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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


The mineral chemistry of hydrothermally altered and metamorphosed wall-rocks at the Stollberg Fe-Pb-Zn-Mn(-Ag) deposit, Bergslagen, Sweden  

NASA Astrophysics Data System (ADS)

The c. 1.9 Ga old Stollberg sulphide and Mnrich skarn iron ores and sulphide ores in Bergslagen, south-central Sweden are hosted by hydrothermally altered and metamorphosed felsic volcanic and volcaniclastic rocks. The ores are underlain by comformable alteration zones characterized by albite-gedrite-quartz and biotite-muscovite-plagioclase-K-feldspar-quartz +/- garnet assemblages. The present mineralogies are interpreted as medium-grade metamorphic equivalents to the original alteration mineral assemblages. PT-conditions during prograde regional metamorphism are semiquantatively determined to be 510 to 560 °C at approximately 3 kbar. With increasing modal content of gedrite and biotite in the alteration zones, the Mg/Fe ratios and XMg's in octahedral positions of these minerals also increase. In the gedrite-bearing strata, whole-rock Mg/Fe ratios remain constant, whereas in the biotite-rich unit the wholerock Mg/Fe trend is parallel to that of the biotites. The trends in the metamorphic mineral composition are interpreted to be a product of original changes in fluid composition during the evolution of a sub-seafloor hydrothermal system. During the initial stage of alteration, Fe-Mn-rich fluids altered the rocks, and during a later stage, the fluids became more Mg-rich, possibly due to entrainment of fresh seawater, and the alteration zones became relatively more Mg-rich. Sulphide precipitation was contemperaneous with Mg metasomatism, suggesting base metal precipitation was a function of the mixing of cool seawater with hydrothermal fluid. It is proposed that early hydrothermal alteration was associated with the deposition of areally extensive Fe-oxide formation, and that Mg metasomatism defines a second stage of hydrothermal activity during which sulphide mineralization overprinted the earlier formed Fe-oxide deposit.

Ripa, M.



Comparison of metasomatic reactions between a common CO2-rich vein fluid and diverse wall rocks: intensive variables, mass transfers, and Au mineralization at Alleghany, California  

USGS Publications Warehouse

The gold deposits at Alleghany, California, are typical of many epigenetic gold-bearing hydrothermal vein systems in metamorphic terranes worldwide. Detailed analyses of alteration halos in serpentinite, mafic amphibolite, and granite wall rocks at Alleghany indicate that widely contrasting deposit types, ranging from fuchsite-carbonate schists to pyrite-albitites, resulted when different wall rocks interacted with the same externally derived CO2-rich hydrothermal vein fluid. Patterns of element redistribution within halos and among lithologic units suggest a complex process involving fluid flow along vein fractures and diffusion (?? infiltration) normal to the veins. Wall rocks locally controlled both the directions and magnitudes of chemical fluxes across vein walls. -from Author

Böhlke, J.K.



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



A Mechanism for High Wall-rock Velocities in Rockbursts  

Microsoft Academic Search

-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

A. McGarr



Aqueous alteration of VHTR fuels particles under simulated geological conditions  

NASA Astrophysics Data System (ADS)

Very High Temperature Reactor (VHTR) fuels consist of the bistructural-isotropic (BISO) or tristructural-isotropic (TRISO)-coated particles embedded in a graphite matrix. Management of the spent fuel generated during VHTR operation would most likely be through deep geological disposal. In this framework we investigated the alteration of BISO (with pyrolytic carbon) and TRISO (with SiC) particles under geological conditions simulated by temperatures of 50 and 90 °C and in the presence of synthetic groundwater. Solid state (scanning electron microscopy (SEM), micro-Raman spectroscopy, electron probe microanalyses (EPMA) and X-ray photoelectron spectroscopy (XPS)) and solution analyses (ICP-MS, ionique chromatography (IC)) showed oxidation of both pyrolytic carbon and SiC at 90 °C. Under air this led to the formation of SiO2 and a clay-like Mg-silicate, while under reducing conditions (H2/N2 atmosphere) SiC and pyrolytic carbon were highly stable after a few months of alteration. At 50 °C, in the presence and absence of air, the alteration of the coatings was minor. In conclusion, due to their high stability in reducing conditions, HTR fuel disposal in reducing deep geological environments may constitute a viable solution for their long-term management.

Ait Chaou, Abdelouahed; Abdelouas, Abdesselam; Karakurt, Gökhan; Grambow, Bernd



HiRISE Images of Layered Deposits in West Candor Chasma, Mars (I): Wall Rock Relations, Enigmatic Ridges, and Possible Dikes  

NASA Astrophysics Data System (ADS)

Light-toned layers on the trough floor are superposed on the walls, not exhumed. Wall-rock benches could be shorelines, suggesting former lakes. Dark ridges in Ceti Mensa, if altered dikes, would suggest a volcanic origin for this edifice.

Lucchitta, B. K.



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.



Foam flow through a transparent rough-walled rock fracture  

SciTech Connect

This paper presents an experimental study of nitrogen, water, and aqueous foam flow through a transparent replica of a natural rough-walled rock fracture with a hydraulic aperture of roughly 30 {mu}m. It is established that single-phase flow of both nitrogen and water is well described by analogy to flow between parallel plates. Inertial effects caused by fracture roughness become important in single-phase flow as the Reynolds number approaches 1. Foam exhibits effective control of gas mobility. Foam flow resistances are approximately 10 to 20 times greater than those of nitrogen over foam qualities spanning from 0.60 to 0.99 indicating effective gas-mobility control. Because previous studies of foam flow have focused mainly upon unfractured porous media, little information is available about foam flow mechanisms in fractured media. The transparency of the fracture allowed flow visualization and demonstrated that foam rheology in fractured media depends upon bubble shape and size. Changes in flow behavior are directly tied to transitions in bubble morphology.

