds with steep southeast dips; zone II on the southwest includes an area of rocks with low and variable dip; zone III is the complex central core. In the extreme northeast zones I and II have an indistinct boundary where they coalesce along the rim of the synclinorium. Six stratigraphic units are exposed totaling approximately 10,500 feet of metamorphic rocks. Small scale structural features include a foliation, and a lineation in the planes of the foliation. Minor folding reflects the trends of the major structures. There are randomly orient

Brobst, Donald Albert

1953-01-01

58

Geologic mapping of the air intake shaft at the Waste Isolation Pilot Plant  

SciTech Connect

The air intake shaft (AS) was geologically mapped from the surface to the Waste Isolation Pilot Plant (WIPP) facility horizon. The entire shaft section including the Mescalero Caliche, Gatuna Formation, Santa Rosa Formation, Dewey Lake Redbeds, Rustler Formation, and Salado Formation was geologically described. The air intake shaft (AS) at the Waste Isolation Pilot Plant (WIPP) site was constructed to provide a pathway for fresh air into the underground repository and maintain the desired pressure balances for proper underground ventilation. It was up-reamed to minimize construction-related damage to the wall rock. The upper portion of the shaft was lined with slip-formed concrete, while the lower part of the shaft, from approximately 903 ft below top of concrete at the surface, was unlined. As part of WIPP site characterization activities, the AS was geologically mapped. The shaft construction method, up-reaming, created a nearly ideal surface for geologic description. Small-scale textures usually best seen on slabbed core were easily distinguished on the shaft wall, while larger scale textures not generally revealed in core were well displayed. During the mapping, newly recognized textures were interpreted in order to refine depositional and post-depositional models of the units mapped. The objectives of the geologic mapping were to: (1) provide confirmation and documentation of strata overlying the WIPP facility horizon; (2) provide detailed information of the geologic conditions in strata critical to repository sealing and operations; (3) provide technical basis for field adjustments and modification of key and aquifer seal design, based upon the observed geology; (4) provide geological data for the selection of instrument borehole locations; (5) and characterize the geology at geomechanical instrument locations to assist in data interpretation. 40 refs., 27 figs., 1 tab.

Holt, R.M.; Powers, D.W. (IT Corporation (USA))

1990-12-01

59

Pennsylvania Geology  

NSDL National Science Digital Library

Three decades after it was published, the Second Geological Survey of Pennsylvania was described as "the most remarkable series of reports ever issued by any survey." Considering the diversity of other geological reports, this was no small compliment. Drawing on support from the Marion and Kenneth Pollock Libraries Program Fund, the Pennsylvania State University Libraries' Digital Preservation Unit was able to digitize not only this fabled Survey, but also the Third and Fourth Surveys as well. Visitors can use the search engine on the homepage to look for items of interest, or they can just browse through the collection at their leisure. The surveys include various maps and illustrations that track mineral deposits and the disposition and location of other natural resources. Additionally, users can look through a miscellaneous set of publications from the early 20th century related to survey work performed by the U.S. Geological Survey.

60

Teaching Geology  

NSDL National Science Digital Library

This rather remarkable website contains a great collection of resources for web-based instruction and demonstrations of geology concepts. The collection includes, under Classroom demonstration, the very useful SeisMac 3.0, which is an application for Mac OS X that turns a laptop computer into a " low-resolution strong-motion accelerometer," or a basic seismograph. It works by accessing the computer's Sudden Motion Sensor in order to display real-time, three axis accelerations graphs. Visitors can use the application to watch the seismic waves go up and down just by tapping their feet on the floor nearby. Other resources include Virtual Earth (an "interactive minicourse on thermal convection") and a link to Geology in the news, which collates important news stories with a geological theme.

61

Geological flows  

E-print Network

In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

Yu. N. Bratkov

2008-11-19

62

Antarctica Geology  

NSDL National Science Digital Library

This site contains information about the continent of Antarctica. There is a classroom practice and instructional module. The students will be able to describe the general geology of the land under the Antarctic ice and to explain from where the rocks may have come.

63

Geologic Time  

NSDL National Science Digital Library

This site contains 24 questions on the topic of geologic time, which covers dating techniques and unconformities. This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate feedback.

Heaton, Timothy

64

Geology Fieldnotes  

NSDL National Science Digital Library

This National Park Service (NPS) site delivers a brief description of the geology of the Black Hills National Park. Links to park maps, a photo album, books, videos, CDs, and a searchable data base of research needs that have been identified by the National Park Service are included. General information about the park's education and interpretive programs are also abailable.

National Park Services (NPS)

65

Physical Geology  

NSDL National Science Digital Library

This Tulane University course covers the nature of the Earth, the development of its surficial features, and the results of the interaction of chemical, physical, and biological factors on the planet. Lecture notes are about energy and minerals; igneous, metamorphic and sedimentary rocks; weathering and soils; geologic time; mass wasting; streams; groundwater; wind action and deserts; oceans; deformation of rock; earthquakes and the interior of the Earth; global tectonics; planetary changes; and glaciers.

Stephen Nelson

66

Vesta: A Geological Overview  

NASA Astrophysics Data System (ADS)

Observations from the Dawn spacecraft [1] enable the derivation of the asteroid 4Vesta's shape, facilitate mapping of the surface geology, and provide the first evidence for interpreting Vesta's geological evolution. Science data were acquired during the approach to Vesta, a circular polar (Survey) orbit at an altitude of 2700 km providing ~ 230 m/pix camera scale, and during a circular high-altitude mapping orbit (HAMO) at 700 km altitude with a camera scale of ~ 65 m/pixel. Currently Dawn is orbiting Vesta in a low-altitude mapping orbit (LAMO) at 210 km altitude, yielding a global image coverage of ~20 m/pixel at the time of EGU [2,3,4,5]. Geomorphology and distribution of surface features provide evidence for impact cratering, tectonic activity, and regolith and probable volcanic processes. Craters with dark rays, bright rays, and dark rim streaks have been observed, suggesting buried stratigraphy. The largest fresh craters retain a simple bowl-shaped morphology, with depth/diameter ratios roughly comparable to lunar values. The largest crater Rheasilvia, an ~500 km diameter depression at the south pole, includes an incomplete inward facing cuspate scarp and a large central mound surrounded by unusual complex arcuate ridge and groove patterns, and overlies an older ~400 km wide basin. A set of large equatorial troughs is related to these south polar structures. Vesta exhibits rugged topography ranging from -22 km to +19 km relative to a best fit ellipsoidal shape. Vesta's topography has a much greater range in elevation relative to its radius (15%) than do the Moon and Mars (1%) or the Earth (0.3%), but less than highly battered smaller asteroids like Lutetia (40%). This also identifies Vesta as a transitional body between asteroids and planets. The surface of Vesta exhibits very steep topographic slopes that are near the angle of repose. Impacts onto these steep surfaces, followed by slope failure, make resurfacing - due to impacts and their associated gravitational forces and seismic activity - an important geologic process on Vesta that significantly alters the morphology of geologic features and adds to the complexity of its geologic history. In general, Vesta's geology is more like the Moon and rocky planets than other asteroids.

Jaumann, R.

2012-04-01

67

Geologic Map of the Estes Park 30' x 60' Quadrangle, North-Central Colorado  

USGS Publications Warehouse

The rocks and landforms of the Estes Park 30 x 60 minute quadrangle display an exceptionally complete record of geologic history in the northern Front Range of Colorado. The Proterozoic basement rocks exposed in the core of the range preserve evidence of Paleoproterozoic marine sedimentation, volcanism, and regional soft-sediment deformation, followed by regional folding and gradational metamorphism. The metasedimentary rocks of the Estes Park quadrangle are distinct within northern Colorado for preserving the complete metamorphic zonation from low-grade chlorite-muscovite phyllites, through middle greenschist-grade rocks with sequential aluminous porphyroblasts, to partially melted gneisses that contain high-grade cordierite and garnet in the non-melted residues. Regional and textural evidence shows that the widespread metamorphism was essentially concurrent with intrusion of the Boulder Creek Granodiorite and related magmas and with the peak of deformation in the partially melted high-grade rocks. The metamorphic thermal pulse arrived later following the peak of deformation in the physically higher, cooler, low-grade terrane. Mesoproterozoic time was marked by intrusion of biotite granite in the Longs Peak-St Vrain batholith, a complex, irregular body that occupies nearly half of the core of the Front Range in this quadrangle. The magma was dry and viscous as it invaded the metamorphic rocks and caused wholesale plastic folding of the wall rock structure. Steep metamorphic foliation that resulted from the Paleoproterozoic deformations was bowed upward and re-oriented into flat-lying attitudes as the crystal-rich magma rose buoyantly and spread out in the middle crust. Magma invaded the schists and gneisses along weak foliation planes and produced a characteristic sill-upon-sill intrusive fabric, particularly in the higher parts of the batholith. Broad, open arches and swales that are defined by the flow-aligned feldspar foliation of the granite, as well as by compositional banding in the intruded and included metamorphic rocks, formed late during batholith emplacement due to rising, buoyant magma and sinking, dense wall rocks. The Longs Peak-St Vrain batholith was intruded into crust that was structurally neutral or moderately extending in an east-northeast direction. A broad zone of mylonite, the Moose Mountain shear zone, formed within the batholith during the final stages of consolidation as a result of differential buoyancy between the magma and dense wall rock, not as a result of regional tectonic deformation.

Cole, James C.; Braddock, William A.

2009-01-01

68

Geologic nozzles  

USGS Publications Warehouse

The importance of the low characteristic velocities of geologic fluids has not been widely recognized, and as a result, the importance of supercritical and supersonic flow in geological processes has generally been underestimated. The lateral blast at Mount St. Helens, Washington, propelled a gas heavily laden with dust into the atmosphere. Because of the low sound speed in this gas (about 100 m/s), the flow was internally supersonic. Old Faithful Geyser, Wyoming, is a converging-diverging nozzle in which liquid water refilling the conduit during the recharge cycle changes during eruption into a two-phase liquid-vapor mixture with a very low sound velocity. The high sound speed of liquid water determines the characteristics of harmonic tremor observed at the geyser during the recharge interval, whereas the low sound speed of the liquid-vapor mixture influences the fluid flow characteristics of the eruption. At the rapids of the Colorado River in the Grand Canyon, Arizona, the channel is constricted into the shape of a converging-diverging nozzle by the debris flows that enter from tributary canyons. Both subcritical and supercritical flow occur within the rapids. -from Author

Werner, Kieffer S.

1989-01-01

69

Habitat Alteration  

E-print Network

Habitat alteration is a change in land use or land cover that has an impact on local ecosystems. Plants and animals live in specific places that have the conditions of climate and food resources needed for survival. Habitats

unknown authors

70

Geologic Technician New Curriculum  

ERIC Educational Resources Information Center

Describes a developing two-year geologic technician program at Bakersfield College in which a student may major in five areas - geologic drafting, land and legal, geologic assistant, engineering or paleontology. (RR)

Karp, Stanley E.

1970-01-01

71

Geology of Wisconsin  

NSDL National Science Digital Library

This site contains geologic maps of Wisconsin including relief and topography maps; maps of the bedrock geology and elevation, Pleistocene geology, thickness of unconsolidated deposits, and soils; and atlases of geologic history. There is information on: rock types, Paleozoic formations, and the Pleistocene and Precambrian history of Wisconsin; how to obtain a geologic map of personal property; the Niagara Escarpment; castellated mounds; geologic field localities; and unusual weather events in Wisconsin. There is also a data table on earthquakes in Wisconsin.

Steven Dutch

1997-09-10

72

Geologic investigations  

SciTech Connect

The Climax stock is a composite granitic intrusive of Cretaceous age, composed of quartz monzonite and granodiorite, which intrudes rocks of Paleozoic and Precambrian age. Tertiary volcanic rocks, consisting of ash-flow and ash-fall tuffs, and tuffaceous sedimentary rocks overlie the sedimentary rocks and the stock. Erosion has removed much of the Tertiary volcanic rocks. Hydrothermal alteration of quartz monzonite and granodiorite is found mainly along joints and faults and varies from location to location. The Paleozoic carbonate rocks have been thermally and metasomatically altered to marble and tactite as much as 457 m (1500 ft) from the contact with the stock, although minor discontinuous metasomatic effects are noted in all rocks out to 914 m (3000 ft). Three major faults which define the Climax area structurally are the Tippinip, Boundary and Yucca faults. North of the junction of the Boundary and Yucca faults, the faults are collectively referred to as the Butte fault. The dominant joint sets and their average attitudes are N 32{degrees} W, 22{degrees} NE; N 60{degrees} W, vertical and N 35{degrees} E, vertical. Joints in outcrop are weathered and generally open, but in subsurface, the joints are commonly filled and healed with secondary minerals. 12 refs., 6 figs., 1 tab.

Orkild, P.P. [Geological Survey, Denver, CO (USA); Baldwin, M.J.; Townsend, D.R. [Fenix and Scisson, Inc., Mercury, NV (USA)

1983-12-31

73

Visible Geology - Interactive online geologic block modelling  

NASA Astrophysics Data System (ADS)

Geology is a highly visual science, and many disciplines require spatial awareness and manipulation. For example, interpreting cross-sections, geologic maps, or plotting data on a stereonet all require various levels of spatial abilities. These skills are often not focused on in undergraduate geoscience curricula and many students struggle with spatial relations, manipulations, and penetrative abilities (e.g. Titus & Horsman, 2009). A newly developed program, Visible Geology, allows for students to be introduced to many geologic concepts and spatial skills in a virtual environment. Visible Geology is a web-based, three-dimensional environment where students can create and interrogate their own geologic block models. The program begins with a blank model, users then add geologic beds (with custom thickness and color) and can add geologic deformation events like tilting, folding, and faulting. Additionally, simple intrusive dikes can be modelled, as well as unconformities. Students can also explore the interaction of geology with topography by drawing elevation contours to produce their own topographic models. Students can not only spatially manipulate their model, but can create cross-sections and boreholes to practice their visual penetrative abilities. Visible Geology is easy to access and use, with no downloads required, so it can be incorporated into current, paper-based, lab activities. Sample learning activities are being developed that target introductory and structural geology curricula with learning objectives such as relative geologic history, fault characterization, apparent dip and thickness, interference folding, and stereonet interpretation. Visible Geology provides a richly interactive, and immersive environment for students to explore geologic concepts and practice their spatial skills.; Screenshot of Visible Geology showing folding and faulting interactions on a ridge topography.

Cockett, R.

2012-12-01

74

Digital Geology of Idaho  

NSDL National Science Digital Library

This online course systematically divides Idaho geology into 15 individual teaching modules which correspond with a two-credit, 15-week classroom course. Each module covers a specific area or type of geology in the state of Idaho. Topics include geology of basement rocks, rocks and geology of the Belt Supergroup, tectonic regimes, and geologic history. There are also modules on rocks and geology of the Idaho Batholith, volcanic history and deposits of the Snake River Plain and Columbia Plateau, and Pleistocene glaciation and floods from Lakes Missoula and Bonneville. Each of the modules provides geologic maps from a recently developed Geologic Map of Idaho, produced by the Idaho Geological Survey, and most also feature fly-throughs in which geologic information is draped over topography to provide visualizations of the geology along Idaho rivers.

75

GEOLOGICAL CHARACTERISTICS  

E-print Network

CAPSULE DESCRIPTION: Ilmenite, hemo-ilmenite or titaniferous magnetite accumulations as cross-cutting lenses or dike-like bodies, Ia> ers or disseminations within anorthositiclgabbroicinoritic rocks. These deposits can be subdivided into an ilmenite subtype (anorthosite-hosted titanium-iron) and a titaniferous magnetite subtype (gabbro-anorthosite-hosted iron-titanium). TECTONIC SETTING: Commonly associated with anorthosite-gabbro-norite-monzonite (mangerite)charnockite granite (AMCG) suites that are conventionally interpreted to be anorogenic and/or extensional. Some of the iron-titanium deposits occur at continental margins related to island arc magmatism followed by an episode of erogenic compression. DEPOSITIONAL ENVIRONMENT i GEOLOGICAL SETTING: Deposits occur in intrusive complexes which typically are emplaced at deeper levels in the crust. Progressive differentiation of liquids residual from anorthosite-norite magmas leads to late stage intrusions enriched in Fe and Ti oxides and apatite. AGE OF MINERALIZATION: Mainly Mesoproterozoic (1.65 to 0.90 Ga) for the ihnenite deposits, but this may be a consequence of a particular combination of tectonic circumstances, rather than any a priori temporal control. The Fe-Ti deposits with titaniferous magnetite do not appear to be restricted in time. HOST/ASSOCIATED ROCKS: Hosted by massive, layered or zoned intrusive complexes- anorthosite, norite,

G. A. Gross; C. F. Gower; D. V. Lefebure; Commodities (byproducts) Ti

76

REMOTE SENSING GEOLOGICAL SURVEY  

E-print Network

REMOTE SENSING IN GEOLOGICAL SURVEY OF BRAZIL August/2010 Mônica Mazzini Perrotta Remote Sensing Division Head #12;SUMMARY The Geological Survey of Brazil mission The Remote Sensing Division Main remote sensing data used in CPRM geologic projects Future perspective: the Spectral Library of Geological Survey

77

History of Geology.  

ERIC Educational Resources Information Center

Discusses: (1) geologists and the history of geology; (2) American historians and the history of geology; (3) history of geology in the 1980s; (4) sources for the history of geology (bibliographies, dictionaries, encyclopedias, handbooks, periodicals, public/official histories, compilations, and books); (5) research opportunities; and (6) other…

Greene, Mott T.

1985-01-01

78

GEOLOGY (GEOL) Robinson Foundation  

E-print Network

177Geology GEOLOGY (GEOL) Robinson Foundation PROFESSOR HARBOR ASSOCIATE PROFESSORS KNAPP, CONNORS ASSISTANT PROFESSORS GREER, RAHL MAJORS BACHELOR OF SCIENCE A major in geology leading to a Bachelor of Science degree consists of 50 credits as follows: 1. Geology 160, 185, 211, 311, 330, 350

Dresden, Gregory

79

Tennessee Division of Geology  

NSDL National Science Digital Library

This is the homepage of the Geology Division of the Tennessee Department of Environment and Conservation. It provides information on the division's programs, including geologic hazards research, public service, education programs, basic and applied research on geology and mineral resources, publication of geologic information, permitting of oil and gas wells, and regulation of Tennessee's oil and gas industry. Materials include a catalog of publications, maps, geologic bulletins, and the Public Information series of pamphlets; the Geology Division Newsletter; and information on the state's mineral industry. There is also a section on the Gray Fossil Site, an unusual assemblage of fossils and sedimentary geology encountered during road construction near the town of Gray, Tenessee.

80

DNA ALTERATIONS  

EPA Science Inventory

The exposure of an organism to genotoxic chemicals may induce a cascade of genetic events. nitially, structural alterations to DNA are formed. ext, the DNA damage is processed and subsequently expressed in mutant gene products. inally, diseases result from the genetic damage. he ...

81

Vermont Geological Survey  

NSDL National Science Digital Library

The Vermont Geological Survey, also known as the Division of Geology and Mineral Resources in the Department of Environmental Conservation, conducts surveys and research relating to the geology, mineral resources and topography of the State. This site provides details about the states geology with a downloadable state geologic map and key, state rock information, gold in Vermont, fossils found in the state, bedrock mapping details, stream geomorphology, the Champlain thrust fault, earthquakes, radioactive waste and links for additional information.

82

Oklahoma Geological Survey  

NSDL National Science Digital Library

The Oklahoma Geological Survey is a state agency dedicated to geological research and public service. This site contains information on earthquakes, geographic names, general Oklahoma geology, and the mountains and water resources of the state. There are educational materials available to order, many of which are free. Geologic maps indicate rock types and ages, as well as the geologic provinces of the state. Links are provided for more resources.

83

Kentucky Geological Survey  

NSDL National Science Digital Library

The University of Kentucky maintains the Kentucky Geological Survey Web site. Visitors will find a number of educational general information pages on rocks and minerals, fossils, coal, geologic hazards, industrial minerals, maps and GIS, oil and natural gas, and water, as well as the general geology of Kentucky. Each page contains specific information, data, and research summaries from the university. The geology of Kentucky page, for example, shows a map of geologic periods and gives descriptions of the rock strata in the state, a description of its landforms, and a geological photo album of physiographic regions and points of interest.

84

Glossary of Geologic Terms  

NSDL National Science Digital Library

This page from Iowa State University presents a general glossary of geologic terms. The site would be a good reference for geology coursework. This glossary of geologic terms is based on the glossary in Earth: An Introduction to Geologic Change, by S. Judson and S.M. Richardson (Englewood Cliffs, NJ, Prentice Hall, 1995). Where possible, definitions conform generally, and in some cases specifically, to definitions given in Robert L Bates and Julia A Jackson (editors), Glossary of Geology, 3rd ed., American Geological Institute, Alexandria, Virginia, 1987.

85

Utah Geological Survey: Teaching Geology Resources  

NSDL National Science Digital Library

From Arches National Park to the towering cliffs at Castle Rock Campground, Utah has some remarkable geology on display. The Utah Geological Survey decided to draw on these fantastic "outdoor laboratories" and create a set of resources designed for science educators. While some of the resources are geared towards users in Utah, many of the sections contain helpful overviews that will help all educators remain on a steady foundation of geologic knowledge. One key area on the site is the "Earthquakes & Geologic Hazards" section. Here, visitors can find well-composed and straight forward summaries on topics like liquefaction, ground cracks, and fault lines. Moving on to the "Teacher Resources" area, visitors will find the delightful "Glad You Asked" articles and the very useful "Teacher's Corner" column which provides information on reading a stone wall and geologic stretching.

86

GSA Geologic Time Scale  

NSDL National Science Digital Library

This Geological Society of America (GSA) site contains a detailed geologic time scale as an educational resource. It may be downloaded to a larger size, and includes all Eras, Eons, Periods, Epochs and ages as well as magnetic polarity information.

1999-01-01

87

Geologic Hazards: Geomagnetism  

NSDL National Science Digital Library

Anyone researching or interested in geomagnetism will appreciate the US Geological Survey's Geologic Hazards: Geomagnetism Web site. Visitors will find research publications, various downloadable magnetic charts, models, data plots, an online calculator for magnetic fields, and more.

1997-01-01

88

Geophysics & Geology Inspected.  

ERIC Educational Resources Information Center

Summarizes findings of a recently published report of the Canadian Geoscience Council, which includes the following topics regarding college geology: facilities; teaching; undergraduate enrollments; postgraduate enrollments; geologic research; and integration of Canadian geoscience with other countries. (CS)

Neale, E. R. W.

1981-01-01

89

South Carolina Geological Survey  

NSDL National Science Digital Library

The South Carolina Geological Survey (SCGS) homepage contains information about state mapping, education and outreach programs, and recent news. For educators, there is the Earth Science education series of publications which includes presentations and page-size graphics on such topics as earthquakes, plate tectonics, geologic time, fossils, and others. Other materials include information on mineral resources, links to organizations in and about South Carolina geology, the South Carolina core repository, the Geologic Map of South Carolina, and others.

90

Geological Survey Program  

NSDL National Science Digital Library

If your research or interests lie in the geology of South Dakota, then the state's Geological Survey Program Web site is for you. Offered are online publications and maps, a geologic reference database, a lithologic logs database, digital base maps, a water quality database, and several other quality information sources worth checking out.

91

Geologic Maps and Structures Name ______________________________ Geology 100 Harbor section  

E-print Network

Geologic Maps and Structures Name ______________________________ Geology 100 ­ Harbor section The objectives of this lab are for you to learn the basic geologic structures in 3-D and to develop some facility in interpreting the nature of geologic structures from geologic maps and geologic cross sections. A big part

Harbor, David

92

Mineral formation and redox-sensitive trace elements in a near-surface hydrothermal alteration system  

SciTech Connect

A recent hydrothermal mudpool at the southwestern slope of the Rincon de la Vieja volcano in Northwest Costa Rica exhibits an argillic alteration system formed by intense interaction of sulfuric acidic fluids with wall rock materials. Detailed mineralogical analysis revealed an assemblage with kaolinite, alunite, and opal-C as the major mineral phases. Electron paramagnetic resonance spectroscopy (EPR) showed 3 different redox-sensitive cations associated with the mineral phases, Cu{sup +} is structure-bound in opal-C, whereas VO{sup 2+} and Fe{sup 3+} are located in the kaolinite structure. The location of the redox-sensitive cations in different minerals of the assemblage is indicative of different chemical conditions. The formation of the alteration products can be described schematically as a 2-step process. In a first step alunite and opal-C were precipitated in a fluid with slightly reducing conditions and a low chloride availability. The second step is characterized by a decrease in K{sup +} activity and subsequent formation of kaolinite under weakly oxidizing to oxidizing redox conditions as indicated by structure-bound VO{sup 2+} and Fe{sup 3+}. The detection of paramagnetic trace elements structure-bound in mineral phases by EPR provide direct information about the prevailing redox conditions during alteration and can, therefore, be used as additional insight into the genesis of the hydrothermal, near-surface system.

Gehring, A.U. [ETH Zurich, Schlieren (Switzerland). Inst. for Terrestrial Ecology] [ETH Zurich, Schlieren (Switzerland). Inst. for Terrestrial Ecology; [ETH Zentrum, Zurich (Switzerland). Office of Planning; Schosseler, P.M.; Weidler, P.G. [ETH Zurich (Switzerland). Inst. for Physical Chemistry] [ETH Zurich (Switzerland). Inst. for Physical Chemistry

1999-07-01

93

Geology of Kentucky  

NSDL National Science Digital Library

This website contains geologic maps of Kentucky, with a discussion of geologic time in regards to the rocks, minerals, fossils, and economic deposits found there. There are also sections that describe strata and geologic structures beneath the surface (faults, basins, and arches), the structural processes (folding and faulting) that create stratigraphic units, the geomorphology of the state, geologic information by county, a general description of geologic time, fossil, rocks, and minerals of Kentucky, and a virtual field trip through Natural Bridges State Park. Links are provided for further information.

94

Utah Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Utah Geological Survey. Materials available here include news articles and information on geologic hazards; information on places of geological interest; and popular geology topics such as earthquakes, rocks and minerals, fossils, economic resources, groundwater resources, and others. Educational resources include teaching kits, the 'Teacher's Corner' column in the survey's newsletter, and a series of 'Glad You Asked' articles on state geological topics. There is also an extensive list of free K-12 educational materials, as well as a set of curriculum materials such as activity packets, slide shows, and teachers' handbooks, which are available to order.

95

Geological Survey research 1978  

USGS Publications Warehouse

This U.S. Geological Survey activities report includes a summary of 1978 fiscal year scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral and water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

U.S. Geological Survey

1978-01-01

96

Geological Survey research 1976  

USGS Publications Warehouse

This U.S. Geological Survey activities report includes a summary of recent (1976 fiscal year) scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral resources, Water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

U.S. Geological Survey

1976-01-01

97

Virtual-Geology.Info  

NSDL National Science Digital Library

At virtual-geology.info, Roger Suthren, a professor at Oxford Brookes University, offers educational materials on geologic phenomena throughout the world. Users can take virtual field trips to study the geology of Scotland, Alaska, and France. In the Regional Geology link, visitors can view wonderful pictures of the volcanoes of Germany, Italy, France, and Greece. Educators can find images of sediments and sedimentary rocks which can be used in a variety of classroom exercises. The website supplies descriptions and additional educational links about sedimentology and environmental geology.

98

Arkansas Geological Survey  

NSDL National Science Digital Library

The Arkansas Geological Survey (AGS) homepage aims to develop and provide knowledge of the geology and hydrogeology of the State, and to stimulate development and effective management and utilization of the mineral, fossil-fuel, and water resources of Arkansas while protecting the environment. The AGC collects and disperses geologic data consisting of geologic maps, historical data concerning resources, and various datasets concerning water, fossil-fuel, and mineral resources of Arkansas. The site contains publications that can be ordered, sections about Arkansas geology, a list of mineral producers of Arkansas, and reports on mineral resources.

99

Ohio Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Ohio Geological Survey. Materials available through the site include a variety of publications, particularly the Survey's reports, bulletins, information circulars, guidebooks, and many others. There is an extensive selection of maps, including topographic maps in several scales, and downloadable geologic maps of several themes (drift thickness, bedrock geology, karst areas, glacial geology, and many others), as well as digital maps and data. The interactive maps section features online map viewers of abandoned mines, earthquake epicenters, surficial geology, geology of Lake Erie, and others. The educational resources page has links to the 'Hands On Earth' series of activities, GeoFacts (short bulletins on Ohio geological topics), nontechnical educational leaflets, field guides, and links to other publications, rock and mineral clubs, educational associations, and related websites. There is also a link to the Ohio Seismic Network, a network of seismograph stations located at colleges, universities, and other institutions that collects and disseminates information about earthquakes in Ohio.

100

Kansas Geological Survey  

NSDL National Science Digital Library

The mission of the Kansas Geological Survey, operated by the University of Kansas in connection with its research and service program, is to conduct geological studies and research and to collect, correlate, preserve, and disseminate information leading to a better understanding of the geology of Kansas, with special emphasis on natural resources of economic value, water quality and quantity, and geologic hazards. The website includes information about the High Plains and Ogallala aquifers, the Upper Arkansas corridor, the Dakota aquifer, county and state geologic maps, an online bibliography of Kansas geology, publications, a photo archive, a digital petroleum atlas, a petroleum primer for the state, gravity and magnetic maps, Hugoton project information, and details about the Hutchinson Kansas natural gas fires. The educational resources section contains a mineral information page for the state, and GeoKansas, which provides information on state geology for schools.

101

Calabozos caldera complex: geology, petrology, and geochemistry of a major silicic volcanic center and hydrothermal system in the Southern Andes  

SciTech Connect

The Calabozos caldera complex, located in the central Chilean Andes, lies at the boundary between a province of silicic and intermediate volcanism to the north and predominantly basaltic volcanism to the south. Three ash-flow sheets, Units L (0.8 Ma), V(0.30 Ma), and S(0.15 MA) of the Loma Seca Tuff represent 1000 km/sup 3/ of high-K rhyodacite and dacite magmas which erupted there. Pre-eruptive magma chambers graded from biotite-bearing rhyodacite containing 4-5 weight% H/sub 2/O with Fe-Ti oxide equilibration temperature of 800/sup 0/C in their upper reaches to amphibole-bearing dacite with 3 weight% water and temperatures between 900 and 1000/sup 0/C in deeper parts of the chamber. Fractionation of the observed phenocrysts (plagioclase, clinopyroxene, orthopyroxene, titanomagnetite and ilmenite) in model proportions is a successful model for the differentiation of the entire compositional range. Calculated fractionation paths cannot, however, account for elevated Ba, Rb, and Zr concentrations and low ..delta../sup 18/O values of the rhyodacites. These data suggest that crystal fractionation was accompanied by small amounts of contamination by assimilation of wall rocks (or partial melts of wall rocks) that had been altered previously at high temperature in a meteoric hydrothermal system. Hot springs issue mainly along resurgence-related faults. Most of the springs are interpreted as mixtures of meteoric water with a parent reservoir water that contains 400 ppm Cl at 250C. Low concentrations of both trace metals in sinter deposits and metal-complex-forming ions in the thermal waters suggest that there is no economic mineralization at shallow depths. The dilute composition of the waters, high calculated subsurface temperatures, and longevity of the magmatic and hydrothermal system make the Calabozos caldera complex an attractive geothermal target.

Grunder, A.L.

1986-01-01

102

Environmental geology of the Summitville mine, Colorado  

USGS Publications Warehouse

Although altered and mineralized rocks at Summitville mine in Colorado contain minimal amount of sulfide minerals, acid mine problems existed primarily because of the pervasive alteration of the surrounding rocks, through hydrothermal process, to highly siliceous and argillized rocks that are incapable of buffering acidic waters during weathering. The problems are compounded by the continued exposure of altered and mineralized rocks in open pit, heap leach pad and waste piles to oxygenated waters. Inadequate subsurface structural control and underground mine workings also greatly affect water quality and the location of acid mine drainage output. It is expected that with these initial results, geological studies on constrained acid-generation from ore and altered rocks will be pursued.

Gray, John E.; Coolbaugh, Mark F.; Plumlee, Geoffrey S.; Atkinson, William W.

1994-01-01

103

The Geological Society of London  

NSDL National Science Digital Library

The Geological Society of London promotes "the geosciences and the professional interests of UK geoscientists." The website offers media, geological, and society news. Researchers can find out about upcoming conferences covering a variety of geological topics as well as information on a series of journals. Everyone interested in geology can find materials on geological careers, including required education, qualifications, and funding. The website provides teaching resources on volcanoes, geologic hazards, and other geological phenomena.

104

Geologic Time: Online Edition  

NSDL National Science Digital Library

Offered by the United States Geological Survey (USGS) as a general interest publication, this site is an online edition of a text by the same name, offering a concise overview of the concepts associated with the age of the Earth. The online edition was revised in October of 1997 to reflect current thinking on this topic. Section headers are Geologic Time, Relative Time Scale, Major Divisions of Geologic Time, Index Fossils, Radiometric Time Scale, and Age of the Earth.

1997-10-09

105

Pennsylvania Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Pennsylvania Geological Survey. Users can access digital maps, data, and Geographic Information Systems (GIS), information on economic resources, and information on field mapping in the state. Classroom resources include a set of lesson plans on Pennsylvania geology; 'Rock Boxes', a set of rock samples which can be ordered; information on mineral collecting; and a series of educational publications, page-sized maps, and the 'Trail of Geology' park guide.

106

Icelandic Geology Resources  

NSDL National Science Digital Library

The main feature of this site from Hamrahlio College of Reykjavik, Iceland is an interactive geological map of Iceland showing lava flows and glaciers. Other highlights include links to related Icelandic geology pages (e.g., The Effect of Diatom Mining, Iceland's Ministry of the Environment), news sources and journals, and Icelandic geological societies (not all are in English). A recommended resource for glaciologists, volcanologists, and educators in earth science.

Douglas, Georg R.

107

Sedimentology and petroleum geology  

SciTech Connect

This book presents an introduction to sedimentology as well as petroleum geology. It integrates both subjects, which are closely related but mostly treated separately. The author covers the basic aspects of sedimentology, sedimentary geochemistry and diagenesis. Principles of stratigraphy, seismic stratigraphy and basin modelling forms the base for the part on petroleum geology. Subjects discussed include the composition of kerogen and hydrocarbons, theories of migration and trapping of hydrocarbons and properties of reservoir rocks. Introductions to well logging and production geology are given.

Bjorlykke, K.O. (Oslo Univ. (Norway))

1989-01-01

108

Geologic Maps and Structures Name ______________________________ Geology 100 Harbor section  

E-print Network

Geologic Maps and Structures Name ______________________________ Geology 100 ­ Harbor section Read Ch. 7 before you begin. The objectives of this lab are for you to learn the basic geologic structures in 3-D and to develop some facility in interpreting the nature of geologic structures from geologic

Harbor, David

109

Environmental Geology Major www.geology.pitt.edu/uprogs.html  

E-print Network

Environmental Geology Major www.geology.pitt.edu/uprogs.html Revised: 04/2004 Environmental geology in environmental geology provides the diverse skills required to work in many different employment settings issues. Within the field of geology, environmental and geotechnical jobs exist for people with BS degrees

Jiang, Huiqiang

110

Department of Geology and Geological Engineering University of Mississippi Announces  

E-print Network

Department of Geology and Geological Engineering University of Mississippi Announces Krista Pursuing a degree within the Geology & Geological Engineering department Record of financial need the University of Mississippi with a Bachelor of Science degree in geological engineering in 1982. After earning

Elsherbeni, Atef Z.

111

Structural geology report: Spent Fuel Test - Climax Nevada Test Site  

SciTech Connect

We performed underground mapping and core logging in the Climax Stock, a granitic intrusive at the Nevada Test Site, as part of a major field test to determine the feasibility of using granitic or crystalline rock for the underground storage of spent fuel from a nuclear reactor. This mapping and logging identified more than 2500 fractures, over 1500 of which were described in enough detail to allow statistical analyses and orientation studies to be performed. We identified eight joint sets, three major shear sets, and a fault zone within the Spent Fuel Test - Climax (SFT-C) portion of the Stock. Joint sets identified within the SFT-C and elsewhere in the Stock correlated well. The orientations of joint sets identified by other investigators were consistent with our findings, indicating that the joint sets are persistent and have a relatively uniform orientation throughout a major portion of the Stock. The one joint set not seen elsewhere in the Stock is healed and the wall rock is altered, implying that healed joints were not included in the mapping criteria used by other investigators. The shear sets were distinguished from the joint sets by virtue of crushed minerals, continuous clay infilling, and other evidences of shearing, and from faults by the lack of offsetting. Previous investigators working mainly in the Pile Driver Drifts identified two of the shear sets. The third set, being nearly parallel to these Drifts had not been identified previously. The fault zone identified at the far (Receiving Room) end of the project is oriented approximately N45{sup 0}E-75{sup 0}SE, similar to both the Boundary and Shaft Station Faults. We have, therefore, concluded that the Receiving Room Fault is one of a series of normal faults that occur within the Climax Stock and that are possibly related, in both age and genesis, to the Boundary Fault. 52 refs., 26 figs., 11 tabs.

Wilder, D.G.; Yow, J.L. Jr.

1984-10-01

112

Geologic Mapping Exercise  

NSDL National Science Digital Library

This exercise is designed to simulate how a basic geological investigation of a site takes place. A basic geological investigation includes familiarizing yourself with the unconsolidated sediments, rocks, structural geology, and groundwater present at your site. As part of this exercise you will have to properly identify a variety of rock types and sediments, create maps that represent data you collected at each location, and complete a basic report of your findings (optional). Once completed, this exercise should give students a basic understanding of how the various concepts used throughout the semester are applied in the real world in the form of a geological investigation.

Andrew Smith

113

Modeling Geologic Time  

NSDL National Science Digital Library

In this activity students convert major events in Earth history from years before present into scale distances. After a list of events and their scale distances have been formulated, students construct a geologic time scale on 5 meters of adding machine paper, beginning with the formation of the Earth. Students will investigate change through geologic time; design, construct and interpret a model of geologic time; relate major events in Earth history to the geologic time scale; and compare and relate the span of Earth history to events of historical time and of the human lifetime. Some sample events and their approximate relative ages are included.

Firebaugh, James

114

Geological Survey research 1981  

USGS Publications Warehouse

This U.S. Geological Survey activities report includes a summary of 1981 fiscal year scientific and economic results accompanied by a list of geologic, hydrologic, and cartographic investigations in progress. The summary of results includes: (1) Mineral, (2) Water resources, (3) Engineering geology and hydrology, (4) Regional geology, (5) Principles and processes, (6) Laboratory and field methods, (7) Topographic surveys and mapping, (8) Management of resources on public lands, (9) Land information and analysis, and (10) Investigations in other countries. Also included are lists of investigations in progress. (USGS)

U.S. Geological Survey

1982-01-01

115

Arizona Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Arizona Geological Survey. Information accessible here includes maps, information on oil, gas, and minerals in the state, back issues of the survey's newsletter, and a list of resources for public education in the state. These resources include information centers for Arizona geology and Earth Science, the survey's geology library and bibliographic database, a repository of rock cuttings and cores, and a contact for earth science education who will assist teacher groups in introducing local geology to their classes.

116

Episodic Geologic Evolution Of Mars  

NASA Astrophysics Data System (ADS)

After almost 4 years of operation in orbit, the High Resolution Stereo Camera (HRSC) Experiment on ESA's Mars Express Orbiter has covered almost 40% of the surface of Mars at a resolution of 10-20 m/pixel in color and stereo. By now, the international team of Co-Investigators has investigated much of the major structures appearing to have been shaped by volcanic, fluvial, glacial, or hydrothermal activity. Contrary to early Viking-based attempts of understanding the time-stratigraphic relationships on the martian surface by crater-counting techniques and principles of stratigraphic superposition, where most of the geological units and constructs came out as being rather old, in the range of billions of years, the new HRSC-based data tell us that Mars had continued activity throughout its whole history from more than 4 Ga ago until very recently, i.e. millions of years ago or in a few areas ongoing now. The new data, though, show episodic geological activity. There is a striking appearance of peaking of the geological activity or episodicity of resurfacing at certain times: approx. 3.5 Ga, 1 to 1.5 Ga, 300 to 600 m.y., approx. 200 m.y. ago, respectively. Even more striking is that within relatively narrow limits, the cratering ages of the different age groups fall together with the age groups of martian meteorites. The martian meteorite ages reflect both igneous events and aqueous alteration events. So do the cratering ages. There is a remarkable paucity of age occurrences in the 2-3 Ga age range in the cratering data. This corresponds to a paucity of meteorite ages in the same, even somewhat more extended age range. This appears to be a hint to either lower geologic activity in this time frame, or the covering up of more ancient activity by subsequent events <2 Ga ago, with the exception of the residues from the time >3 Ga ago (the peak at approx. 3.5 Ga) when the martian surface was thoroughly shaped at a very high level of activity by gigantic volcanic, fluvial, and glacial events which could not be completely erased by later events. The episodic behavior of martian geologic activity over time can possibly be explained by responses to the evolution of the interior of the planet that has just not reached plate tectonics. At the time of the peak of volcanic and fluvial activity around 3.7 to 3.3 Ga ago, Mars changed its environment from more basic to more acidic, and the large sulfate deposits formed. Then, rapidly, Mars fell dry on a global scale.

Neukum, G.; Co-Investigator Team

2007-12-01

117

Geology explorer: virtual geologic mapping and interpretation  

NASA Astrophysics Data System (ADS)

We are developing internet-based freeware for virtual mapping and geologic interpretation. This takes the form of a synthetic, virtual world, Planet Oit, where students are given the means and the equipment to carry out geologic investigation and interpretation as a geologist would in the field. The environment is designed to give students an authentic experience that includes elements of: (1) exploration of a spatially oriented, virtual, world; (2) practical, field oriented, expedition planning and decision-making; and (3) scientific problem solving (i.e. a "hands on" approach to mapping, geologic investigation, data acquisition, and interpretation). The game-like environment is networked, multi-player, and simulation-based. Planet Oit can be visited on the Internet at http://oit.cs.ndsu.nodak.edu/

Saini-Eidukat, Bernhardt; Schwert, Donald P.; Slator, Brian M.

2002-12-01

118

Petroleum geology of Tunisia  

Microsoft Academic Search

Recent discoveries and important oil shows have proven the existence of hydrocarbons in newly identified depocenters and reservoirs. In general, except for some areas around the producing fields, Tunisia is largely underdrilled. The national company ETAP has decided to release data and to publish a synthesis on the petroleum geology of Tunisia. The geology of Tunisia provides a fine example

P. F. Burollet; A. B. Ferjami; F. Mejri

1990-01-01

119

Radiometric Dating in Geology.  

ERIC Educational Resources Information Center

Described are several aspects and methods of quantitatively measuring geologic time using a constant-rate natural process of radioactive decay. Topics include half lives and decay constants, radiogenic growth, potassium-argon dating, rubidium-strontium dating, and the role of geochronology in support of geological exploration. (DS)

Pankhurst, R. J.

1980-01-01

120

Geologic Time Online Edition  

NSDL National Science Digital Library

This tutorial will help students learn and understand the concepts of geologic time and the age of the Earth. They will investigate the geologic time scale and learn about the use of index fossils and radiometric dating to determine the age of rock formations and fossils.

121

Geologic time scale bookmark  

USGS Publications Warehouse

This bookmark, designed for use with U.S. Geological Survey activities at the 2nd USA Science and Engineering Festival (April 26–29, 2012), is adapted from the more detailed Fact Sheet 2010–3059 "Divisions of Geologic Time." The information that it presents is widely sought by educators and students.

U.S. Geological Survey

2012-01-01

122

Paleogeography Through Geologic Time  

NSDL National Science Digital Library

This website contains paleogeographic and plate tectonic reconstructions organized by geologic period. Users select a geologic period, and receive a summary of the major events that occurred during that period, a paleogeographic map, tectonics and sedimentation of the North Atlantic region, and global tectonic features from that time.

Blakey, Ronald

123

Geological Map Problem  

NSDL National Science Digital Library

This is a lab activity that is designed to help introductory, non-science majors integrate their geological knowledge near the end of the course. In this activity, students work in self-selected groups of up to four per group on the history of a sketch geological map.

Robert Filson

124

People and Geology.  

ERIC Educational Resources Information Center

Provides background information on the many natural resources we extract from the earth's crust, including metals, graphite, and other minerals, as well as fossil fuels. Contains teaching activities such as a geologic scavenger hunt, a geology chronology, and the recycling of aluminum. Includes a reproducible handout for the activity on aluminum.…

Naturescope, 1987

1987-01-01

125

Layer Cake Geology  

NSDL National Science Digital Library

This classroom activity uses a cake to demonstrate geologic processes and introduce geologic terms. Students will learn how folds and faults occur, recognize the difference in behavior between brittle and ductile rocks, and attempt to predict structures likely to result from application of various forces to layered rocks. They will also attempt to interpret 'core samples' to determine subsurface rock structure.

Wagner, John

126

Glossary of geology  

SciTech Connect

This third edition of the Glossary of Geology contains approximately 37,000 terms, or 1,000 more than the second edition. New entries are especially numerous in the fields of carbonate sedimentology, hydrogeology, marine geology, mineralogy, ore deposits, plate tectonics, snow and ice, and stratigraphic nomenclature. Many of the definitions provide background information.

Bates, R.L.; Jackson, J.A.

1987-01-01

127

Advances in Planetary Geology  

NASA Technical Reports Server (NTRS)

Advances in Planetary Geology is a new series intended to serve the planetary geology community with a form for quick and thorough communications. There are no set lists of acceptable topics or formats, and submitted manuscripts will not undergo a formal review. All submissions should be in a camera ready form, preferably spaced, and submitted to the editor.

Woronow, A. (editor)

1982-01-01

128

California Geological Survey - Landslides  

NSDL National Science Digital Library

This page from the CA Geological Survey (CGS) presents information on landslides as well as maps and products of various past and present CGS programs to map and respond to landslides in the state of California, including the Forest and Watershed Geology Program, the Seismic Hazards Zonation Program, the Caltrans Highway Corridor Mapping project, and the Landslide Map Index.

Survey, California G.

129

BS in GEOLOGY: Environmental Geology Emphasis (694029) MAP Sheet Department of Geological Sciences  

E-print Network

BS in GEOLOGY: Environmental Geology Emphasis (694029) MAP Sheet Department of Geological Sciences with environmental degradation and natural geologic hazards has led to a demand for geologists who are both well grounded in the fundamentals of the science of geology and specifically prepared to address environmental

Seamons, Kent E.

130

British Geological Survey: Learning  

NSDL National Science Digital Library

The British Geological Survey (BGS) has a wealth of information about the earth sciences, and they are quite willing to share it with others. This page contains information and resources for anyone interested in geology for educational or leisure purposes, and it is contained with four sections. First up is "Popular geology", which includes "Britain beneath our feet", an interactive atlas of geology, resources, and land quality. This section also contains graphics about climate change and earthquakes. The second section is titled "Educational resources". Here visitors can ask scientists at the BGS specific questions and they can also download several free posters. The third section is called "Educational news and events" and it features upcoming events at the BGS and links to their free magazine, "Earthwise". The site is rounded out by the fourth section titled "From the BGS Archives". Here visitors can view historic geological photographs and also view field sketches and watercolors by Alexander Henry Green, the celebrated Victorian geologist.

131

Field Geology/Processes  

NASA Technical Reports Server (NTRS)

The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

1996-01-01

132

Wyoming State Geological Survey  

NSDL National Science Digital Library

This agency's mission is to study, examine, and seek an understanding of the geology, mineral resources, and physical features of the State; to prepare, publish, and distribute reports and maps of Wyoming's geology, mineral resources, and physical features; and to provide information, advice, and services related to the geology, mineral resources, and physical features of the State. This site contains details and reports about metals in Wyoming, earthquakes and other hazards, coal, industrial minerals, uranium, oil and gas. The field trip section contains details about various areas to visit with students and gives a general geologic description. There is also a searchable bibliography with publications about Wyoming geology. Links are provided for additional resources.

133

77 FR 19032 - Geological Survey  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF THE INTERIOR Geological Survey Announcement of National Geospatial...Advisory Committee Meeting AGENCY: U.S. Geological Survey, Interior. ACTION: Notice...contacting Arista Maher at the U.S. Geological Survey (703-648-6283,...

2012-03-29

134

Essential Elements of Geologic Reports.  

ERIC Educational Resources Information Center

Described is a report outline for geologic reports. Essential elements include title; abstract; introduction; stratigraphy; petrography; geochemistry; petrology; geophysics; structural geology; geologic history; modeling; economics; conclusions; and recommendations. (Author/CW)

Webb, Elmer James

1988-01-01

135

Principles of Historical Geology Geology 331  

E-print Network

in Biostratigraphy Section #12;Principle of Superposition In any undeformed sequence of sedimentary rocks, each bed of a valley can be correlated. · This principle is used to trace coal seams from one mountain to the next;Igneous dikes in black, granite in pink #12;#12;Can you interpret the sequence of geologic events using

Kammer, Thomas

136

Kentucky Geological Survey  

NSDL National Science Digital Library

In 1996 the Education Committee of the Kentucky Geological Survey, in conjunction with the Kentucky Society of Professional Geologists, established the Earth Science Education Network (ESEN). The network provided a group of geologists who served as resource persons for teachers, but has now been expanded to provide resources from around the globe. While primarily focusing on the geology of Kentucky, many of the online resources are applicable for educators throughout the U.S. There are links to Earth science topics and important websites, handouts and instructions for classroom demonstrations and activities, and also interesting information about Kentucky geology and publications.

137

What is Geologic Time?  

NSDL National Science Digital Library

This webpage of the National Park Service (NPS) and United States Geological Survey (USGS) discusses geologic time and what it represents. Beginning about 4.6 billion years ago and ending in the present day, this site exhibits (to scale) the various eras, periods, eons, and epochs of Earth's history with a downloadable geologic time scale available. Links provide maps of what the Earth looked like at various times in its history, as well as a description of how scientists developed the time scale and how they know the age of the Earth.

138

Formation evaluation: Geological procedures  

SciTech Connect

This volume goes beyond a discussion of petroleum geology and the techniques of hydrocarbon (oil and gas) logging as a reservoir evaluation tool. It provides the logging geologist with a review of geological techniques and classification systems that will ensure the maximum development of communicable geological information. Contents include: 1. Introduction--cuttings recovery, cutting sampling, core sampling, rock classification; 2. Detrital rocks--classification, description; 3. Carbonate rocks--classification, description; 4. Chemical rocks-introduction, siliceous rocks, ferruginous rocks, aluminous rocks, phosphatic rocks, aluminous rocks, carbonaceous rocks; 5. Igneous and metamorpbic rocks; Appendix; References and Index.

Whittaker, A.

1985-01-01

139

Journal of Geology  

NSDL National Science Digital Library

From the University of Chicago Press's Journals Division, the Journal of Geology is currently available online free of charge (note: subscription fees may soon apply, but no initiation date is provided). This first-rate technical journal, which publishes "research and theory in geophysics, geochemistry, sedimentology, geomorphology, petrology, plate tectonics, volcanology, structural geology, mineralogy, and planetary sciences" has been in print form since 1893. All of the 1999 issues of the Journal of Geology electronic edition are available here. Internet users can access full-text articles with internal links to references and figures (html, .pdf. .ps).

140

Web Geologic Time Scale  

NSDL National Science Digital Library

The University of California-Berkeley Museum of Paleontology (last mentioned in the June 16, 1995 Scout Report) has recently updated its Web Geologic Time Scale, an online feature that helps users learn about the geologic timeline and explore related museum exhibits. The familiar geologic timeline appears on the main page of the Web site, with hypertext links for each division of time. Every page of the Web Geologic Time Machine site is liberally sprinkled with links to related UCMP Web pages; think of it as a portal to all online information available from the museum. Altogether, this Web site provides a well-organized and comprehensive resource for learning how the planet has changed over time, and would be a great addition to earth or life sciences classroom material for a broad range of grades.

1994-01-01

141

Interactive Geologic Timeline Activity  

NSDL National Science Digital Library

In this learning activity, students use a web-based geologic timeline to examine temperature, CO2 concentration, and ice cover data to investigate how climate has changed during the last 715 million years.

University, Environmental L.

142

Scaling the Geologic Past  

ERIC Educational Resources Information Center

Describes construction of a Geologic Time Scale on a 100 foot roll of paper and suggests activities concerning its use. Includes information about fossils and suggestions for conducting a fossil field trip with students. (BR)

Gerritts, Mary

1975-01-01

143

Comprehending Geologic Time  

NSDL National Science Digital Library

This online calculator helps students understand the classic analogy of relating the geologic time scale to a yard stick. It will help reinforce the concept of the briefness of human history relative to the age of the Earth.

144

North Dakota Geological Survey  

NSDL National Science Digital Library

This is the homepage of the North Dakota Geological Survey. Site materials include information on the state's oil, gas and coal resources, maps, publications, and regulations. The paleontology page features educational articles, information on fossil collecting, articles about fossil exhibits, and information on the state fossil collection. The state GIS hub creates and distributes digital spatial data that conforms to national mapping standards. The teaching tools page includes illustrations and descriptions of rocks and minerals found in the state, as well as information on meteorites and newsletter articles about teaching North Dakota geology. There are also links to landslide maps, surficial geology maps, and links to other survey publications such as reports, bulletins, field studies, other geological and topographic maps, and information on groundwater resources.

145

Economic Geology (Oil & Gas)  

ERIC Educational Resources Information Center

Briefly reviews the worldwide developments in petroleum geology in 1971, including exploration, new fields, and oil production. This report is condensed from the October Bulletin of the American Association of Petroleum Geologists. (PR)

Geotimes, 1972

1972-01-01

146

Photos of structural geology  

NSDL National Science Digital Library

This page contains four categories of structural geology photos: brittle structures, ductile structures, active tectonics, and unconformities. All photos are freely downloadable and are at resolutions sufficient for power point.

Miller, Marli

147

Reconstructing the Geologic Timeline.  

ERIC Educational Resources Information Center

Reports on the use of a non-traditional approach to constructing a geological timeline that allows students to manipulate data, explore their understanding, and confront misconceptions. Lists possible steps to use in engaging students in this constructivist activity. (DDR)

Hemler, Deb; Repine, Tom

2002-01-01

148

Bedrock Geology Mapping Exercise  

NSDL National Science Digital Library

This field mapping and map-making exercise is a capstone project for a course on Geological Maps. Over a weekend (~12 hours of field work), students collect lithologic and structural data from outcrops scattered over a one square mile area. Back in the classroom, students digitally compile their field data (outcrop, structure measurements, traverse locations) into ArcMAP. They infer geologic linework (faults and contacts) and units from this data in ArcMAP and then export these data layers into Illustrator. In Illustrator, they add ancillary map components (a cross section, description of map units, correlation diagram, map symbol legend,...) to create a final map at a 1:10,000 scale. Their maps are printed out on 11"x17" paper and saved as a pdf file. This exercise helps the students to appreciate how field data is collected and how these geologic facts are interpretively organized into a four-dimensional picture that is a geologic map.

Miller, Jim

149

USGS Geologic Hazards  

NSDL National Science Digital Library

The Geologic Hazards section of the US Geological Survey (USGS) conducts research into the causes of geological phenomena such as landslides and earthquakes. The homepage connects visitors to the Geologic Hazards team's three main areas of endeavor. Geomagnetism provides links to the National Geomagnetic Information Center; Magnetic Observatories, Models, and Charts; and the Geomagnetic Information Node, which receives geomagnetic observatory data from around the world. The Landslide group studies the "causes and mechanisms of ground failure" to prevent "long-term losses and casualties." Their section provides links to the program and information center, publications, events, and current projects. The Earthquakes department hosts a wealth of information, including neotectonics, engineering seismology, and paleoseismology. Interactive maps are also provided.

150

Geologic evolution of Arizona  

SciTech Connect

Seven years in the making, the 35 papers in this volume summarize the stratigraphic, structural, and tectonic evolution of Arizona from Precambrian through Quaternary time. Intended as a compendium of current knowledge of Arizona geology, the papers synthesize previous work with new data, ideas, and concepts as well as identifying unresolved problems for future research. Emphasis is placed on the geologic evolution of the state as a whole rather than specific local areas. The papers are organized in terms of geologic eras: Proterozoic, Paleozoic, Mesozoic, and Cenozoic. The concluding section offers topical studies in the areas of geophysics, industrial minerals, uranium, oil and gas, geothermal resources, hydrogeology, and environmental geology. California readers will find much of interest in this research volume because many of the tectonic processes that formed Arizona also affected the development of this state.

Penny, J.P.; Reynolds, S.J. (eds.)

1989-01-01

151

Geologic exploration of Mars  

NASA Technical Reports Server (NTRS)

The scientific objectives and methods involved in a geologic exploration of Mars from a manned outpost are discussed. The constraints on outpost activities imposed by the limited crew size, limited amount of time available for science, the limited diversity of scientific expertise, and the competition between scientific disciplines are addressed. Three examples of possible outpost locations are examined: the Olympus Mons aureole, Mangala Valles/Daedalia Planum, and Candor Chasma. The geologic work that could be done at each site is pointed out.

Plescia, J. B.

1990-01-01

152

Understanding Geologic Time  

NSDL National Science Digital Library

This informational tour offers students a basic understanding of geologic time, the evidence for events in the history of the Earth, relative and absolute dating techniques, and the significance of the Geologic Time Scale. Students move at a self-selected pace by answering questions correctly as they go. The teacher's guide contains all the details needed to use this computer activity, including handouts, a lesson plan, and assessment materials.

Scotchmoor, Judy

153

Geologic Time Discussion Analogies  

NSDL National Science Digital Library

The slides provide a fun way of discussing the immensity of geologic time and help to grasp the age of the earth, the time gaps between major geologic events, and the relative minuteness of humans time on earth. After the discussion with the class, students are given opportunity to develop their own analogies using "everyday" things (other than the calendar and money examples used in this activity).

Noah Fay

154

Johnston Geology Museum  

NSDL National Science Digital Library

The Johnston Geology Museum is part of the Emporia State University Earth Science Department. There is an online virtual tour of the collection which includes a Cretaceous mosasaur, a giant ground sloth, mastodon bones and tusk, brachiopods, Paleozoic corals, sedimentary structures, minerals and crystals. The Museum contains geological specimens predominantly from Kansas, and include the world famous Hamilton Quarry Fossil Assemblage, the Tri-State Mining Display, petrified tree stumps, and the Hawkins and the Calkins Indian Artifact Collections.

2011-07-07

155

Oahu Geology Field Exercises  

NSDL National Science Digital Library

Three field guides are available to sites of geologic interest on Oahu. One is a visit to a landslide occurring in a neighborhood; another focuses on developing observational skills and determining the sequence of geologic events evident in a stratigraphic section; a third examines features associated with formation of a volcanic tuff ring. The worksheets are designed for teachers to implement as-is or modify for their classes.

156

Interpreting Geologic Sections  

NSDL National Science Digital Library

Athro, Limited is a for-profit corporation that publishes high school and college level biology, earth science, and geology course supplements and independent learning materials on the Web. This site provides instruction in interpreting the order of events in three hypothetical and one real geological section. For each section there is a list of events and an animation of the history of the section once the student has decided on the order of events.

Paul Morris

157

Geology and Human Health  

NSDL National Science Digital Library

This site contains a variety of educational and supporting materials for faculty teaching in the emerging field of geology and human health. You will find links to internet resources, books, teaching activities, and a group email list, as well as posters, presentations and discussions from the spring 2004 workshop on Geology and Human Health. These resources reflect the contributions of faculty members from across the country and the collections will continue to grow as materials are developed.

158

Illustrated Glossary of Geologic Terms  

NSDL National Science Digital Library

Provided by the Geology Department at Iowa State University, this handy illustrated glossary of geological terms is an excellent quick reference resource for students. Continuously upgraded with links to illustrations and text, this geological lexicon is based on the glossary in the textbook Earth: An Introduction to Geological Change by S. Judson and S.M. Richardson. Alphabetical tabs and internal links to related terms let users move quickly around this useful aid for geology students.

159

A geological explanation for intraplate earthquake clustering complexity: The zeolite-bearing fault/fracture networks in the Adamello Massif (Southern Italian Alps)  

NASA Astrophysics Data System (ADS)

Interconnected networks of faults and veins filled with hydrothermal minerals such as zeolite are widespread in many orogenic terrains. These fractures commonly form at relatively low temperatures (e.g. <200 °C) late in the tectonic history and represent significant phases of fluid flow and mineralisation during exhumation. Zeolite-bearing fractures spatially associated with the Gole Larghe Fault Zone in the Southern Italian Alps are preserved along an interconnected network of variably orientated pre-existing structures. They show evidence of repeated episodes of hydraulic tensile fracturing and small magnitude (total offsets <5 m) shear displacements. We use geological observations and Coulomb stress modelling to propose that repeated seismogenic rupturing of larger offset faults led to local stress transfer and reactivation of widely distributed smaller pre-existing structures in the wall rocks. The differing orientations of the pre-existing features within what is assumed to have been a single regional stress field led to the simultaneous development of reverse, strike-slip and extensional faults. The kinematic diversity and cyclic nature of the hydraulically-assisted deformation suggest that the mineralised fracture systems represent a geological manifestation of intraplate micro-earthquake clusters associated with fluid migration episodes in the upper crust. Our observations highlight the role of crustal fluids and structural reactivation during earthquakes.

Dempsey, E. D.; Holdsworth, R. E.; Imber, J.; Bistacchi, A.; Di Toro, G.

2014-09-01

160

Minnesota Geological Survey  

NSDL National Science Digital Library

The Minnesota Geological Survey (MGS) was established in 1872 as part of the University of Minnesota. The function of the MGS is to serve "the people of Minnesota by providing systematic geoscience information to support stewardship of water, land, and mineral resources." This website from the Digital Conservancy at the University of Minnesota provides access to all of items published by the MGS. The items are contained within the Collections area, and visitors will find headings here such as "Geology of Minnesota Parks," "County Atlas Series," and the "Bulletin of the Minnesota Geological and Natural History Survey." First-time visitors can check out the Recent Submissions area on the right-hand side of the page to look over some new findings, including hydrogeological maps of different counties around the state. One item that should not be missed is the "Geology of Minnesota: A Centennial Volume" from 1972. It's a tremendous volume and one that cannot be ignored by students of the physical landscape and geological history of the state.

2012-09-21

161

Minnesota Geological Survey  

NSDL National Science Digital Library

Established in 1872 by the State of Minnesota as part of the University of Minnesota, the Minnesota Geological Survey (MGS) serves the people of Minnesota by providing systematic geoscience information to support the stewardship of water, land, and mineral resources. This rather lovely digital collection brings together a record of all items published by the MGS since its creation. Here, visitors will find documents, reports, maps, and GIS data for online viewing or downloading as well. The thematic collections here include the Aeromagnetic Map Series, the annual reports of the Minnesota Geological and Natural History Survey, and the wonderful county atlas series. Visitors with a penchant for geology, natural history, and geography will find much to enjoy here.

162

Geologic map of Mars  

USGS Publications Warehouse

This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and interpretation in support of geologic mapping. In particular, the precise topographic mapping now available has enabled consistent morphologic portrayal of the surface for global mapping (whereas previously used visual-range image bases were less effective, because they combined morphologic and albedo information and, locally, atmospheric haze). Also, thermal infrared image bases used for this map tended to be less affected by atmospheric haze and thus are reliable for analysis of surface morphology and texture at even higher resolution than the topographic products.

Tanaka, Kenneth L.; Skinner, James A.; Dohm, James M.; Irwin, Rossman P., III; Kolb, Eric J.; Fortezzo, Corey M.; Platz, Thomas; Michael, Gregory G.; Hare, Trent M.

2014-01-01

163

Sedimentology and petroleum geology  

SciTech Connect

In this introduction to sedimentology and petroleum geology the subjects, which are closely related but mostly treated separately, are integrated. The first part covers the basic aspects of sedimentology, sedimentary geochemistry and diagenesis, including brief discussions of flow in rivers and channels, types of sediment transport, lake and river deposits, deltas (river-dominated, tide-dominated, and wave-dominated) and the water budget. Principles of stratigraphy, seismic stratigraphy and basin modeling form the basis for the last part on petroleum geology. Here subjects include the composition of kerogen and hydrocarbons, theories of migration and trapping of hydrocarbons and properties of reservoir rocks. Finally, short introductions to well logging and production geology are given.

Bjorlykke, K.

1989-01-01

164

Global sedimentary geology program  

SciTech Connect

The Society of Economic Paleontologists and Mineralogists, in collaboration with the International Association of Sedimentologists and the International Union of Geological Sciences Committee on Sedimentology, is developing a new international study under the provisional title of Global Sedimentary Geology Program (GSGP). Initially, three research themes are being considered: (1) event stratigraphy-the documentation of examples of mass extinctions, eustatic fluctuations in sea level, major episodes of volcanisms, and changes in ocean composition; (2) facies models in time and space-an expansion of the existing data base of examples of facies models (e.G., deltas, fluvial deposits, and submarine fans) and global-scale study of the persistence of facies at various times in geologic history; and (3) sedimentary indices of paleogeography and tectonics-the use of depositional facies and faunas in paleogeography and in assessing the timing, locus, and characteristics of tectonism. Plans are being developed to organize pilot projects in each of these themes.

Ginsburg, R.N.; Clifton, H.E.; Weimer, R.J.

1986-07-01

165

Geology of Io  

NASA Technical Reports Server (NTRS)

Geologic mapping of the Jovian satellite Io has been completed at 1:15,000,000 scale for an area lying between +40 and -90 deg latitude and 230 and 45 deg longitude, which includes portions of the Ruwa Patera quadrangle (Ji2) and the Lerna Region (Ji4) and the westernmost section of the Colchis Region (Ji3). Image resolution in the mapped area is commonly 0.5 to 2 km/pxl. High resolution areas (less than .5 km/pxl) are located near the south pole (Lerna Region) and in eastern Ruwa Patera quadrangle. Geologic maps for the Ruwa Patera quadrangle (Ji2) and the Lerna Region (Ji4) have been produced at 1:5,000,000 scale. The present effort reexamines the previously mapped areas and synthesizes the geology of Io on a global scale.

Greeley, R.; Craddock, R. A.; Crown, D. A.; Leshin, L. A.; Schaber, G. G.

1987-01-01

166

Effect of Hydrothermal Alteration on Rock Properties in Active Geothermal Setting  

NASA Astrophysics Data System (ADS)

Hydrothermal alteration records the physical-chemical changes of rock and mineral phases caused by the interaction of hot fluids and wall rock, which can impact effective permeability, porosity, thermal parameters, rock strength and other rock properties. In this project, an experimental approach has been used to investigate the effects of hydrothermal alteration on rock properties. A rock property database of contrastingly altered rock types and intensities has been established. The database details horizontal and vertical permeability, porosity, density, thermal conductivity and thermal heat capacity for ~300 drill core samples from wells THM12, THM13, THM14, THM17, THM18, THM22 and TH18 in the Wairakei-Tauhara geothermal system (New Zealand), which has been compared with observed hydrothermal alteration type, rank and intensity obtained from XRD analysis and optical microscopy. Samples were selected from clay-altered tuff and intercalated siltstones of the Huka Falls Formation, which acts as a cap rock at Wairakei-Tauhara, and tuffaceous sandstones of the Waiora Formation, which is a primary reservoir-hosting unit for lateral and vertical fluid flows in the geothermal system. The Huka Falls Formation exhibits argillic-type alteration of varying intensity, while underlying Waiora Formations exhibits argillic- and propylithic-type alteration. We plan to use a tempered triaxial test cell at hydrothermal temperatures (up to 200°C) and pressures typical of geothermal conditions, to simulate hot (thermal) fluid percolation through the rock matrix of an inferred "reservoir". Compressibility data will be obtained under a range of operating (simulation reservoir) conditions, in a series of multiple week to month-long experiments that will monitor change in permeability and rock strength accompanying advancing hydrothermal alteration intensity caused by the hot brine interacting with the rock matrix. We suggest, our work will provide new baseline information concerning fluid-rock interaction processes in geothermal reservoirs, and their effects on rock properties, that will aid improved understanding of the evolution of high-temperature geothermal systems, provide constraints to parameterization of reservoir models and assist future well planning and design through prediction of rock properties in the context of drilling strategies.

Mikisek, P.; Bignall, G.; Sepulveda, F.; Sass, I.

2012-04-01

167

Pattern Alteration: Shoulder Slope  

E-print Network

Determining the amount of alteration needed for square or sloping shoulders depends on observation and past experience in fitting home-sewn and purchased garments. This publication gives alteration instructions for basic bodices and kimono style...

2006-05-05

168

Principles of isotope geology  

Microsoft Academic Search

Discussions of methods of isotope dating using Rb-Sr, K-Ar, ⁴°Ar\\/³⁹Ar, Re-Os, Lu-Hf, K-Ca, U, Tb-Pb, ¹⁴C, common lead, S,O,H, fission track, and U-series disequilibrium are included in respective chapters. Introductory chapters discussing the basics of isotope geology, atomic structure, decay mechanisms and mass spectrometry are included along with two appendices; the geological time scale for the Phanerzoic and a fitting

G Faure

1977-01-01

169

Geological Survey of Alabama  

NSDL National Science Digital Library

This is the homepage of the Geological Survey of Alabama (GSA), a data gathering and research agency that explores and evaluates the mineral, water, energy, biological, and other natural resources of the State of Alabama and conducts basic and applied research in these fields as a public service to citizens of the State. The GSA homepage contains a geologic map of Alabama; information on GSA news and events; GSA publications; GIS data and maps; an Ask the Geologist, Hydrogeologist and Biologist link; and a Geospatial Data Clearinghouse.

170

BGS Geological Timechart  

NSDL National Science Digital Library

This is the geological time scale developed by the British Geological Survey. The principal chart is the Phanerozoic (Cambrian to Quaternary) timescale. The names of the individual periods are live links, each one leading to a chart showing the subdivisions of each period into epochs and ages. The Proterozoic and Neoproterozoic sections are also linked to further subdivisions into eras and periods. Dates are in millions of years before present. A guide on the front page describes the bases for the divisions used on this time scale and how to use it, and a downloadable version is also provided.

171

Understanding Geological Time  

NSDL National Science Digital Library

In this classroom activity, middle school students gain an understanding of geologic time. The activity opens with background information for teachers about carbon and radiometric dating. In a classroom discussion, students share what they know about geologic time. Then, working in small groups responsible for different eras, students create a timeline for their assigned era by conducting library and Internet research. The activity concludes by having students review all the timelines to compare how long humans have been on the Earth to the length of time dinosaurs inhabited the planet.

172

A Formative Assessment of Geologic Time for High School Earth Science Students  

NSDL National Science Digital Library

Earth science courses typically include the concept of geological time. The authors of this study attempt to move past traditional assessment practices and develop a formative assessment of students' understanding of the construction of the geologic time scale and how it is interpreted. Through this approach students are challenged to conceptualize the geologic time scale by comparing it to a student-produced time scale for an older adult's life. This formative assessment allows the teacher to alter instruction based on students' feedback in order to maximize student understanding of geologic time.

2004-05-01

173

Life on Guam: Geology.  

ERIC Educational Resources Information Center

This unit is part of a series of materials produced by a project to develop locally applicable class, lab, and field materials in ecology and social studies for Guam junior and senior high schools. While the materials were designed for Guam, they can be adapted to other localities. This unit is designed to acquaint the students with the geology of…

Elkins, Gail

174

Geology by Lightplane  

NSDL National Science Digital Library

This site is a collection of aerial images of US geological features. Detailed 2000-pixel-wide JPEG versions of these photos (averaging 1MB in size and suitable for video projection or for slides) can be down-loaded from an FTP site. There are also text captions for the photographs.

Maher, Louis J.; Wisconsin-Madison, The D.

175

Marine Environmental Geology  

NSDL National Science Digital Library

This course is an introduction to the aspects of marine geology and oceanography that affect the environment and marine resources. Service-learning is an essential component of how students learn about the earth. We deliver part of the content of this course by arranging for students to solve a problem with a local community partner.

Course taught by Prof. Ed Laine, Bowdoin College (edlaine@bowdoin.edu) and Cathryn Field, Lab Instructor (cfield@bowdoin.edu). Example compiled by Suzanne Savanick, Science Education Resource Center (ssavanic@carleton.edu).

176

Layer Cake Geology  

NSDL National Science Digital Library

This activity provides young students with a relevant model (a layer cake) to help them understand concepts about sedimentary rock layers (such as the Law of Superposition), correlation of the rock record with geologic time and relative ages of rocks and fossils.

Molly Ward

177

Public perceptions of geology  

NASA Astrophysics Data System (ADS)

Geological issues are increasingly intruding on the everyday lives of ordinary people. Whether it be onshore exploration and extraction of oil and gas, deep injection of water for geothermal power or underground storage of carbon dioxide and radioactive waste, many communities across Europe are being faced with potentially contested geological activity under their backyard. As well as being able to communicate the technical aspects of such work, geoscience professionals also need to appreciate that for most people the subsurface is an unfamiliar realm. In order to engage communities and individuals in effective dialogue about geological activities, an appreciation of what 'the public' already know and what they want to know is needed, but this is a subject that is in its infancy. In an attempt to provide insight into these key issues, this study examines the concerns the public have, relating to geology, by constructing 'Mental Models' of people's perceptions of the subsurface. General recommendations for public engagement strategies will be presented based on the results of selected case studies; specifically expert and non-expert mental models for communities in the south-west of England.

Gibson, Hazel; Stewart, Iain; Anderson, Mark; Pahl, Sabine; Stokes, Alison

2014-05-01

178

Geologic Data Systems  

USGS Multimedia Gallery

Several of the systems used for viewing and storing geologic data as it's captured from the onboard instrumentation. The USGS returned from a seafloor data mapping mission offshore of the Delmarva Peninsula (Ocean City, MD) on July 25th, 2014. The data collected is foundational to our continued und...

179

Advances in planetary geology  

NASA Technical Reports Server (NTRS)

A wide variety of topics on planetary geology are presented. Subjects include stratigraphy and geomorphology of Copernicus, the Mamers valle region, and other selected regions of Mars and the Moon. Crater density and distribution are discussed for Callisto and the lunar surface. Spectroscopic analysis is described for Europa and Ganymede.

1984-01-01

180

Glacial Geology of Wisconsin.  

ERIC Educational Resources Information Center

This publication is a teacher's resource and guidebook for the presentation of the three filmstrips in the "Glacial Geology of Wisconsin" series. The first filmstrip is subtitled, "Evidence of the Glaciers," the second "How the Glaciers Reshaped the Landscape," and the third "Fossils of the Ice Age." Included are a list of objectives, an outline…

Madison Public Schools, WI.

181

Dinosaur Paleobiology Geology 331  

E-print Network

Dinosaur Paleobiology Geology 331 Paleontology #12;Dinosaurs are popular with the public #12;Jack Horner, Montana State Univ. #12;Field Work in Montana #12;A dinosaur "drumstick" in its field jacket. #12;Abundant vascular canals in dinosaur bone support the warm- blooded theory #12;Thin section of dinosaur

Kammer, Thomas

182

Mass Extinctions Geology 331  

E-print Network

groups · Devonian ­ about 40% of marine genera including all stromatoporoids, all shallow water corals;Stromatoporoids and Corals sarv.gi.ee/geology/photos.html #12;Rugose Corals #12;Victims · Permian ­ about 50 brachiopods ­ All rugose and tabulate corals ­ All remaining trilobites ­ Nearly all crinoids ­ Nearly all

Kammer, Thomas

183

Geological impacts on nutrition  

Technology Transfer Automated Retrieval System (TEKTRAN)

This chapter reviews the nutritional roles of mineral elements, as part of a volume on health implications of geology. The chapter addresses the absorption and post-absorptive utilization of the nutritionally essential minerals, including their physiological functions and quantitative requirements....

184

American Geological Institute Homepage  

NSDL National Science Digital Library

This is the homepage of the American Geological Institute (AGI). Visitors can access information about geoscience education, public policy, environmental geoscience, careers in geoscience, publications, news articles, and events. Materials presented here include databases, curriculum materials, legislation and appropriations information, and an image bank.

185

Briefing on geological sequestration  

EPA Science Inventory

Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media ? primarily saline formations, depleted or nearly depleted oil and gas...