Kovscek, A.; Tretheway, D.; Radke, C. [and others



Scale of pluton\\/wall rock interaction near May Lake, Yosemite National Park, CA, USA  

Microsoft Academic Search

Interaction of magma with wall rock is an important process in igneous petrology, but the mechanisms by which interactions\\u000a occur are poorly known. The western outer granodiorite of the Cretaceous Tuolumne Intrusive Suite of Yosemite National Park,\\u000a California, intruded a variety of metasedimentary and igneous wall rocks at 93.1 Ma. The May Lake metamorphic screen is a\\u000a metasedimentary remnant whose contact

Ryan D. Mills; Allen F. Glazner; Drew S. Coleman



Sulfide solubilities in Alteration-controlled Systems  

USGS Publications Warehouse

Solubilities of sphalerite (ZnS) and galena (PbS) were determined at 300?? to 500??C and 1000 bars total pressure in a chemical environment buffered by silicate mineral equilibria. Chloride solutions and muscovite-bearing assemblages characteristic of hydrothermal wall-rock alteration were used; weak acidities at temperature were therefore involved. The metal concentrations encountered tended to be higher than those observed in high bisulfide-H2S systems at neutral to weakly basic pH used in most previous experimentation; the chemical conditions of the work, although not completely satisfactory, are geologically more realistic than previous experimentation done in the basic-pH region.

Hemley, J.J.; Meyer, C.; Hodgson, C.J.; Thatcher, A.B.



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

E-print Network

, respectively. This project explored the natural geological response of the system to these alterations using data from side scan sonar, sediment grab samples, and vibracores. In highly urbanized northern Naples Bay, benthic substrates consist primarily of muddy...

Fielder, Bryan Robert



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.



Geology, alteration, age, and origin of iron oxide-apatite deposits in Upper Eocene quartz monzonite, Zanjan district, NW Iran  

NASA Astrophysics Data System (ADS)

Iron oxide-apatite deposits are present in Upper Eocene pyroxene-quartz monzonitic rocks of the Zanjan district, northwestern Iran. Mineralization occurred in five stages: (1) deposition of disseminated magnetite and apatite in the host rock; (2) mineralization of massive and banded magnetite ores in veins and stockwork associated with minor brecciation and calcic alteration of host rocks; (3) deposition of sulfide ores together with potassic alteration; (4) formation of quartz and carbonate veins and sericite, chlorite, epidote, silica, carbonate, and tourmaline alteration; and (5) supergene alteration and weathering. U-Pb dating of monazite inclusions in the apatite indicates an age of 39.99 ± 0.24 Ma, which is nearly coeval with the time of emplacement of the host quartz monzonite, supporting the genetic connection. Fluid inclusions in the apatite have homogenization temperatures of about 300 °C and oxygen isotopic compositions of the magnetite support precipitation from magmatic fluids. Late-stage quartz resulted from the introduction of a cooler, less saline, and isotopically depleted fluid. The iron oxide-apatite deposits in the Tarom area of the Zanjan district are typical of a magmatic-hydrothermal origin and are similar to the Kiruna-type deposits with respect to mineral assemblages, fabric and structure of the iron ores, occurrence of the ore bodies, and wall rock alteration.

Nabatian, Ghasem; Ghaderi, Majid; Corfu, Fernando; Neubauer, Franz; Bernroider, Manfred; Prokofiev, Vsevolod; Honarmand, Maryam



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


Pyroclasts and fragmentation: `misdirection' from size distributions for wall-rock particles (Invited)  

NASA Astrophysics Data System (ADS)

A principal tenet of explosive volcanology is that the size distribution of pyroclasts is a sensitive indicator of fragmentation mechanism and eruptive style. However lithic pyroclasts in many explosive eruptions are not fragmented by the explosion but instead are derived from collapse or erosion of the walls of the vent and shallow conduit. Under these conditions the size distribution of this component is often ‘inherited’ and reflects pre-existing properties of the wall rock. We demonstrate this for two basaltic eruptions of widely contrasting mass discharge rate and style. The basaltic Plinian eruption of Tarawera, New Zealand in 1886 lasted 6 hours and had a time averaged mass discharge rate of 10E+8 kg/s. Eight impulsive explosions of Halema`uma`u crater, Kilauea in 2008 had eruptions rates of 10E+3 to 10E+4 kg/s and durations of tens of seconds. In both cases the wall rock component of the ejecta was derived from failures of unstable vent walls. In the case of Halema`uma`u only the finer-grained part of this ‘primary’ clast population was incorporated into the eruption jet. The clue to inferring such processes for older eruptions is within in the grain size and componentry data, in the decoupling and independence of the wall-rock and juvenile clast populations. In both of our case studies, neither wall rock nor whole-deposit grain size characteristics can be used to constrain and compare the intensity of explosions, or define eruptive style.

Houghton, B. F.; Carey, R. J.; Swanson, D.



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.



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)




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.



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.



Magma dynamics and wall-rock composition control the environmental impact of magmatic events  

NASA Astrophysics Data System (ADS)

A key control on the destructive consequences of the emplacement of large igneous provinces such as Siberia and Deccan is the type of sedimentary rock in basins beneath the flood basalts. Contact metamorphism around intrusions in carbonates (dolostones or limestones), sulphates (evaporites), coal or organic-rich shale generates large quantities of greenhouse and toxic gases (CO2, CH4, SO2) which subsequently vent to the atmosphere and cause global warming and mass extinctions. Recently we demonstrated that the release of sediment-derived gases had a far greater impact on the environment than the emission of magmatic gases. Here we compare the effects of contact metamorphism of different types of carbonated sediments. We estimate that about 220 kg of CO2 were released per ton of metamorphosed dolomite in Sichuan basin around the plumbing system of Emeishan large igneous province in China. New structural studies show that during emplacement of the main intrusion, multiple generations of mafic dykes invaded the marbles of the lower metamorphic aureole. These dykes reacted extensively with the marble, and the magma actively assimilated wall-rock dolostone, a process that potentially released the entire CO2 budget of the assimilated carbonate, or 477 kg/ton. We compare this result with a second case, the Aguablanca intrusion in Spain, where mafic magma intruded limestones and shales. Contact metamorphism of pure limestone produced very little CO2 (less than 50 kg of CO2 per ton of pure limestone) whereas, in impure dolostones, the presence of silica or clay allowed the formation of calc-silicate minerals and strongly increased the CO2 yield, to140 kg CO2 per ton. In contrast, studies by Svensen and coworkers of sills in the Karoo province reveal lower rates of emission, mainly from decomposition of hydrocarbons around passively emplaced intrusions. Therefore, to understand the full impact on environment of the release of thermogenic gases during a major magmatic event, we need to take into account both the types of wall rock and dynamics of magma emplacement.

Arndt, N.; Ganino, C.; Pêcher, A.; Chauvel, C.; Zhou, M.; Tornos, F.



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

SciTech Connect

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 criteria. Phase occupancy and permeability are derived by assuming a parallel-plate approximation for suitably small subregions in the fracture plane. For log-normal aperture distributions, a simple approximation to fracture capillary pressure is obtained in closed form; it is found to resemble the typical shape of Leverett's j-function. Wetting and non-wetting phase relative permeabilities are calculated by numerically simulating single phase flows separately in the wetted and non-wetted pore spaces. Illustrative examples indicate that relative permeabilities depend sensitively on the nature and range of spatial correlation between apertures. It is also observed that interference between fluid phases flowing in a fracture tends to be strong, with the sum of wetting and nonwetting phase relative permeabilities being considerably less than 1 at intermediate saturations.

Pruess (ed), K.; Tsang, Y.W.



The stable isotope geochemistry of acid sulfate alteration  

USGS Publications Warehouse

Acid sulfate wall-rock alteration, characterized by the assemblage alunite + kaolinite + quartz ?? pyrite, results from base leaching by fluids concentrated in H2SO4. Requisite amounts of H2SO4 can be generated by different mechanisms in three principal geologic environments: 1) by atmospheric oxidation of sulfides in the supergene environment, 2) by atmospheric oxidation at the water table in the steam-heated environment of H2S released by deeper, boiling fluids, and 3) by the disproportionation of magmatic SO2 to H2S and H2SO4 during condensation of a magmatic vapor plume at intermediate depths in magmatic hydrothermal environments in silicic and andesitic volcanic terranes. In addition, coarse vein alunite may form in a magmatic steam environment. -from Authors

Rye, R.O.; Bethke, P.M.; Wasserman, M.D.



Microbially Mediated Glass Alteration in the Geological Record: Textural clues for Microbial Functions.  

NASA Astrophysics Data System (ADS)

Fe and Mn oxidizing microbes interact with their environment through the microbially mediated formation of Fe/Mn oxides and through the corrosion textures they may leave behind in the solids they colonize and from which they extract nutrients. Understanding the geo-biology of Fe and Mn oxidation may focus on the study of the microbes themselves, the mineral products, its biocorrosion features and the relationships between these types of observations. We have reviewed our own data on glass bio-corrosion and in particular the wider literature on microbial mineral tunneling to develop a two stage biocorrosion model for volcanic glass that offers feedback for our understanding of the mechanisms and the dynamics of microbial dissolution. Traces of microbially mediated dissolution of volcanic glass are commonly observed in volcanic glass found in submarine volcanoes on the seafloor, and in uplifted submarine volcanoes of almost any geological age back to the origin of life. Two main bioalteration textures care observed, granular and tubular. Based on a comparison of these features in particular with tunneling by ectomycorrhizal fungi, we propose two distinct types of biocorrosion that affects glass: (1) Granular alteration textures, made up of colonies of microbe-sized, near spherical mineral - filled cavities that form irregular clusters ranging to a tens of micron thick bands at the glas surfaces. These granular textures are interpreted as the result of microbial colonization. accompanied by dissolution of the glass in their contact surface, deposition of authigenic minerals and the formation of a biofilm, that eventually seals the glass from easy access by seawater for hydration, or from microbes accessing Fe (II) in the glass. (2) The most spectacular bioalteration feature, repesented by the formation of tubes cannot be easily formed by the former mechanism because near spherical, individual microbes are likely not to produce the directionality that is required to produce the near linear or sometimes coiled tubes. Instead, we envision the activity of hyphae-like organelles or filaments, that may radiate out from a host body located in direct contact with circulating water, possibly penetrating a biofilm and entering/drilling into the fresh glass. Such microdrilling is well described in soils, where hyphae can slowly drill into silicates, in a process that takes about 1000 years to become visible as tunnels.