186

Geology of Crater Lake  

NSDL National Science Digital Library

The Geology of Crater Lake is a resource for an introductory course on the geology of Mount Mazama and the Crater Lake caldera. The actual course consists of two evening presentations and a one-day field trip. The presentations outline the mountain's geologic setting, eruptive history, and potential hazards. The field trip affords an opportunity to examine volcanic and glacial features around the caldera rim and to explore one of the most spectacular lakes in the world. Upon successful completion of this course a student will be capable of the following: to describe the geologic setting of Mount Mazama and the other Cascade volcanoes; to identify andesite, dacite, and basalt and explain how the compositions of the lavas that form these rocks influence their eruptive characters; and to outline the major types of hazards that future eruptions of Mount Mazama may pose to regional communities. Along with a course syllabus, a bibliography and related links are available. Those registered for the course can visit the Gradebook to view their marks.

Hirt, William

187

Soviet geology, 1976  

Microsoft Academic Search

The geological history of the Jurassic period shows that the most abrupt change in physiogeographical, and particularly in climatic, conditions occured not at its lower or upper limit but at the boundary between the middle and late epochs. This is shown especially clearly by a study of the lacustral and continental sediments which form such a significant feature of the

V. A. Vakhrameyev

1976-01-01

188

IDAHO FLUVIAL GEOLOGY  

EPA Science Inventory

Restricted availability. Major Attributes: Polygons described by geologic type codes & descriptions. May be incorporated into maps at the state/county/basin scale. Probably too coarse for use at the site scale. Scale: 1:500:000. Extent: Idaho. Projection: Albers. Source: ...

189

Digital solar system geology  

NASA Technical Reports Server (NTRS)

All available synoptic maps of the solid-surface bodies of the Solar System were digitized for presentation in the planned Atlas of the Solar System by Greeley and Batson. Since the last report (Batson et al., 1990), preliminary Uranian satellite maps were replaced with improved versions, Galilean satellite geology was simplified and digitized, structure was added to many maps, and the maps were converted to a standard format, with corresponding standing colors for the mapped units. Following these changes, the maps were re-reviewed by their authors and are now undergoing final editing before preparation for publication. In some cases (for Mercury, Venus, and Mars), more detailed maps were digitized and then simplified for the Atlas. Other detailed maps are planned to be digitized in the coming year for the Moon and the Galilean satellites. For most of the remaining bodies such as the Uranian satellites, the current digitized versions contain virtually all the detail that can be mapped given the available data; those versions will be unchanged for the Atlas. These digital geologic maps are archived at the digital scale of 1/16 degree/ pixel, in sinusoidal format. The availability of geology of the Solar System in a digital database will facilitate comparisons and integration with other data: digitized lunar geologic maps have already been used in a comparison with Galileo SSI observations of the Moon.

Batson, R. M.; Kozak, R. C.; Isbell, Nancy K.

1991-01-01

190

Appendix E: Geology  

SciTech Connect

This appendix provides a detailed description of geology under the Central Plateau of the Hanford Site, emphasizing the areas around tank farms. It is to be published by client CH2M HILL Hanford Group, Inc., as part of a larger, multi-contractor technical report.

Reidel, Steve; Chamness, Mickie A.

2008-01-17

191

Geology of Jewel Cave  

NSDL National Science Digital Library

This National Park Service site provides an introduction to the Black Hill's Jewel Cave. The site describes the unique geologic history of the Black Hills, the formation of speleothems as well as unusual crystal growth in the cave. Photographs illustrate the descriptions.

National Park Services (NPS)

192

Geology of California. Second Edition  

SciTech Connect

Two introductory chapters familiarize readers with basic geologic concepts. The following chapters describe the geology of each of California's 11 geomorphic provinces; the San Andreas fault and offshore geology are discussed in two separate chapters. Four appendices acquaint readers with technical words and terms, common minerals and rocks in California, geologic time, and geologic theories that pertain to California. During the 1960s evidence collected from the east Pacific sea floor off the western coast of North America gave scientists supporting data for Alfred Wegener's 1910 theory of continental drift. In addition to the confirmation of continental drift, since the 1960s scientists have discovered paleomagnetism, sea-floor spreading, exotic and suspect terranes, and polar wandering. These important concepts have had far reaching effects about how we understand the geology of California and how this region has evolved through geologic time. Improved investigative procedures enable earth scientists to comprehend previously puzzling aspects of California's geology.

Norris, R.M.; Webb, R.W.

1990-01-01

193

Using Snow to Teach Geology.  

ERIC Educational Resources Information Center

A lesson plan, directed at middle school students and older, describes using snow to study the geological processes of solidification of molten material, sedimentation, and metamorphosis. Provides background information on these geological processes. (MCO)

Roth, Charles

1991-01-01

194

Geologic Map Database of Texas  

USGS Publications Warehouse

The purpose of this report is to release a digital geologic map database for the State of Texas. This database was compiled for the U.S. Geological Survey (USGS) Minerals Program, National Surveys and Analysis Project, whose goal is a nationwide assemblage of geologic, geochemical, geophysical, and other data. This release makes the geologic data from the Geologic Map of Texas available in digital format. Original clear film positives provided by the Texas Bureau of Economic Geology were photographically enlarged onto Mylar film. These films were scanned, georeferenced, digitized, and attributed by Geologic Data Systems (GDS), Inc., Denver, Colorado. Project oversight and quality control was the responsibility of the U.S. Geological Survey. ESRI ArcInfo coverages, AMLs, and shapefiles are provided.

Stoeser, Douglas B.; Shock, Nancy; Green, Gregory N.; Dumonceaux, Gayle M.; Heran, William D.

2005-01-01

195

The Geological Society Web Shop  

NSDL National Science Digital Library

The Geological Society has launched an on-line bookshop, through which both Fellows and non-Fellows of the Society can purchase Geological Society books. Visitors can select books listed under the following headings: Tectonics, Economic Geology, Environmental, Petrology, Stratigraphy, Marine Studies, and Geophysics. The Geological Society Web Shop can be browsed or searched by keyword. Information on opening an account and purchasing books is available at the site.

196

Ordering Geologic Events and Interpreting Geologic History: The Grand Canyon  

NSDL National Science Digital Library

This activity is designed to help students recognize the connections among things like rock identification and map reading with the "story" that these things can tell us in terms of geologic history. Students have already learned about using observation to identify rocks and the principles of interpreting geologic cross-sections. The activity gives students practice in rock ID, topo map reading, geologic map reading and the aspects of geologic time. Students work with rock samples and a geologic map of the Grand Canyon to interpret a history for the area.

Jennifer Wenner

197

The Second Flowering of Geology.  

ERIC Educational Resources Information Center

Discusses two "golden" ages in geological investigations/inquiry. The first, extending from the late eighteenth century through the early nineteenth century, established geology as a science based on naturalistic principles. The second, beginning after World War II, is characterized by advances in geological specialities and explanations based on…

Cloud, Preston

1983-01-01

198

Environmental Trends in Geologic Education  

ERIC Educational Resources Information Center

Considers strategies for developing college level introductory environmental geology courses, emphasizing relevance to local surroundings, Considers graduate studies in this field, but does not recommend the establishment of an environmental geology department at this time. Reviews the responsibilities the geology department has to the community…

Pestrong, Raymond

1970-01-01

199

Geologic Map of New Jersey  

NSDL National Science Digital Library

This map displays the sedimentary rocks of the Cenozoic, Mesozoic, and Paleozoic eras as well as the igneous and metamorphic rocks of the Mesozoic and Precambrian eras. There is a pagesize copy of the geologic map, a brief description of the geology and physiographic provinces of New Jersey, and information on bedrock geologic maps of New Jersey (in CD-ROM format).

200

Geologic Map of North America  

USGS Multimedia Gallery

The Geologic Map of North America is a product of GSA's Decade of North American Geology (DNAG) project. At a scale of 1:5,000,000, this map covers ~15% of Earth's surface and differs from previous maps in several important respects: it is the first such map to depict the geology of the seafloor, th...

201

The Lapworth Museum of Geology  

E-print Network

The Lapworth Museum of Geology www.lapworth.bham.ac.uk www.bham.ac.uk Events The Lapworth Lectures take place on evenings during University term time. These lectures are on a wide range of geological geological topics, usually based around collections in the museum. These provide an opportunity to see

Birmingham, University of

202

September 2012 BASIN RESEARCH AND ENERGY GEOLOGY  

E-print Network

September 2012 BASIN RESEARCH AND ENERGY GEOLOGY STATE UNIVERSITY OF NEW YORK at BINGHAMTON research programs in geochemistry, sedimentary geology, or Earth surface processes with the potential the position, visit the Geological Sciences and Environmental Studies website (www.geology

Suzuki, Masatsugu

203

Geologic Maps and Geologic Structures: A Texas Example  

NSDL National Science Digital Library

This Historical Geology lab exercise is an accompaniment to lab class instruction about geologic structures (folding and faulting) and geologic maps. It also serves as an excellent introduction to the Geology of the state of Texas. "Coloring" geologic maps, an important part of the exercise, may seem like a very elementary learning technique. But this lab engages students actively, and since the subject is often already somewhat familiar to them, emphasizing both the geology and geography of Texas, students receive it enthusiastically. This activity could be adapted to other regions, since most states have color 8 1/2 by 11 geologic maps available. A color map could be scanned and modified in Photoshop to create a simplified black and white version as was done in the assignment handout.

Roger Steinberg

204

Geology of the Caribbean  

USGS Publications Warehouse

The Venezuelan and Colombian basins are located on the Caribbean Plate whilst the Yucatan basin is on the North American Plate. The processes occurring at the boundaries between the Caribbean Plate and the adjacent North American, South American and Cocos Plates, and the resulting surface features and patterns of volcanic and earthquake activity are described. Most of the Caribbean area is floored by atypical oceanic crust and its most valuable main geologic resources identified so far are petroleum, together with sand and gravel. Geological research is being carried out with techniques for broad-range swath imaging of the seafloor, such as GLORIA, and for directly measuring the movement between plates. -J.G.Harvey

Dillon, William P.; Edgar, N.T.; Scanlon, K.M.; Klitgord, Kim D.

1987-01-01

205

Geology Training Module  

NSDL National Science Digital Library

This is a lesson where learners review the basic requirements for human survival. Learners will use an online, multimedia module, to which they make changes to Earth's layers and draw conclusions about the geologic conditions that are necessary for human survival. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson one in the Astro-Venture Geology Training Unit that were developed to increase students' awareness of and interest in astrobiology and the many career opportunities that utilize science, math and technology skills. The lessons are designed for educators to use with the Astro-Venture multimedia modules.

206

Introduction to ore geology  

SciTech Connect

This textbook on ore geology is for second and third year undergraduates and closely parallels the undergraduate course given in this subject at England's University of Leicester. The volume covers three major areas: (1) principles of ore geology, (2) examples of the most important types of ore deposits, and (3) mineralization in space and time. Many chapters have been thoroughly revised for this edition and a chapter on diamonds has been added. Chapters on greisen and pegmatite have also been added, the former in response to the changing situation in tin mining following the recent tin crisis, and the latter in response to suggestions from geologists in a number of overseas countries. Some chapters have been considerably expanded and new sections added, including disseminated gold deposits and unconformity-associated uranium deposits. The author also expands on the importance of viewing mineral deposits from an economic standpoint.

Evans, A.M.

1987-01-01

207

Geological Survey research, 1975  

USGS Publications Warehouse

'Geological Survey Research 1975 ' is the 16th annual synopsis of the results of U.S. Geological Survey investigations. These studies are largely directed toward the development of knowledge that will assist the Nation to use and conserve the land and its physical resources wisely. They are wide ranging in scope and deal with almost every facet of solid-earth science and fact finding. Many of the studies are continuations of investigations that have been in progress for several years. But others reflect the increased attention being given to problems that have assumed greater importance in recent years--problems relating to mineral fuels and mineral resources, water quality, environmental impact of mineral resources, land-use analysis, earthquake hazards reduction, subsidence, and the applications of LANDSAT data, to cite a few examples. (Woodard-USGS)

U.S. Geological Survey

1975-01-01

208

Maryland Geological Survey  

NSDL National Science Digital Library

The Maryland Geological Survey (MGS) provides excellent information about the geology of the Old Line State, along with public reports and updates on various ongoing projects. The homepage features live earthquake data and maps that deal with oyster habitat restoration projects, fact sheets, and new reports on lead concentrations in well water across the state. The Publications area contains dozens of maps (such as that of the "Maryland Gold District") and links to Popular Publications such as "Caves of Maryland" and "Baltimore Building Stones Tour." The Data section is also quite useful, offering a number of informative data sets on sediment distribution in the Chesapeake Bay and Baltimore Harbor. Finally, the Education area contains an "Ask a Geologist" link that's quite useful for getting answers to Earth-based queries.

209

Algebra, Geology and Economics  

NSDL National Science Digital Library

The American Mathematical Association of Two-Year Colleges (AMATYC) has compiled a collection of mathematics resources related to various subjects and disciplines. â??Math Across the Community College Curriculumâ? is the title of the collection, which includes great math resources and applications for educators and students alike. In this particular resource, concepts from algebra, geology and economics are intertwined to create two dynamic activities for students. The projects, created by Mary Dowse, Tom Gruszka, and George Muncrief of Western New Mexico University, include both general learning objectives and subject specific objectives for what students will learn through the completion of the activities. The first activity focuses on the mathematics of economics, and the second activity focuses on geology and graphing. These activities can be easily adapted for use in the classroom, and are also useful for students who are looking for extra practice with these concepts.

Dowse, Mary

210

Oceanography - Marine Geological Processes  

NSDL National Science Digital Library

A first year course in oceanography with extensive Internet resources. Topics covered include: principles of thermodynamics, heat and mass transfer, fluid mechanics, continuum mechanics, and time-series analysis applied to marine geological and geophysical data; applications to transport of marine sediments; Pleistocene sedimentation and global climate change; and the thermal balance of the oceanic lithosphere. The link to the lecture schedule provides detailed supporting materials.

Mcduff, Russell

211

Integrating geology and perforating  

SciTech Connect

Perforating is a very common well completion operation. Usually, it is considered to be as simple as making holes in casing. Actually, perforating is one of the most critical tasks for establishing a path from reservoir rock to borehole form which hydrocarbons can flow to surface. The objective of this article is to relate perforating technology with geological aspects and completion type to determine the best shooting equipment (gun type, charge and differential pressure) to perform the most efficient perforating job. Several subjects related to formation geology are taken into account for a shooting job, such as: compressive strength, reservoir pressure and thickness, lithology type, porosity and permeability, ratio between horizontal and vertical permeabilities, and fluid type. Gun geometry used in the oil industry incorporates several parameters, including shot density, hole entrance diameter, gun phase and jet penetration. API tests are done on perforating guns to define applicability and performance. A new geometrical parameter is defined as the relative angle of the jet, which is the angle between the jet tunnel and formation dip. GEOCAN is a methodology which relates geology to gun geometry and type to define the most efficient gun system for perforated completions. It uses the intelligent perforating technique with the SPAN (Schlumberger Perforating Analysis) program to confirm optimum gun choice.

Araujo, P.F. de [Petrobras, Rio de Janeiro (Brazil); Souza Padilha, S.T.C. de [Schlumberger Wireline and Testing, Rio de Janeiro (Brazil)

1997-02-01

212

Terrestrial analogs, planetary geology, and the nature of geological reasoning  

NASA Astrophysics Data System (ADS)

Analogical reasoning is critical to planetary geology, but its role can be misconstrued by those unfamiliar with the practice of that science. The methodological importance of analogy to geology lies in the formulation of genetic hypotheses, an absolutely essential component of geological reasoning that was either ignored or denigrated by most 20th century philosophers of science, who took the theoretical/ experimental methodology of physics to be the sole model for all of scientific inquiry. Following the seminal 19th century work of Grove Karl Gilbert, an early pioneer of planetary geology, it has long been recognized that broad experience with and understanding of terrestrial geological phenomena provide geologists with their most effective resource for the invention of potentially fruitful, working hypotheses. The actions of (1) forming such hypotheses, (2) following their consequences, and (3) testing those consequences comprise integral parts of effective geological practice in regard to the understanding of planetary surfaces. Nevertheless, the logical terminology and philosophical bases for such practice will be unfamiliar to most planetary scientists, both geologists and nongeologists. The invention of geological hypotheses involves both inductive inferences of the type Gilbert termed “empiric classification” and abductive inferences of a logical form made famous by the 19th century American logician Charles Sanders Peirce. The testing and corroboration of geological hypotheses relies less on the correspondence logic of theoretical/ experimental sciences, like physics, and more on the logic of consistency, coherence, and consilience that characterizes the investigative and historical sciences of interpretation exemplified by geology.

Baker, Victor R.

2014-05-01

213

Geologic Setting of the Hamme Tungsten District, North Carolina and Virginia  

USGS Publications Warehouse

The Hamme tungsten district is in the eastern part of the Piedmont province, mainly in Vance County, North Carolina, but it extends a few miles into Virginia. The district is underlain by a central lenticular pluton of albite granodiorite that trends north-northeastward and is flanked on both sides by metamorphic rocks of low and medium grade that dip steeply westward. The relative ages of the metamorphic rocks are uncertain. The oldest rocks are likely to be the biotite gneisses in the eastern part of the district; successively younger units expose westward across the district are sericite-chlorite phyllites, greenstone, metafelsites, and metabasalts. The biotite gneisses and minor intercalated hornblende gneiss, which have a total thickness of many thousand feet, were derived from sediments. Some of the gneiss grades into phyllites and as probably formed by metasomatic alteration of the phyllites. Sericite-chlorite phyllite, epidote-quartz meta siltstone, quartzite, and conglomeratic phyllite occur principally in a wide belt on the west side of the central albite granodiorite. This unit is some 10,000 feet thick and originally consisted mainly of sediments of the graywacke suite. Greenstone totaling about 500 feet in thickness lies west of the phyllite and was derived from maflc lava flows and andesitic tuff. Metamorphosed massive aphanitic and porphyritic flows and dikes that range in composition from dacite to rhyolite, and phyllitic metatuffs and tuffaceous breccia are exposed west of the greenstone. These total at least 3,000 feet in thickness. Massive metabasalt that resembles greenstone but is less altered is common in the area between the Hamme district and the Virgilina district to the west. The thickness of the metabasalt is about 600 to 6,000 feet. The metamorphic rocks of the Hamme and Virgilina districts are parts of the Carolina slate belt, but map units cannot be directly correlated. Rocks in the Hamme district are thought by the writer to have been derived mainly from graywackes and volcanic flows, and subordinately from pyroclastic materials, whereas the rocks of the Virgilina district were interpreted by earlier workers as being mainly volcanic with much pyroclastic material but little sediment. Igneous, and perhaps pseudo igneous, rocks in the district include hornblende gabbro, albite granodiorite, aplite, and pegmatite--all of which are probably middle Paleozoic in age--and diabase and hypersthene tonalite of Late Triassic age. The gabbro forms three lenticular to subcircular bodies up to 2% miles in width in the western part of the area. Albite granodiorite forms a pluton with a maximum width of 7 miles which occupies the center of the area. At its northeastern end the pluton narrows abruptly to a point. Phyllite forms the wall rocks on all sides of the albite granodiorite. The contact is gradational and conformable in most places, but on the northwest side it cuts across wall structure for about 3 miles. Near its western edge the albite granodiorite includes a northeast-trending zone of schistose wall rock in and near which are localized the tungsten deposits. The origin of the albite granodiorite is uncertain, but it may have formed by the metasomatic replacement of the wallrocks, during which albite porphyroblasts developed first and were followed by microcline and quartz. Diabase and hypersthene tonalite occur as dikes and sills along four northward-trending belts. The dikes are a few feet to more than 300 feet thick, and several extend along strike for more than 10 miles. The Hamme district Is in the eastern part of the Carolina slate belt, and the Virg1l1na district lies along the western side of the belt. Rocks in the Hamme district dip mostly westward and in the Vifg1lina district dip mainly eastward into a syncline. This syncline, here named the Spewmarrow syncline, may be a structure of regional significance. Tungsten in the Hamme district occurs mainly

Parker, John Mason

1963-01-01

214

Aerogeophysical measurements of collapse-prone hydrothermally altered zones at Mount Rainier volcano  

USGS Publications Warehouse

Hydrothermally altered rocks can weaken volcanoes, increasing the potential for catastrophic sector collapses that can lead to destructive debris flows1. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes1-4 and the distribution and severity of subsurface alteration is largely unknown on any active volcano. At Mount Rainier volcano (Washington, USA), collapses of hydrothermally altered edifice flanks have generated numerous extensive debris flows5,6 and future collapses could threaten areas that are now densely populated7. Preliminary geological mapping and remote-sensing data indicated that exposed alteration is contained in a dyke-controlled belt trending east-west that passes through the volcano's summit3-5,8. But here we present helicopter-borne electromagnetic and magnetic data, combined with detailed geological mapping, to show that appreciable thicknesses of mostly buried hydrothermally altered rock lie mainly in the upper west flank of Mount Rainier. We identify this as the likely source for future large debris flows. But as negligible amounts of highly altered rock lie in the volcano's core, this might impede collapse retrogression and so limit the volumes and inundation areas of future debris flows. Our results demonstrate that high-resolution geophysical and geological observations can yield unprecedented views of the three-dimensional distribution of altered rock.

Finn, C.A.; Sisson, T.W.; Deszcz-Pan, M.

2001-01-01

215

Geology in North Dakota  

NSDL National Science Digital Library

The Department of Geosciences at North Dakota State University educates visitors about the geologic features and landforms of North Dakota through clear text and astonishing images at this website. In the Glacial Features of North Dakota link, visitors can learn about end moraines, eskers, kettle lakes, and kames. Educators can find amazing photographs of mass wasting including creep, slope failure, and slumps. Users can also find materials on stream features and satellite imagery of North Dakota. While the website concentrates on North Dakota, the materials can be a great addition to any earth science or geomorphology class.

216

The Geologic Time Scale  

NSDL National Science Digital Library

This site contains a large, easy to read, detailed geologic time scale for the Phanerozoic Eon (544 million years ago - Present). This is the period of time, also known as an eon, between the end of the Precambrian and today. The Phanerozoic begins with the start of the Cambrian period, 544 million years ago. It encompasses the period of abundant, complex life on Earth. The chart includes the Era, Period or System, and the Epoch or Series and features a brief description of each.

217

British Geological Survey: Geomagnetism  

NSDL National Science Digital Library

The British Geological Survey illustrates its work monitoring the earth's magnetic field in the UK at this website. Users can learn about the six observatories located in the Atlantic and the UK. Using the Grid Magnetic Angle Calculator, visitors can determine the angle between the British National grid north and the magnetic north. The website features Mercator projects created with the World Magnetic Model, geomagnetic data for the academic community, space weather services for industry, and more. Students can find tutorials about the Earth's magnetic field, magnetic reversals, and magnetic storms.

218

geology.com  

NSDL National Science Digital Library

This clearinghouse features an extensive selection of maps, imagery, news articles, and other Earth science resources. Highlights include an interactive map of meteor impact structures, an interactive map showing the highest points in the 50 states, and a state-by-state directory of imagery, maps, and links to geological information. There are also listings for imagery for U.S. cities and the continents, a map of the most dangerous volcanoes in the U.S., a mineral identification chart, and information on stream discharge monitoring.

2006-01-01

219

Geology Online Laboratory Manual  

NSDL National Science Digital Library

The 16 labs in this manual cover specific subjects from a range of topics including mineralogy, sedimentology, litho- and biostratigraphy, vertebrate and invertebrate paleontology, relative dating, and geologic map interpretation. Labs contain reference text, photos, illustrations, diagrams, and classification charts which prepare students for the accompanying exercises. Answers are not provided and labs are not designed for online interaction, but hard copies of the lab manual are available for purchase from the Georgia Perimeter College Online Bookstore. A link from the site provides ordering information and instructions.

Gore, P.; College, Georgia P.

220

Geologic mapping of Vesta  

NASA Astrophysics Data System (ADS)

We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High-Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were emplaced; these lie stratigraphically above the equatorial ridges that likely were formed by Rheasilvia. The last features to be formed were craters with bright rays and other surface mantling deposits. Executed progressively throughout data acquisition, the iterative mapping process provided the team with geologic proto-units in a timely manner. However, interpretation of the resulting map was hampered by the necessity to provide the team with a standard nomenclature and symbology early in the process. With regard to mapping and interpreting units, the mapping process was hindered by the lack of calibrated mineralogic information. Topography and shadow played an important role in discriminating features and terrains, especially in the early stages of data acquisition.

Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

2014-11-01

221

Structural Geology and Geomechanics  

NSDL National Science Digital Library

The teaching and research program, Structural Geology and Geomechanics at Stanford University, concentrates on brittle deformation in the earth's crust as well as fracturing and faulting of rocks under ductile conditions. Researchers can learn about the group's research which effectively unites field observations, laboratory experiments, and theoretical modeling. Scientists can learn about the program's software such as the Poly3Dinv which uses triangular dislocations to solve linear inverse problems. The site also publicizes the Stanford Rock Fracture Project, which researches rock fractures, crustal deformation, and fluid flow.

222

Geological Survey of Tanzania  

NSDL National Science Digital Library

The United Republic of Tanzania was formed in 1964 by the merger of Tanganyika and Zanzibar and is located on the eastern coast of Africa between the Great Lakes of the Rift Valley. Tanzania has a diverse mineral resource base that includes gold and base metals, diamond-bearing kimberlites, nickel, cobalt, copper, coal resources, and a variety of industrial minerals and rocks such as kaolin, graphite, and dimension stone. This web site was created by the Mineral Resources Department (MRD), a subsidiary of the Ministry of Energy and Minerals, and contains basic information about the country's logistical environment, mineral sector policy, geological database, and more.

1997-01-01

223

Petroleum geology of Tunisia  

SciTech Connect

Recent discoveries and important oil shows have proven the existence of hydrocarbons in newly identified depocenters and reservoirs. In general, except for some areas around the producing fields, Tunisia is largely underdrilled. The national company ETAP has decided to release data and to publish a synthesis on the petroleum geology of Tunisia. The geology of Tunisia provides a fine example of the contrast between Alpine folding, which typifies northern Tunisia and the African craton area of the Saharan part. Eastern Tunisia corresponds to an unstable platform forming plains or low hills and extending eastwards to the shallow Pelagian Sea. There are a wide variety of basins: central and northern Tunisia represents a front basin the Saharan Ghadames basin or the Chott trough are sag basins; the Gulf of Gabes was formed as a distension margin the Gulf of Hammamet is a composite basin and several transversal grabens cut across the country, including offshore, and are rift-type basins. All these features are known to be oil prolific throughout the world. Two large fields and many modest-size pools are known in Tunisia. Oil and gas fields in the surrounding countries, namely the Saharan fields of Algeria and Libya the large Bouri field offshore Tripolitania and discoveries in the Italian part of the Straits of Sicily, suggest a corresponding potential in Tunisia. Exposed paleogeographic and structural maps, balanced sections, and examples of fields and traps will support an optimistic evaluation of the future oil exploration in Tunisia.

Burollet, P.F. (CIFEG, Paris (France)); Ferjami, A.B.; Mejri, F. (ETAP, Tunis (Tunisia))

1990-05-01

224

Geol 102 Historical Geology The Geologic Timescale 2012  

E-print Network

.0 Triassic 252.2 - 201.3 Permian 298.9 - 252.2 Pennsylvanian Sub-period 323.2 - 298.9 Mississippian Sub-periodGeol 102 Historical Geology The Geologic Timescale 2012 EON ERA PERIOD (Special Units) EPOCH Range

Holtz Jr., Thomas R.

225

THREE-DIMENSIONAL GEOLOGIC MAPS AND VISUALIZATION  

E-print Network

#12;#12;THREE-DIMENSIONAL GEOLOGIC MAPS AND VISUALIZATION #12;THREE-DIMENSIONAL GEOLOGIC MAPS AND VISUALIZATION TRADITIONAL GEOLOGIC MAPS GOALS * To produce multipurpose geologic maps and databases of the San as `proof of concept' * To explore methods for analyzing, visualizing, and releasing 3D geologic maps

Militzer, Burkhard

226

WSU B.S. Geology Curriculum (structural)  

E-print Network

WSU B.S. Geology Curriculum Geology GEL 3300 (structural) GEL 3400 (sed/strat) Geology Elective 1 Geology Elective 2 Yr 1 Yr 2 Yr 3 Yr 4 PHY 2130/31 MAT 2010 PHY 2140/41 CHEM 1220/30 MAT 1800 Cognates GEL 5593 (writing intensive) GEL 3160 (petrology) GEL 3650 (field camp) Geology Elective 3 GEL 2130

Berdichevsky, Victor

227

Geologic Framework Model (GFM2000)  

SciTech Connect

The purpose of this report is to document the geologic framework model, version GFM2000 with regard to input data, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, and the differences between GFM2000 and previous versions. The version number of this model reflects the year during which the model was constructed. This model supersedes the previous model version, documented in Geologic Framework Model (GFM 3.1) (CRWMS M&O 2000 [DIRS 138860]). The geologic framework model represents a three-dimensional interpretation of the geology surrounding the location of the monitored geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain. The geologic framework model encompasses and is limited to an area of 65 square miles (168 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the geologic framework model (shown in Figure 1-1) were chosen to encompass the exploratory boreholes and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The upper surface of the model is made up of the surface topography and the depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The geologic framework model was constructed from geologic map and borehole data. Additional information from measured stratigraphic sections, gravity profiles, and seismic profiles was also considered. The intended use of the geologic framework model is to provide a geologic framework over the area of interest consistent with the level of detailed needed for hydrologic flow and radionuclide transport modeling through the UZ and for repository design. The model is limited by the availability of data and relative amount of geologic complexity found in an area. The geologic framework model is inherently limited by scale and content. The grid spacing used in the geologic framework model (200 feet [61 meters]), discussed in Section 6.4.2, limits the size of features that can be resolved by the model but is appropriate for the distribution of data available and its intended use. Uncertainty and limitations are discussed in Section 6.6 and model validation is discussed in Section 7.

T. Vogt

2004-08-26

228

76 FR 19783 - National Cooperative Geologic Mapping Program (NCGMP) and National Geological and Geophysical...  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF THE INTERIOR U.S. Geological Survey National Cooperative Geologic...Program (NCGMP) and National Geological and Geophysical Data Preservation...Advisory Committee AGENCY: U.S. Geological Survey, Interior. ACTION:...

2011-04-08

229

Mineral-chemical studies of metamorphosed hydrothermal alteration in the Kristineberg volcanogenic massive sulfide district, Sweden  

NASA Astrophysics Data System (ADS)

The massive sulfide deposits of the Kristineberg area, Sweden, occur within a 2- to 3-km-thick succession of felsic volcaniclastic rocks belonging to the Skellefte Group. The volcanic pile is intruded by a synvolcanic Jorn-type granitoid (Viterliden intrusive complex) and is overlain by a thick sequence of metasedimentary rocks (Vargfors Group). Mineralization occurs at two main stratigraphic levels, at the base of the felsic volcanic succession and at the contact with the metasedimentary rocks of the Vargfors Group. The Kristineberg Cu-Zn mine is the largest deposit (approximately 21 Mt) and occurs at the base of the volcanic pile, close to the contact with the Viterliden intrusive complex. Four smaller deposits (Ravliden, Ravlidmyran, Horntrask and Nyliden) occur along the upper ore horizon. These deposits are thought to be related to a late intrusive phase of the Viterliden complex which cuts the altered volcanic rocks at the Kristineberg deposit. Within an area of about 50 km2 surrounding the Kristineberg deposit, felsic volcanic rocks between the two ore horizons are affected by extensive albite-destructive alteration (sodium depletion) and development of chlorite and muscovite (strong co-enrichment in magnesium and potassium). The Kristineberg deposit is enveloped by a large and partly transposed quartz-chlorite alteration zone, approximately 2 km in diameter, and a distal but coherent pyrite-quartz-muscovite alteration zone extending as far as 4 km from the deposit. Chlorite(±talc) in the mine area is notably magnesium-rich and contains anomalous F, Ba, Zn and Mn. High fluorine is also present in coexisting muscovite and phlogopite. The magnesium-rich chlorite alteration contrasts sharply with the iron enrichment observed in many other felsic, volcanic-hosted Precambrian massive sulfide deposits. This may indicate fixation of iron by large amounts of pyrite in the section or entrainment of large amounts of seawater in the hydrothermal upflow zones. Kyanite is developed locally in the chlorite-rich pipe at Kristineberg in response to regional thermal metamorphism of highly aluminous alteration in the immediate foot-wall rocks. Spectacular, andalusite-bearing quartz-muscovite schists and quartz-biotite-cordierite schists also occur where the altered felsic volcanic rocks are intruded by the late Revsund granite. However, similar metamorphic mineral growth is not observed where the volcanic rocks at the contact are less altered. Deposits near the top of the felsic volcanic succession are characterized by magnesium-rich chlorite alteration in the foot wall and proximal calc-silicate assemblages (dolomite, calcite, tremolite, ±garnet, ±margarite) where the host sedimentary rocks are carbonate-rich. In general, the calc-silicate alteration is restricted to the immediate hanging wall and zones lateral to the deposits and does not represent a regionally extensive exploration target. The two main ore horizons in the Kristineberg area are not linked by any obvious discordant structures or alteration zones. However, mineral-chemical studies highlight several possible fluid flow pathways leading from the Kristineberg deposit to the Ravliden ore horizon, more than 2 km upsection. Overprinting regional metamorphic minerals have inherited the hydrothermal signature of the ore-related alteration. Electronic Supplementary Material is available at http://dx.doi.org/10.1007/s00126-002-0299-y. On that page (frame on the left side), a link takes you directly to the supplementary material.

Hannington, Mark D.; Kjarsgaard, Ingrid M.; Galley, Alan G.; Taylor, Bruce

2003-06-01

230

Osmotic generation of 'anomalous' fluid pressures in geological environments  

USGS Publications Warehouse

Osmotic pressures are generated by differences in chemical potential of a solution across a membrane. But whether osmosis can have a significant effect on the pressure of fluids in geological environments has been controversial, because the membrane properties of geological media are poorly understood. 'Anomalous' pressures - large departures from hydrostatic pressure that are not explicable in terms of topographic or fluid-density effects are widely found in geological settings, and are commonly considered to result from processes that alter the pore or fluid volume, which in turn implies crustal changes happening at a rate too slow to observe directly. Yet if osmosis can explain some anomalies, there is no need to invoke such dynamic geological processes in those cases. Here I report results of a nine- year in situ measurement of fluid pressures and solute concentrations in shale that are consistent with the generation of large (up to 20 MPa) osmotic-pressure anomalies which could persist for tens of millions of years. Osmotic pressures of this magnitude and duration can explain many of the pressure anomalies observed in geological settings. The require, however, small shale porosity and large contrasts in the amount of dissolved solids in the pore waters - criteria that may help to distinguish between osmotic and crystal-dynamic origins of anomalous pressures.

Neuzii, C.E.

2000-01-01

231

GEOLOGY, October 2011 955 INTRODUCTION  

E-print Network

., 2006). In particular, the underlying Arabian-Nubian Shield (ANS) was designated a likely provenanceGEOLOGY, October 2011 955 INTRODUCTION The early Paleozoic sequence at the northern periphery (in­ Cambrian landscape of northern Gondwana. Geology, October 2011; v. 39; no. 10; p. 955­958; doi:10.1130/G

Dov, Avigad

232

Computer Assisted Instruction in Geology.  

ERIC Educational Resources Information Center

The development of a computer self-test program in geology at Macalester College, Minnesota, is described. Based on the philosophy that tests, particularly those involving no grading, are useful study devices, computers are used to make tests available to students. Ten lessons have been developed on different topics in geology, and the computer…

Lepp, Henry

233

Geologic mapping of Argyre Planitia  

NASA Technical Reports Server (NTRS)

This report describes the results from the geologic mapping of the central and southern Argyre basin of Mars. At the Mars Geologic Mapper's Meeting in Flagstaff during July, 1993, Dave Scott (United States Geological Survey, Mars Geologic Mapping Steering Committee Chair) recommended that all four quadrangles be combined into a single 1:1,000,000 scale map for publication. It was agreed that this would be cost-effective and that the decrease in scale would not compromise the original science goals of the mapping. Tim Parker completed mapping on the 1:500,000 scale base maps, for which all the necessary materials had already been produced, and included the work as a chapter in his dissertation, which was completed in the fall of 1994. Geologic mapping of the two southernmost quadrangles (MTM -55036 and MTM -55043; MTM=Mars Transverse Mercator) was completed as planned during the first year of work. These maps and a detailed draft of the map text were given a preliminary review by Dave Scott during summer, 1993. Geologic mapping of the remaining two quadrangles (MTM -50036 and MTM -50043) was completed by summer, 1994. Results were described at the Mars Geologic Mappers Meeting, held in Pocatello, Idaho, during July, 1994. Funds for the third and final year of the project have been transferred to the Jet Propulsion Laboratory, where Tim Parker will revise and finalize all maps and map text for publication by the United States Geological Survey at the 1:1,000,000 map scale.

Gorsline, Donn S.; Parker, Timothy J.

1995-01-01

234

GEOLOGY, June 2009 483 INTRODUCTION  

E-print Network

GEOLOGY, June 2009 483 INTRODUCTION Fine-grained sedimentary rocks (grain size known as shales or mud- stones, are the most abundant sedimentary rock type. They contain the bulk of geologic his- tory recorded in sedimentary rocks (Schieber, 1998), and are a key element in organic

Polly, David

235

Geologic disposal of nuclear waste  

Microsoft Academic Search

The natural and engineered barriers provided by geologic storage of nuclear wastes are the most likely choice of countries looking for a permanent solution. A review of the properties of nuclear wastes and the management strategies that will protect the public and the environment describes the isolation and disposal systems and their geologic requirements. These include a host-rock formation of

K. Stahlkopf; R. Williams; A. B. Carson

1982-01-01

236

Photomicrography in the Geological Sciences.  

ERIC Educational Resources Information Center

Describes the conversion of a standard biological brightfield microscope for examination of thin sections and characterize, in detail, the use of both black and white and color photomicrography in the geological sciences. Several illustrative examples on the use of transmitted and reflected polarized-light microscopy to solve geological problems…

Davidson, Michael W.

1991-01-01

237

DEPARTMENT OF GEOLOGY & GEOPHYSICS UNDERGRADUATE  

E-print Network

DEPARTMENT OF GEOLOGY & GEOPHYSICS UNDERGRADUATE SURVIVAL MANUAL 2013-2014 SCHOOL OF OCEAN & EARTH and Geophysics 1 Job Opportunities 1 Prepare Educationally 1 Challenges and Rewards 1 THE DEPARTMENT OF GEOLOGY & GEOPHYSICS 2 Who We Are 2 Where To Get Help 2 POLICIES, PROCEDURES & REQUIREMENTS 3 University of Hawaii

238

The Geophysical Revolution in Geology.  

ERIC Educational Resources Information Center

Discussed is the physicists' impact on the revolution in the earth sciences particularly involving the overthrow of the fixist notions in geology. Topics discussed include the mobile earth, the route to plate tectonics, radiometric dating, the earth's magnetic field, ocean floor spreading plate boundaries, infiltration of physics into geology and…

Smith, Peter J.

1980-01-01

239

Geology orbiter comparison study  

NASA Technical Reports Server (NTRS)

Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives.

Cutts, J. A. J.; Blasius, K. R.; Davis, D. R.; Pang, K. D.; Shreve, D. C.

1977-01-01

240

Geological consequences of superplumes  

SciTech Connect

Superplumes are suggested to have caused the period of constant normal magnetic polarity in mid-Cretaceous time (124-83 Ma) and, possibly, the period of constant reversed polarity in Pennsylvania-Permian time (323-248 Ma). These times coincide with increases in world temperature, deposition of black shales, oil generation, and eustatic sea level in the mid-Cretaceous, and increased coal generation and gas accumulation in the Pennsylvanian-Permian, accompanied by an intracratonic Pennsylvanian transgression of epicontinental seas. These geologic anomalies are associated with episodes of increased world-wide ocean-crust production and mantle outgassing, especially of carbon and nutrients. These superplumes originated just above the core-mantle boundary, significantly increased convection in the outer core, and stopped the magnetic field reversal process for 41 m.y. in the Cretaceous and 75 m.y. in Pennsylvanian-Permian time.

Larson, R.L. (Univ. of Rhode Island, Narragansett (United States))

1991-10-01

241

Geology in the News  

NSDL National Science Digital Library

For this activity students read the newspaper on a daily basis, listen to news on the radio, or watch television, to acquire material related to the earth sciences. They will look for natural hazards (earthquakes, volcanoes, landslides, hurricanes, etc.), human-made hazards (urbanization, compromised engineering projects, etc.), environmental issues, or resource extraction issues which all appear in the news with great frequency and are easily accessible. Students are reminded that they should look for information on the local level (water quality, solid waste management, development issues, etc.), as well as national and world wide issues. The news items may then be presented to the class as show-and-tell exercises with follow-up discussion by the class; a bulletin board that could be dedicated to posting the geologic events of the week; or scrapbooks of events, arranged either chronologically or by category of events compiled by individuals or classes.

David Mogk

242

Surficial Geologic Map of Maine  

NSDL National Science Digital Library

In this activity students become familiar with the nature and use of the Surficial Geologic Map of Maine and gain practice in using maps other than topographic maps. They will discover that surficial geology deals primarily with the geologically youthful, unconsolidated sedimentary materials that exist at, or close to the surface of a specific area and are important because the surface deposits filter and control the access of water to the water table. Students also learn that the study of surficial geology is important for siting of waste disposal facilities and for resources such as sand, gravel, and clay. Although this activity was written for a map of Maine, it will work in any state where surficial geological maps are available.

243

Mineral resources, geological structure, and landform surveys  

NASA Technical Reports Server (NTRS)

Diagnostic ERTS imagery has been used to pinpoint surface conditions associated with known mining districts. These include enhancements which depict hitherto unrecognized surface alteration and allow analysis of ore-controlling fractures distribution in a regional context. ERTS has likewise provided observational data containing previously unrecognized surface anomalies in large oil-producing basins which correlate closely with known oil fields. These observational data offer promise of providing new and powerful techniques for oil exploration, especially if further work using more sophisticated enhancement-processing proves capable of emphasizing the anomalies. ERTS is showing a better-than-anticipated potential for producing accurate small-scale (large-area) geologic maps, often containing details that were previously not recorded on similar regional maps. The maps produced from ERTS imagery can be prepared more effectively than previously possible, mainly because of the synoptic, multispectral, and repetitive character of ERTS data. ERTS has also provided extensive information on possible geologic hazards. Many new fractures have been identified in several regions of the Pacific Coast seismic belt that have histories of recent earthquakes. This has obvious implications for engineering projects such as dams, aqueducts, and transportation routes. In the mid-continent area, ERTS data have been used to predict zones of rooffall danger in a working coal mine from newly discovered lineations (probably fractures) used as indicators of hazards.

Short, N. M.

1974-01-01

244

Mapping hydrothermal alteration in Yellowstone National Park using magnetic methods  

NASA Astrophysics Data System (ADS)

Yellowstone National Park (YNP) hosts a very large hydrothermal system with over 10,000 thermal features. Hydrothermal alteration in YNP has been mapped with field observations and remote-sensing imagery, but these methods can only detect alteration at the ground surface. Magnetic surveys are useful for detecting buried hydrothermal alteration as demonstrated by a recent high-resolution aeromagnetic survey in YNP (Finn and Morgan, J. Volcanol. Geotherm. Res., 115, 207-231, 2002). Results of this survey show that magnetic lows extend over and beyond areas of hydrothermal activity, suggesting large volumes of demagnetized rocks due to hydrothermal alteration of the volcanic substratum. Although results of this aeromagnetic survey were of relatively high resolution, they were insufficient for more detailed mapping of alteration. In September 2008, we collected ground magnetic profiles in four hydrothermal areas within YNP (Norris Geyser Basin, Lower Geyser Basin, Lone Star Geyser, and Smoke Jumper Hot-springs). These measurements were performed using a cesium-vapor magnetometer along several 4-5 km long transects crossing hydrothermal features. In addition, we collected gravity data to characterize the subsurface geologic structures. We also performed magnetic susceptibility, magnetic remanence and density measurements on rock samples collected in the field and from drill cores collected in 1967-1968 to characterize physical properties of fresh and altered geologic units. Ground magnetic profiles acquired over unaltered areas display large-amplitude short-wavelength anomalies due to the existence of many shallow contrasts of magnetization in the volcanic substratum. In contrast, the short-wavelength anomaly signal is of very low amplitude in altered areas supporting demagnetization of the shallow volcanic basement. These new geophysical and physical property data are being used to map the distribution of rock density and magnetic properties, model the subsurface geometry of altered areas and investigate the relationship of these areas with structures such as contacts, faults, and fractures that may facilitate the circulation of hydrothermal fluids.

Bouligand, C.; Glen, J. M.

2010-12-01

245

49 CFR 801.59 - Geological records.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Geological records. 801.59 Section...Public Disclosure § 801.59 Geological records. Pursuant to 5 U...b)(9), records concerning geological wells are exempt from public...

2010-10-01

246

Geological Survey Research 1966, Chapter B  

USGS Publications Warehouse

This collection of 43 short papers is the first published chapter of 'Geological Survey Research 1966.' The papers report on scientific and economic results of current work by members of the Conservation, Geologic, Topographic, and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done during fiscal year 1966, together with lists of investigations in progress, reports published, cooperating agencies, and Geological Survey offices. 'Geological Survey Research 1966' is the seventh volume of the annual series Geological Survey Research. The six volumes already published are listed below, with their series designations. Geological Survey Research 1960-Prof. Paper 400 Geological Survey Research 1961-Prof. Paper 424 Geological Survey Research 1962-Prof. Paper 450 Geological Survey Research 1963-Prof. Paper 475 Geological Survey Research 1964-Prof. Paper 501 Geological Survey Research 1965-Prof. Paper 525

U.S. Geological Survey

1966-01-01

247

Geology Fieldnotes: Grand Canyon National Park, Arizona  

NSDL National Science Digital Library

Visitors can access park geology information, photographs, related links, visitor information, multimedia resources, and resources for teaching geology with National Park examples. The park geology section discusses the Grand Canyon's geologic history, structural geology, and features a question-and-answer section about the canyon. The history of the canyon as a park and environmental issues surrounding it are also discussed. A geologic cross section of the canyon showing the various rock layers is included.

248

The Geologic Nitrogen Cycle  

NASA Astrophysics Data System (ADS)

N2 is the dominant gas in Earth's atmosphere, and has been so through the majority of the planet's history. Originally thought to only be cycled in significant amounts through the biosphere, it is becoming increasingly clear that a large degree of geologic cycling can occur as well. N is present in crustal rocks at 10s to 100s of ppm and in the mantle at 1s to perhaps 10s of ppm. In light of new data, we present an Earth-system perspective of the modern N cycle, an updated N budget for the silicate Earth, and venture to explain the evolution of the N cycle over time. In an fashion similar to C, N has a fast, biologically mediated cycle and a slower cycle driven by plate tectonics. Bacteria fix N2 from the atmosphere into bioavailable forms. N is then cycled through the food chain, either by direct consumption of N-fixing bacteria, as NH4+ (the primary waste form), or NO3- (the most common inorganic species in the modern ocean). Some organic material settles as sediment on the ocean floor. In anoxic sediments, NH4+ dominates; due to similar ionic radii, it can readily substitute for K+ in mineral lattices, both in sedimentary rocks and in oceanic lithosphere. Once it enters a subduction zone, N may either be volatilized and returned to the atmosphere at arc volcanoes as N2 or N2O, sequestered into intrusive igneous rocks (as NH4+?), or subducted deep into the mantle, likely as NH4+. Mounting evidence indicates that a significant amount of N may be sequestered into the solid Earth, where it may remain for long periods (100s m.y.) before being returned to the atmosphere/biosphere by volcanism or weathering. The magnitude fluxes into the solid Earth and size of geologic N reservoirs are poorly constrained. The size of the N reservoirs contained in the solid Earth directly affects the evolution of Earth's atmosphere. It is possible that N now sequestered in the solid Earth was once in the atmosphere, which would have resulted in a higher atmospheric pressure, and therefore strengthened the greenhouse effect by pressure broadening the absorption of greenhouse gases. In addition,the behaviour of N is dependent on redox conditions in the ocean, which have not been constant over time.

Johnson, B. W.; Goldblatt, C.

2013-12-01

249

National Archive of Geological Photographs  

NSDL National Science Digital Library

Provided by the British Geological Survey, this site contains a database of some 6,400 digitized images drawn from the National Archive of Geological Photographs (NAGP). The archive may be searched by keyword, advanced search, or browsed via themed galleries (Montserrat Volcanic Eruption, Beltmoss Quarry - working stone, Aerial photographs in and around Edinburgh, etc.). Unfortunately, the images are only available in one, rather small, size. They are accompanied by information on location, photographer, geologist, year taken, and descriptions of varying length. Additional information on the British Geological Survey may be accessed from the main page.

250

Geol 102 Historical Geology The Geologic Timescale 2011  

E-print Network

Geol 102 Historical Geology The Geologic Timescale 2011 EON ERA PERIOD (Special Units) EPOCH Range 65.5 - 55.8 Mesozoic Cretaceous 145.5 - 65.5 Jurassic 201.5 - 145.5 Triassic 252.3 - 201.5 Paleozoic Permian 299.0 - 252.3 Carboniferous Pennsylvanian Sub-period 318.1 - 299.0 Mississippian Sub-period 359

Holtz Jr., Thomas R.

251

Geol 102 Historical Geology The Geologic Timescale 2009  

E-print Network

Geol 102 Historical Geology The Geologic Timescale 2009 EON ERA PERIOD (Special Units) EPOCH Range.5 - 55.8 Mesozoic Cretaceous 145.5 - 65.5 Jurassic 199.6 - 145.5 Triassic 251.0 - 199.6 Paleozoic Permian 299.0 - 251.0 Carboniferous Pennsylvanian Sub-period 318.1 - 299.0 Mississippian Sub-period 359

Holtz Jr., Thomas R.

252

Coyote Creek Geologic Map  

NSDL National Science Digital Library

Students are required to make field observations, collect data and then create a detailed geologic map and report for a small area (approximately 1 sq. mile) on the edge of the Tularosa Basin in south central New Mexico. The study area is located within the Tularosa NE quadrangle, but maps from the Cat Mountain quadrangle to the East are also useful. Gently dipping carbonate and siliciclastic beds, igneous intrusions, bioherms and a normal fault are present in the study area along Coyote Creek, a few miles north of Tularosa, NM. The creek generally runs parallel to dip, allowing relatively easy access to inclined strata. Bioherm(s) are present in the lower section. Several dikes are present running both parallel and perpendicular to sedimentary bed strike. One is very non-resistant to weathering, creating unusual troughs as it passes through the carbonate bioherms. A sill is present in the upper section and a N/S trending normal fault roughly parallels strike of sedimentary beds.

Walsh, Timothy R.

253

Uranium geology of Bulgaria  

SciTech Connect

Three major uranium districts containing several deposits, plus 32 additional deposits, have been identified in Bulgaria, all of which are detailed geologically in this article. Most of the deposits are located in the West Balkan mountains, the western Rhodope mountains, and the Thracian Basin. A few deposits occur in the East Balkan, eastern Rhodope and Sredna Gora mountains. The types of deposits are sandstone, vein, volcanic, and surficial. Sandstone deposits are hosted in Permian and Tertiary sediments. In early 1992, fifteen deposits were being exploited, of which roughly 70 percent of the uranium produced was being recovered using in-situ leaching (ISL) methods. The remainder was being recovered by conventional underground mining, except for one small deposit that utilized open-pit methods. Fifteen other Bulgarian deposits had been exhausted, while five deposits were still in the exploration stage. Uranium production began in Bulgaria in 1946, and cumulative production through 1991 exceeded 100 million pounds equivalent U3O8. Current annual production is on the order of one million pounds equivalent U3O8, about 750 thousand pounds of which are recovered by ISL operations.

Not Available

1993-02-01

254

Oncogenic alterations of metabolism  

Microsoft Academic Search

Over seven decades ago, classical biochemical studies showed that tumors have altered metabolic profiles and display high rates of glucose uptake and glycolysis. Although these metabolic changes are not the fundamental defects that cause cancer, they might confer a common advantage on many different types of cancers, which allows the cells to survive and invade. Recent molecular studies have revealed

Chi V. Dang; Gregg L. Semenza

1999-01-01

255

Pattern Alteration: Shoulder Length  

E-print Network

Wide or broad shoulders will cause the armhole seam line at the shoulder to pull inward and the cap of set-in sleeves to pull and ride up. Sleeves will appear too short and not hang properly. This publication gives instructions for altering a basic...

2006-08-04

256

How Misinformation Alters Memories.  

ERIC Educational Resources Information Center

Notes that a multitude of studies have demonstrated that misleading postevent information affects people's memories. Contents that the fuzzy-trace theory is a positive step toward understanding the malleability of memory. Discusses fuzzy-trace theory in terms of three primary areas of study: altered response format, maximized misinformation…

Wright, Daniel B.; Loftus, Elizabeth F.

1998-01-01

257

GeologicBoulderMap Writtenandeditedby  

E-print Network

has a composition closer to a granodiorite than a granite. Similarly, the granite used for the stairs at the entrance to the Thorvaldson Building is also granodioritic in composition. Glossary of Geological Terms

Patterson, William P.

258

Terrestrial and Lunar Geological Terminology  

NASA Technical Reports Server (NTRS)

This section is largely a compilation of defining geological terms concepts. Broader topics, such as the ramifications for simulant design and in situ resource utilization, are included as necessary for context.

Schrader, Christian

2009-01-01

259

Outreach at Geology Camp 2008  

USGS Multimedia Gallery

USGS Hydrologist, Andy Long, demonstrates an interactive groundwater-flow model in the USGS South Dakota Water Science Center laboratory to students attending Geology Camp with the South Dakota School of Mines in 2008....

260

Geologic constraints on seismic inversion  

SciTech Connect

Velocity model estimation from seismic data using prestack depth migration is an underdetermined problem: there are many subtly different models which are not kinematically equivalent. As these models can give rise to dramatically different interpretations and decisions there is a clear need for a selection criterion in order to choose the best (i.e. geologically most plausible) one. Interpreter guided velocity estimation provides this criterion but is nonreproducible and nonquantifiable while automatic methods (which are reproducible and quantifiable) will find just one out of many kinematically equivalent models and mostly one which is geologically not attractive. Application of geologic constraints in conjunction with inversion by Differential Semblance Optimization produces models that are both geologically appealing, kinematically correct and have a very good fit to observed data.

Versteeg, R.J.; Symes, W.W. [Rice Univ., Houston, TX (United States)

1994-12-31

261

Physical Geology on the Fringe  

NSDL National Science Digital Library

Dr. Robert C. Thomas, The University of Montana Western Summary This 3-week field trip includes a 5-day field excursion that explores the geology and cultural history of the Khumbu region of Nepal, the famous ...

262

JiTT - Geologic Dating  

NSDL National Science Digital Library

1) How are zircons formed? 2) Which of the following statements describes relative geologic dating? a) the Triceratops and Tyrannosaurus rex went extinct at the same time b) dinosaurs came later than horseshoe ...

Guertin, Laura

263

Perspectives in geology. Circular 525  

SciTech Connect

The papers in this symposium present diverse perspectives in geology, mineral resources, paleontology, and environmental concerns. Papers within the scope of EDB have been entered individually into the data base. (ACR)

Not Available

1982-01-01

264

Carbon Capture and Geologic Storage  

NASA Astrophysics Data System (ADS)

This paper will briefly discuss carbon capture and storage options, mechanisms and costs. Risks from geologic storage risks will be addressed and the need for monitoring. Some current field studies will be described.

Myer, Larry R.

2008-09-01

265

Internet Community for Geological Engineers  

NSDL National Science Digital Library

A site containing multiple resources for geological engineers. Contains current news headlines in oil, energy, and mining; information on borehole breakouts, hydraulic fracturing, core discing, pressurized slot testing, nuclear high level waste disposal, and water infrastructure security.

266

Central American geologic map project  

SciTech Connect

During the Northeast Quadrant Panel meeting of the Circum-Pacific Map Project held in Mexico City, February 1985, Central American panel members proposed and adopted plans for compiling a geologic map of Central America, probably at a scale of 1:500,000. A local group with participants from each country was organized and coordinated by Rolando Castillo, director, Central American School of Geology, University of Costa Rica, for the geologic aspects, and Fernando Rudin, director, Geographic Institute of Costa Rica, for the topographic base. In 1956, the US Geological Survey published a geologic map of the region at a scale of 1:1 million. Subsequent topographic and geologic mapping projects have provided a large amount of new data. The entire area is now covered by topographic maps at a scale of 1:50,000, and these maps have been used in several countries as a base for geologic mapping. Another regional map, the Metallogenic Map of Central America (scale = 1:2 million), was published in 1969 by the Central American Research Institute for Industry (ICAITI) with a generalized but updated geologic base map. Between 1969 and 1980, maps for each country were published by local institutions: Guatemala-Belize at 1:500,000, Honduras at 1:500,000, El Salvador at 1:100,000, Nicaragua at 1:1 million, Costa Rica at 1:200,000, and Panama at 1:1 million. This information, in addition to that of newly mapped areas, served as the base for the Central American part of the Geologic-Tectonic Map of the Caribbean Region (scale = 1:2.5 million), published by the US Geological Survey in 1980, and also fro the Northeast Quadrant Maps of the Circum-Pacific Region. The new project also involves bathymetric and geologic mapping of the Pacific and Caribbean margins of the Central American Isthmus. A substantial amount of new information of the Middle America Trench has been acquired through DSDP Legs 67 and 84.

Dengo, G.

1986-07-01

267

An overview of Venus geology  

NASA Astrophysics Data System (ADS)

The Magellan spacecraft is producing comprehensive image and altimetry data for the planet Venus. Initial geologic mapping of the planet reveals a surface dominated by volcanic plains and characterized by extensive volcanism and tectonic deformation. Geologic and geomorphologic units include plains terrains, tectonic terrains, and surficial material units. Understanding the origin of these units and the relation between them is an ongoing task of the Magellan team.

Saunders, R. S.; Arvidson, R. E.; Head, J. W.; Schaber, G. G.; Stofan, E. R.; Solomon, S. C.

1991-04-01

268

Geological Surveys Bureau Browse Area  

NSDL National Science Digital Library

Offered by the Iowa Geological Survey Bureau, the Browse Area page is a great collection of articles, photos, and maps about the state's geology geared especially to the public. Topics include Age of Dinosaurs in Iowa, Landscape Features, Satellite Image, Field Travels of Early Iowa Geologists, Meteorites in Iowa's History, Oil Exploration, and much more. This is a wonderful example of how government can provide informative and fun sites to the public without going overboard with high-end and complicated Web design.

269

Bedrock geologic map of Vermont  

USGS Publications Warehouse

The Bedrock Geologic Map of Vermont is the result of a cooperative agreement between the U.S. Geological Survey (USGS) and the State of Vermont. The State's complex geology spans 1.4 billion years of Earth's history. The new map comes 50 years after the most recent map of the State by Charles G. Doll and others in 1961 and a full 150 years since the publication of the first geologic map of Vermont by Edward Hitchcock and others in 1861. At a scale of 1:100,000, the map shows an uncommon level of detail for State geologic maps. Mapped rock units are primarily based on lithology, or rock type, to facilitate derivative studies in multiple disciplines. The 1961 map was compiled from 1:62,500-scale or smaller maps. The current map was created to integrate more detailed (1:12,000- to 1:24,000-scale) modern and older (1:62,500-scale) mapping with the theory of plate tectonics to provide a framework for geologic, tectonic, economic, hydrogeologic, and environmental characterization of the bedrock of Vermont. The printed map consists of three oversize sheets (52 x 76 inches). Sheets 1 and 2 show the southern and northern halves of Vermont, respectively, and can be trimmed and joined so that the entire State can be displayed as a single entity. These sheets also include 10 cross sections and a geologic structure map. Sheet 3 on the front consists of descriptions of 486 map units, a correlation of map units, and references cited. Sheet 3 on the back features a list of the 195 sources of geologic map data keyed to an index map of 7.5-minute quadrangles in Vermont, as well as a table identifying ages of rocks dated by uranium-lead zircon geochronology.

Ratcliffe, Nicholas M.; Stanley, Rolfe S.; Gale, Marjorie H.; Thompson, Peter J.; Walsh, Gregory J.; With contributions by Hatch, Norman L., Jr.; Rankin, Douglas W.; Doolan, Barry L.; Kim, Jonathan; Mehrtens, Charlotte J.; Aleinikoff, John N.; McHone, J. Gregory; Cartography by Masonic, Linda M.

2011-01-01

270

Community Perceptions of Geologic Sequestration  

NASA Astrophysics Data System (ADS)

Political momentum for mitigating climate change through the use of large-scale energy technologies such as geologic sequestration is growing. This paper explores the views of communities living near an actual or potential geologic sequestration project site. Given the potential importance of geologic sequestration to U.S. energy policy, what might explain and influence the views of this technology by the community-members. Through focus groups and one-on-one interviews, we gathered the views of two communities in California's Central Valley. One community close to a Department of Energy sponsored geologic sequestration pilot-project and another similarly located community that is not actually a project site. Our analysis combined a review of the history of the communities with other technologies and their social and economic indicators with the results of the focus groups and interviews. The results suggest that the sense of community empowerment, as contextualized by the history of the community and socio-economic indicators, is an important indicator of positive views of geologic sequestration. In addition, the results indicate community members prefer to be informed about geologic sequestration from a variety of sources (e.g., academia and industry).

Wong-Parodi, G. M.; Farrell, A.; Ray, I.

2007-12-01

271

242 Department of Geology Undergraduate Catalogue 201415  

E-print Network

242 Department of Geology Undergraduate Catalogue 2014­15 Department of Geology Chairperson: Abdel. Assistant Instructor: P Hajj-Chehadeh, Abdel-Halim The Department of Geology offers programs leading to the degree of Bachelor of Science in Geology, and Master of Science degrees in certain areas of the vast

272

Reprinted February 2003 4-H Geology  

E-print Network

4-H 340 Reprinted February 2003 4-H Geology Member Guide OREGON STATE UNIVERSITY EXTENSION SERVICE #12;Contents 4-H Geology Project 3 Project Recommendations 3 Books on Geology 4 Trip Planning 4 Contests 7 Identification of Rocks and Minerals 7 Physical Properties of Minerals 8 Generalized Geologic

Tullos, Desiree

273

Geology of the Shenandoah National Park Region  

E-print Network

1 Geology of the Shenandoah National Park Region 39th Annual Virginia Geological Field Conference October 2nd - 3rd, 2009 Scott Southworth U. S. Geological Survey L. Scott Eaton James Madison University Meghan H. Lamoreaux College of William & Mary William C. Burton U. S. Geological Survey Christopher M

Eaton, L. Scott

274

Assessment Report, Department of Geology August, 2012  

E-print Network

Assessment Report, Department of Geology August, 2012 1. Learning Goals ALL students in geology, classification schemes, geologic history and processes, and the structure of the Earth. 3. demonstrate an understanding of the variability, complexity, and interdependency of processes within geologic systems. 4. use

Bogaerts, Steven

275

Health benefits of geologic materials and geologic processes  

USGS Publications Warehouse

The reemerging field of Medical Geology is concerned with the impacts of geologic materials and geologic processes on animal and human health. Most medical geology research has been focused on health problems caused by excess or deficiency of trace elements, exposure to ambient dust, and on other geologically related health problems or health problems for which geoscience tools, techniques, or databases could be applied. Little, if any, attention has been focused on the beneficial health effects of rocks, minerals, and geologic processes. These beneficial effects may have been recognized as long as two million years ago and include emotional, mental, and physical health benefits. Some of the earliest known medicines were derived from rocks and minerals. For thousands of years various clays have been used as an antidote for poisons. "Terra sigillata," still in use today, may have been the first patented medicine. Many trace elements, rocks, and minerals are used today in a wide variety of pharmaceuticals and health care products. There is also a segment of society that believes in the curative and preventative properties of crystals (talismans and amulets). Metals and trace elements are being used in some of today's most sophisticated medical applications. Other recent examples of beneficial effects of geologic materials and processes include epidemiological studies in Japan that have identified a wide range of health problems (such as muscle and joint pain, hemorrhoids, burns, gout, etc.) that may be treated by one or more of nine chemically distinct types of hot springs, and a study in China indicating that residential coal combustion may be mobilizing sufficient iodine to prevent iodine deficiency disease. ?? 2006 MDPI. All rights reserved.

Finkelman, R.B.

2006-01-01

276

Geology, geochemistry and geochronology of the Tamlalt-Menhouhou gold deposit (eastern High-Atlas)  

E-print Network

Geology, geochemistry and geochronology of the Tamlalt-Menhouhou gold deposit (eastern High-Atlas) The Tamlalt-Menhouhou gold deposit is located on the southern edge of the Neoprotérozoic-Palaeozoic Tamlalt Gold deposit" (IOCG) characterized by a strong sodic (± calcic) alteration and (ii) a secondary gold

Paris-Sud XI, Université de

277

Geologic evolution of Trail Ridge eolian heavy-mineral sand and underlying peat, northern Florida  

SciTech Connect

Trail Ridge ilmenite-ore sand is eolian in origin. Underlying freshwater-swamp peats are the same age, and sand impurities in peat record the approach of the dune. The original alteration state of detrital heavy minerals is preserved in the peat also. This book discusses the geologic evolution of Trail Ridge eolian heavy-mineral sand and underlying peat.

Force, E.R.; Rich, F.J.

1989-01-01

278

Montana Bureau of Mines and Geology  

NSDL National Science Digital Library

The Montana Bureau of Mines and Geology is the principal source of earth science information for the citizens of Montana. The bureau provides extensive advisory, technical, and informational services on geologic, mineral, energy, and water resources in the state of Montana. This includes earthquake studies, environmental assessment, Geographic Information Services (GIS), geology and minerals, groundwater, mines information, coal, state mapping, and more. The publications database contains all Bureau publications as well as U.S. Geological Survey publications related to Montana geology.

279

Geology Fieldnotes: Petrified Forest National Park, Arizona  

NSDL National Science Digital Library

Petrified Forest National Park was established to preserve large deposits of petrified wood and to prevent removal of the wood by the public. Site featues include park geology information, maps, photographs, related links, visitor information, multimedia resources, and resources for teaching geology with National Park examples. The park geology section discusses the park's geologic history, structural geology, petrified wood, and dinosaur fossils. The maps section includes a map of the park itself and the surrounding area.

280

Oregon Department of Geology and Mineral Industries  

NSDL National Science Digital Library

The Oregon Department of Geology and Mineral Industries brings geologic information about the state of Oregon to the public. Topics covered include general geology of Oregon, fossils, earthquakes, volcanoes, landslides, gems and minerals, and debris flows. Details about mined land reclamation and oil, gas, and geothermal projects are given. Oregon Geology magazine's latest issue is available to download, as well as general Northwest geology data.

281

The Necessity of Geologic Disposal  

SciTech Connect

Nuclear wastes are the radioactive byproducts of nuclear power generation, nuclear weapons production, and other uses of nuclear material. Experts from around the world agree that deep geologic disposal of nuclear waste in a mined repository is the most environmentally sound means of removing these potential sources of radiation from interaction with the biosphere. Of the 360 millirem of background radiation received annually by the average American, from both natural and man-made sources, less than 1 millirem results from the nuclear fuel cycle. Spent nuclear fuel and high-level radioactive waste, destined for geologic disposal, are located at 126 sites in 39 states. The proposed repository site at Yucca Mountain, Nevada, is far more isolated from the general population than any sites where these radioactive materials are presently located. Only solid forms of high-level wastes will be transported for disposal in a geologic repository. For more than 50 years, nuclear materials have been safely transported in North America, Europe, and Asia, without a single significant radiation release. Since the 1950s, select panels from the National Academy of Sciences-National Research Council and interagency advisory groups, and international experts selected by the OECD/Nuclear Energy Agency, have examined the environmental, ethical, and intergenerational aspects of nuclear waste disposal, plus alternatives to geologic disposal. All have concluded that deep geologic disposal in a mined repository is clearly the preferred option. The concept of deep geologic disposal is based on the analogy to ore deposits, which are formed deep within the Earth's crust, commonly remain isolated from the biosphere for millions to billions of years, and are, generally, extremely difficult to detect. Before selecting the unsaturated tuffs at Yucca Mountain, DOE evaluated salt formations, basalts, and both crystalline and sedimentary rocks. Other nations generating nuclear power also plan to use deep geologic disposal, and are evaluating sites in granites, argillaceous rocks, and salt formations.

R. Linden

2004-07-01

282

Geological myths and reality  

NASA Astrophysics Data System (ADS)

Myths are the result of man's attempts to explain noteworthy features of his environment stemming from unfounded imagination. It is unbelievable that in 21st century the explanation of evident lithospheric plates movements and origin of forces causing this movement is still bound to myths, They are the myth about mantle convection, myth about Earth's expansion, myth about mantle heterogeneities causing the movement of plates and myth about mantle plumes. From 1971 to 1978 I performed extensive study (Ost?ihanský 1980) about the terrestrial heat flow and radioactive heat production of batholiths in the Bohemian Massive (Czech Republic). The result, gained by extrapolation of the heat flow and heat production relationship, revealed the very low heat flow from the mantle 17.7mW m-2 close to the site of the Quarterly volcano active only 115,000 - 15,000 years ago and its last outbreak happened during Holocene that is less than 10,000 years ago. This volcano Komorní H?rka (Kammerbühls) was known by J. W. Goethe investigation and the digging of 300 m long gallery in the first half of XIX century to reach the basaltic plug and to confirm the Stromboli type volcano. In this way the 19th century myth of neptunists that basalt was a sedimentary deposit was disproved in spite that famous poet and scientist J.W.Goethe inclined to neptunists. For me the result of very low heat flow and the vicinity of almost recent volcanoes in the Bohemian Massive meant that I refused the hypothesis of mantle convection and I focused my investigation to external forces of tides and solar heat, which evoke volcanic effects, earthquakes and the plate movement. To disclose reality it is necessary to present calculation of acting forces using correct mechanism of their action taking into account tectonic characteristics of geologic unites as the wrench tectonics and the tectonic of planets and satellites of the solar system, realizing an exceptional behavior of the Earth as quickly rotating body exposed to strong tidal action of Moon and Sun. Ostrihansky, L.: The structure of the earth's crust and the heat-flow--heat-generation relationship in the Bohemian Massif. Tectonophysics, 68(3-4), 325-337, doi:10.1016/0040-1951(80)90182-1 1980.

Ostrihansky, Lubor

2014-05-01

283

Illinois State Geological Survey: Teacher Resources for Geology  

NSDL National Science Digital Library

The Illinois State Geological Survey (ISGS) has worked hard to create this vast array of materials designed for teachers working in geology and the earth sciences. The site is divided into two primary areas: "ISGS Teacher Resources" and "Other Teacher Resources." The "Ask An Expert" section is a good place to start, and it contains an A to Z archive of questions (and answers) that have been posed so far. Visitors are welcome to explore topics here like isotope geochemistry, limestone petrography, and also "Gold in Illinois." Also, this area contains links to teaching geology, which are quite useful. The "Other Teacher Resources" area brings together links to germane sites, such as the Denver Earth Science Project, NASA's meteorology home page, and online guides to landforms from the U.S. Bureau of Land Management.

284

Geologic Sequestration of Carbon Dioxide  

NASA Astrophysics Data System (ADS)

Geologic sequestration of carbon dioxide has emerged as one of the most promising options for making deep cuts in carbon dioxide emissions. Geologic sequestration involves the two-step process of first capturing carbon dioxide by separating it from stack emissions, followed by injection and long term storage in deep geologic formations. Sedimentary basins, including depleted oil and gas reservoirs, deep unminable coal seams, and brine-filled formations, provide the most attractive storage reservoirs. Over the past few years significant advances have been made in this technology, including development of simulation models and monitoring systems, implementation of commercial scale demonstration projects, and investigation of natural and industrial analogues for geologic storage of carbon dioxide. While much has been accomplished in a short time, there are many questions that must be answered before this technology can be employed on the scale needed to make significant reductions in carbon dioxide emissions. Questions such as how long must the carbon dioxide remain underground, to what extent will geochemical reactions completely immobilize the carbon dioxide, what can be done in the event that a storage site begins to leak at an unacceptable rate, what is the appropriate risk assessment, regulatory and legal framework, and will the public view this option favorably? This paper will present recent advances in the scientific and technological underpinnings of geologic sequestration and identify areas where additional information is needed.

Benson, S. M.

2003-04-01

285

Alteration mapping at Goldfield, Nevada, by cluster and discriminant analysis of Landsat digital data. [mapping of hydrothermally altered volcanic rocks  

NASA Technical Reports Server (NTRS)

The ability of Landsat multispectral digital data to differentiate among 62 combinations of rock and alteration types at the Goldfield mining district of Western Nevada was investigated by using statistical techniques of cluster and discriminant analysis. Multivariate discriminant analysis was not effective in classifying each of the 62 groups, with classification results essentially the same whether data of four channels alone or combined with six ratios of channels were used. Bivariate plots of group means revealed a cluster of three groups including mill tailings, basalt and all other rock and alteration types. Automatic hierarchical clustering based on the fourth dimensional Mahalanobis distance between group means of 30 groups having five or more samples was performed using Johnson's HICLUS program. The results of the cluster analysis revealed hierarchies of mill tailings vs. natural materials, basalt vs. non-basalt, highly reflectant rocks vs. other rocks and exclusively unaltered rocks vs. predominantly altered rocks. The hierarchies were used to determine the order in which sets of multiple discriminant analyses were to be performed and the resulting discriminant functions were used to produce a map of geology and alteration which has an overall accuracy of 70 percent for discriminating exclusively altered rocks from predominantly altered rocks.

Ballew, G.

1977-01-01

286

Pattern Alteration: Even Hip Circumference  

E-print Network

Even Hip Circumference Extension Family Development and Resource Management Specialists B Pattern Alteration E-386 05-06 efore attempting this alteration, review Extension publications E-372, Principles of Pattern Alteration, and E-373, Personal... Measurement Chart, for basic instruc- tions. Even Hip Circumference shows how to alter garments to fi t a fi gure with even hips. If only certain areas of the gar- ment are tight or loose, you may need different instructions. Review E-374, Back Hip Fullness...

2006-08-04

287

Physical Geology: Idaho Field Trip  

NSDL National Science Digital Library

This optional field trip is designed to augment the in-class learning experience in introductory physical geology by providing students the opportunity to see firsthand local geological features and understand their context in the long-term tectonic evolution of the western United States. The university is conveniently located in a portion of the American west where a plethora of geological features are readily accessible over a total field trip duration of 6 hours. Over a total of 6 field stops, students are presented with an opportunity to observe features relevant to topics learned in class involving rock types, volcanic features (lava flows and ash fall deposits), faults and folds, mass wasting features, catastrophic flood deposits (Bonneville and Missoula floods), and loess deposits.

Simon Kattenhorn

288

Bedrock Geologic Map of Maine  

NSDL National Science Digital Library

In this activity students study a map of bedrock geology which describes the types of rocks that exist in a given area. It shows these rock units as well as their known and inferred contacts. Consideration is also given to folding, faulting, unconformities, and similar rock relationships. These features are often included in bedrock geology maps. Students study the legend and scale and become aware of the other information that is included on the map such as the stratigraphic column, list of formations, and inset map of metamorphic grade. Students then locate their city or town and draw a 40-mile diameter circle around it and identify all the symbols inside the circle and the age of the various rocks. Student question sheets are available at this site. Although this activity was written for a map of Maine, it will work in any state where geological maps are available.

289

Geologic application of thermal inertia imaging using HCMM data  

NASA Technical Reports Server (NTRS)

The feasibility of using thermal inertia, inferred from remotely sensed temperature data, to complement LANDSAT reflectivity data for reconnaissance geologic mapping and mineral exploration is under investigation. The bulk of HCMM data tapes was received and processed, and a thermal inertia image of one data set was made. Additional areas of interest were identified on the HCMM photographic products and data tapes were ordered for these areas. During analysis of selected subareas, various sedimentary rock units were distinguished in the Death Valley, California test site and areas of altered rock were identified in the Cuprite/Goldifield, Nevada test site.