Staudigel, H.; Furnes, H.; McLoughlin, N.; Banerjee, N.




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



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



Opportunity In Situ Geologic Context of Aqueous Alteration Along Offsets in the Rim of Endeavour Crater  

NASA Technical Reports Server (NTRS)

Mars Exploration Rover Opportunity traversed 7.9 km and 27 degrees of arc along the rim of the 22 km-diameter Noachian "Endeavour" impact crater since its arrival 1200 sols ago. Areas of aqueous and low-grade thermal alteration, and changes in structure, attitude, and macroscopic texture of outcrops are notable across several discontinuities between segments of the crater rim. The discontinuities and other post-impact joints and fractures coincide with sites of apparent deep fluid circulation processes responsible for thermal and chemical alteration of local outcrops.

Crumpler, L. S.; Arvidson, R. E.; Farrand, W. H.; Golombek, M. P.; Grant, J. A.; Ming, D. W.; Mittlefehldt, D. W.; Parker, T. J.



Accounting for geochemical alterations of caprock fracture permeability in basin-scale models of leakage from geologic CO2 reservoirs  

NASA Astrophysics Data System (ADS)

Climate mitigation, public acceptance and energy, markets demand that the potential CO2 leakage rates from geologic storage reservoirs are predicted to be low and are known to a high level of certainty. Current approaches to predict CO2 leakage rates assume constant permeability of leakage pathways (e.g., wellbores, faults, fractures). A reactive transport model was developed to account for geochemical alterations that result in permeability evolution of leakage pathways. The one-dimensional reactive transport model was coupled with the basin-scale Estimating Leakage Semi-Analytical (ELSA) model to simulate CO2 and brine leakage through vertical caprock pathways for different CO2 storage reservoir sites and injection scenarios within the Mt. Simon and St. Peter sandstone formations of the Michigan basin. Mineral dissolution in the numerical reactive transport model expands leakage pathways and increases permeability as a result of calcite dissolution by reactions driven by CO2-acidified brine. A geochemical model compared kinetic and equilibrium treatments of calcite dissolution within each grid block for each time step. For a single fracture, we investigated the effect of the reactions on leakage by performing sensitivity analyses of fracture geometry, CO2 concentration, calcite abundance, initial permeability, and pressure gradient. Assuming that calcite dissolution reaches equilibrium at each time step produces unrealistic scenarios of buffering and permeability evolution within fractures. Therefore, the reactive transport model with a kinetic treatment of calcite dissolution was coupled to the ELSA model and used to compare brine and CO2 leakage rates at a variety of potential geologic storage sites within the Michigan basin. The results are used to construct maps based on the susceptibility to geochemically driven increases in leakage rates. These maps should provide useful and easily communicated inputs into decision-making processes for siting geologic CO2 storage sites.

Guo, B.; Fitts, J. P.; Dobossy, M.; Bielicki, J. M.; Peters, C. A.



Wall-rock control of cortain pitchblende deposits in Golden Gate Canyon, Jefferson County, Colorado  

USGS Publications Warehouse

Carbonate veins cutting pre-Cambrian metamorphic rocks in Golden Gate Canyon contain pitchblende and base-metal sulfides. The veins occupy extensive faults of Laramide age but normally contain pitchblende only where the cut hornblende gneiss. At the Union Pacific prospect, which was studied in detail, pitchblende, hermatite, and some ankerite formed in advance of sulfides, except possibly for minor pyrite. Base-metal sulfides and the bulk of ankerite-calcite vein-filling were deposited after the pitchblende. Chemical analyses show a high ferrous iron content in the hornblende gneiss in contrast to low ferrous iron in the adjacent biotite gneiss. It is hypothesized that ferrous iron released by alteration of hornblende was partly oxidized to hematite by the ore-bearing solutions and, contemporaneously, uranium was reduced and deposited as pitchblende. In other veins, biotite or iron sulfides may have been similarly effective in precipitating pitchblende. Apparently both the ferrous ion and the sulfide ion can serve as reducing agents and control pitchblende deposition. It is suggested that conditions particularly favorable for uranium deposition are present where uranium-bearing solutions had access to rocks rich in ferrous iron or pre-existing sulfides.

Adams, John W.; Stugard, Frederick, Jr.



Identification of hydrated silicate minerals on Mars using MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration  