Paley, H. N.; Kahle, A. B. (principal investigators)

1980-01-01

290

Genetically Altered Plant Species  

NASA Technical Reports Server (NTRS)

Researchers in Robert Ferl's lab at the University of Florida in Gainesville, genetically altered this Arabdopsis Thaliana (a brassica species) plant to learn how extreme environments, such as the low atmospheric pressure on Mars, affect plant genes. They inserted green fluorescent protein (GFP) near the on/off switches for anoxia and drought genes. When those genes were turned on after exposure to reduced atmospheric pressure, GFP was turned on as well, causing cells expressing those genes to glow green under a blue light. The natural fluorescence of chlorophyll accounts for the red glow.

2003-01-01

291

Pattern Alteration: Lengthening & Shortening  

E-print Network

, and E-373, Personal Measurement Chart, for basic alteration instructions. A garment needs lengthening if major fi tting points, such as the waist or hem line ride up evenly around the body or fall too short for comfort. You might also want... to lengthen it because of personal preference or fashion. Short- ening is needed if major fi tting points are too long and/or extra crosswise folds appear evenly around the body. Lengthening or shortening a pattern is often the only adjustment you need...

2006-08-04

292

Society for Sedimentary Geology (SEPM)  

NSDL National Science Digital Library

The Society for Sedimentary Geology (SEPM) "is dedicated to the dissemination of scientific information on sedimentology, stratigraphy, paleontology, environmental sciences, marine geology, hydrogeology, and many additional related specialties." The website presents the latest and upcoming meetings, workshops, and other events. Individuals can find newsletters of the many SEPM sections and information on publications. Users can learn about the scientific achievements of many geologists in the Awards & Metals link. Students and researchers can discover the benefits of a SEPM membership including short courses and field trip opportunities.

293

Nevada Bureau of Mines and Geology  

NSDL National Science Digital Library

The Nevada Bureau of Mines and Geology (NBMG) is a research unit of the Mackay School of Mines at the University of Nevada, Reno and is the state geological survey. Scientists at NBMG conduct research and publish reports on mineral resources and various aspects of general, environmental, and engineering geology for the state of Nevada. There are on-line publications available to download, geologic maps, K-12 educational resources for teaching about Nevada geology, and a photo and image archive of the state. Links are provided for further information about the state and general geology resources.

294

Geology 106 Environmental Geology Schedule Spring 2009 MWF  

E-print Network

12 Geology and Stream Chemistry MF Apr 1317 Alternative Energy Water Pollution 13 Water/Wastewater Treatment, Text p. 388392 MF Apr 2024 Test Monday through Alt Energy Water Pollution Air Pollution Movement Waste Disposal p. 372389 7 Landfill MF Mar 26 Test Monday through Mass Movement Water

Kirby, Carl S.

295

Soil-plant-microbial relations in hydrothermally altered soils of Northern California  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soils developed on relict hydrothermally altered soils throughout the Western United States present unique opportunities to study the role of geology on above and belowground biotic activity and composition. Soil and vegetation samples were taken at three unaltered andesite and three hydrothermally ...

296

Petroleum geology of East Siberia  

Microsoft Academic Search

The unmetamorphosed geologic section of the East Siberian region consists of upper Proterozoic clastic and carbonate sediments; Cambrian evaporites, carbonates, and black shales; Ordovician to permian clastic and carbonate sediments; Triassic basaltic flows and intrusives; and Jurassic and Cretaceous clastic sediments. During the Cambrian, a barrier reef extended across the region. Salt and anhydrite were deposited in the vast lagoon

1986-01-01

297

Natural Selection and Geology 230  

E-print Network

;Natural Selection · The theory of natural selection was proposed by Charles Darwin in 1859, in his bookNatural Selection and Evolution Geology 230 Fossils and Evolution #12;The Study of Evolution the same theory as Darwin in the 1850s. #12;One of the most famous and influential books of science. #12

Kammer, Thomas

298

Historical Geology Online Laboratory Manual  

NSDL National Science Digital Library

The laboratories in this manual cover the following topics: rocks and minerals, weathering of rocks and the formation of sediment, sedimentary rocks and structures, depositional sedimentary environments, sand sieve analysis, relative dating, stratigraphy and lithologic correlation, fossils on the Internet, invertebrate macrofossils, microfossils, preservation, biostratigraphy, evolution, vertebrate paleontology, and interpreting geologic history from maps.

Pamela Gore

1982-01-01

299

Dr. Bob's Geologic Time Page  

NSDL National Science Digital Library

This is a collection of mnemonic devices to aid in learning the various periods and epochs of the geologic time scale which the author has assembled from a variety of contributors. Contributor email addresses are included. There are also mnemonic devices for Moh's hardness scale and for stratigraphic sequences from the Canyonlands-San Juan River area and the Grand Canyon.

Jorstad, Bob

2001-05-14

300

A Nontraditional Geology Field Trip.  

ERIC Educational Resources Information Center

Describes the design and logistics of a one-month, 1600 km bicycle tour field trip in which the travel, not the stops, is the major teaching tool. Provides a map and a summarized itinerary of the geology experience of southern California and Nevada. (RT)

Locke, William Willard

1989-01-01

301

National Park Service Geologic Resources  

NSDL National Science Digital Library

This collection of images shows geologic features in many of the country's national parks. The collection is searchable by park name, state, year, or by the name of the photograph. Each photo is accompanied by a brief caption that provides the photographer's name, the date, and a description of the photo.

302

Geological rhythms and cometary impacts  

NASA Technical Reports Server (NTRS)

Time series analysis reveals two dominant, long-term periodicities approximately equal to 32 and 260 million years in the known series of geological and biological upheavals during the Phanerozoic Eon. The cycles of these episodes agree in period and phase with the cycles of impact cratering on Earth, suggesting that periodic comet impacts strongly influence Earth processes.

Rampino, M. R.; Strothers, R. B.

1984-01-01

303

Report on geologic exploration activities  

Microsoft Academic Search

This report provides an overview of the geological exploration activities being carried out as part of the National Waste Terminal Storage (NWTS) Program, which has been established by the US Department of Energy (DOE) to develop the technology and provide the facilities for the safe, environmentally acceptable isolation of civilian high-level and transuranic nuclear wastes, including spent fuel elements, for

J. Breslin; R. B. Laughon; R. J. Hall; J. W. Voss

1980-01-01

304

Geologic exploration of solar system  

Microsoft Academic Search

The processes that must have operated on the early Earth have been deduced from evidence from ancient surfaces of the Moon and planets. In particular, such comparative studies have demonstrated that only two geologic processes have been widespread throughout the history of the solar system: impact cratering and volcanism. Impact craters have formed throughout solar system history, indeed the planets

Wood

1987-01-01

305

Earth System 1: Geological Environment  

NSDL National Science Digital Library

A Geological Sciences 100 lecture available here covers the basics of folding, rock deformation, stress and strain, and strike and dip, with many related images and diagrams. The lecture was made available by the Ohio State University's School of Earth Sciences.

306

US Geological Survey Fact Sheets  

NSDL National Science Digital Library

The US Geological Survey (USGS) Fact Sheets Web site summarizes research and investigations done by the agency and provides details about particular activities. The sheets are organized by theme, including resources, hazards, environment, information management, by individual state, and by scientific discipline. The fact sheets give basic summations of the research and provide links to more detailed pages for those seeking further information.

307

Briefing on geological sequestration (Tulsa)  

EPA Science Inventory

Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media ? primarily saline formations, depleted or nearly depleted oil and gas...

308

GEOLOGY, December 2007 1087 INTRODUCTION  

E-print Network

is followed by localized seafloor spreading at mid-ocean ridges (MOR), which are consid- ered, on geological of seafloor spreading in the North Atlantic. The data show that the initiation of magmatic seafloor spreading magnetic anomalies, the age of final breakup and the onset of seafloor spreading between Iberia

Hemming, Sidney R

309

Weird Geology: The Devil's Tower  

NSDL National Science Digital Library

This page features a brief introduction to the several theories about the geological processes that formed Devil's Tower, which rises 1,267 feet above the nearby Belle Fourche River and is still considered a sacred place by some Native American Tribes. Information on climbing the tower as well as images and a cross section are provided.

Krystek, Lee; Mystery, The M.

310

Infrared Analysis of Geological Materials.  

ERIC Educational Resources Information Center

Describes the infrared analysis of geological specimens which can form the basis of a laboratory exercise, allowing some minerals to be identified by "fingerprint" technique. Students can gain insight into the concept of symmetry and environment around an atom. (Author/SA)

Brown, Alan; Clark, E. Roy

1980-01-01

311

GEOLOGY, September 2010 823 INTRODUCTION  

E-print Network

numerical models constrained by global positioning system (GPS) observations and Geology, September 2010; v of dynamic modeling of the western Mediterranean that accounts for observed global positioning system (GPS External zone AH eq NUBIAN Rif Major thrust faults 4 5 6 Spain Med. sea Mo Figure 1. Global positioning

Demouchy, Sylvie

312

GEOLOGY, December 2011 1127 INTRODUCTION  

E-print Network

= = ( ) 1 , , (1) where Ti is the temperature of the ith compo- nent and fi is the fraction of the sensor that an uncertainty of ±0.2 in emissivity translates into only ±15 °C in pixel integrated temperatures, whileGEOLOGY, December 2011 1127 INTRODUCTION The surface temperature distribution of an active lava

Wright, Robert

313

The Geology of the Terrestrial Planets  

NASA Technical Reports Server (NTRS)

The geologic history of the terrestrial planets is outlined in light of recent exploration and the revolution in geologic thinking. Among the topics considered are planet formation; planetary craters, basins, and general surface characteristics; tectonics; planetary atmospheres; and volcanism.

Carr, M. H. (editor); Saunders, R. S.; Strom, R. G.; Wilhelms, D. E.

1984-01-01

314

Geology, Environmental Science, Geography, Environmental Management  

E-print Network

2011 Geology, Environmental Science, Geography, Environmental Management Postgraduate Handbook #12 Environmental Management 14 Environmental Science 18 Geography 22 Geographic Information Science 26 Geology, Environmental Science, Geography, Environmental Management Postgraduate Handbook Editors David Hayward, Ilse

Goodman, James R.

315

Geological Society of America Special Paper 365  

E-print Network

Geological Society of America Special Paper 365 2002 251 Stratigraphic record of Pleistocene of the Southwestern United States: Boulder, Colorado, Geological Society of America Special Paper 365, p. 251­269. *E

Dorsey, Becky

316

Geological Society of America Special Paper 365  

E-print Network

Geological Society of America Special Paper 365 2002 279 Convergence, block rotation of the Southwestern United States: Boulder, Colorado, Geological Society of America Special Paper 365, p. 279­293. *E

Kurapov, Alexander

317

Extreme Events in the Geological Past  

Microsoft Academic Search

Many Xevents in the geological past exceeded the strengths and intensities observed for modern-day natural events. The number\\u000a of extraordinary events that occurred in the geological past is of course much larger than the number we witness today because\\u000a the geological timescale covers millions of years. This contribution focuses on these Xevents from earth’s geological history,\\u000a including selected examples from

Jürgen Herget

318

Tour of Park Geology: Oldest Rocks  

NSDL National Science Digital Library

This park geology site provides links to tours of individual National Parks, Monuments, and Recreation Areas with the oldest known rocks. The parks are divided at this site into East and West. Where appropriate, for each park, links are provided to park geology, maps, photographs, geologic research, visitor information, multimedia resources, and teacher features (resources for teaching geology using National Park examples). Parks listed include: Voyaguers National Park, Keweenaw National Historic Park, Lake Meade National Recreation Area, and many more.

319

Altered fingerprints: analysis and detection.  

PubMed

The widespread deployment of Automated Fingerprint Identification Systems (AFIS) in law enforcement and border control applications has heightened the need for ensuring that these systems are not compromised. While several issues related to fingerprint system security have been investigated, including the use of fake fingerprints for masquerading identity, the problem of fingerprint alteration or obfuscation has received very little attention. Fingerprint obfuscation refers to the deliberate alteration of the fingerprint pattern by an individual for the purpose of masking his identity. Several cases of fingerprint obfuscation have been reported in the press. Fingerprint image quality assessment software (e.g., NFIQ) cannot always detect altered fingerprints since the implicit image quality due to alteration may not change significantly. The main contributions of this paper are: 1) compiling case studies of incidents where individuals were found to have altered their fingerprints for circumventing AFIS, 2) investigating the impact of fingerprint alteration on the accuracy of a commercial fingerprint matcher, 3) classifying the alterations into three major categories and suggesting possible countermeasures, 4) developing a technique to automatically detect altered fingerprints based on analyzing orientation field and minutiae distribution, and 5) evaluating the proposed technique and the NFIQ algorithm on a large database of altered fingerprints provided by a law enforcement agency. Experimental results show the feasibility of the proposed approach in detecting altered fingerprints and highlight the need to further pursue this problem. PMID:21808092

Yoon, Soweon; Feng, Jianjiang; Jain, Anil K

2012-03-01

320

Geology and Geohazards in Taiwan Geologic Field Course and Study Abroad Experience  

E-print Network

Geology and Geohazards in Taiwan Geologic Field Course and Study Abroad Experience Winter Break 2015 Interested in field geology? Interested in environmental hazards and climate? Want to visit #12;Geology and Geohazards in Taiwan This is a 3-week course for students interested in mixing field

Alpay, S. Pamir

321

Courses: Geology (GEOL) Page 325Sonoma State University 2014-2015 Catalog Geology (GEOL)  

E-print Network

Courses: Geology (GEOL) Page 325Sonoma State University 2014-2015 Catalog Geology (GEOL) geoL 102 our dynAMiC eArtH: introduCtion to geoLogy (3) Lecture, 2 hours; laboratory, 3 hours. A study. Empha- sis on local geology, including earthquakes and other environmental aspects. Labo- ratory study

Ravikumar, B.

322

Mathematical Geology, Vol. 34, No. 1, January 2002 ( C 2002) On Modelling Discrete Geological Structures  

E-print Network

Mathematical Geology, Vol. 34, No. 1, January 2002 ( C 2002) On Modelling Discrete Geological there is a large amount of missing observations, which often is the case in geological applications. We make,predictions,MarkovchainMonteCarlo,simulatedannealing,incomplete observations. INTRODUCTION In many geological applications, there is an interest in predicting properties

Baran, Sándor

323

Remote sensing, geology, and land use  

NASA Technical Reports Server (NTRS)

The usefulness of a geologic map as a product in geological research was discussed, and the volution of the geologic map of Maryland was illustrated. Remote sensing methods that have the most immediate application to the earth science aspects of the Chesapeake Bay region are listed.

Weaver, K. N.

1978-01-01

324

Where Can aWhere Can a Geology/Geophysics DegreeGeology/Geophysics DegreeGeology/Geophysics DegreeGeology/Geophysics Degree  

E-print Network

, Physics, Geology)Geology) ·· Teacher training program emphasizingTeacher training program emphasizing·· Teacher training program emphasizingTeacher training program emphasizing classroom managementclassroomGeology/Geophysics Degree Take You?Take You? PresenterPresenter Abel Vanegas 8th Grade Physical Science Teacher Riverview

Militzer, Burkhard

325

Learning Geologic Time in the Field.  

ERIC Educational Resources Information Center

Describes a method used to teach the concept of geologic time to introductory geology students using an inquiry-based approach. Students work in teams to obtain rock samples that are used to interpret the geologic history of a region. (SAH)

Thomas, Robert C.

2001-01-01

326

Sedimentary RocksSedimentary Rocks Geology 200  

E-print Network

Sedimentary RocksSedimentary Rocks Geology 200 Geology for Environmental ScientistsGeology for Environmental Scientists #12;Major Concepts · Sedimentary rocks form by the processes of weathering, erosion · Sedimentary structures are critical to interpreting sedimentary rocks. #12;The Rock CycleThe Rock Cycle #12

Kammer, Thomas

327

Physical Geology Notes and Visual Aids  

NSDL National Science Digital Library

This site contains notes, graphics, presentations and slides for a variety of physical geology topics, including geologic maps, volcanoes, mass-wasting, ground water, landforms, rock types, fossils and evolution, glaciers, geologic time, erosion, metamorphism, earthquakes, plate tectonics, and Earth resources.

Dutch, Steve

328

Geological and geotechnical databases and developments  

E-print Network

Geological and geotechnical databases and developments in the Netherlands Robert Hack & Wiebke Tegtmeier Namur, Belgium, 9 October 2007 #12;9 October 2007 Geological and geotech databases in NL - Hack 2007 Geological and geotech databases in NL - Hack & Tegtmeier 3 Surface data: · Climate · Vegetation

Hack, Robert

329

Christopher U.S. Geological Survey  

E-print Network

(minor in Geology), The University of Arizona, Tucson, Arizona "Bedrock-controlled fluvial geomorphology desalinization loop in Chula Vista, California. Hydrologist U.S. Geological Survey, Tucson, Arizona. May 2000Christopher Magirl U.S. Geological Survey 934 Broadway Suite 300 Tacoma, Washington 98402 Phone

330

Geologic Diversity of Arizona and Its Margins;  

E-print Network

Geologic Diversity of Arizona and Its Margins; Excursions to Choice Areas Arizona Bureau of Geology Sandstones in SouthernUtah and Northern Arizona David M.Rubin and Ralph E.Hunter U.S. GeologicalSurvey Menio between the areas of Page, Arizona and St. George, Utah (figure I), but the sedimentarym c - tines

331

, UNIVERSITY Brigham Young University Geology Studies  

E-print Network

, UNIVERSITY #12;Brigham Young University Geology Studies Volume 1 5 - 1968 Part 2 Studies for Students No. 1 Guide to the Geology of the Wasatch Mountain Front, Between Provo Canyon and Y Mountain, Northeast of Provo, Utah by J. Keith Rigby and Lehi F. Hintze #12;A publication of the Department of Geology

Seamons, Kent E.

332

GeoloGy (Geol) Robinson Foundation  

E-print Network

182 GeoloGy (Geol) Robinson Foundation PROFESSOR HARBoR ASSOCIATE PROFESSORS KNAPP, CONNORS ASSISTANT PROFESSORS GREER, RAHL MAJORS BACHELOR OF SCIENCE Amajor in geology leading to a Bachelor of Science degree consists of 50 credits as follows: 1. Geology160,185,211,311,330,350,andacom- prehensive

Dresden, Gregory

333

U.S. Geological Survey: Coastal and Marine Geology Program  

NSDL National Science Digital Library

Geologists, meteorologists, disaster specialists and others will find much to engage their attention on this website. Created by the United States Geological Survey, this site provides succinct overviews of a range of topics from the National Coastal Program Plan to El Nino, erosion, and sea-level change. Teachers should click on the drop down Content Type menu to access the Educational Materials area. Here they will find over 100 resources that highlight ocean mapping projects, core geology work, and ocean acidification. Visitors may also browse through these resources looking for movies, maps, data sets, photographs, and more. Additionally, visitors can learn about the program's field centers, located in St. Petersburg, Woods Hole, and Menlo Park.

2012-02-28

334

Physical Geology Laboratory Manual Charles Merguerian and J Bret Bennington  

E-print Network

Physical Geology Laboratory Manual Charles Merguerian and J Bret Bennington Geology Department Hofstra University © 2006 #12;i PHYSICAL GEOLOGY LABORATORY MANUAL Ninth Edition Professors Charles Merguerian and J Bret Bennington Geology Department Hofstra University #12;ii ACKNOWLEDGEMENTS We thank

Merguerian, Charles

335

GeoSciML version 3: A GML application for geologic information  

NASA Astrophysics Data System (ADS)

After 2 years of testing and development, XML schema for GeoSciML version 3 are now ready for application deployment. GeoSciML draws from many geoscience data modelling efforts to establish a common suite of feature types to represent information associated with geologic maps (materials, structures, and geologic units) and observations including structure data, samples, and chemical analyses. After extensive testing and use case analysis, in December 2008 the CGI Interoperability Working Group (IWG) released GeoSciML 2.0 as an application schema for basic geological information. GeoSciML 2.0 is in use to deliver geologic data by the OneGeology Europe portal, the Geological Survey of Canada Groundwater Information Network (wet GIN), and the Auscope Mineral Resources portal. GeoSciML to version 3.0 is updated to OGC Geography Markup Language v3.2, re-engineered patterns for association of element values with controlled vocabulary concepts, incorporation of ISO19156 Observation and Measurement constructs for representing numeric and categorical values and for representing analytical data, incorporation of EarthResourceML to represent mineral occurrences and mines, incorporation of the GeoTime model to represent GSSP and stratigraphic time scale, and refactoring of the GeoSciML namespace to follow emerging ISO practices for decoupling of dependencies between standardized namespaces. These changes will make it easier for data providers to link to standard vocabulary and registry services. The depth and breadth of GeoSciML remains largely unchanged, covering the representation of geologic units, earth materials and geologic structures. ISO19156 elements and patterns are used to represent sampling features such as boreholes and rock samples, as well as geochemical and geochronologic measurements. Geologic structures include shear displacement structures (brittle faults and ductile shears), contacts, folds, foliations, lineations and structures with no preferred orientation (e.g. 'miarolitic cavities'). The Earth material package allows for the description of both individual components, such as minerals, and compound materials, such as rocks or unconsolidated materials. Provision is made for alteration, weathering, metamorphism, particle geometry, fabric, and petrophysical descriptions. Mapped features describe the shape of the geological features using standard GML geometries, such as polygons, lines, points or 3D volumes. Geological events provide the age, process and environment of formation of geological features. The Earth Resource section includes features to represent mineral occurrences and mines and associated human activities independently. This addition allows description of resources and reserves that can comply with national and internationally accepted reporting codes. GeoSciML v3 is under consideration as the data model for INSPIRE annex 2 geologic reporting in Europe.

International Union of Geological Sciences., I. C.; Richard, S. M.

2011-12-01

336

Aqueous Alteration of Basalts: Earth, Moon, and Mars  

NASA Technical Reports Server (NTRS)

The geologic processes responsible for aqueous alteration of basaltic materials on Mars are modeled beginning with our knowledge of analog processes on Earth, i.e., characterization of elemental and mineralogical compositions of terrestrial environments where the alteration and weathering pathways related to aqueous activity are better understood. A key ingredient to successful modeling of aqueous processes on Mars is identification of phases that have formed by those processes. The purpose of this paper is to describe what is known about the elemental and mineralogical composition of aqueous alteration products of basaltic materials on Mars and their implications for specific aqueous environments based upon our knowledge of terrestrial systems. Although aqueous alteration has not occurred on the Moon, it is crucial to understand the behaviors of basaltic materials exposed to aqueous environments in support of human exploration to the Moon over the next two decades. Several methods or indices have been used to evaluate the extent of basalt alteration/weathering based upon measurements made at Mars by the Mars Exploration Rover (MER) Moessbauer and Alpha Particle X-Ray Spectrometers. The Mineralogical Alteration Index (MAI) is based upon the percentage of total Fe (Fe(sub T)) present as Fe(3+) in alteration products (Morris et al., 2006). A second method is the evaluation of compositional trends to determine the extent to which elements have been removed from the host rock and the likely formation of secondary phases (Nesbitt and Young, 1992; Ming et al., 2007). Most of the basalts that have been altered by aqueous processes at the two MER landing sites in Gusev crater and on Meridiani Planum have not undergone extensive leaching in an open hydrolytic system with the exception of an outcrop in the Columbia Hills. The extent of aqueous alteration however ranges from relatively unaltered to pervasively altered materials. Several experimental studies have focused upon the aqueous alteration of lunar materials and simulants (e.g., Keller and Huang, 1971; Eick et al., 1996). Lunar basalts are void of water and highly reduced, hence, these materials are initially very reactive when exposed to water under oxidizing conditions.

Ming, Douglas W.

2007-01-01

337

MSc STUDY PROGRAMME IN THE FACULTY OF GEOLOGY AND GEOENVIRONMENT, UNIVERSITY OF ATHENS 201314 Geology and Geoenvironment  

E-print Network

MSc STUDY PROGRAMME IN THE FACULTY OF GEOLOGY AND GEOENVIRONMENT, UNIVERSITY OF ATHENS 201314 1 Geology and Geoenvironment MSc Programme STUDENT HANDBOOK Applied Environmental Geology, Stratigraphy Paleontology, Geography and Environment, Dynamic Geology and Tectonics/ Hydrogeology, Geophysics

Kouroupetroglou, Georgios

338

Boullier The fault zone geology 1 Fault zone geology: lessons from drilling through the Nojima and 1  

E-print Network

Boullier The fault zone geology 1 Fault zone geology: lessons from active faults with the aim of 11 learning about the geology of the fault all 18 their objectives, have still contributed to a better geological

Boyer, Edmond

339

Marine Geology: Research Beneath the Sea  

NSDL National Science Digital Library

Another informative offering from the US Geological Survey is the Marine Geology: Research Beneath the Sea Web site. Visitors can read about the agency's Marine Geology program which "strives to increase our understanding of the geology of the lands covered by water." Topics include methods and equipment used for the research, plate tectonics, resources in the marine realm, predicting effects of marine processes, new frontiers, and even images of marine geology. This interesting and unique site does a good job of explaining and educating the public on this important segment of the agency's research.

340

The Development of Geology in Serbia  

NASA Astrophysics Data System (ADS)

Geology in Serbia began to develop in the first half of the 19th century mainly for two reasons: the endeavours of Prince Miloš to expand the national economy (including mining) and the interest shown by European scientists for an unknown country. When in 1880 Jovan Žujovi? became the professor of geology and mineralogy at the High School in Belgrade, as the first Serbian geologist who studied in Belgrade and Paris, the development of geology in Serbia was strongly increased. Zujovic's successors: Sava Uroševi? (mineralogy, petrology), Svetolik Radovanovi? (palaeontology), Petar Pavlovi? (palaeontology), Vladimir Petkovi? (regional geology), Jelenko Mihailovi? (seismology) and others continued geological investigations in Serbia.

Jovic, V.

2008-10-01

341

Parasites alter community structure  

PubMed Central

Parasites often play an important role in modifying the physiology and behavior of their hosts and may, consequently, mediate the influence hosts have on other components of an ecological community. Along the northern Atlantic coast of North America, the dominant herbivorous snail Littorina littorea structures rocky intertidal communities through strong grazing pressure and is frequently parasitized by the digenean trematode Cryptocotyle lingua. We hypothesized that the effects of parasitism on host physiology would induce behavioral changes in L. littorea, which in turn would modulate L. littorea's influence on intertidal community composition. Specifically, we hypothesized that C. lingua infection would alter the grazing rate of L. littorea and, consequently, macroalgal communities would develop differently in the presence of infected versus uninfected snails. Our results show that uninfected snails consumed 40% more ephemeral macroalgal biomass than infected snails in the laboratory, probably because the digestive system of infected snails is compromised by C. lingua infection. In the field, this weaker grazing by infected snails resulted in significantly greater expansion of ephemeral macroalgal cover relative to grazing by uninfected snails. By decreasing the per-capita grazing rate of the dominant herbivore, C. lingua indirectly affects the composition of the macroalgal community and may in turn affect other species that depend on macroalgae for resources or habitat structure. In light of the abundance of parasites across systems, we suggest that, through trait-mediated indirect effects, parasites may be a common determinant of structure in ecological communities. PMID:17517667

Wood, Chelsea L.; Byers, James E.; Cottingham, Kathryn L.; Altman, Irit; Donahue, Megan J.; Blakeslee, April M. H.

2007-01-01

342

Geologic periodicities and the Galaxy  

NASA Technical Reports Server (NTRS)

New geologic and astronomical developments are reviewed that have recently led to the proposal of various Galactic theories to explain the temporal pattern of impact craters on earth. Linear and harmonic time series analyses have revealed that two dominant periodicities about equal to 33 + or - 3 Myr and 260 + or - 25 Myr underlie the geologic record of terrestrial impact cratering and global tectonic phenomena. It is argued that purely terrestrial mechanisms cannot account for the cratering cycles as being preservational artifacts; cratering rather appears to influence tectonism, possibly through perturbations of mantle convection. Galactic models proposed to explain the two long-term periodicities are reviewed critically. The most likely explanation for the 33 Myr cycle involves the comparatively stable half period of vertical oscillation of the solar system about the Galactic plane. The 260 Myr cycle may be related to rare encounters with Galactic spiral arms during the revolution of the solar system around the Galactic center.

Rampino, Michael R.; Stothers, Richard B.

1986-01-01

343

Computer image processing: Geologic applications  

NASA Technical Reports Server (NTRS)

Computer image processing of digital data was performed to support several geological studies. The specific goals were to: (1) relate the mineral content to the spectral reflectance of certain geologic materials, (2) determine the influence of environmental factors, such as atmosphere and vegetation, and (3) improve image processing techniques. For detection of spectral differences related to mineralogy, the technique of band ratioing was found to be the most useful. The influence of atmospheric scattering and methods to correct for the scattering were also studied. Two techniques were used to correct for atmospheric effects: (1) dark object subtraction, (2) normalization of use of ground spectral measurements. Of the two, the first technique proved to be the most successful for removing the effects of atmospheric scattering. A digital mosaic was produced from two side-lapping LANDSAT frames. The advantages were that the same enhancement algorithm can be applied to both frames, and there is no seam where the two images are joined.

Abrams, M. J.

1978-01-01

344

Geologic and Navajo Time Line  

NSDL National Science Digital Library

This lab serves to introduce students to geologic time and serves as an outline for the course through the semester. Students use a tape register and must mark out the corresponding length of each Geologic Era and Eon towards the beginning of the course. Above Western time line Navajo students construct their own time line correlating events as best as possible. As the course progresses starting from 4.6bya each week they must draw major events that occur marking correct subdivisions of time and ages ago. As fossil life gets more complex such as beginning in the Paleozoic students are must take different categories of fossils or different periods so all are doing different things but working together. (Similarly the Navajo time line builds. This time line is taped around the room---and I would have liked to paint the two time lines along the corridor of the building but Maintenance axed it.

Margaret Mayer

345

Geology of the reading prong  

SciTech Connect

For over a billion years the geological terrain now called New Jersey has been the site of unusually high uranium concentrations. Although the highest of these concentrations occurs in the Reading Prong, the area is itself only part of a larger geologic province extending to the northeast and southwest. The rocks in the Reading Prong are not uniformly radioactive. High uranium concentrations tend to be associated with magnetite deposits - metamorphic equivalents of iron-rich formations - and with pegmatites - rocks formed by precipitation from mineralizing solutions in the late phases of granite emplacement. Because of the way they were formed, the uranium-bearing magnetite and pegmatite bodies tend to be long and narrow, and the resulting patterns of radon occurrence can be expected to be the same. This may explain why, in some places, adjacent houses have very different radon concentrations.

Schutz, D.

1987-03-01

346

Shock compression of geological materials  

NASA Astrophysics Data System (ADS)

Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

Kirk, S.; Braithwaite, C.; Williamson, D.; Jardine, A.

2014-05-01

347

Fractals in geology and geophysics  

NASA Technical Reports Server (NTRS)

The definition of a fractal distribution is that the number of objects N with a characteristic size greater than r scales with the relation N of about r exp -D. The frequency-size distributions for islands, earthquakes, fragments, ore deposits, and oil fields often satisfy this relation. This application illustrates a fundamental aspect of fractal distributions, scale invariance. The requirement of an object to define a scale in photograhs of many geological features is one indication of the wide applicability of scale invariance to geological problems; scale invariance can lead to fractal clustering. Geophysical spectra can also be related to fractals; these are self-affine fractals rather than self-similar fractals. Examples include the earth's topography and geoid.

Turcotte, Donald L.

1989-01-01

348

Radioactive waste disposal and geology  

Microsoft Academic Search

This book is an excellent, well-presented treatise on the nature and types of radioactive wastes, disposal alternatives and strategies, radionuclide release and disposal models, geologic repositories, natural analogues, subsea-bed options, and low-level wastes. The authors provide national and international perspectives on radioactive waste disposal problems. They carefully dissected each issue, treating its pros and cons equally. Moreover, they is careful

K. B. Krauskopf

1988-01-01

349

Geological exploration from orbital altitudes  

USGS Publications Warehouse

The National Aeronautics & Space Administration is planning geologic exploration from orbiting spacecraft. For that purpose it is evaluating new and refined exploration tools, often called remote sensors, including devices that are sensitive to force fields, such as gravity gradient systems, and devices that record the reflection or emission of electromagnetic energy. Both passive electromagnetic sensors (those that rely on natural sources of illumination, such as the Sun) and active electromagnetic sensors (which use an artificial source of illumination) are being considered.

Badgley, Peter C.; Fischer, William A.; Lyon, Ronald J.P.

1965-01-01

350

Perkins Geology Museum Digital Archive  

NSDL National Science Digital Library

This online database contains thousands of digital images from the collections of the University of Vermont's Perkins Geology Museum. The collection emphasizes material from Vermont, but it also includes rock and mineral specimens, maps, slides, thin sections, and photographs from around the world. It can be browsed by type (rocks, minerals, fossils, or thin sections) or searched by keyword and locality. Each image is accompanied by brief metadata, including title, file name and catalog number, image resolution, and locality (where available).

351

Dione's spectral and geological properties  

USGS Publications Warehouse

We present a detailed analysis of the variations in spectral properties across the surface of Saturn's satellite Dione using Cassini/VIMS data and their relationships to geological and/or morphological characteristics as seen in the Cassini/ISS images. This analysis focuses on a local region on Dione's anti-saturnian hemisphere that was observed by VIMS with high spatial resolution during orbit 16 in October 2005. The results are incorporated into a global context provided by VIMS data acquired within Cassini's first 50 orbits. Our results show that Dione's surface is dominated by at least one global process. Bombardment by magnetospheric particles is consistent with the concentration of dark material and enhanced CO2 absorption on the trailing hemisphere of Dione independent of the geology. Local regions within this terrain indicate a special kind of resurfacing that probably is related to large-scale impact process. In contrast, the enhanced ice signature on the leading side is associated with the extended ejecta of the fresh impact crater Creusa (???49??N/76??W). Although no geologically active regions could be identified, Dione's tectonized regions observed with high spatial resolution partly show some clean H2O ice implying that tectonic processes could have continued into more recent times. ?? 2009 Elsevier Inc. All rights reserved.

Stephan, K.; Jaumann, R.; Wagner, R.; Clark, R.N.; Cruikshank, D.P.; Hibbitts, C.A.; Roatsch, T.; Hoffmann, H.; Brown, R.H.; Filiacchione, G.; Buratti, B.J.; Hansen, G.B.; McCord, T.B.; Nicholson, P.D.; Baines, K.H.

2010-01-01

352

U. S. Geological Survey Library  

NSDL National Science Digital Library

The United States Geological Survey (USGS) Library is the largest earth science library in the world. The library serves the research needs of USGS scientists throughout the nation and provides information to other organizations and individuals in the areas of geology, hydrology, cartography, biology, and related fields. USGS libraries are located in Reston, Virginia, Denver, Colorado, Menlo Park, California, and Flagstaff, Arizona. Some of the library holdings are available on-line, while others can be purchased from USGS, ordered via an interlibrary loan, or attained from one of the four library locations directly. The library home page provides links to search engines for USGS publications, photographs, maps, etc. Users can search various databases to find what they need. These databases include: the Geographic Names Information System database, the Minerals Information Collection, the National Geologic Map Database, and a database of purchased journals held by the library. Users can also search the library's catalog, and can post questions to a librarian via the Ask a Librarian link.

353

ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS  

SciTech Connect

Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

A.P. Deditius; S. Utsunomiya; R.C. Ewing

2006-02-21

354

Ageismus – Sprachliche Diskriminierung des Alters  

Microsoft Academic Search

Daniel Sanders, einer der bedeutendsten Lexikografen des 19. Jahrhunderts, wertete für sein Wörterbuch Quellen seit der Lutherzeit aus und\\u000a vermerkt im Wörterbuchartikel zu alt eine „bald lobende, bald tadelnde“ Bedeutung des Adjektivs. Sein Zeit- und Berufsgenosse Jacob Grimm benennt in seiner Rede über das Alter die zeitgenössischen Synonyme zu alt und Alter: „aus einheimischen schriftstellern liesze sich eine lange reihe

Undine Kramer

355

Epigenetic alterations in gastric carcinogenesis  

Microsoft Academic Search

Gastric cancer is believed to result in part from the accumulation of multiple genetic alterations leading to oncogene overexpression and tumor suppressor loss. Epigenetic alterations as a distinct and crucial mechanism to silence a variety of methylated tissue-specific and imprinted genes, have been extensively studied in gastric carcinoma and play important roles in gastric carcinogenesis. This review will briefly discuss

In-Seon CHOI; Tsung-Teh WU

2005-01-01

356

B.S. GEOLOGY (Geology Subplan) CHECKLIST of required courses for major Geology Core Courses: 9-10 courses, 33-34 credits  

E-print Network

B.S. GEOLOGY (Geology Subplan) CHECKLIST of required courses for major Geology Core Courses: 9 - Experiencing Geology Lab and either GEOSCI 103 - Intro to Oceanography or GEOSCI 105 - Dynamic Earth 4 (1) (4 semester GEOSCI 201 ­ History of the Earth 4 1st or 2nd year, spring semester GEOSCI 231 ­ Geological Field

Massachusetts at Amherst, University of

357

Preliminary Geologic Characterization of West Coast States for Geologic Sequestration  

SciTech Connect

Characterization of geological sinks for sequestration of CO{sub 2} in California, Nevada, Oregon, and Washington was carried out as part of Phase I of the West Coast Regional Carbon Sequestration Partnership (WESTCARB) project. Results show that there are geologic storage opportunities in the region within each of the following major technology areas: saline formations, oil and gas reservoirs, and coal beds. The work focused on sedimentary basins as the initial most-promising targets for geologic sequestration. Geographical Information System (GIS) layers showing sedimentary basins and oil, gas, and coal fields in those basins were developed. The GIS layers were attributed with information on the subsurface, including sediment thickness, presence and depth of porous and permeable sandstones, and, where available, reservoir properties. California offers outstanding sequestration opportunities because of its large capacity and the potential of value-added benefits from enhanced oil recovery (EOR) and enhanced gas recovery (EGR). The estimate for storage capacity of saline formations in the ten largest basins in California ranges from about 150 to about 500 Gt of CO{sub 2}, depending on assumptions about the fraction of the formations used and the fraction of the pore volume filled with separate-phase CO{sub 2}. Potential CO{sub 2}-EOR storage was estimated to be 3.4 Gt, based on a screening of reservoirs using depth, an API gravity cutoff, and cumulative oil produced. The cumulative production from gas reservoirs (screened by depth) suggests a CO{sub 2} storage capacity of 1.7 Gt. In Oregon and Washington, sedimentary basins along the coast also offer sequestration opportunities. Of particular interest is the Puget Trough Basin, which contains up to 1,130 m (3,700 ft) of unconsolidated sediments overlying up to 3,050 m (10,000 ft) of Tertiary sedimentary rocks. The Puget Trough Basin also contains deep coal formations, which are sequestration targets and may have potential for enhanced coal bed methane recovery (ECBM).

Larry Myer

2005-09-29

358

Geology of Mount Rainier National Park, Washington  

USGS Publications Warehouse

Mount Rainier National Park includes 378 square miles of rugged terrain on the west slope of the Cascade Mountains in central Washington. Its mast imposing topographic and geologic feature is glacier-clad Mount Rainier. This volcano, composed chiefly of flows of pyroxene andesite, was built upon alt earlier mountainous surface, carved from altered volcanic and sedimentary rocks invaded by plutonic and hypabyssal igneous rocks of great complexity. The oldest rocks in the park area are those that make up the Olmnapecosh Formation of late Eocene age. This formation is more than 10,000 feet thick, and consists almost entirely of volcanic debris. It includes some lensoid accumulations of lava and coarse mudflows, heaped around volcanic centers., but these are surrounded by vastly greater volumes of volcanic clastic rocks, in which beds of unstratified coarse tuff-breccia, about 30 feet in average thickness, alternate with thin-bedded breccias, sandstones, and siltstones composed entirely of volcanic debris. The coarser tuff-breccias were probably deposited from subaqueous volcanic mudflows generated when eruption clouds were discharged directly into water, or when subaerial ash flows and mudflows entered bodies of water. The less mobile mudflows and viscous lavas built islands surrounded by this sea of thinner bedded water-laid clastics. In compostion the lava flows and coarse lava fragments of the Ohanapecosh Formation are mostly andesite, but they include less abundant dacite, basalt, and rhyolite. The Ohanapecosh Formation was folded, regionally altered to minerals characteristic of the zeolite facies of metamorphism, uplifted, and deeply eroded before the overlying Stevens Ridge Formation of Oligocene or early Miocene age was deposited upon it. The Stevens Ridge rocks, which are about 3,000 feet in maximum total thickness, consist mainly of massive ash flows. These are now devitrified and altered, but they originally consisted of rhyodacite pumice lapilli and glass shards, which compacted and welded into thick massive units during emplacement and cooling. Subordinate water-laid clastic rocks occur t(ward the top of the formation, and thin-bedded pyroclastic layers occur between some of the ash flows. Exposures on Backbone Ridge and on Carbon River below the mouth of Cataract Creek show that in places the thick basal Stevens Ridge ash flows swept with great violence over an old erosion surface developed on rocks of the Ohanapecosh Formation. Masses of mud, tree trunks, and other surface debris were swirled upward into the base of the lowermost ash fiery, and lobes and tongues of hot ash were forced downward into. the saprolitic mud. The Stevens Ridge Formation is concordantly overlain by the Fifes Peak Formation of probable early Miocene age, which consists of lava flows, subordinate mudflows, and minor quantities of tuffaceous clastic rocks. The lavas are predominantly olivine basalt and basaltic andesite, but they include a little rhyolite. They are slightly to moderately altered: the ferromagnesian phenocrysts are generally replaced by saponite, chiprite, or carbonate ; the glass is devitrified ; and the rocks are locally permeated by veinlets of zeolite. Swarms of diabase sills and dikes are probably intrusive equivalents of the Fifes Peak lavas. The upper part of the Fifes Peak Formation has been mostly eroded from Mount Rainier National Park, but farther north, in the Cedar Lake quadrangle, it attains a thickness of more than 5,000 feet. The Fifes Peak and earlier formations were gently folded, faulted, uplifted, and eroded before the. late Miocene Tatoosh pluton worked its way upward to shallow depths and eventually broke through to the surface. The rise of the pluton was accompanied by .the injection of a complicated melange of satellitic stocks, sills, and dikes. A favored horizon for intrusion of sills was along or near the unconfo

Fiske, Richard S.; Hopson, Clifford Andrae; Waters, Aaron Clement

1963-01-01

359

International Geology Review, Vol. 46, 2004, p. XXXXXX. Copyright 2004 by V. H. Winston & Son, Inc. All rights reserved.  

E-print Network

from Bawshir, Northeastern Oman ALEY K. EL-SHAZLY Department of Geology, Geography, and Physics 551, PC 113, Muscat, Sultanate of Oman Abstract Several types of Ca-rich, metasomatically altered, west of Ruwi in northeastern Oman. Type A rodingites contain mainly hydrogarnet, with smaller amounts

El-Shazly, Aley

360

Medical Geology - Special Initiative of the International Union of Geological Scientists  

NSDL National Science Digital Library

This is the official home page of the International Working Group on Medical Geology, a special initiative of the International Union of Geological Sciences. The group was organized to improve communication among the various disciplines concerned with diseases caused by geological factors, as well as promote the development of educational materials, literature, and further research and programs that address the issue of medical geology. This site provides links to information about current research, meetings, and other activities of the International Medical Geology Association; books, reports, brochures and other literature for sale or download; membership opportunities and discussion groups; outreach and education; a glossary of medical, geological, chemical, and biological terms, and much more.

Geology, International W.

361

Bedrock geologic map of the Seward Peninsula, Alaska, and accompanying conodont data  

USGS Publications Warehouse

This 1:500,000-scale geologic map depicts the bedrock geology of Seward Peninsula, western Alaska, on the North American side of the Bering Strait. The map encompasses all of the Teller, Nome, Solomon, and Bendeleben 1:250,000-scale quadrangles, and parts of the Shishmaref, Kotzebue, Candle, and Norton Bay 1:250,000-scale quadrangles (sh. 1; sh. 2). The geologic map is presented on Sheet 1. The pamphlet includes an introductory text, detailed unit descriptions, tables of geochronologic data, and an appendix containing conodont (microfossil) data and a text explaining those data. Sheet 2 shows metamorphic and tectonic units, conodont color alteration indices, key metamorphic minerals, and locations of geochronology samples listed in the pamphlet. The map area covers 74,000 km2, an area slightly larger than West Virginia or Ireland.

Till, Alison B.; Dumoulin, Julie A.; Werdon, Melanie B.; Bleick, Heather A.

2011-01-01

362

Preliminary bedrock geologic map of the Seward Peninsula, Alaska, and accompanying conodont data  

USGS Publications Warehouse

This 1:500,000-scale geologic map depicts the bedrock geology of Seward Peninsula, western Alaska, on the North American side of the Bering Strait. The map encompasses all of the Teller, Nome, Solomon, and Bendeleben 1:250,000-scale quadrangles, and parts of the Shishmaref, Kotzebue, Candle, and Norton Bay 1:250,000-scale quadrangles (sheet 1; sheet 2). The geologic map is presented on Sheet 1. The pamphlet includes an introductory text, unit descriptions, tables of geochronologic data, and an appendix containing conodont (microfossil) data and a text about those data. Sheet 2 shows metamorphic and tectonic units, conodont color alteration indices, key metamorphic minerals, and locations of geochronology samples listed in the pamphlet.

Till, Alison B.; Dumoulin, Julie A.; Werdon, Melanie B.; Bleick, Heather A.

2010-01-01

363

Petroleum geology of southwestern Ohio  

SciTech Connect

Approximately 250 wells have been drilled in the 22-county area comprising southwestern Ohio. Despite numerous shows from various zones, no sustained commercial production has been established. Live oil and gas shows have been reported from surface exposures of outcropping Silurian carbonates down to, and including, the Cambrian Mount Simon Sandstone. Several wells have been completed and actually produced hydrocarbons for a short period, but were subsequently abandoned. Despite the lack of established production, the area holds considerable promise as a potential oil and natural gas producing region. Gravity, magnetics, seismic, surface and source rock geochemistry, linear trace analysis, and subsurface computer mapping have all been used to study the structure, stratigraphy, and petroleum geology of the area. Basement geology is complex and has affected sedimentation patterns in the overlying Cambrian rocks. The Grenville-Central Province contact is present in the area and exhibits faulting, mineralization, and possibly plutonism. The Cambrian and Ordovician stratigraphy in the area is relatively simple, with clastics at the base, carbonates in the middle, and a thick shale capping the sequence. Several major facies changes are evident within the section. Structural geology is also fairly simple. However, local discontinuities are apparent and include Precambrian doming and faulting, reactivated faulting, and Knox unconformable surfaces. Potential reservoirs in the area include the Utica Shale, Trenton Limestone, St. Peter Sandstone, Rose Run sandstone, Knox dolomites, Kerbel sandstone, Eau Claire Sandstone, and Mount Simon Sandstone. Favorable source rock geochemistry and the abundance of hydrocarbon shows suggest favorable source rocks to be present. Many different types of traps have been observed.

Sitler, G.

1987-09-01

364

Geology and Metal Contents of the Ruttan volcanogenic massive sulfide deposit, northern Manitoba, Canada  

NASA Astrophysics Data System (ADS)

The Paleoproterozoic Ruttan Cu-Zn volcanogenic massive-sulfide (VMS) deposit is a large, relatively low grade, bimodal-siliciclastic type deposit in the Rusty Lake volcanic belt of northern Manitoba. The deposit contained over 82.8 million tonnes of massive sulfide, of which 55.7 million tonnes were mined from 1973 to 2002. The deposit consists of a series of moderately to steeply dipping, south-facing lenses that extend along strike at the surface for 1.1 km and to a depth of 1.0 km. These lenses occur within a steeply dipping, bimodal volcanic, volcaniclastic and siliciclastic sequence. In the immediate mine area, transitional calc-alkalic to high-silica (tholeiitic), felsic, and intermediate volcanic/volcaniclastic rocks of the Mine Sequence are host to, and intercalated with, the massive-sulfide lenses. Transitional tholeiitic to calc-alkalic basalt and andesite are present in the footwall sequence, approximately 500 m down-section from the ore horizon. The overlying rocks are predominantly fine-grained volcaniclastics and siliciclastics, but include polyfragmental agglomerate that contains mafic bombs and scoriaceous felsic fragments. Syn-depositional felsic and mafic dikes, sills, and apophyses are ubiquitous throughout the Mine Sequence, including the ore lenses, indicating continued, near-vent magmatism, and volcanism during ore formation. Fabrics in altered hostrocks have consistent, down-plunge stretching lineations to the SSE that suggest the deposit has been elongated by a factor of ~1.2-1.5; otherwise, the deposit is remarkably undeformed. Syn- and post-depositional faults in the mine area have relatively minor displacements up to tens of meters. Proximal (within 200 m) footwall rocks exhibit moderate to strong chloritization, characterized by the upper greenschist to lower amphibolite facies assemblages that include cordierite-almandine-andalusite-sillimanite-biotite ± staurolite ± anthophyllite ± talc, and local silicification. The proximal hanging wall rocks are characterized by sericite ± gahnite alteration, which is restricted to within approximately 75 m of the uppermost lenses. Additional gangue minerals are anhydrite and carbonate minerals (siderite, dolomite, ankerite, and calcite), as well as chlorite, sericite, biotite, talc, and quartz. Carbonate (excluding siderite), potassium feldspar, silicification and epidotization are common distal alteration zones in the footwall to the Mine Sequence several kilometers to the northeast. There are three principal groups of massive sulfide lenses; the East lenses, the West lenses, and the Western Anomaly lenses to the far west. In general, Cu is relatively enriched at the stratigraphic base and in the center of the deposit, whereas Zn is enriched upsection and at the outer margins. Some of the Zn-rich ore exhibits primary mineralogical layering. Parts of the West and Western Anomaly lenses show two layers with Cu-rich bases and Zn-rich tops. The massive sulfide is typically 10-40-m thick; one area along the margin of the main lenses is over 130-m thick and may represent deposition adjacent to a syn-depositional fault. The main sulfide phases are pyrite, pyrrhotite, chalcopyrite, sphalerite, and galena, with tetrahedrite as the most abundant trace phase. Gahnite is ubiquitous in the chlorite-rich assemblages adjacent to the ore lenses. The average base, precious and trace metal contents estimated from Cu and Zn concentrates, and from millhead grades and recoveries. Metals easily transported as chloride and bisulfide complexes in hydrothermal fluids including: Pb, Ag, In, Cu, Cd, Au, and Zn are enriched by 1.5-2.5 orders of magnitude in comparison to the bulk continental crust. Other elements such as Sn, Mo, and As are at near-crustal concentrations, whereas Mn, Ga, and Co are significantly depleted in comparison to the crust. Calculated metal concentrations in the average hydrothermal fluid based on the average metal contents are comparable to, or higher than those measured at sediment covered ridge hydrothermal systems, which precipitate much of their me

Barrie, C. Tucker.; Taylor, Craig; Ames, Doreen E.

2005-03-01

365

Maine Geological Survey: Online Educational Materials  

NSDL National Science Digital Library

The Maine Geological Survey (MGS) has crafted a fine set of materials for those interested in learning more about the state's natural history via virtual tours, lesson plans, and maps. First up is the Virtual Tour of Maine Geology, which includes photographs of bedrock geology, geologic hazards, mineral collecting, and surficial geology. The Lesson Plans area contains 51 lessons, including "Igneous Rock Identification" and "Composition of Topsoil." A number of MGS maps are available online in the Maps and Publications area. The site includes a Bibliography of Maine Geology, which contains over 12,000 references. Additionally, the site contains a link to the MGS publications page, which has official state of Maine wall maps available for purchase.

2013-05-30

366

Maine Geological Survey: Online Educational Materials  

NSDL National Science Digital Library

The Maine Geological Survey (MGS) has crafted a fine set of materials for those interested in learning more about the state's natural history via virtual tours, lesson plans, and maps. First up is the Virtual Tour of Maine Geology, which includes photographs of bedrock geology, geologic hazards, mineral collecting, and surficial geology. The Lesson Plans area contains 51 lessons, including "Igneous Rock Identification" and "Composition of Topsoil." A number of MGS maps are available online in the Maps and Publications area. The site includes a Bibliography of Maine Geology, which contains over 12,000 references. Additionally, the site contains a link to the MGS publications page, which has official state of Maine wall maps available for purchase.

2009-12-08

367

National Park Service: Tour of Park Geology  

NSDL National Science Digital Library

The tour of Park geologic resources includes pages specific to individual National Parks, Monuments, Recreation Areas, Preserves, Seacoasts, Reserves, and Recreation Areas. These pages are indexed by park name, state, or by one of the following topics: basin and range, caves, Colorado Plateau, fossils, glaciers, hot springs, human use, mountain building, oldest rocks, plate tectonics, river systems, sand dunes, shoreline geology, or volcanoes. Organization of each of the pages typically follows a NPS template with categories for park geology, maps, photographs, geologic research, related links, visitor information, multimedia, and "teacher features" (educational resources and links for teaching geology with National Park examples.) Common subjects that are addressed at various park sites include: minerals, rocks, fossils, cave and karst systems, coastlines, glaciers, volcanoes, faults, landforms, landslides, structures, fluvial systems, sediments, soils, stratigraphic relations, processes that form or act on geologic features and their chemical compositions, and the history of the planet and its life forms.

368

The National Park Service: Park Geology  

NSDL National Science Digital Library

A National Park Service (NPS) site primarily composed of three main sections corresponding to the following program areas within the Geologic Resources Division (GRD): Disturbed Lands Restoration and Abandoned Mineral Lands (AML), Mineral Management Programs, and Geology and Soils Programs. Of these, the first two consist principally of textual resources pertaining to Park System procedures, policies, and regulations - as well as reports on example restoration projects with a focus on stream corridor restoration, bioengineering, riparian management, and revegetation. Perhaps of most interest to educators will be the third main program area, the Geology and Soils Programs section. Here are included textual resources pertaining to NPS-GRD programs on cave and karst formations, coastal and shoreline geology, paleontology, soils (e.g., soil biology and soil surveying), geological indicators (geoindicators), and stratigraphy. Lastly, a searchable photographic collection and geologic glossary are available.

369

Observations and Measurements in Geology  

NSDL National Science Digital Library

This activity allows students to see several key geologic concepts that they will learn in greater detail later in the semester. They compare densities of two different blocks, which serve as proxies for the differences between oceanic and continental crust, and this provides an example of isostasy. They determine sedimentation rates and deduce what type of changes in environment can affect these rates. They determine the relative ages of two different Martian surfaces. Students also get to see hand samples of rock and mineral specimens, and compare hardness and relative sorting. These topics allow students exposure to several different concepts that they will develop a greater appreciation of throughout their courses.

Cochiara, Stacey

370

Connecting Soils and Glacial Geology  

NSDL National Science Digital Library

The goal of this activity is to provide students an opportunity to connect soil science to surficial geology by using a Soil Surveys. By the end of the activity, students should be able to use a Soil Survey to identify and interpret landforms and surficial features. This activity can be adapted to variety of process (ex. eolian deposits, glacial deposits, bedrock weathering, etc.). County-level soil surveys are available in both paper and online formats for the majority of the United States. Designed for a geomorphology course Has minimal/no quantitative component

Holly Dolliver

371

A geologic investigation of Longhorn Cavern  

E-print Network

Major Subject: Geology A GEOLOGIC INVESTIGATION OF LONGHORN CAVERN A Thesis by VICTORIA LYNN WALTERS Approved as to style and content by: Christ pher C. Mathewson (Chair of Committee) Wy M Ah (Member) J. R. Giardino (Member) John H. Spang... (Head of Department) December 1992 ABSTRACT A Geologic Investigation of Longhorn Cavern. (December 1992) Victoria Lynn Walters, B. S. , Stephen F. Austin State University Chair of Advisory Committee: Dr. Christopher C. Mathewson Longhorn Cavern...

Walters, Victoria Lynn

1992-01-01

372

County digital geologic mapping. Final report  

SciTech Connect

The purpose of this project is to create quality-county wide digital 1:250,000-scale geologic maps from existing published 1:250,000-scale Geologic and Mineral Resource Bulletins published by the Nevada Bureau of Mines and Geology (NBMG). An additional data set, based on current NBMG research, Major and Significant Quaternary and Suspected Quaternary Faults of Nevada, at 1:250,000 scale has also been included.

Hess, R.H.; Johnson, G.L.; dePolo, C.M.

1995-12-31

373

Safer Science: Geology--Rock Solid Safety  

NSDL National Science Digital Library

Although perceived as having a lower level of safety issues compared to chemistry or biology laboratories, Earth-space science and geology classes have their share of challenges. In fact, a number of safety concerns exist, which need to be addressed for a safe and educational experience in the geology laboratory. The following "starter" list addresses safety issues to consider with regard to common geology laboratory activities and fieldwork, as well as how to deal with other issues.

Ken Roy

2008-03-01

374

Towards understanding how surface life can affect interior geological processes: a non-equilibrium thermodynamics approach  

NASA Astrophysics Data System (ADS)

Life has significantly altered the Earth's atmosphere, oceans and crust. To what extent has it also affected interior geological processes? To address this question, three models of geological processes are formulated: mantle convection, continental crust uplift and erosion and oceanic crust recycling. These processes are characterised as non-equilibrium thermodynamic systems. Their states of disequilibrium are maintained by the power generated from the dissipation of energy from the interior of the Earth. Altering the thickness of continental crust via weathering and erosion affects the upper mantle temperature which leads to changes in rates of oceanic crust recycling and consequently rates of outgassing of carbon dioxide into the atmosphere. Estimates for the power generated by various elements in the Earth system are shown. This includes, inter alia, surface life generation of 264 TW of power, much greater than those of geological processes such as mantle convection at 12 TW. This high power results from life's ability to harvest energy directly from the sun. Life need only utilise a small fraction of the generated free chemical energy for geochemical transformations at the surface, such as affecting rates of weathering and erosion of continental rocks, in order to affect interior, geological processes. Consequently when assessing the effects of life on Earth, and potentially any planet with a significant biosphere, dynamical models may be required that better capture the coupled nature of biologically-mediated surface and interior processes.

Dyke, J. G.; Gans, F.; Kleidon, A.

2011-06-01

375

Geology Fieldnotes: Fossil Butte National Monument, Wyoming  

NSDL National Science Digital Library

Fossil Butte National Monument preserves a 50-million year old bed of Eocene limestone that contains one of the richest fossil deposits in the world. Site features include park geology information, photographs of fossils, related links, visitor information, multimedia resources, and resources for teaching geology with National Park examples. The park geology section discusses the Monument's geologic history and fossil beds, focusing on the conditions that created the fossil-rich region and on the history of fossil collection in the area. A map of the Monument is also included.

376

Geology Fieldnotes: Dinosaur National Monument, Colorado / Utah  

NSDL National Science Digital Library

Dinosaur National Monument preserves a fossil bone deposit containing the bones of hundreds of dinosaurs, which was once enclosed in the sands of an ancient river. Features of the site include park geology information, maps, photographs, related links, visitor information, multimedia resources, and resources for teaching geology with National Park examples. The geology section discusses the park's geologic history and fossil beds. A park map of the Monument is included, and the photo album section contains drawings of some of the dinosaur species found at the Monument's Dinosaur Quarry.

377

Geology of Lake Mead National Recreation Area  

NSDL National Science Digital Library

This website of the United States Geological Survey (USGS) and National Park Service (NPS) highlights the geologic history of Lake Mead National Recreation Area in Nevada and Arizona. From the Precambrian (1.8 billion years ago) until the present, the Lake Mead region has been shaped by collisions, uplift, erosion, volcanic activity, submergence, extension, and sedimentation. This site covers these major events and when they occurred in the Lake Mead area. There are links to information about geologic maps, geologic time, rocks and minerals, plate tectonics, and other Lake Mead information sources.

378

Geology Fieldnotes: Badlands National Park, South Dakota  

NSDL National Science Digital Library

Badlands National Park, located in southwestern South Dakota, consists of 244,000 acres of sharply eroded buttes, pinnacles and spires blended with the largest, protected mixed grass prairie in the United States. Features include information on park geology, maps, photographs, visitor information, links to related publications, and lesson plans for teaching geology with National Park examples. The park geology section discusses the Park's geologic history during the Eocene and Oligocene epochs and the rich fossil deposits found there. Maps of the park and the surrounding area are included.

379

Europa: Geological activity and surface - subsurface exchange  

NASA Astrophysics Data System (ADS)

Jupiter's moon Europa has a geologically young surface, allowing the possibility of current, ongoing geological activity. We are searching the Galileo database for overlapping images taken during the 5-year mission, and are comparing images using an iterative coregistration technique to look for changes due to geological activity. We will also discuss methods by which such activity could occur on Europa. We are particularly interested in the ability of geological processes to bring surface material down into the subsurface, and to bring subsurface material up to the surface. We are continuing a survey of such processes, including endogenic tectonic and cryovolcanic activity, and exogenic processes such as gardening and impact cratering.

Phillips, C. B.; Cowell, W.

2005-12-01

380

78 FR 57877 - National Cooperative Geologic Mapping Program (NCGMP) and National Geological and Geophysical...  

Federal Register 2010, 2011, 2012, 2013, 2014

...m. Mountain Standard Time. The Advisory Committee...and implementation of the geologic mapping and data preservation...m. Mountain Standard Time. FOR FURTHER INFORMATION...the National Cooperative Geologic Mapping Program and...

2013-09-20

381

77 FR 38318 - National Cooperative Geologic Mapping Program (NCGMP) and National Geological and Geophysical...  

Federal Register 2010, 2011, 2012, 2013, 2014

...m. Eastern Standard Time. The Advisory Committee...and implementation of the geologic mapping and data preservation...m. Eastern Standard Time. FOR FURTHER INFORMATION...the National Cooperative Geologic Mapping Program and...

2012-06-27

382

Pattern Alteration: Protruding Hip Bone  

E-print Network

People with very thin figures typically have to alter their clothing for protruding hip bones. This is because diagonal wrinkles radiate from the hip bones. This well-illustrated publication shows how to correct this problem in pants and skirts....

2006-08-04

383

Elements of Australian petroleum geology  

SciTech Connect

The petroleum geology of Australia reflects the existence of a large cratonic block broken away from India and Antarctica in the early Mesozoic and early Tertiary that has resulted in a rifted passive-margin character on the northwestern, western, and southern boundaries of the continent. Pre-breakup paleozoic sediments are widely distributed but commonly not deeply buried nor particularly thick, and hence contribute minimally to petroleum resource occurrence. Like their Asian neighbors, much of Australian petroleum geology is nonmarine and associated with marginal rift basins. The small Gippsland basin on the southeastern coast, which is responsible for more than 90% of oil and 28% of the gas discovered in Australia, derives its petroleum from nonmarine Eocene to Cretaceous graben-fill sediments, sealed and buried by Oligocene marine shales. The most active play in Australia is in the Eromanga depression of the Great Artesian basin, where nonmarine oil is trapped stratigraphically in small fields in Jurassic and Cretaceous sandstones. These Mesozoic sediments are sag-fill deposits above the Permian-Triassic Cooper basin, and are responsible for some 12% of the gas reserves in Australia. Offshore of the western coast, graben basins filled with late Paleozoic to Mesozoic sediments are prolific and gas-prone - 55% of reserves - owing to coaly source rocks. North Sea-type, Upper Jurassic grabens off the northwestern coast of Australia contain Kimmeridgian hot shales, but developmental drilling, following the initial Jabiru discovery, has yet to demonstrate large reserves.

Masters, C.D.; Scott, E.W.

1986-05-01

384

Geological considerations in hazardouswaste disposal  

USGS Publications Warehouse

Present regulations assume that long-term isolation of hazardous wastes - including toxic chemical, biological, radioactive, flammable and explosive wastes - may be effected by disposal in landfills that have liners of very low hydraulic conductivity. In reality, total isolation of wastes in humid areas is not possible; some migration of leachate from wastes buried in the gound will always occur. Regulations should provide performance standards applicable on a site-by-site basis rather than rigid criteria for site selection and design. The performance standards should take into account several factors: (1) the categories, segregation, degradation and toxicity of the wastes; (2) the site hydrogeology, which governs the direction and rate of contaminant transport; (3) the attenuation of contaminants by geochemical interactions with geologic materials; and (4) the release rate of unattenuated pollutants to surface or groundwater. An adequate monitoring system is essential. The system should both test the extent to which the operation of the site meets performance standards and provide sufficient warning of pollution problems to allow implementation of remedial measures. In recent years there has been a trend away from numerous, small disposal sites toward fewer and larger sites. The size of a disposal site should be based on the attenuation capacity of the geologic material, which has a finite, though generally not well-defined, limit. For slowly degradable wastes, engineered sites with leachate-collection systems appear to be only a temporary solution since the leachate collected will also require final disposal. ?? 1981.

Cartwright, K.; Gilkeson, R.H.; Johnson, T.M.

1981-01-01

385

Computer stereograms of subsurface geology  

SciTech Connect

Three-dimensional stereoscopic illustrations formerly have been a standard part of the subsurface geologist's toolkit. Now the immense complexity of stereograms can be resolved by inexpensive software on a personal computer. The construction technique is a simple combination of known technology. The subsurface geologist can gain an entirely new viewpoint. These new illustrations yield new patterns, new relationships, and prospective anomalies. Stereograms are particularly effective for displaying and interpreting complex geology in a simple way. Experienced geologists sometimes can fail to appreciate the vertical relationships involved in contour maps. Stereograms provide a more natural view of the data. They are useful also for presenting subsurface geology to persons unfamiliar with standard contouring methods and for clarifying vertical relationships to more experienced viewers. Contour maps and block diagrams were constructed with readily available, inexpensive software using kriging algorithms. Stereo pairs were created by rotating the blocks 4 degrees within the computer program. The pairs were positioned 2.5 in. apart to match an average viewer's interpupillary distance. The three-dimensional blocks may be viewed with a stereoscope or with naked eyes focused upon a distant point.

Todd, H.W.

1988-01-01

386

Teaching Resources in Structural Geology  

NSDL National Science Digital Library

To some, the terms folds, faults, and shear zones might suggest a type of elaborate and cutting-edge style of origami. Those in the know will think immediately of the field of structural geology, and this site is a fine resource for information within that area of geology. Rob Butler, Martin Casey, Geoff Lloyd, and Andrew McCaig, all of whom work in the School of Earth Sciences at the University of Leeds, created these teaching resources. Visitors can start their journey through the site by clicking on the "Basic Principles" section, which contains a nice overview of the patterns of rock organization and how geologists understand the history of rock patterns. The other sections of the site provide basic overviews of shear zones, fault patterns, minor structures, and strain. The site is rounded out by a few virtual field trips, which will be quite helpful for those who can't make it to the Himalayas or the fabled Western Gneiss region of Norway.

Butler, Rob; Casey, Martin; Lloyd, Geoff; Mccaig, Andrew

387

Long-term modeling of alteration-transport coupling: Application to a fractured Roman glass  

NASA Astrophysics Data System (ADS)

To improve confidence in glass alteration models, as used in nuclear and natural applications, their long-term predictive capacity has to be validated. For this purpose, we develop a new model that couples geochemical reactions with transport and use a fractured archaeological glass block that has been altered for 1800 years under well-constrained conditions in order to test the capacity of the model. The chemical model considers three steps in the alteration process: (1) formation of a hydrated glass by interdiffusion, whose kinetics are controlled by a pH and temperature dependent diffusion coefficient; (2) the dissolution of the hydrated glass, whose kinetics are based on an affinity law; (3) the precipitation of secondary phases if thermodynamic saturation is reached. All kinetic parameters were determined from experiments. The model was initially tested on alteration experiments in different solutions (pure water, Tris, seawater). It was then coupled with diffusive transport in solution to simulate alteration in cracks within the glass. Results of the simulations run over 1800 years are in good agreement with archaeological glass block observations concerning the nature of alteration products (hydrated glass, smectites, and carbonates) and crack alteration thicknesses. External cracks in direct contact with renewed seawater were altered at the forward dissolution rate and are filled with smectites (400-500 ?m). Internal cracks are less altered (by 1 or 2 orders of magnitude) because of the strong coupling between alteration chemistry and transport. The initial crack aperture, the distance to the surface, and sealing by secondary phases account for these low alteration thicknesses. The agreement between simulations and observations thus validates the predictive capacity of this coupled geochemical model and increases more generally the robustness and confidence in glass alteration models to predict long-term behavior of nuclear waste in geological disposal or natural glass in the environment.

Verney-Carron, Aurélie; Gin, Stéphane; Frugier, Pierre; Libourel, Guy

2010-04-01

388

The use of high resolution ground and airborne magnetic surveys to evaluate the geometry of hydrothermal alteration zones over volcanic provinces (Invited)  

NASA Astrophysics Data System (ADS)

Geophysical methods can provide critical constraints on the distribution and volume of hydrothermal alteration, important parameters in understanding the evolution of geothermal systems. Because hydrothermal alteration modifies the magnetic properties of the volcanic substratum, magnetic surveys can be used to provide constraints on the distribution of hydrothermal alteration at depth. Using Yellowstone caldera as an example, we show that both ground and airborne magnetic surveys can be used to map and assess the volume of hydrothermal alteration. Ground magnetic surveys over unaltered volcanic terranes display high-amplitude, short-wavelength anomalies, in contrast to smooth, subdued magnetic anomalies over volcanic substrata demagnetized by hydrothermal alteration. We use this contrast to map areas of hydrothermal alteration in detail. Inverse methods applied to high-resolution airborne and ground magnetic data can be used to create three-dimensional models of the distribution of magnetization and thus illuminate the geometry of hydrothermal alteration. Because of the non-uniqueness of potential fields, the construction of inverse models requires simplifying assumptions on the distribution of magnetization, knowledge of induced and remanent magnetization of fresh and altered geological units, and detailed geological and geophysical data. Within the three hydrothermal sites that we investigated in Yellowstone National Park, subdued short-wavelength signal indicates pervasive demagnetization (alteration) of the shallow substratum that extends over larger areas than initially mapped by geology. These data also reveal that the largest degree of demagnetization (alteration) and maximum thicknesses of demagnetized (altered) substratum, reaching a few hundred meters, are associated with hydrothermal vents and with superficial hydrothermal alteration. Our three dimensional models of magnetization provide estimates of the volume of buried hydrothermal alteration ranging from 10 to 20 km3 buried within each of our 10 x 10 km2 study areas.

Bouligand, C.; Glen, J. M.

2013-12-01

389

Paleontology and Geology of Indiana Department of Geological Sciences | P. David Polly 1  

E-print Network

Geol G308 Paleontology and Geology of Indiana Department of Geological Sciences | P. David Polly 1 hosts information about paleontology and geology in Indiana, copies of lecture slides and handouts for this course, but for anyone who is interested in Indiana's "deep history". Description G308 Paleontology

Polly, David

390

26 AUGUST 2009, GSA TODAY Murray Hitzman, Dept. of Geology and Geological  

E-print Network

Street, Tucson, Arizona 85721, USA, barton@geo.arizona.edu; and Maeve Boland, Dept. of Geology26 AUGUST 2009, GSA TODAY Murray Hitzman, Dept. of Geology and Geological Engineering, Colorado@geo.oregonstate. edu; Mark Barton, Dept. of Geosciences, University of Arizona, Gould-Simpson Building #77, 1040 E. 4th

Barton, Mark D.

391

Petroleum Geology Conference series doi: 10.1144/0070921  

E-print Network

Petroleum Geology Conference series doi: 10.1144/0070921 2010; v. 7; p. 921-936Petroleum Geology Collection to subscribe to Geological Society, London, Petroleum Geologyhereclick Notes on January 5, 2011Downloaded by by the Geological Society, London © Petroleum Geology Conferences Ltd. Published #12;An

Demouchy, Sylvie

392

14 CFR 26.45 - Holders of type certificates-Alterations and repairs to alterations.  

Code of Federal Regulations, 2010 CFR

...critical alteration structure. For existing and future alteration data developed by the holder...existing alteration data and identify all...critical baseline structure identified under...Review the repair data, and identify each...critical alteration structure identified...

2010-01-01

393

Natural geological responses to anthropogenic alterations of the naples bay estuarine system  

E-print Network

sediment distributions in northern Naples Bay from a coarser to a finer grained substrate. This shift has occurred to a lesser degree in southern Naples Bay, and Dollar Bay has not made this transition, due to the relative lack of anthropogenic...

Fielder, Bryan Robert

2009-05-15

394

Geological and geothermal investigations for HCMM-derived data. [hydrothermally altered areas in Yerington, Nevada  

NASA Technical Reports Server (NTRS)

An attempt was made to match HCMM- and U2HCMR-derived temperature data over two test sites of very local size to similar data collected in the field at nearly the same times. Results indicate that HCMM investigations using resolutions cells of 500 m or so are best conducted with areally-extensive sites, rather than point observations. The excellent quality day-VIS imagery is particularly useful for lineament studies, as is the DELTA-T imagery. Attempts to register the ground observed temperatures (even for 0.5 sq mile targets) were unsuccessful due to excessive pixel-to-pixel noise on the HCMM data. Several computer models were explored and related to thermal parameter value changes with observed data. Unless quite complex models, with many parameters which can be observed (perhaps not even measured (perhaps not even measured) only under remote sensing conditions (e.g., roughness, wind shear, etc) are used, the model outputs do not match the observed data. Empirical relationship may be most readily studied.

Lyon, R. J. P.; Prelat, A. E.; Kirk, R. (principal investigators)

1981-01-01

395

Contribution of LANDSAT-4 thematic mapper data to geologic exploration  

NASA Technical Reports Server (NTRS)

The increased number of carefully selected narrow spectral bands and the increased spatial resolution of thematic mapper data over previously available satellite data contribute greatly to geologic exploration, both by providing spectral information that permits lithologic differentiation and recognition of alteration and spatial information that reveals structure. As vegetation and soil cover increase, the value of spectral components of TM data decreases relative to the value of the spatial component of the data. However, even in vegetated areas, the greater spectral breadth and discrimination of TM data permits improved recognition and mapping of spatial elements of the terrain. As our understanding of the spectral manifestations of the responses of soils and vegetation to unusual chemical environments increases, the value of spectral components of TM data to exploration will greatly improve in covered areas.

Everett, J. R.; Dykstra, J. D.; Sheffield, C. A.

1983-01-01

396

Proposed geologic model based on geophysical well logs  

SciTech Connect

An investigation of the subsurface based on a qualitative interpretation of well logs was carried out at Cerro Prieto to obtain information on the distribution of the different lithofacies that make up a deltaic depositional system. The sedimentological interpretation derived from the resistivity and spontaneous potential are shown in several cross-sections of the field. In addition to the sedimentological interpretation, a map of the structural geology of the region based on well logs and available geophysical information was prepared, including the results of gravity and seismic refraction surveys. The depth to the zone of hydrothermal alteration described by Elders (1980) was found by means of temperature, electrical, and radioactive logs. Two maps showing the configuration of the top of this anomaly show a clear correlation with the gravity anomalies found in the area.

Diaz C, S.; Puente C, I.; de la Pena L, A.

1981-01-01

397

U.S. Geological Survey Open-File Report 02328 Geological Survey of Canada Open File 4350  

E-print Network

U.S. Geological Survey Open-File Report 02­328 Geological Survey of Canada Open File 4350 August simultaneously as U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 02­328 and GEOLOGICAL SURVEY OF CANADA OPEN FILE 4350 Middlefield Road, Menlo Park, California, 94025, USA 2 Pacific Geoscience Centre, Geological Survey of Canada

Goldfinger, Chris

398

Retention of neptunium in uranyl alteration phases formed during spent fuel corrosion  

SciTech Connect

Uranyl oxide hydrate phases are known to form during contact of oxide spent nuclear fuel with water under oxidizing conditions; however, less is known about the fate of fission and neutron capture products during this alteration. We describe, for the first time, evidence that neptunium can become incorporated into the uranyl secondary phase, dehydrated schoepite (UO{sub 3}.8H{sub 2}O). Based on the long term durability of natural schoepite, the retention of neptunium in this alteration phase may be significant during spent fuel corrosion in an unsaturated geologic repository.

Buck, E.C.; Finch, R.J.; Finn, P.A.; Bates, J.K.