USGS Publications Warehouse

The Noachian terrain west of the Isidis basin hosts a diverse collection of alteration minerals in rocks comprising varied geomorphic units within a 100,000 km2 region in and near the Nili Fossae. Prior investigations in this region by the Observatoire pour l'Min??ralogie, l'Eau, les Glaces, et l'Activit?? (OMEGA) instrument on Mars Express revealed large exposures of both mafic minerals and iron magnesium phyllosilicates in stratigraphic context. Expanding on the discoveries of OMEGA, the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard the Mars Reconnaissance Orbiter (MRO) has found more spatially widespread and mineralogically diverse alteration minerals than previously realized, which represent multiple aqueous environments. Using CRISM near-infrared spectral data, we detail the basis for identification of iron and magnesium smectites (including both nontronite and more Mg-rich varieties), chlorite, prehnite, serpentine, kaolinite, potassium mica (illite or muscovite), hydrated (opaline) silica, the sodium zeolite analcime, and magnesium carbonate. The detection of serpentine and analcime on Mars is reported here for the first time. We detail the geomorphic context of these minerals using data from high-resolution imagers onboard MRO in conjunction with CRISM. We find that the distribution of alteration minerals is not homogeneous; rather, they occur in provinces with distinctive assemblages of alteration minerals. Key findings are (1) a distinctive stratigraphy, in and around the Nili Fossae, of kaolinite and magnesium carbonate in bedrock units always overlying Fe/Mg smectites and (2) evidence for mineral phases and assemblages indicative of low-grade metamorphic or hydrothermal aqueous alteration in cratered terrains. The alteration minerals around the Nili Fossae are more typical of those resulting from neutral to alkaline conditions rather than acidic conditions, which appear to have dominated much of Mars. Moreover, the mineralogic diversity and geologic context of alteration minerals found in the region around the Nili Fossae indicates several episodes of aqueous activity in multiple distinct environments. Copyright 2009 by the American Geophysical Union.

Ehlmann, B.L.; Mustard, J.F.; Swayze, G.A.; Clark, R.N.; Bishop, J.L.; Poulet, F.; Des Marais, D.J.; Roach, L.H.; Milliken, R.E.; Wray, J.J.; Barnouin-Jha, O.; Murchie, S.L.



Geological and geochemical constraints on genesis of the Liziyuan gold-dominated polymetal deposit, western Qinling orogen, central China  

Microsoft Academic Search

The Liziyuan gold deposit, located on the northern margin of the western Qinling orogen (WQO), consists of five mineralized sites hosted by metavolcanic rocks, and one hosted by the Tianzishan monzogranite. Orebodies mainly occur as lenticular veins along NW-striking dextral ductile strike–slip shear zones. Major wall rock alteration includes silicification, pyritization, and carbonation, progressively increasing in intensity towards the orebodies.

Tao Yang; Laimin Zhu; Guowei Zhang; Fei Wang; Rukun Lu; Jichao Xia; Yongqiang Zhang



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


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.



Stable isotope and chemical systematics of pseudotachylyte and wall rock, Homestake shear zone, Colorado, USA: Meteoric fluid or rock-buffered conditions during coseismic fusion?  

NASA Astrophysics Data System (ADS)

A hydrous fluid phase is critical in controlling effective stress and fault mechanics, and influencing the mineralogy and strength of materials within fault zones. Oxygen and hydrogen isotope and chemical analysis of wall rock gneiss, pseudotachylyte, and selected minerals in gneiss and pseudotachylyte from the Homestake shear zone was used to assess whether melting occurred in the presence of meteoric water or involved only minor amounts of H2O derived from micas in wall rock gneiss. Bulk pseudotachylyte has slightly lower ?18OSMOW than the whole rock protolith. ?D for one bulk pseudotachylyte is essentially identical to biotite in gneiss; ?D for two samples is lower by ˜20‰. Bulk pseudotachylyte has lower SiO2 and K2O, and higher Al2O3, FeO, MgO, CaO, and H2O, than gneiss. The lower SiO2 of pseudotachylyte compared to gneiss is explained by physical segregation of 25 to 72 volume % of quartz clasts from the mobile melt phase. Samples of gneiss and pseudotachylyte define a SiO2-?18O mixing line between quartz and the most SiO2- and 18O-depleted pseudotachylyte. Physical segregation of quartz (highest oxygen isotope composition in the pseudotachylyte-gneiss system) accounts for the slightly lower oxygen isotope composition of bulk pseudotachylyte relative to gneiss. The similar ?D of pseudotachylyte and biotite from gneiss in one sample is consistent with dehydration melting of biotite during frictional heating and dissolution of biotite-derived H2O in the melt. Late devitrification of glass and formation of greater amounts of fine-grained muscovite, accompanied by 10-30% loss of hydrogen as H2O, results in lower ?D values in other samples. In general, melt generation occurred in a fault zone closed to infiltration of meteoric water. There was no free, H2O-rich pore fluid present at the time of slip to potentially influence the behavior of the fault.

Moecher, David P.; Sharp, Zachary D.



Subseafloor hydrothermal alteration during the Early Proterozoic at Garpenberg, Central Sweden  

NASA Astrophysics Data System (ADS)

The Early Proterozoic sulfide deposit at Garpenberg is located in the metallogenetic province of central Sweden. It is a strata-bound massive sulfide deposit contained in a supracrustal sequence of mainly acid metavolcanic rocks. Stratiform Zn-Pb-Cu mineralization is underlain by Cu-bearing stockwork ore and an extensive alteration zone. The sulfide ores and their altered wall rocks were formed by subseafloor hydrothermal activity. The alteration pattern observed in the wall rocks of this deposit is consistent with a hydrothermal system where the fluid consists mainly of seawater and a high water/rock mass ratio predominates. The hydrothermal activity caused the destruction of the primary mineralogy, mainly feldspars, and a general redistribution of the chemical elements in the altered wall rocks which were principally depleted in Ca, Na and Eu and enriched in Mg. Eu was redeposited with the ore metals near or at the seafloor and Ca was deposited as limestone. Most of the major and trace elements show large mobility during the alteration; only Ti, Zr, Y and REE (excluding Eu) behaved as relatively immobile elements.