1997-09-01

399

Retention of neptunium in uranyl alteration phases formed during spent fuel corrosion  

SciTech Connect

Uranyl oxide hydrate phases are known to form during contact of oxide spent nuclear fuel with water under oxidizing conditions; however, less is known about the fate of fission and neutron capture products during this alteration. We describe, the first time, evidence that neptunium can become incorporated into the uranyl secondary phase, dehydrated schoepite (UO{sub 3}{lg_bullet}0.8H{sub 2}O). Based on the long-term durability of natural schoepite, the retention of neptunium in this alteration phase may be significant during spent fuel corrosion in an unsaturated geologic repository.

Buck, E.C.; Finch, R.J.; Finn, P.A.; Bates, J.K.

1997-10-01

400

A megastructural end to Geologic Time  

Microsoft Academic Search

Futuristic nuclear waste disposal projects may have profound implications for the development of Anthropogeomorphology; namely, institution of an Anthropic Rock Cycle within the earth. Some time prior to 12,000 A.D., by construction of a preliminary Dyson heliosphere in the Solar System, Geologic Time could be artificially terminated and the geologic record eventually erased. Here, a new mechanical means of planetary

R. B. Cathcart

1983-01-01

401

30 CFR 780.22 - Geologic information.  

Code of Federal Regulations, 2011 CFR

...at a minimum the following: (1) A description of the geology of the proposed permit and adjacent areas down to and including...mining. The description shall include the areal and structural geology of the permit and adjacent areas, and other parameters...

2011-07-01

402

30 CFR 780.22 - Geologic information.  

Code of Federal Regulations, 2012 CFR

...at a minimum the following: (1) A description of the geology of the proposed permit and adjacent areas down to and including...mining. The description shall include the areal and structural geology of the permit and adjacent areas, and other parameters...

2012-07-01

403

30 CFR 780.22 - Geologic information.  

Code of Federal Regulations, 2014 CFR

...at a minimum the following: (1) A description of the geology of the proposed permit and adjacent areas down to and including...mining. The description shall include the areal and structural geology of the permit and adjacent areas, and other parameters...

2014-07-01

404

30 CFR 780.22 - Geologic information.  

Code of Federal Regulations, 2013 CFR

...at a minimum the following: (1) A description of the geology of the proposed permit and adjacent areas down to and including...mining. The description shall include the areal and structural geology of the permit and adjacent areas, and other parameters...

2013-07-01

405

Reports of Planetary Geology Program, 1982  

NASA Technical Reports Server (NTRS)

Work conducted in the Planetary Geology program is summarized. The following categories are presented: outer solar system satellites; asteroids and comets; Venus; cratering processes and landform development; volcanic processes and landforms; aolian processes and landforms; fluvial processes and landform development; periglacial and permafrost processes; structure, tectonics and stratigraphy; remote sensing and regolith studies; geologic mapping, cartography and geodesy.

Holt, H. E. (compiler)

1982-01-01

406

Geologic maps of Pacific basin and rim  

SciTech Connect

A major component of the Circum-Pacific Map Project is to compile five regional geologic maps at a scale of 1:10 million and a final map of the Pacific Ocean basin at a scale of 1:17 million. The Geologic Map of the Northeast Quadrant was published in 1983, and the Geologic Map of the Southeast Quadrant in 1985. The Geologic Maps of the Northwest Quadrant, the Southwest Quadrant, and the Antarctic Region are expected to reach publication during 1986. The Geologic Map of the Pacific Basin, with energy and mineral resources, is scheduled for publication in 1989. Each geologic map is a synthesis of a large amount of information. The land areas portray rock types by patterns and ages by colors; major faults are shown if they form the boundaries for map units. The oceanic areas include bathymetric contours, 13 sea-floor sediment types, all Deep Sea Drilling Program (DSDP) sites, selected DSDP columns, and selected sites of pre-Quaternary bedrock or sediment recovery. A correlation diagram on each map shows stratigraphic columns for the five regional maps, map units, geologic ages, and a time scale. An inset map shows presently active tectonic plates. The principal information sources for each sheet are given in a reference list, and each map is accompanied by explanatory notes. This map series represents the first integrated set of geologic maps of the entire Pacific Ocean basin and rim, including the Antarctic continent- altogether more than half the surface area of planet Earth.

Craddock, C.

1986-07-01

407

Geologic History Field Investigation - Minnehaha Falls  

NSDL National Science Digital Library

This activity is an inquiry-based field investigation of the geologic history of the Minnehaha Falls and St. Anthony Falls areas of Minneapolis. Students will be introduced to rocks and the stories rocks tell in a genuine geologic context, rather than as samples in the classroom.

Kevin Swanson and Justin Larson, Chippewa Middle School, North Oaks, MN

408

US Geological Survey World Energy Project  

NSDL National Science Digital Library

The World Energy Project's Website holds a wide collection of data including province assessment reports and maps showing geology, oil and gas fields, and geologic provinces (Africa, Arabian Peninsula, South Asia, South America, Former Soviet Union, Asia Pacific Region, and Iran). Finally, a report ranks the world's oil and gas provinces by known petroleum volumes.

409

Advances in planetary geology, volume 2  

NASA Technical Reports Server (NTRS)

This publication is a continuation of volume 1; it is a compilation of reports focusing on research into the origin and evolution of the solar system with emphasis on planetary geology. Specific reports include a multispectral and geomorphic investigation of the surface of Europa and a geologic interpretation of remote sensing data for the Martian volcano Ascreaus Mons.

1986-01-01

410

Abstracts for the Planetary Geology Field Conference  

NASA Technical Reports Server (NTRS)

The conference was to foster a better understanding of the volcanic history of the planets through the presentation of papers and through field trips to areas on the basalt plains of Idaho that appear to be analogous to some planetary surfaces. Papers include discussions of the volcanic geology of the Snake River Plain, general volcanic geology, and aspects of volcanism on the terrestrial planets.

Greeley, R. (editor); Black, D.

1977-01-01

411

Geology Fieldnotes: Rocky Mountain National Park, Colorado  

NSDL National Science Digital Library

In addition to offering visitor information, photographs, and links, this site traces the geologic history of this park to its beginnings as sedimentary rocks 1-2 billion years ago (Precambrian). It covers episodes of mountain building and erosion, the presence of dinosaurs and volcanoes, and glaciation, ending with the park's present geological state.

412

Geology of the Fargo-Moorehead Region  

NSDL National Science Digital Library

This is a website created by University of North Dakota - Fargo faculty member Dr. Donald Schwert detailing the urban geology of the region surrounding Fargo, ND and Moorhead, MN. There is a good deal of information about the soils in the area, the Red River which flows North through the area, and the geologic history of why things are the way they are.

Donald P. Schwert

413

Nonparametric Methods Instruction in Quantitative Geology.  

ERIC Educational Resources Information Center

Presented is an approach to introducing upper division, undergraduate geology students to nonparametric statistics and their application to geologic data. Discussed are the use of the Mann-Whitney U and the Kolmogorov-Smirnov tests and a class assignment which illustrates their use. (CW)

Kemmerly, Phillip Randall

1990-01-01

414

Geological well log analysis. Third ed  

Microsoft Academic Search

Until recently, well logs have mainly been used for correlation, structural mapping, and quantitive evaluation of hydrocarbon bearing formations. This third edition of Geologic Well Log Analysis, however, describes how well logs can be used for geological studies and mineral exploration. This is done by analyzing well logs for numerous parameters and indices of significant mineral accumulation, primarily in sediments.

Pirson

1983-01-01

415

PHYSICAL GEOLOGY LABORATORY MANUAL Tenth Edition  

E-print Network

of Contents Lab Laboratory Topic Page 1 Dimensions and Structure of Planet Earth 1 2 Physical Properties Exercises 115 10 Earthquake Location and Isoseismal Maps 119 A Future Earthquake in New York City 139 for geology students at Hofstra include information and study materials relating to this and other geology

Merguerian, Charles

416

EARTH, LIFE, AND TIME GEOLOGY 102  

E-print Network

upon their death results in: (a) the movement of nutrients from the biological to the geologic (rock diverse organisms #12;(10) The half-life if a parent-daughter isotope pair is: (a) constant over geologic time (b) the time it takes for 1/2 of the parent isotope to accumulate (c) the time it takes for 1

Kah, Linda

417

Significant achievements in the Planetary Geology Program  

Microsoft Academic Search

Developments reported at a meeting of principal investigators for NASA's planetology geology program are summarized. Topics covered include: constraints on solar system formation; asteriods, comets, and satellites; constraints on planetary interiors; volatiles and regoliths; instrument development techniques; planetary cartography; geological and geochemical constraints on planetary evolution; fluvial processes and channel formation; volcanic processes; Eolian processes; radar studies of planetary surfaces;

J. W. Head

1978-01-01

418

Geologic Mapping of the Moon - Copernicus Crater  

NSDL National Science Digital Library

This is a lesson about the Moon's Copernicus Crater. Learners will use observation to make their own geologic map of the Crater. They then identify crater features in a photogeologic image and use those observations to color their map with the appropriate geologic units.

419

Yellowstone Geologic System Database (GeoGIS)  

NSDL National Science Digital Library

This website provides access to a broad collection of geographical, geological, and geophysical data for the Yellowstone/Snake River Plain volcanic system. Data types include physical geography, geology, geophysics, geodesy, regional models, and hazards. Information may be downloaded from lists of data, and links are provided to the original sources.

Group, University O.

420

Structural Geology Mapping/GIS Software  

NSDL National Science Digital Library

This site contains Stereographic Projection and Rose Diagram plotting packages (GEOrient); a structural and drillhole calculator (GeoCalculator); strain, and shear zone calculators; geological field database information; and Geographic Information Systems (Mapinfo) software for plotting structural symbols on maps (GeoMapSymbol; previously GeoSymbol]. There are also several animations for teaching structural geology.

Holcombe, Rod

2008-01-14

421

Geologic research at The Geysers  

SciTech Connect

Geologic research at The Geysers vapor-dominated geothermal field during the past year has yielded new information on the nature of steam-reservoir porosity and permeability; the origin of the caprock; mechanisms of lateral sealing; the evolution of The Geysers hydrothermal system; and specific reservoir controls in and immediately above {open_quotes}the felsite{close_quotes}, an hypabyssal, batholith-sized pluton largely responsible for The Geysers` existence. Our research has shown that (1) fluid conduits above the felsite may be dominantly vuggy, high-angle hydrothermal veins; (2) latest-stage hydrothermal calcite in such veins may seal them at the margins of the steam reservoir; mixed-layer clays are probably the corresponding seals in the caprock; (3) steam entries in the felsite are concentrated along the top of the youngest intrusive phase in the pluton - a 1 m.y.-old granodiorite; (4) steam entries in the felsite show a negative correlation with massive borosilicate enrichments.

Hulen, J.B.; Moore, J.N.; Nielson, D.L. [Univ. of Utah, Salt Lake City, UT (United States)

1996-04-10

422

Geologic mapping using LANDSAT data  

NASA Technical Reports Server (NTRS)

The feasibility of automated classification for lithologic mapping with LANDSAT digital data was evaluated using three classification algorithms. The two supervised algorithms analyzed, a linear discriminant analysis algorithm and a hybrid algorithm which incorporated the Parallelepiped algorithm and the Bayesian maximum likelihood function, were comparable in terms of accuracy; however, classification was only 50 per cent accurate. The linear discriminant analysis algorithm was three times as efficient as the hybrid approach. The unsupervised classification technique, which incorporated the CLUS algorithm, delineated the major lithologic boundaries and, in general, correctly classified the most prominent geologic units. The unsupervised algorithm was not as efficient nor as accurate as the supervised algorithms. Analysis of spectral data for the lithologic units in the 0.4 to 2.5 microns region indicated that a greater separability of the spectral signatures could be obtained using wavelength bands outside the region sensed by LANDSAT.

Siegal, B. S.; Abrams, M. J.

1976-01-01

423

Measuring Geologic Time on Mars  

NASA Technical Reports Server (NTRS)

Recent images from Mars show compelling evidence of near-surface flowing water, aeolian activity slope processes, and ice cap evolution that underscores the dynamic geologic history of the planet. Establishing an accurate chronology for Martian planetary features is critical for addressing fundamental questions about the evolution of the planet's surface and atmosphere and the differentiation of its interior. For example, how long was standing water on the surface? If life did evolve on Mars, did it occur before or after the evolution of life on Earth? These are arguably some of the most profound questions currently being asked by the planetary science community. Yet answers will not be forthcoming without an absolute chronology of Mars history, enabling the construction of a timescale comparable to Earth's. Discussion of methods for establishing such a chronology is particularly timely in light of new missions to Mars that are being planned to return in situ measurements or samples to Earth.

2000-01-01

424

American Geological Institute: Educational Resources  

NSDL National Science Digital Library

Over the past few years, the American Geological Institute (AGI) has assembled a nice mix of resources for earth science educators, including promotional videos such as "Why Earth Science?" and a terrific world image bank. The image bank can be found at the "Earth Science World Image Bank" tab, and it contains over 6,000 images. Visitors can browse the images, or they can also type in keywords. The site also includes videos which originally appeared in the online version of "Earth" magazine. These short subjects cover "Black Gold Agriculture", "Platinum from the Deep", and "State of the Nation's Ecosystems". Visitors can also read their publication "Pulse of Earth Science Education", which offers an overview of the trends in the field.

425

Geological remote sensing in Africa  

NASA Technical Reports Server (NTRS)

Programs using remote sensing to obtain geologic information in Africa are reviewed. Studies include the use of Landsat MSS data to evaluate petroleum resources in sedimentary rock terrains in Kenya and Sudan and the use of Landsat TM 30-m resolution data to search for mineral deposits in an ophiolite complex in Oman. Digitally enhanced multispectral SPOT data at a scale of 1:62,000 were used to map folds, faults, diapirs, bedding attitudes, and stratigraphic units in the Atlas Mountains in northern Algeria. In another study, SIR-A data over a vegetated and faulted area of Sierra Leone were compared with data collected by the Landsat MSS and TM systems. It was found that the lineaments on the SIR-A data were more easily detected.

Sabins, Floyd F., Jr.; Bailey, G. Bryan; Abrams, Michael J.

1987-01-01

426

Multistage hydrothermal silicification and Fe-Tl-As-Sb-Ge-REE enrichment in the Red Dog Zn-Pb-Ag district, northern Alaska: Geochemistry, origin, and exploration applications  

USGS Publications Warehouse

Geochemical analyses of major, trace, and rare earth elements (REE) in more than 200 samples of variably silicified and altered wall rocks, massive and banded sulfide, silica rock, and sulfide-rich and unmineralized barite were obtained from the Main, Aqqaluk, and Anarraaq deposits in the Red Dog Zn-Pb-Ag district of northern Alaska. Detailed lithogeochemical profiles for two drill cores at Aqqaluk display an antithetic relationship between SiO2/Al2O3 and TiO2/Zr which, together with textural information, suggest preferential silicification of carbonate-bearing sediments. Data for both drill cores also show generally high Tl, Sb, As, and Ge and uniformly positive Eu anomalies (Eu/Eu* > 1.0). Similar high Tl, Sb, As, Ge, and Eu/Eu* values are present in the footwall and shallow hanging wall of Zn-Pb-Ag sulfide intervals at Anarraaq but are not as widely dispersed. Net chemical changes for altered wall rocks in the district, on the basis of average Al-normalized data relative to unaltered black shales of the host Kuna Formation, include large enrichments (>50%) of Fe, Ba, Eu, V, S, Co, Zn, Pb, Tl, As, Sb, and Ge at both Red Dog and Anarraaq, Si at Red Dog, and Sr, U, and Se at Anarraaq. Large depletions (>50%) are evident for Ca at both Red Dog and Anarraaq, for Mg, P, and Y at Red Dog, and for Na at Anarraaq. At both Red Dog and Anarraaq, wall-rock alteration removed calcite and minor dolomite during hydrothermal decarbonation reactions and introduced Si, Eu, and Ge during silicification. Sulfidation reactions deposited Fe, S, Co, Zn, Pb, Tl, As, and Sb; barite mineralization introduced Ba, S, and Sr. Light REE and U were mobilized locally. This alteration and mineralization occurred during Mississippi an hydrothermal events that predated the Middle Jurassic-Cretaceous Brookian orogeny. Early hydrothermal silicification at Red Dog took place prior to or during massive sulfide mineralization, on the basis of the dominantly planar nature of Zn-Pb veins, which suggests filling of fractures that developed in previously lithified rock. Uniformly low Ca and Mg and uniformly negative Ce anomalies in highly siliceous Red Dog wall rocks reflect hydrothermal decarbonation reactions and pervasive silicification owing to conductive cooling of oxidized metalliferous fluids. Similar Ca and Mg depletions are evident at Anarraaq but generally lack associated silicification, possibly because temperatures of the hydrothermal fluids were too low (<180??C) or because the thermal contrast between the fluids and wall rocks was smaller owing to the greater depth of alteration and mineralization there, compared with Red Dog. Chalcophile element anomalies (Fe, Zn, Pb, Tl, As, Sb) in wall rocks at both Red Dog and Anarraq are attributed to sulfidation reactions, coeval with subsurface Zn-Pb-Ag mineralization, during the mixing of oxidized metalliferous fluids with H2S-rich fluids derived locally within the Kuna Formation. Sedimentary wall rocks in the Red Dog district are characterized by a distinctive suite of geochemical anomalies, especially for Zn, Pb, Tl, As, Sb, Ge, and Eu/Eu*. At the Aqqaluk deposit, wall rocks without visible sphalerite or galena (<300 ppm Zn + Pb) have anomalous Eu/Eu*, Tl, Sb, and As for up to ???100 m stratigraphically below Zn-rich silica rock. At Anarraaq, the Tl anomaly is most extensively developed, and enrichment relative to unaltered black shale of the Kuna Formation is present up to 62 m above the highest Zn-Pb sulfide zones. The magnitude of the enrichment and systematic behavior of Tl in the district make Tl a promising geochemical exploration guide for Red Dog-type Zn-Pb-Ag deposits elsewhere. ?? 2004 by Economic Geology.

Slack, J.F.; Kelley, K.D.; Anderson, V.M.; Clark, J.L.; Ayuso, R.A.

2004-01-01

427

Quantitative bedrock geology of Brazil  

NASA Astrophysics Data System (ADS)

We quantitatively analyze the area-age distribution of sedimentary, igneous, metamorphic, and ultramafic bedrock on the basis of data from the digital geologic map of Brazil, published as a GIS map by the Brazilian Geological Survey. Bedrock units exclusively encompassing sedimentary rocks, igneous rocks, or metamorphic rocks cover 40.4%, 31.5%, and 17.7%, respectively, of the total bedrock area. These numbers have to be considered minimum estimates of the areal abundance of sedimentary, igneous, and metamorphic bedrock because polygons defined by mixed lithologies cover ˜8.5-9.5% of the total bedrock area. These mixed units are sedimentary rocks with igneous and/or metamorphic contributions (1.4%), metamorphic rocks with sedimentary contributions (1.2%), metamorphic rocks with igneous contributions (1.5%), igneous rocks with sedimentary and/or metamorphic contributions (4.4%), and ultramafic units with sedimentary, igneous, and/or metamorphic contributions (˜1-2%). The average ages of major lithologic units, weighted according to bedrock area, are as follows: sedimentary rocks (average stratigraphic age of 248 ± 5 [1?] Myr; median stratigraphic age of 87.5 Myr), igneous rocks (1153 ± 13 [1?] Myr), metamorphic rocks (1678 ± 30 [1?] Myr), and ultramafic rocks (˜1227 ± 25 [1?] Myr). The average bedrock age of Brazil is 946 ± 7 [1?] Myr. The range in lithologic composition and age structure of the various bedrock units reflects the complex tectonic makeup of Brazil that ranges from Neogene sedimentary cover in the Amazon Basin to Precambrian cratons (Guyana and Brazilian shields) and Transamazonian greenstone belts. The average spatial resolution of the data is 232 km2 polygon-1 and is sufficient to perform area-age analyses of individual river drainage basins larger than ˜5,000 km2.

Peucker-Ehrenbrink, Bernhard; Miller, Mark W.

2007-05-01

428

Petroleum geology of western Antarctica  

SciTech Connect

Antarctica's geology is mostly obscured by thick, moving ice that covers 95% of the land and continental shelf. Reconnaissance investigations of outcrops, shallow boreholes, and geophysical surveys are limited and peripheral owing to ice coverage. However, it is possible to outline substantial elements of the regional geology. Further insight is gained by comparison to analogous sedimentary provinces, especially provinces once adjoined within the framework of the Gondwana supercontinent until middle Cretaceous. The petroleum potential of Antarctica, as in the case of the other related high-standing Gondwana continental fragments, is in Early Cretaceous rifts associated with the Gondwana breakup and with the Pacific convergence in the west Antarctica back arc. The Pacific-facing western Antarctica includes two structural provinces: (1) the Cretaceous and younger interior rift system on the east side of the Weddell and Ross Sea embayment, which contain aulacogens that form the boundary with East Antarctica and (2) the back-arc and fore-arc basins adjoining the Antarctica Peninsula and extending into Marie Byrd Land and the Bellingshausen Sea which are associated with the eastward convergence of the Pacific plate. The petroleum potential of the rifts may be assessed by analogies with related rifts of Australia, India, and South Africa; assessment of the convergent basins of western Antarctica depends upon analogy with similar basins of South America, New Zealand, and Indonesia. An estimate of the petroleum potential of western Antarctica generally is comparable with oil and gas occurrences (both in overall quantity and in field sizes) in the other Gondwana continental fragments. However, in view of the thict moving ice cover, the remote locale, and severe climate, petroleum production is largely beyond technology at this time and probably is economically unfeasible.

Kingston, J. (Geological Survey, Santa Barbara, CA (USA))

1990-05-01

429

CASP: Geological exploration and research  

SciTech Connect

The Cambridge Arctic Shelf Programme (CASP) is an independent, non-profit-making geological research organization based in the University of Cambridge. It originated in 1948 as Cambridge Spitsbergen Expeditions, and was incorporated as CASP in 1975. Initially, support came from companies with an interest in Svalbard and the Barents Shelf. Since then, CASP has greatly increased its scope, diversifying to new areas of research outside the Arctic and to new methods of data presentation. CASP now offers a unique programme of research, specialising in field- and literature-based studies of remote areas. Projects are currently being undertaken in the Arctic, Russia, China, East Greenland and Eastern Europe; all projects involve fieldwork and ail involve collaboration with research groups in other institutions. Most projects are oriented towards sedimentology, stratigraphy, tectonics, basin analysis and regional geology. CASP has a unique status: it shares elements in common with universities (undertaking long-term research programmes for eventual publication), consultancies (carrying out applied projects oriented towards hydrocarbon exploration and production) and national surveys (compiling and managing large datasets). Individual projects are funded by annual subscription from interested companies, with research material being supplied on a non-exclusive basis. Input and feedback from subscribers is welcomed, and an annual consortium meeting is organised for each project. As a non-profit-making Organization with low overheads, all additional income raised for a project is used to develop the research programme. CASP projects are supported by an outstanding library/information centre and linguistic expertise (Russian and Chinese), and these facilities are available to subscribing companies.

Macdonald, D.I.M.; Scott, R.A. [Cambridge Arctic Shelf Programme (United Kingdom)

1995-08-01

430

Geology and religion in Portugal  

PubMed Central

This paper addresses the relationship between geology and religion in Portugal by focusing on three case studies of naturalists who produced original research and lived in different historical periods, from the eighteenth to the twentieth century. Whereas in non-peripheral European countries religious themes and even controversies between science and religion were dealt with by scientists and discussed in scientific communities, in Portugal the absence of a debate between science and religion within scientific and intellectual circles is particularly striking. From the historiographic point of view, in a country such as Portugal, where Roman Catholicism is part of the religious and cultural tradition, the influence of religion in all aspects of life has been either taken for granted by those less familiar with the national context or dismissed by local intellectuals, who do not see it as relevant to science. The situation is more complex than these dichotomies, rendering the study of this question particularly appealing from the historiographic point of view, geology being by its very nature a well-suited point from which to approach the theme. We argue that there is a long tradition of independence between science and religion, agnosticism and even atheism among local elites. Especially from the eighteenth century onwards, they are usually portrayed as enlightened minds who struggled against religious and political obscurantism. Religion—or, to be more precise, the Roman Catholic Church and its institutions—was usually identified with backwardness, whereas science was seen as the path to progress; consequently men of science usually dissociated their scientific production from religious belief.

Carneiro, Ana; Simoes, Ana; Diogo, Maria Paula; Mota, Teresa Salomé

2013-01-01

431

Report on geologic exploration activities  

SciTech Connect

This report provides an overview of the geological exploration activities being carried out as part of the National Waste Terminal Storage (NWTS) Program, which has been established by the US Department of Energy (DOE) to develop the technology and provide the facilities for the safe, environmentally acceptable isolation of civilian high-level and transuranic nuclear wastes, including spent fuel elements, for which the Federal government is reponsible. The principal programmatic emphasis is on disposal in mined geologic repositories. Explorations are being conducted or planned in various parts of the country to identify potential sites for such repositories. The work is being undertaken by three separate but coordinated NWTS project elements. Under the Basalt Waste Isolation Project (BWIP), basalt formations underlying DOE's Hanford Reservation are being investigated. Granite, tuff, and shale formations at the DOE Nevada Test Site (NTS) are being similarly studied in the Nevada Nuclear Waste Storage Investigations (NNWSI). The Office of Nuclear Waste Isolation (ONWI) is investigating domed salt formations in several Gulf Coast states and bedded salt formations in Utah and Texas. Th ONWI siting studies are being expanded to include areas overlying crystalline rocks, shales, and other geohydrologic systems. The current status of these NWTS efforts, including the projected budgets for FY 1981, is summarized, and the criteria and methodology being employed in the explorations are described. The consistency of the overall effort with the recommendations presented in the Report to the President by the Interagency Review Group on Nuclear Waste Management (IRG), as well as with documents representing the national technical consensus, is discussed.

None

1980-01-01

432

North Dakota geology school receives major gift  

NASA Astrophysics Data System (ADS)

Petroleum geology and related areas of study at the University of North Dakota (UND) received a huge financial boost with the announcement on 24 September of $14 million in private and public partnership funding. The university announced the naming of the Harold Hamm School of Geology and Geological Engineering, formerly a department within the College of Engineering and Mines, in recognition of $10 million provided as a gift by oilman Harold Hamm and Continental Resources, Inc. Hamm is the chair and chief executive officer of Continental, the largest leaseholder in the Bakken Play oil formation in North Dakota and Montana, and he is also an energy policy advisor to Republican presidential candidate Mitt Romney. UND also received $4 million from the Oil and Gas Research Program of the North Dakota Industrial Commission to support geology and geological engineering education and research.

Showstack, Randy

2012-10-01

433

Planetary geology and terrestrial analogs in Asia  

NASA Astrophysics Data System (ADS)

2011 PERC Planetary Geology Field Symposium;Kitakyushu City, Japan, 5-6 November 2011 In spite of the extremely diverse geological settings that exist in Asia, relatively little attention has previously been paid to this region in terms of terrestrial analog studies for planetary application. Asia is emerging as a major center of studies in planetary geology, but no attempt had been made in the past to organize a broadly based meeting that would allow planetary geologists in Asia to meet with ones from more advanced centers, such as the United States and Europe, and that would include the participation of many geologists working primarily on terrestrial research. The Planetary Exploration Research Center (PERC) of the Chiba Institute of Technology hosted the first planetary geology field symposium in Asia to present results from recent planetary geology studies and to exchange ideas regarding terrestrial analogs (http://www.perc.it-chiba.ac.jp/meetings/pgfs2011/index.html).

Komatsu, Goro; Namiki, Noriyuki

2012-04-01

434

Geologic Heritage in the National Parks  

NSDL National Science Digital Library

What is geologic heritage, you ask? In short, it "encompasses the significant geologic features, landforms, and landscapes characteristic of our Nation." The National Park Service has a special program to document these sites and to provide the public with resources about these unique destinations. The materials here are divided into four featured programs: Fossil Resources, Geologic Heritage Conservation, Park Geology Tour, and Cave and Karst Resources. Using the Park Geology Tour, visitors can search through thematic areas such as glaciers, fossils, and plate tectonics to find highlights from a vast array of National Park units. The Cave and Karst Resources program brings together resources on some of the over 4,900 caves in the National Park system, along with detailed photo galleries, newsletters, and brochures. Finally, under Fossil Resources visitors can find information about National Fossil Day and even helpful lesson plans for teachers.

2013-03-22

435

Global Geological Map of Venus  

NASA Astrophysics Data System (ADS)

Introduction: The Magellan SAR images provide sufficient data to compile a geological map of nearly the entire surface of Venus. Such a global and selfconsistent map serves as the base to address the key questions of the geologic history of Venus. 1) What is the spectrum of units and structures that makes up the surface of Venus [1-3]? 2) What volcanic/tectonic processes do they characterize [4-7]? 3) Did these processes operated locally, regionally, or globally [8- 11]? 4) What are the relationships of relative time among the units [8]? 5) At which length-scale these relationships appear to be consistent [8-10]? 6) What is the absolute timing of formation of the units [12-14]? 7) What are the histories of volcanism, tectonics and the long-wavelength topography on Venus? 7) What model(s) of heat loss and lithospheric evolution [15-21] do these histories correspond to? The ongoing USGS program of Venus mapping has already resulted in a series of published maps at the scale 1:5M [e.g. 22-30]. These maps have a patch-like distribution, however, and are compiled by authors with different mapping philosophy. This situation not always results in perfect agreement between the neighboring areas and, thus, does not permit testing geological hypotheses that could be addressed with a self-consistent map. Here the results of global geological mapping of Venus at the scale 1:10M is presented. The map represents a contiguous area extending from 82.5oN to 82.5oS and comprises ~99% of the planet. Mapping procedure: The map was compiled on C2- MIDR sheets, the resolution of which permits identifying the basic characteristics of previously defined units. The higher resolution images were used during the mapping to clarify geologic relationships. When the map was completed, its quality was checked using published USGS maps [e.g., 22-30] and the catalogue of impact craters [31]. The results suggest that the mapping on the C2-base provided a highquality map product. Units and structures: A limited set of material units and tectonic structures describes the geological situation on the surface of Venus (Fig. 1). The globally applicable stratigraphic sequence summarizing varieties of local to regional columns consists of the following units (from older to younger), the relative ages of which are established by relationships of embayment: Tessera (t) represents elevated regions deformed by multiple sets of tectonic structures. Densely lineated plains (pdl) are dissected by numerous subparallel narrow and short lineaments. Ridged plains (pr) commonly form elongated belts of ridges. Shield plains (psh) have numerous small volcanic edifices on the surface. Regional plains were divided into the lower (pr1) and the upper (pr2) units. The lower unit has uniform and relatively low radar albedo; the upper unit is brighter and often forms flow-like occurrences. Shield clusters (sc) are morphologically similar to psh but occur as small patches that postdate regional plains. Smooth plains (ps) have uniform and low radar albedo and occur near impact craters and at distinct volcanic centers. Lobate plains (pl) form fields of lava flows that are typically undeformed by tectonic structures and are associated with major volcanic centers. Several structural assemblages complicate the surface of the material units: Tessera-forming structures (ridges and grooves), belts of ridges, belts of grooves (structural unit gb), mountain belts (structural unit mt that occurs around Lakhmi Planum), wrinkle ridges, and rift zones (structural unit rt). The higly tectonized material and structural units such as t, pdl, pr, mt, and gb predate vast plains units such as psh and rp1. Wrinkle ridges deform all units that are older than units ps and pl. Smooth and lobate plains together with rift zones and shield clusters appear to be contemporaneous and form the top of the global stratigraphic column. Crater statistics: Two factors, the atmosphere screening [32-34] and the observational bias [35], appear to affect the statistics of the smaller craters on Venus. For the larger crater

Ivanov, M. A.

2008-09-01

436

Online Courses: Mississippi State University: Geology I: Processes and Products  

NSDL National Science Digital Library

Does your curriculum include concepts in geology? Do you need to continue your education in earth science? Geology I from the Teachers in Geosciences covers the foundational material in physical geology that you need to understand to successfully teach

1900-01-01

437

36 CFR 902.59 - Geological and geophysical information.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Geological and geophysical information. 902.59...Access to Corporation Records § 902.59 Geological and geophysical information. Any geological or geophysical information and data...

2010-07-01

438

BRIGHAM YOUNG UNIVERSITY GEOLOGY STUDIES Volume 27, Part I  

E-print Network

#12;BRIGHAM YOUNG UNIVERSITY GEOLOGY STUDIES Volume 27, Part I Preble Formation, a Cambrian Outer ..........................................................................J. Roger Olsen Geology of the Sterling Quadrangle, Sanpete County, Utah ..............................................................................James Michael Taylor Publications and Maps of the Geology Department Cover: Aertalphorograph rhowing

Seamons, Kent E.

439

Leonardo da Vinci: Founder of the science of geological facies  

Microsoft Academic Search

Existing ideas on the history of geology are refined. It is shown that Leonardo da Vinci is the founder of the science of geological facies. His principal geological concepts, which passed several centuries ahead of time, are discussed.

M. G. Berger

2005-01-01

440

The National Geologic Mapping Act of 1992  

SciTech Connect

The well being of any nation is based, in large part, on its ability to locate and prudently use its mineral and water resources; to assess potential harm to its citizens from natural hazards; and to provide for safe disposal of its waste material. These tasks require a detailed knowledge of the character and distribution of geologic materials at or near the surface of the earth, and geologic maps are the principal sources of these types of information. Geologic maps provide essential information regarding the assessment of mineral, energy, and water resources; locating potential sites for the safe disposal of hazardous and nonhazardous waste; land-use planning; earthquake-hazard reduction; predicting volcanic hazards; reducing losses from landslides and other ground failures; mitigating effects of coastal and stream erosion; siting of critical facilities; and basic earth-science research. Geologic maps are the primary sources of geologic information for nearly all decision making related to the habitation of the earth's surface and the use of its resources. Available maps are in continuous use by Federal agencies, state and local governments, private industries, and the general public, but large areas of the US have remained unmapped, or mapped at scales to small to be of general use. Recognizing the increasing National need for geologic maps, the Association of American State Geologists initiated an effort in 1989 to establish a geologic mapping program for the entire US. After developing an implementation plan in concert with the US Geological Survey, the Association of American State Geologists arranged for geologic mapping bills to be introduced simultaneously in both houses of Congress in late 1991. On May 18, 1992, President Bush signed the National Geologic Mapping Act into law.

Haney, D.C. (Univ. of Kentucky, Lexington, KY (United States). Kentucky Geological Survey)

1993-03-01

441

Web2.0 digital panoramic geological field practice base  

Microsoft Academic Search

Geological field practice is a necessary part of the teaching in geology related. Digital panoramic geological field practice base is designed based on B\\/S model, using Web2.0 technology and panoramic images to archive real geological field environment. Take Xingcheng geological field practice base of Jilin University as the demonstration, established Xingcheng digital panoramic geological field practice base, the system providing

Wang Man; Xue Linfu; Deng Chunyan; Wang Yingwei; Li Wenqing

2010-01-01

442

Alteration of fractured cementitious materials  

SciTech Connect

The alteration of cement materials in a fractured repository was investigated by experimental and modelling techniques to predict the long-term evolution of a cementitious repository for the safety assessment of radioactive waste disposal. A flow-through experiment with an artificially fractured cement column sample was carried out, and the evolution of a chemical composition in discharged water and the distribution of mineral components in a solid matrix, which was dominated by the dissolution of portlandite and calcium-silicate hydrate (C-S-H), were observed. A coupling transport and chemical equilibrium calculation code, which includes a thermodynamic incongruent dissolution model of C-S-H, was developed to predict the alteration of the fractured cement materials. The advection transport of a component in a solution within a crack and the diffusion of a component in a solid matrix were modelled in the calculations. With the proposed model, the possible alteration of cement materials along a crack was described.

Sugiyama, Daisuke [Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1, Iwado Kita, Komae-shi, Tokyo 201-8511 (Japan)], E-mail: daisukes@criepi.denken.or.jp; Fujita, Tomonari; Chida, Taiji; Tsukamoto, Masaki [Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1, Iwado Kita, Komae-shi, Tokyo 201-8511 (Japan)

2007-08-15

443

Pattern Alteration: Bodice Back Width  

E-print Network

or lap as needed. Tape the pattern in place (Fig. 10). To complete either alteration: 6. Redraw the shoulder seam and cutting lines to straight lines. Redraw the lower edge to a smooth cut- ting line (Figs. 9 and 10). Kimono or dolman sleeve bodice... To alter a kimono or dolman sleeve bodice: 1. Fold in the shoulder dart, if any. Measure 3 inches (7.5 cm) from the normal neck seam along the shoulder seam line, and mark it. Release the dart (Fig. 11). 2. Draw a vertical line from the marked point...

2006-03-24

444

Boullier The fault zone geology 1 Fault zone geology: lessons from drilling through the Nojima and 1  

E-print Network

Boullier The fault zone geology 1 Fault zone geology: lessons from drilling through the Nojima and 1 Chelungpu faults 2 3 Anne-Marie Boullier 4 active faults with the aim of 11 learning about the geology of the fault

Paris-Sud XI, Université de

445

Geology and Geophysics College of Science code-BS  

E-print Network

Geology and Geophysics College of Science code-BS Code-GEOP 120 Credits "C-"or better required ******************************************************************************************************************************** (effective Fall 2013) #12;Geology and Geophysics http

Kihara, Daisuke

446

Geology Before Pluto: Pre-encounter Considerations  

NASA Technical Reports Server (NTRS)

Pluto, its large satellite Charon, and its four known satellites represent the first trans-Neptunian Kuiper Belt objects populating the outer-most solar system beyond the gas giant planets to be studied in detail from a spacecraft (New Horizons). A complete picture of the solar nebula, and solar system formation cannot be confidently formulated until representatives of this group of bodies at the edge of solar space have been examined. The Pluto system is composed of unique lunar- and intermediate-sized objects that can tell us much about how objects with volatile icy compositions evolve. Modeling of the interior suggests that geologic activity may have been to some degree, and observations of frost on the surface could imply the need for a geologic reservoir for the replenishment of these phases. However, the putative indicators of Pluto's geologic history are inconclusive and unspecific. Detailed examination of Pluto's geologic record is the only plausible means of bridging the gap between theory and observations. In this talk I will examine the potential importance of these tentative indications of geologic activity and how specific spacecraft observations have been designed and used to constrain the Pluto system's geologic history. The cameras of New Horizons will provide robust data sets that should be immanently amenable to geological analysis of the Pluto System's landscapes. In this talk, we begin with a brief discussion of the planned observations by New Horizons' cameras that will bear most directly on geological interpretability. Then I will broadly review major geological processes that could potentially operate of the surfaces of Pluto and its moons. I will first survey exogenic processes (i.e., those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration) and the work of wind. I will conclude with an assessment of prospects for endogenic activity in the form of tectonics and cryo-volcanism.