Vivallo, W.



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))



©2007 Society of Economic Geologists, Inc. Economic Geology, v. 102, pp. 1079–1089 Effects of Mother Lode-Type Gold Mineralization on 187 Os / 188 Os and Platinum Group Element Concentrations in Peridotite: Alleghany District, California  

E-print Network

Osmium isotope compositions and concentrations of Re, platinum group elements (PGE), and Au were determined for host peridotites (serpentinites and harzburgites) and hydrothermally altered ultramafic wall rocks associated with Mother Lode-type hydrothermal gold-quartz vein mineralization in the

Richard J. Walker; John Karl Böhlke; William F. Mcdonough; Ji Li


Vesta's Geological Features  

NASA Astrophysics Data System (ADS)

Vesta’s diverse geology exhibits impact basins and craters of all sizes and unusual shapes, ejecta blankets, large troughs, impact basins, enigmatic dark material, and considerable evidence for mass wasting and surface alteration processes.

Jaumann, R.; Russell, C. T.; Raymond, C. A.; Pieters, C. M.; Yingst, R. A.; Williams, D. A.; Buczkowski, D. L.; Schenk, P.; De Sanctis, M. C.



Geological SciencesGeological Sciences Geological EngineeringGeological Engineering  

E-print Network

Geological SciencesGeological Sciences Geological EngineeringGeological Engineering Geosciences Careers in the ik ou ve n ver see t b f rel e y ' e n i e o ! Department of Geological Sciences and Geological Engineering Queen's University See the World Geological Sciences Arts and Science Faculty

Ellis, Randy


A fractured roman glass block altered for 1800 years in seawater: Analogy with nuclear waste glass in a deep geological repository  

NASA Astrophysics Data System (ADS)

Fractured archaeological glass blocks altered 1800 years in seawater are investigated because of their morphological analogy with vitrified nuclear waste. They provide an opportunity for understanding glass alteration in variable confined media (cracks), by studying an actual ancient system in a known stable natural environment. Characterization of the crack network from two-dimensional trace maps (length, alteration thickness, orientation) allows us to determine the three-dimensional geometric parameters (crack density, fracture ratio) and the percentage of alteration, using stereological relations. This methodology could be applied to nuclear glass. From a representative archaeological glass block, we showed that the surface developed by the cracks is 86 ± 27 times greater than the geometric surface but the volumetric alteration is 12.2 ± 4.1%, which is only 12 times greater than the volumetric alteration of the block periphery (about 1 vol%). This unexpected low value is explained by the large variation of the alteration thicknesses in the different types of cracks in relation with their location in the block. The alteration thickness is usually smaller in the internal zone than in the border zone. The alteration layers resulted from three main mechanisms (interdiffusion, glass dissolution, and secondary phase precipitation) leading to two different alteration products (a sodium-depleted layer and mainly a Mg-smectite). Geometric parameters such as the glass surface area/solution volume ratio and transport parameters (renewal of the alteration solution) strongly affected the glass dissolution kinetics. The confined conditions and the diffusive transport of reactive species favor low alteration kinetics. The precipitation of secondary phases also results in sealing of the cracks. Consequently, although it is not known if subcritical crack growth occurred, internal cracks account for only a minor contribution to the overall alteration. These results improve our understanding of alteration in cracks for assessing the predominant physical and chemical parameters that must be considered in long-term nuclear glass modeling.

Verney-Carron, Aurelie; Gin, Stephane; Libourel, Guy



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.



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.



Identification of hydrated silicate minerals on Mars using MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration  

Microsoft Academic Search

The Noachian terrain west of the Isidis basin hosts a diverse collection of alteration minerals in rocks comprising varied geomorphic units within a 100,000 km2 region in and near the Nili Fossae. Prior investigations in this region by the Observatoire pour l'Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) instrument on Mars Express revealed large exposures of both mafic minerals and

Bethany L. Ehlmann; John F. Mustard; Gregg A. Swayze; Roger N. Clark; Janice L. Bishop; Francois Poulet; David J. Des Marais; Leah H. Roach; Ralph E. Milliken; James J. Wray; Olivier Barnouin-Jha; Scott L. Murchie



Geologic Explorations  

NSDL National Science Digital Library

Geologic Explorations allows learners to explore a variety of unique geological formations of Utah using Quicktime Virtual Reality (QTVR) panoramas and digital still imagery. Spectacular panoramas and striking images capture Utah's unique geology and invite students to explore and learn interesting facts and concepts central to the study of geology.

Alec Bodzin



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.




E-print Network

YOUNG GEOLOGY UNIVERSITY May, 1962 GEOLOGY OF THE SOUTHERN WASATCH MOUNTAINS AND VICIN~IM,UTAH C O ....................J. Keith Rigby 80 Economic Geology of North-Central Utah ...,............... Kcnneth C.Bdodc 85 Rod Log ........................Lehi F. Hintze, J. Ka# Ri&, & ClydeT. Hardy 95 Geologic Map of Southern

Seamons, Kent E.


Alteration of ocean crust provides a strong temperature dependent feedback on the geological carbon cycle and is a primary driver of the Sr-isotopic composition of seawater  

NASA Astrophysics Data System (ADS)

On geological timescales there is a temperature dependent feedback that means that increased degassing of CO2 into the atmosphere leads to increased CO2 drawdown into rocks stabilizing Earth's climate. It is widely considered that this thermostat largely comes from continental chemical weathering. An alternative, or additional, feedback comes from dissolution of seafloor basalt in low-temperature (tens of °C), off-axis, hydrothermal systems. Carbonate minerals precipitated in these systems provide strong evidence that increased bottom water temperature (traced by their O-isotopic compositions) leads to increased basalt dissolution (traced by their Sr-isotopic compositions). Inversion of a simple probabilistic model of fluid-rock interaction allows us to determine the apparent activation energy of rock dissolution in these systems. The high value we find (92 ± 7 kJmol-1) indicates a strong temperature dependence of rock dissolution. Because deep-ocean temperature is sensitive to global climate, and the fluid temperature in the upper oceanic crust is strongly influenced by bottom water temperature, increased global temperature must lead to increased basalt dissolution. In turn, through the generation of alkalinity by rock dissolution, this leads to a negative feedback on planetary warming; i.e. off-axis, hydrothermal systems play an important role in the planetary thermostat. Changes in the extent of rock dissolution, due to changes in bottom water temperature, also lead to changes in the flux of unradiogenic Sr into the ocean. The decreased flux of unradiogenic Sr into the ocean due to the cooling of ocean bottom water over the last 35 Myr is sufficient to explain most of the increase in seawater 87Sr/86Sr over this time.

Coogan, Laurence A.; Dosso, Stan E.



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.

Marli Bryant Miller


Structural Geology  

NSDL National Science Digital Library

Created by the University of Nebraska-Lincoln, this site describes the basics of structural geology with text and images. The page includes the discussion of stress, strain, strike and dip, faults, folds, mountain building, erosion, economic geology, and environmental geology. This is a nice introduction to the basic topics in geology. Images from the field help to enhance the topics on the site. Instructors can use this resource to help create or simply enhance their curriculum.


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.


Geological cycles  

Microsoft Academic Search

During the last hundred years, intensive studies have been made on the geological indications of the so called “Ice Ages”;. Already Penck and Bruckner discovered, around the end of the nineteenth century, the cyclic character of these phenomena and distinguished at least four cycles in the Alps area. In fact these geological cycles are controlled by climatic conditions. The geological

B. P. Hageman



Structural Geology  

NSDL National Science Digital Library

This site contains a variety of resources for faculty members who teach undergraduate structural geology. You will find links to activities and assignments, internet and computer resources, useful articles and maps, presentations from the summer 2004 workshop on teaching structural geology, working groups and a discussion forum, and lots of creative ideas for teaching structural geology.


Hometown Geology  

NSDL National Science Digital Library

Students are introduced to concepts in the course that give them the skills to understand geologic maps. These include structural geology, weathering processes, the geologic time scale, types of rocks and minerals, glacial geology, etc. They also look at several quadrangle maps as lab activities, including the Williamsville Quadrangle from Virginia and the Bright Angel Quadrangle from the Grand Canyon. This independent exercise allows students to further investigate their hometown or other areas of interest, and report on the geologic history. This further prepares them for more advanced courses and also gives them an appreciation of their surroundings, a key part of a geologist's training.

Stacey Cochiara


Magnetic properties related to hydrothermal alteration processes at the Escondida porphyry copper deposit, northern Chile  

NASA Astrophysics Data System (ADS)

Fluid-rock interaction related to the circulation of hydrothermal fluids can strongly modify the physicochemical properties of wall rocks in porphyry Cu deposits. These processes can also produce compositional and textural changes in ferromagnetic minerals, which can be quantified using magnetic methods. In the Escondida porphyry Cu deposit of northern Chile, each hydrothermally altered lithology is characterized by a discrete assemblage of Fe-Ti oxide minerals. These minerals have distinctive bulk magnetic susceptibility ( K bulk), temperature-dependent magnetic susceptibility, and magnetic hysteresis parameters. Selectively altered rocks (i.e., potassic and chloritic alteration types) exhibit the highest K bulk values (>3.93 × 10-3 SI units), and their hysteresis parameters indicate multidomain magnetic mineral behavior. This suggests that these rocks are composed of the coarsest magnetic grain sizes within the deposit. Optical analyses and susceptibility-temperature curves confirm that the magnetic signals in selectively altered rocks are mainly carried by secondary magnetite. In contrast, pervasively altered rocks (i.e., quartz-sericite and argillic alteration types) exhibit low K bulk values (<1.93 × 10-4 SI units) and contain smaller pseudo-single domain magnetic grain assemblages. This is consistent with the destruction and/or reduction in size of magnetite under acidic conditions. The results therefore demonstrate a genetic relationship between the hydrothermal alteration processes, Fe-Ti oxide minerals, and magnetic properties of the wall rock in the Escondida deposit. These magnetic methods can be considered a sensitive and efficient petrophysical tool for the identification and semi-quantification of alteration assemblages, and facilitating the recognition and mapping of discrete hydrothermal zones during exploration and operation of porphyry Cu deposits.

Riveros, K.; Veloso, E.; Campos, E.; Menzies, A.; Véliz, W.



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



Utah Geology  

NSDL National Science Digital Library

Utah Geological Survey's Web site, Utah Geology, offers a variety of interesting geological information about the state. Good descriptions, illustrations, and photographs can be accessed on earthquakes and hazards, dinosaurs and fossils, rocks and minerals, oil and energy, and more. For example, the Rocks and Minerals page contains everything from how to stake a mining claim to downloadable summaries of mineral activity in the state. There is quite a bit of information within the site, and anyone interested in geology will find themselves exploring these pages for quite a while.