Moore, Jeffrey M.

2014-01-01

447

Mapping Vesta: A Geological Overview  

NASA Astrophysics Data System (ADS)

Observations from the Dawn (Russell et al., 2007) spacecraft enabled deriva-tion of 4Vesta's shape, facilitated mapping of the surface geology and pro-vided the first evidence for Vesta's geological evolution. The Dawn mission is equipped with a framing camera (FC), a visible and infrared mapping spectrometer (VIR) and a gamma-ray and neutron detector (GRaND). So far science data are collected during the approach to the asteroid and protoplanet Vesta, a circular polar orbit at an altitude of 2700 km providing ~ 230 m/pix camera resolution and a lower orbit, at 700 km altitude with a camera resolu-tion of ~ 65 m/pixel. Geomorphology and distribution of surface features provide evidence for impact cratering, tectonic activity, regolith and prob-able volcanic processes. Craters with dark rays, bright rays, and dark rim streaks have been observed, suggesting possible buried stratigraphy. The largest fresh craters retain a simple bowl-shaped morphology, with depth/diameter ratios roughly comparable to lunar values. The largest candi-date crater, a ~460 km depression at the south pole, has been shown to con-tain an incomplete inward facing cuspate scarp, and a large central mound surrounded by unusual complex arcuate ridge and groove patterns. Although asymmetric in general form, these characteristics do not contradict an impact origin but may also allow endogenic processes like convective downwelling or hybrid modification of an impact. Rapid rotation of Vesta during impact may explain some anomalous features (Jutzi and Asphaug, 2010). A set of large equatorial troughs may be related to the formation process of the south polar structure or due to stress caused by changes of the rotational axis. The crater size frequency and the chronology function is derived from the lunar chronology, scaled to impact frequencies modeled for Vesta according to (Bottke et al., 1994) and (O'Brien and Sykes, 2011). The northern hemi-sphere is heavily cratered by a large variety of ancient degraded and fresh sharp craters. Preliminary crater counts indicate only small differences in absolute surface model ages between the northern region and the south polar structure.

Jaumann, R.; Pieters, C. M.; Russell, C. T.; Raymond, C. A.; Yingst, R.; Williams, D. A.; Schenk, P.; Neukum, G.; Mottola, S.; Buczkowski, D.; O'Brien, D. P.; Garry, W. B.; Blewett, D. T.; Denevi, B. W.; Roatsch, T.; Preusker, F.; Nathues, A.; Sierks, H.; Sykes, M. V.; De sanctis, M.; McSween, H. Y.; Keller, H. U.; Marchi, S.

2011-12-01

448

Page 1 | B.S. in Geology | Academic Plan of Study Updated April 2014 B.S. in Geology  

E-print Network

in topics like sedimentology, structural geology and mineralogy. Extracurricular experiences are important in the subjects of geomorphology, sedimentology, and structural geology. In addition, students at UNC Charlotte

Raja, Anita

449

Altered Vision Near the Hands  

ERIC Educational Resources Information Center

The present study explored the manner in which hand position may affect visual processing. We studied three classic visual attention tasks (visual search, inhibition of return, and attentional blink) during which the participants held their hands either near the stimulus display, or far from the display. Remarkably, the hands altered visual…

Abrams, Richard A.; Davoli, Christopher C.; Du, Feng; Knapp, William H., III; Paull, Daniel

2008-01-01

450

Electrically alterable digital differential analyzer  

Microsoft Academic Search

Computer simulations are performed for scientific problems using analog computer techniques for speed and functional similarity to the actual problem. The analog computers are severely limited in accuracy. This inherent accuracy limitation on high speed simulation requirements can be overcome by the application of the Teledyne Electrically Alterable Digital Differential Analyzer (TEADDA), which is a high speed completely parallel \\

Gilbert P. Hyatt; Gene Ohlberg

1968-01-01

451

Art as Alterity in Education  

ERIC Educational Resources Information Center

In education, art has often been perceived as entertainment and decoration and is the first subject to go when there are budget cuts or test-score pressures. Drawing on Emmanuel Lévinas's idea of the primacy of radical alterity that breaks the totality of our being, enables self-transformation and ethics, and ensures community as a totality…

Zhao, Guoping

2014-01-01

452

The Geologic Story of Yosemite Valley  

NSDL National Science Digital Library

This website of the United States Geological Survey (USGS) and the National Park Service (NPS) discusses the geology of Yosemite Valley in California, beginning 100 million years ago with the formation of the granite rocks found in this park and continuing with jointing, exfoliation, and erosion through ice and water. Bedrock Geology includes details about the formation, classification, and descriptions of the plutonic bedrock. It also discusses the relationship of landforms to rock composition and structure and their role in shaping the Yosemite valley.

Huber, N.

453

Geology Fieldnotes: Bryce Canyon National Park, Utah  

NSDL National Science Digital Library

Located on the Colorado Plateau in Utah, this canyon is comprised mostly of sedimentary rocks, and continues to be eroded and shaped by the Paria River. Its geologic and human history are outlined on this site, including the formation of the canyon, from the Cretaceous period (144 million years ago) to the present, and geologic features, such as fins, columns, pinnacles, and hoodoos. Visitor information, links to other resources, maps, and a teacher feature (resources for teaching geology with National Park examples) are also available.

Foos, Annabelle

454

Geology of Death Valley National Park  

NSDL National Science Digital Library

This site of the United States Geologic Survey (USGS) and the National Park Service (NPS) highlights the geologic history of Death Valley National Park in Nevada and California. The story begins 1.8 billion years ago with the formation of rocks and continues through uplift, faulting, volcanism, early animals of the area, glaciers, and the making of deserts and dunes. A geologic timescale connects to specific events in the history of Death Valley. There are topographic maps of the area, a field trip of the park, an image gallery, and technical papers available to download.

455

The Black Mountain tectonic zone--a reactivated northeast-trending crustal shear zone in the Yukon-Tanana Upland of east-central Alaska: Chapter D in Recent U.S. Geological Survey studies in the Tintina Gold Province, Alaska, United States, and Yukon, Canada--results of a 5-year project  

USGS Publications Warehouse

The Black Mountain tectonic zone in the YukonTanana terrane of east-central Alaska is a belt of diverse northeast-trending geologic features that can been traced across Black Mountain in the southeast corner of the Big Delta 1°×3° degree quadrangle. Geologic mapping in the larger scale B1 quadrangle of the Big Delta quadrangle, in which Black Mountain is the principal physiographic feature, has revealed a continuous zone of normal and left-lateral strikeslip high-angle faults and shear zones, some of which have late Tertiary to Quaternary displacement histories. The tectonic zone includes complexly intruded wall rocks and intermingled apophyses of the contiguous mid-Cretaceous Goodpaster and Mount Harper granodioritic plutons, mafic to intermediate composite dike swarms, precious metal mineralization, early Tertiary volcanic activity and Quaternary fault scarps. These structures define a zone as much as 6 to 13 kilometers (km) wide and more than 40 km long that can be traced diagonally across the B1 quadrangle into the adjacent Eagle 1°×3° quadrangle to the east. Recurrent activity along the tectonic zone, from at least mid-Cretaceous to Quaternary, suggests the presence of a buried, fundamental tectonic feature beneath the zone that has influenced the tectonic development of this part of the Yukon-Tanana terrane. The tectonic zone, centered on Black Mountain, lies directly above a profound northeast-trending aeromagnetic anomaly between the Denali and Tintina fault systems. The anomaly separates moderate to strongly magnetic terrane on the northwest from a huge, weakly magnetic terrane on the southeast. The tectonic zone is parallel to the similarly oriented left-lateral, strike-slip Shaw Creek fault zone 85 km to the west.

O'Neill, J. Michael; Day, Warren C.; Alienikoff, John N.; Saltus, Richard W.

2007-01-01

456

Global Warming in Geologic Time  

SciTech Connect

The notion is pervasive in the climate science community and in the public at large that the climate impacts of fossil fuel CO2 release will only persist for a few centuries. This conclusion has no basis in theory or models of the atmosphere / ocean carbon cycle, which we review here. The largest fraction of the CO2 recovery will take place on time scales of centuries, as CO2 invades the ocean, but a significant fraction of the fossil fuel CO2, ranging in published models in the literature from 20-60%, remains airborne for a thousand years or longer. Ultimate recovery takes place on time scales of hundreds of thousands of years, a geologic longevity typically associated in public perceptions with nuclear waste. The glacial / interglacial climate cycles demonstrate that ice sheets and sea level respond dramatically to millennial-timescale changes in climate forcing. There are also potential positive feedbacks in the carbon cycle, including methane hydrates in the ocean, and peat frozen in permafrost, that are most sensitive to the long tail of the fossil fuel CO2 in the atmosphere.

David Archer

2008-02-27

457

Antarctica: geology and hydrocarbon potential  

SciTech Connect

The first impression of the hydrocarbon potential of Antarctica is generally negative. The environment is hostile and only 2% of the continent is seen through the ice. Careful study of the surprisingly ample volume of published data available on the geology and geophysics and Antarctica, coupled with the application of the principles and mechanics of plate tectonics relative to the oceans and adjacent land masses, gives a different and very positive attitude toward the hydrocarbon potential of this vast unexplored frontier area. On the basis of limited data, 21 sedimentary basins are identified for Antarctica and immediately adjacent areas. These include six onshore subglacial basins and 15 offshore basins. Excluding 11 basins considered to have little or no potential, the other 10 basins contain an estimated 16.9 million km/sup 3/ (4.05 million mi/sup 3/) of sediment having a potential hydrocarbon yield of 203 billion bbl oil equivalent. The problems associated with hydrocarbon exploration in Antarctica are formidable. Technology is adequate for seismic surveys and exploratory drilling of the Antarctic continental shelf, as concluded from current operations in the Arctic and from operating requirements of drilling rigs under construction. However, a working relationship among involved nations must first be evolved and production, storage, and transportation problems solved.

St. John, B.

1984-09-01

458

Structural geology of impact craters  

NASA Astrophysics Data System (ADS)

The formation of impact craters is a highly dynamic and complex process that subjects the impacted target rocks to numerous types of deformation mechanisms. Understanding and interpreting these styles of micro-, meso- and macroscale deformation has proved itself challenging for the field of structural geology. In this paper, we give an overview of the structural inventory found in craters of all size ranges on Earth, and look into the structures of craters on other planetary bodies. Structural features are discussed here that are caused by i) extremely high pressures and temperatures that occur during the initial passage of the shock wave through the target rock and projectile, ii) the resulting flow field in the target that excavates and ejects rock materials, and iii) the gravitationally induced modification of the crater cavity into the final crater form. A special focus is put on the effects that low-angle impacting bodies have on crater formation. We hope that this review will help both planetary scientists and structural geologists understand the deformation processes and resulting structures generated by meteorite impact.

Kenkmann, Thomas; Poelchau, Michael H.; Wulf, Gerwin

2014-05-01

459

OneGeology: Making the World’s Geological Map Data Accessible Online  

NASA Astrophysics Data System (ADS)

OneGeology (http://onegeology.org) is a successful international initiative of the geological surveys of the world and the flagship project of the ‘International Year of Planet Earth’. Its aim is to provide dynamic web access to geological map data covering the world, creating a focus for accessing geological information for everyone. Thanks to the enthusiasm and support of participating nations the initiative has progressed rapidly and geological surveys and the many users of their data are excited about this ground-breaking project. Currently 10 international geoscience organizations have endorsed the initiative and more than 109 countries have agreed to participate. OneGeology works with whatever digital format is available in each country. The target scale is 1:1 million, but the project is pragmatic and accepts a range of scales and the best available data. The initiative recognizes that different nations have differing abilities to participate and transfer of know-how to those who need it is a key aspect of the approach. A key contributor to the success of OneGeology has been its utilization of the latest new web technology and an emerging data exchange standard for geological map data called GeoSciML. GeoSciML (GeoScience Markup Language) is a schema written in GML (Geography Markup Language) for geological data. GeoSciML has the ability to represent both the geography (geometries e.g. polygons, lines and points) and geological attribution in a clear and structured format. OneGeology was launched March 2007 at the inaugural workshop in Brighton England. At that workshop the 43 participating nations developed a declaration of a common objective and principles called the “Brighton Accord” (http://onegeology.org/what_is/accord.html) . Work was initiated immediately and the resulting OneGeology Portal was launched at the International Geological Congress in Oslo in August 2008 by Simon Winchester, author of “The Map that Changed the World”. Since the successful launch, OneGeology participants have continued working both to increase national participation and content, and to put in place a more formal governance structure to oversee the long term evolution of the initiative. OneGeology is an example of collaboration in action and is both multilateral and multinational. In 2007, a group of motivated geoscientists and data managers identified an opportunity and took the initiative to engage their peers to work in concert to achieve a shared objective. OneGeology has facilitated collaborative development of an Internet site that provides unprecedented online access to global geological map data.

Broome, H.; Jackson, I.; Robida, F.; Thorleifson, H.

2009-12-01

460

OneGeology-Europe - The Challenges and progress of implementing a basic geological infrastructure for Europe  

NASA Astrophysics Data System (ADS)

OneGeology-Europe is making geological spatial data held by the geological surveys of Europe more easily discoverable and accessible via the internet. This will provide a fundamental scientific layer to the European Plate Observation System Rich geological data assets exist in the geological survey of each individual EC Member State, but they are difficult to discover and are not interoperable. For those outside the geological surveys they are not easy to obtain, to understand or to use. Geological spatial data is essential to the prediction and mitigation of landslides, subsidence, earthquakes, flooding and pollution. These issues are global in nature and their profile has also been raised by the OneGeology global initiative for the International Year of Planet Earth 2008. Geology is also a key dataset in the EC INSPIRE Directive, where it is also fundamental to the themes of natural risk zones, energy and mineral resources. The OneGeology-Europe project is delivering a web-accessible, interoperable geological spatial dataset for the whole of Europe at the 1:1 million scale based on existing data held by the European geological surveys. Proof of concept will be applied to key areas at a higher resolution and some geological surveys will deliver their data at high resolution. An important role is developing a European specification for basic geological map data and making significant progress towards harmonising the dataset (an essential first step to addressing harmonisation at higher data resolutions). It is accelerating the development and deployment of a nascent international interchange standard for geological data - GeoSciML, which will enable the sharing and exchange of the data within and beyond the geological community within Europe and globally. The geological dataset for the whole of Europe is not a centralized database but a distributed system. Each geological survey implements and hosts an interoperable web service, delivering their national harmonized geological data. These datasets are registered in a multilingual catalogue, who is one the main part of this system. This catalogue and a common metadata profile allows the discovery of national geological and applied geological maps at all scapes, Such an architecture is facilitating re-use and addition of value by a wide spectrum of users in the public and private sector and identifying, documenting and disseminating strategies for the reduction of technical and business barriers to re-use. In identifying and raising awareness in the user and provider communities, it is moving geological knowledge closer to the end-user where it will have greater societal impact and ensure fuller exploitation of a key data resource gathered at huge public expense. The project is providing examples of best practice in the delivery of digital geological spatial data to users, e.g. in the insurance, property, engineering, planning, mineral resource and environmental sectors. The scientifically attributed map data of the project will provide a pan-European base for science research and, importantly, a prime geoscience dataset capable of integration with other data sets within and beyond the geoscience domain. This presentation will demonstrate the first results of this project and will indicate how OneGeology-Europe is ensuring that Europe may play a leading role in the development of a geoscience spatial data infrastructure (SDI) globally.

Asch, Kristine; Tellez-Arenas, Agnes

2010-05-01

461

A LONG, LONG time ago: geologic timescales  

NSDL National Science Digital Library

Each student randomly picks a card with a geologic event (written description and an image) on it. A timeline has 11 events, not including the formation of the Earth and today. Students attach their event where they think it should go on a 45.5' timeline (in the hallway) made out of paper adding tape and mark the location on the timeline. They return to the classroom and receive a list of age dates for each event. Each group figures out the scale (1 foot = 100 million years) and then moves their events to the correct locations. Students are asked how the position of the events changed, and answer other questions that reinforce the difference between human timescales and geologic timescales. The powerpoint file below contains a template for making geologic event labels for the index cards. Instructors can tailor the geologic event list to fit their course.

Johnson, Elizabeth

462

Paleogeography and Geologic Evolution of North America  

NSDL National Science Digital Library

The site consists of images showing how current research suggests the North American continent has developed over the last 550 million years. The 41 maps show projections of how the continent looked at particular points in geologic time.

Dr. Ron Blakey

463

Reports of planetary geology program, 1983  

NASA Technical Reports Server (NTRS)

Several areas of the Planetary Geology Program were addressed including outer solar system satellites, asteroids, comets, Venus, cratering processes and landform development, volcanic processes, aeolian processes, fluvial processes, periglacial and permafrost processes, geomorphology, remote sensing, tectonics and stratigraphy, and mapping.

Holt, H. E. (compiler)

1984-01-01

464

Nevada Bureau of Mines and Geology  

NSDL National Science Digital Library

The Nevada Bureau of Mines and Geology, part of the Mackay School of Earth Sciences and Engineering at the University of Nevada, Reno, is an active and interesting source for studying mining and geology in the Southwestern United States. The Bureau's website includes quite a bit of information that would be of interest to students, researchers, and laypeople alike. Users will find information about current research projects on a variety of topics, an archive of presentations, and many different geologic maps of Nevada. Under the site's Data/Imagery/Indexes section, visitors will find interactive maps with data on geothermal resources, mineral resources, quaternary faults, and more. Most of the information provided pertains to the state of Nevada, but would also prove useful for instructors who could use the state's rich mining and geologic history and resources as teaching examples.

465

Marine Geology and Geophysics (Program Description)  

NSF Publications Database

... aspects of geology and geophysics of the ocean basins and margins, as well as the Great Lakes. The ... and volcanic activity of the ocean basins, the continental margins, the mid-ocean ridges, and island ...

466

The geology and geophysics of Mars  

NASA Technical Reports Server (NTRS)

The current state of knowledge concerning the regional geology and geophysics of Mars is summarized. Telescopic observations of the planet are reviewed, pre-Mariner models of its interior are discussed, and progress achieved with the Mariner flybys, especially that of Mariner 9, is noted. A map of the Martian geological provinces is presented to provide a summary of the surface geology and morphology. The contrast between the northern and southern hemispheres is pointed out, and the characteristic features of the surface are described in detail. The global topography of the planet is examined along with its gravitational field, gravity anomalies, and moment of inertia. The general sequence of events in Martian geological history is briefly outlined.

Saunders, R. S.

1976-01-01

467

Reports of planetary geology program, 1980. [Bibliography  

NASA Technical Reports Server (NTRS)

This is a compilation of abstracts of reports which summarize work conducted in the Planetary Geology Program. Each report reflects significant accomplishments within the area of the author's funded grant or contract.

Holt, H. E. (compiler); Kosters, E. C. (compiler)

1980-01-01

468

Rock alteration in an experimentally imposed temperature gradient  

SciTech Connect

Rock alteration in a dynamic (circulating) hydrothermal system can be applied to any geologic system with mobile fluids. Some examples are geothermal energy extraction, ore mineral extraction, and radioactive waste isolation. While isothermal systems yield important results, polythermal (i.e., temperature gradient) systems more closely model reactions of fluid moving through a rock reservoir. The above examples will generally involve temperature gradients across the rock reservoir. A controlled temperature gradient circulation system was developed to help define these rock-fluid reactions. Six fine grained prisms are placed along the axis of a 113 cm pressure vessel. The prisms are at 72, 119, 161, 209, 270, and 310{degrees}C under flow conditions of 4 cc/min. at 1/3 kbar total pressure. In this experiment a granodiorite was reacted with initially distilled water.

Charles, R.W.

1980-01-01

469

Geologging in Oil and Gas Exploration  

Microsoft Academic Search

Geologging, which is usually referred to in the oil industry as mud logging, is a continuous monitoring system of various parameters during drilling of exploratory-assessment wells aimed for geological, gas logging, drilling, and overpressure studies. Inasmuch as it is a formation evaluation tool, monitoring of the various parameters must be carried out by geologists, who keep round-the-clock watch and plot

Bhagwan Sahay

1986-01-01

470

Volcanic geology of Tyrrhena Patera, Mars  

NASA Astrophysics Data System (ADS)

Consideration is given to the geology of Tyrrhena Patera, a large low-relief volcano in the southern cratered highlands of Mars. The general geology of Tyrrhena Patera is outlined and models for the formation of the volcano are described. Models derived from studies of terrestrial pyroclastic flows are applied to deposits at Tyrrhena Patera, showing that the characteristics of the deposits are consistent with an origin by the emplacement of gravity-driven ash flows generated by hydromagmatic or magmatic explosive eruptions.

Greeley, R.; Crown, D. A.

1990-05-01

471

Geologic investigations of outer planets satellites  

NASA Technical Reports Server (NTRS)

Four tests are examined: (1) investigation of volcanism on Io; Interim results of thermal and structural modeling of volcanism on Io are presented, (2) a study of the ancient heavily cratered regions on Ganymede, (3) a geologic comparison of the cratering record on Ganymede and Callisto, and (4) a geological and chemical investigation of internal resurfacing processes on the Saturnian satellites. Tasks 2, 3, and 4 utilize Voyager imaging data.

Strom, R. G.

1984-01-01

472

Comparison Charts of Geological Processes: Terrestrial Planets  

NSDL National Science Digital Library

This chart presents information on the geological processes (volcanism, impact cratering, tectonics, and gradation) that have affected the Earth, Moon, and the terrestrial planets. Students compare the effects these processes have had on the Moon and planets. There is also a blank chart and a sheet of notes on the geological processes that may be used in conjunction with this chart. This chart is one of the activities for the Exploring Planets in the Classroom's Introduction to the Solar System.

473

OneGeology-Europe: architecture, portal and web services to provide a European geological map  

NASA Astrophysics Data System (ADS)

OneGeology-Europe is a large ambitious project to make geological spatial data further known and accessible. The OneGeology-Europe project develops an integrated system of data to create and make accessible for the first time through the internet the geological map of the whole of Europe. The architecture implemented by the project is web services oriented, based on the OGC standards: the geological map is not a centralized database but is composed by several web services, each of them hosted by a European country involved in the project. Since geological data are elaborated differently from country to country, they are difficult to share. OneGeology-Europe, while providing more detailed and complete information, will foster even beyond the geological community an easier exchange of data within Europe and globally. This implies an important work regarding the harmonization of the data, both model and the content. OneGeology-Europe is characterised by the high technological capacity of the EU Member States, and has the final goal to achieve the harmonisation of European geological survey data according to common standards. As a direct consequence Europe will make a further step in terms of innovation and information dissemination, continuing to play a world leading role in the development of geosciences information. The scope of the common harmonized data model was defined primarily by the requirements of the geological map of Europe, but in addition users were consulted and the requirements of both INSPIRE and ‘high-resolution' geological maps were considered. The data model is based on GeoSciML, developed since 2006 by a group of Geological Surveys. The data providers involved in the project implemented a new component that allows the web services to deliver the geological map expressed into GeoSciML. In order to capture the information describing the geological units of the map of Europe the scope of the data model needs to include lithology; age; genesis and metamorphic character. For high resolution maps physical properties, bedding characteristics and weathering also need to be added. Furthermore, Geological data held by national geological surveys is generally described in national language of the country. The project has to deal with the multilingual issue, an important requirement of the INSPIRE directive. The project provides a list of harmonized vocabularies, a set of web services to deal with them, and a web site for helping the geoscientists while mapping the terms used into the national datasets into these vocabularies. The web services provided by each data provider, with the particular component that allows them to deliver the harmonised data model and to handle the multilingualism, are the first part of the architecture. The project also implements a web portal that provides several functionalities. Thanks to the common data model implemented by each web service delivering a part of the geological map, and using OGC SLD standards, the client offers the following option. A user can request for a sub-selection of the map, for instance searching on a particular attribute such as "age is quaternary", and display only the parts of the map according to the filter. Using the web services on the common vocabularies, the data displayed are translated. The project started September 2008 for two years, with 29 partners from 20 countries (20 partners are Geological Surveys). The budget is 3.25 M€, with a European Commission contribution of 2.6 M€. The paper will describe the technical solutions to implement OneGeology-Europe components: the profile of the common data model to exchange geological data, the web services to view and access geological data; and a geoportal to provide the user with a user-friendly way to discover, view and access geological data.

Tellez-Arenas, Agnès.; Serrano, Jean-Jacques; Tertre, François; Laxton, John

2010-05-01

474

Geology of the Huntsville quadrangle, Alabama  

USGS Publications Warehouse

The 7 1/2-minute Huntsville quadrangle is in south-central Madison County, Ala., and includes part of the city of Hunstville. The south, north, east, and west boundaries of the quadrangle are about 3 miles north of the Tennessee River, 15 1/2 miles south of the Tennessee line, 8 miles west of the Jackson County line, and 9 miles east of the Limestone County line. The bedrock geology of the Huntsville quadrangle was mapped by the U.S. Geological Survey in cooperation with the city of Hunstville and the Geological Survey of Alabama as part of a detailed study of the geology and ground-water resources of Madison County, with special reference to the Huntsville area. G. T. Malmberg began the geologic mapping of the county in July 1953, and completed it in April 1954. T. H. Sanford, Jr., assisted Malmberg in the final phases of the county mapping, which included measuring geologic sections with hand level and steel tape. In November 1958 Sanford, assisted by L. R. West, checked contacts and elevations in the Hunstville quadrangle; made revisions in the contact lines; and wrote the text for this report. The fieldwork for this report was completed in April 1959.

Sanford, T.H., Jr.; Malmberg, G.T.; West, L.R.

1961-01-01

475

Geologic Map of the Deer Point Quadrangle Garfield County, Utah  

E-print Network

Geologic Map of the Deer Point Quadrangle Garfield County, Utah Nicholaus David Driscoll A thesis of Geological Sciences Brigham Young University December 2012 Copyright © 2012 Nicholaus D. Driscoll All Rights. Driscoll Department of Geological Sciences, BYU Master of Science A new geologic map of the Deer Point 7

Seamons, Kent E.

476

Geology Fieldnotes: Death Valley National Park, California/Nevada  

NSDL National Science Digital Library

This Death Valley National Park site contains park geology information, park maps, photographs, visitor information, and teacher features (resources for teaching geology using National Park examples). The Park Geology section contains an exaggerated cross-section showing the vertical rise within Death Valley. A link is provided to Death Valley's expanded geology page.

477

BRIGHAM YOUNG UNIVERSITY GEOLOGY STUDIES Volume 25,Part 1  

E-print Network

#12;BRIGHAM YOUNG UNIVERSITY GEOLOGY STUDIES Volume 25,Part 1 Papers reviewing geology of field trip areas, 31st annual meeting, Rocky Mountain Section, Geological Society of America, April 28 ....................................................................................................................................................... Geology of Volcanic Rocks and Mineral Deposits in the Southern Thomas Range, Utah: A Brief Summary

Seamons, Kent E.

478

Altered Histone Modifications in Gliomas  

PubMed Central

Gliomas are the most frequently occurring primary brain tumors in adults. Although they exist in different malignant stages, including histologically benign forms and highly aggressive states, most gliomas are clinically challenging for neuro-oncologists because of their infiltrative growth patterns and inherent relapse tendency with increased malignancy. Once this disease reaches the glioblastoma multiforme stage, the prognosis of patients is dismal: median survival time is 15 months. Extensive genetic analyses of glial tumors have revealed a variety of deregulated genetic pathways involved in DNA repair, apoptosis, cell migration/adhesion, and cell cycle. Recently, it has become evident that epigenetic alterations may also be an important factor for glioma genesis. Of epigenetic marks, histone modification is a key mark that regulates gene expression and thus modulates a wide range of cellular processes. In this review, I discuss the neuro-oncological significance of altered histone modifications and modifiers in glioma patients while briefly overviewing the biological roles of histone modifications. PMID:24926467

2014-01-01

479

OneGeology-Europe Plus Initiative  

NASA Astrophysics Data System (ADS)

The Geological Surveys of the European countries hold valuable resources of geological data but, to discover, understand and use this data efficiently, a good level of standardization is essential. The OneGeology-Europe project had the aim of making geological maps at a scale 1:1M from Europe discoverable and accessible, available under a common data license and described by multilingual metainformation. A harmonized specification for basic geological map data was developed so that significant progress towards harmonizing the datasets was achieved. Responsibility for the management of the OneGeology-Europe portal has been taken by EuroGeoSurveys and provided by CGS and BRGM. Of the 34 members of EuroGeoSurveys (EGS), only 20 participated in the OneGeology-Europe project (Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Italy, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Sweden, Spain, United Kingdom), so the European area was not completely covered. At the 33rd General Meeting and Directors Workshop in 2012 it was therefore decided to establish a successor initiative OneGeology Europe Plus (1G-E+) with the purpose of extending the coverage by geological maps at a scale of 1:1 M to all the EGS member countries (including Albania, Austria, Bulgaria, Croatia, Cyprus, Greece, Iceland, Lithuania, Malta, Romania, Russia, Switzerland, Turkey, Ukraine) and also, if possible, to the other European countries (Belorussia, Bosnia and Herzegovina, Faeroe Islands, Kosovo, Latvia, Macedonia, Moldavia, Montenegro, Serbia). In order to achieve the desired result, it has been necessary for the new GSOs who intend to supply the additional 1G-E standardized services to carry out the work using their own staff and resources. The technical guidance and other support have been provided by the 1G-E+ Technical Support Team, funded from the internal budgets of their respective surveys. The team is coordinated by the Czech Geological Survey (CGS) working with the Bureau de Recherches Géologiques et Minières (BRGM), the British Geological Survey (BGS), the Geological Survey of Denmark and Greenland (GEUS) and the Geological Survey of Slovenia (GeoZS). The Geological Survey of the Netherlands (TNO) decided to provide financial support for the initiative. The Technical Support Team has been providing the technical advice required to enable the inclusion of geological maps from new countries in the 1G-E Portal using the standards developed and accepted for 1G-E. Cookbooks, on-line help and a helpdesk are provided during the work. A technical workshop was organized at which all the technical steps required to reach the target solution were presented and discussed. All newcomers must agree the existing common license that was created for downloading the 1G-E data. It should be emphasized that the results will be displayed as part of the 1G-E project and metadata/portal infrastructures. The process is still ongoing because the harmonization work for most of the countries involved has been a demanding process. Some countries are facing difficulties because of the lack of expert personnel or insufficient resources of data. Despite some problems, the 1G-E+ initiative and the work involved has contributed to effective networking and technical cooperation between the GSOs across the wider European region.

Capova, Dana; Kondrova, Lucie

2014-05-01

480

The geologic mapping of asteroid Vesta  

NASA Astrophysics Data System (ADS)

As part of NASA's Dawn mission [1,2] we conducted a geologic mapping campaign to provide a systematic, cartography-based initial characterization of the global and regional geology of asteroid Vesta. The goal of geological maps is to place observations of surface features into their stratigraphic context to develop a geologic history of the evolution of planetary surfaces. Geologic mapping reduces the complexity of heterogeneous planetary surfaces into comprehensible portions, defining and characterizing discrete material units based upon physical attributes related to the geologic processes that produced them, and enabling identification of the relative roles of various processes (impact cratering, tectonism, volcanism, erosion and deposition) in shaping planetary surfaces [3,4]. The Dawn Science Team produced cartographic products of Vesta from the Framing Camera images, including global mosaics as well as 15 regional quadrangles [5], which served as bases for the mapping. We oversaw the geologic mapping campaign during the Nominal Mission, including production of a global geologic map at scale 1:500,000 using images from the High Altitude Mapping Orbit [6] and 15 quadrangle geologic maps at scale 1:250,000 using images from the Low Altitude Mapping Orbit [7]. The goal was to support the Dawn Team by providing geologic and stratigraphic context of surface features and supporting the analysis of data from the Visible and Infrared Spectrometer (VIR) and the Gamma Ray and Neutron Detector (GRaND). Mapping was done using ArcGIS™ software, in which quadrangle mapping built on interpretations derived from the global geologic map but were updated and modified to take advantage of the highest spatial resolution data. Despite challenges (e.g., Vesta's highly sloped surface [8] deforms impact craters and produces mass movements that buries contacts), we were successfully able to map the whole surface of Vesta and identify a geologic history as represented in our maps and the resulting time-stratigraphic system and geologic timescale. Key results from the geologic mapping of Vesta include: 1) surface units are dominated by features and materials produced by two major impact events, the older Veneneia and younger Rheasilvia impacts at the south pole 2) both impacts produced a ridge-and-trough terrain as a tectonic response to the impacts, mapped as the Saturnalia Fossae and the Divalia Fossae Formations, respectively 3) stratigraphic analysis of Vesta's heavily cratered terrains show that portions of the original crust are preserved and predate the Veneneia impact 4) the Marcia impact event marks the beginning of Vesta's final stratigraphic period, including exposure of fresh bright and dark material and preservation of young bright-rayed and dark-rayed craters. We conclude that a geologic mapping campaign, including both global and regional mapping, can be conducted during the limited planetary nominal mission timeline, and is an excellent way to engage younger team members (graduate students and postdocs) in mission data analysis activities.

Williams, D.; Yingst, A.; Garry, B.

2014-07-01

481

Estimating the social value of geologic map information: A regulatory application  

USGS Publications Warehouse

People frequently regard the landscape as part of a static system. The mountains and rivers that cross the landscape, and the bedrock that supports the surface, change little during the course of a lifetime. Society can alter the geologic history of an area and, in so doing, affect the occurrence and impact of environmental hazards. For example, changes in land use can induce changes in erosion, sedimentation, and ground-water supply. As the environmental system is changed by both natural processes and human activities, the system's capacity to respond to additional stresses also changes. Information such as geologic maps describes the physical world and is critical for identifying solutions to land use and environmental issues. In this paper, a method is developed for estimating the economic value of applying geologic map information to siting a waste disposal facility. An improvement in geologic map information is shown to have a net positive value to society. Such maps enable planners to make superior land management decisions.

Bernknopf, R.L.; Brookshire, D.S.; McKee, M.; Soller, D.R.

1997-01-01

482

Geology and recognition criteria for uraniferous humate deposits, Grants Uranium Region, New Mexico. Final report  

SciTech Connect

The geology of the uraniferous humate uranium deposits of the Grants Uranium Region, northwestern New Mexico, is summarized. The most important conclusions of this study are enumerated. Although the geologic characteristics of the uraniferous humate deposits of the Grants Uranium Region are obviously not common in the world, neither are they bizarre or coincidental. The source of the uranium in the deposits of the Grants Uranium Region is not known with certainty. The depositional environment of the host sediments was apparently the mid and distal portions of a wet alluvial fan system. The influence of structural control on the location and accumulation of the host sediments is now supported by considerable data. The host sediments possess numerous important characteristics which influenced the formation of uraniferous humate deposits. Ilmenite-magnetite distribution within potential host sandstones is believed to be the simplest and most useful regional alteration pattern related to this type of uranium deposit. A method is presented for organizing geologic observations into what is referred to as recognition criteria. The potential of the United States for new districts similar to the Grants Uranium Region is judged to be low based upon presently available geologic information. Continuing studies on uraniferous humate deposits are desirable in three particular areas.

Adams, S.S.; Saucier, A.E.

1981-01-01

483

Buccal alterations in diabetes mellitus  

PubMed Central

Long standing hyperglycaemia besides damaging the kidneys, eyes, nerves, blood vessels, heart, can also impair the function of the salivary glands leading to a reduction in the salivary flow. When salivary flow decreases, as a consequence of an acute hyperglycaemia, many buccal or oral alterations can occur such as: a) increased concentration of mucin and glucose; b) impaired production and/or action of many antimicrobial factors; c) absence of a metalloprotein called gustin, that contains zinc and is responsible for the constant maturation of taste papillae; d) bad taste; e) oral candidiasis f) increased cells exfoliation after contact, because of poor lubrication; g) increased proliferation of pathogenic microorganisms; h) coated tongue; i) halitosis; and many others may occur as a consequence of chronic hyperglycaemia: a) tongue alterations, generally a burning mouth; b) periodontal disease; c) white spots due to demineralization in the teeth; d) caries; e) delayed healing of wounds; f) greater tendency to infections; g) lichen planus; h) mucosa ulcerations. Buccal alterations found in diabetic patients, although not specific of this disease, have its incidence and progression increased when an inadequate glycaemic control is present. PMID:20180965

2010-01-01

484

Phosphoinositides alter lipid bilayer properties.  

PubMed

Phosphatidylinositol-4,5-bisphosphate (PIP2), which constitutes ?1% of the plasma membrane phospholipid, plays a key role in membrane-delimited signaling. PIP2 regulates structurally and functionally diverse membrane proteins, including voltage- and ligand-gated ion channels, inwardly rectifying ion channels, transporters, and receptors. In some cases, the regulation is known to involve specific lipid-protein interactions, but the mechanisms by which PIP2 regulates many of its various targets remain to be fully elucidated. Because many PIP2 targets are membrane-spanning proteins, we explored whether the phosphoinositides might alter bilayer physical properties such as curvature and elasticity, which would alter the equilibrium between membrane protein conformational states-and thereby protein function. Taking advantage of the gramicidin A (gA) channels' sensitivity to changes in lipid bilayer properties, we used gA-based fluorescence quenching and single-channel assays to examine the effects of long-chain PIP2s (brain PIP2, which is predominantly 1-stearyl-2-arachidonyl-PIP2, and dioleoyl-PIP2) on bilayer properties. When premixed with dioleoyl-phosphocholine at 2 mol %, both long-chain PIP2s produced similar changes in gA channel function (bilayer properties); when applied through the aqueous solution, however, brain PIP2 was a more potent modifier than dioleoyl-PIP2. Given the widespread use of short-chain dioctanoyl-phosphoinositides, we also examined the effects of diC8-phosphoinositol (PI), PI(4,5)P2, PI(3,5)P2, PI(3,4)P2, and PI(3,4,5)P3. The diC8 phosphoinositides, except for PI(3,5)P2, altered bilayer properties with potencies that decreased with increasing head group charge. Nonphosphoinositide diC8