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.



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.


North Cascades Geology: Geologic Time  

NSDL National Science Digital Library

This article describes the period of geologic time spanned by the rocks of the North Cascades area of Washington. Users can access a simplified geologic time scale that provides links to geologic events in the North Cascades region. These include the deposition of various terranes, periods of intrusion and metamorphism, the beginning of the Cascade volcanic arc, and periods of major glaciation. Links to related materials are also provided.


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.

Yellowstone National Park


Physical geology  

SciTech Connect

The book integrates current thinking on processes (plate techtonics, chemical cycles, changes throughout geologic time). It is an introduction to investigations into the way the earth works, how mountains are formed, how the atmosphere, hydrosphere, crust and mantle interact with each other. Treatments on climate, paleoclimatology and landscape evolution are included, as is a discussion on how human activity affects geological interactions.

Skinner, B.; Porter, S.



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


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.



Geology Major  

E-print Network

Geology Major 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


Exploring Geology  

NASA Astrophysics Data System (ADS)

I am willing to bet a nice bottle of chardonnay that much of the Eos readership has lugged around, fondled, and fumbled through an introductory physical geology textbook of some form or another, once upon a time. Mine, in 1970, was Physical Geology, by Longwell, Flint, and Sanders, which I still have, by the way. Most of us know how ``classical'' physical geology textbooks have been organized: first, a broad overview of Earth processes, then several sections devoted to groups of more specific subjects (e.g., mineralogy, sedimentary rocks, and environments, with one chapter per subject), then several sections devoted to a synthesis of geologic processes in the context of plate tectonics, and finally, typically, a discussion of Earth resources and environment- related issues. Some relatively new textbooks have ventured into new pedagogical formats, for example, emphasizing how we know what we know (e.g., How Does Earth Work: Physical Geology and the Process of Science by Smith and Pun).

Geissman, John W.



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



Infrared spectral identification of metasomatic alteration minerals and its implication to gold exploration in Shihu Gold Deposit, Hebei Province, P.R. China  

NASA Astrophysics Data System (ADS)

Hydrothermal alteration is of great importance for mineral exploration, especially the blind ore-hunting due to its larger scale and special zonation compared to the ore bodies. Infrared spectral identification of metasomatic alteration minerals can be done with little or no sample preparation and quantitative result can be obtained. In this paper, 65 wall-rock samples of several horizontal and vertical profiles were selected from Shihu Gold deposit in Hebei Province to do reflectance spectrum measurements by means of rough surface, smooth section and powder with portable ASD FieldSpec®3 spectrometer. ViewspecPro software was used to preprocess the spectrum, and metasomatic alteration minerals were spectrally discriminated by SII (Spectral International Inc) Specmin software package with wavelength of 1100~2500nm. The results shows that: (1) among all the three spectral libraries embedded in SPECMIN software, i.e., ASD, USGS and JPL, ASD spectral library is more suitable for the spectral hydrothermal alteration minerals identification in Shihu Gold Deposit; (2) the observed mineral zonation from wall-rock gneiss to ore-body indicates obvious downtrend of amphibole, chlorite, sericite, carbonate and barite, which is consistent with the microscopic and XRD results; (3) spectral identification of metasomatic alteration minerals is theoretically feasible, which is economic and convenient, and most important of all, the result can be quantitative or semi-quantitative. The results are helpful and successfully applied to the further mineral exploration in Shihu Gold Deposit.

Liu, Jiacheng; Yao, Yuzeng; Wang, Yingpeng; Yuan, Zhou



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


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.

William L. Newman



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!



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



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))



Geology, geochemistry, and genesis of the Greens Creek massive sulfide deposit, Admiralty Island, southeastern Alaska  

USGS Publications Warehouse

In 1996, a memorandum of understanding was signed by representatives of the U.S. Geological Survey and Kennecott Greens Creek Mining Company to initiate a cooperative applied research project focused on the Greens Creek massive sulfide deposit in southeastern Alaska. The goals of the project were consistent with the mandate of the U.S. Geological Survey Mineral Resources Program to maintain a leading role in national mineral deposits research and with the need of Kennecott Greens Creek Mining Company to further development of the Greens Creek deposit and similar deposits in Alaska and elsewhere. The memorandum enumerated four main research priorities: (1) characterization of protoliths for the wall rocks, and elucidation of their alteration histories, (2) determination of the ore mineralogy and paragenesis, including metal residences and metal zonation within the deposit, (3) determination of the ages of events important to ore formation using both geochronology and paleontology, and (4) development of computer models that would allow the deposit and its host rocks to be examined in detail in three dimensions. The work was carried out by numerous scientists of diverse expertise over a period of several years. The written results, which are contained in this Professional Paper, are presented by 21 authors: 13 from the U.S. Geological Survey, 4 from Kennecott Greens Creek Mining Company, 2 from academia, and 2 from consultants. The Greens Creek deposit (global resource of 24.2 million tons at an average grade of 13.9 percent zinc, 5.1 percent lead, 0.15 troy ounce per ton gold, and 19.2 troy ounces per ton silver at zero cutoff) formed in latest Triassic time during a brief period of rifting of the Alexander terrane. The deposit exhibits a range of syngenetic, diagenetic, and epigenetic features that are typical of volcanogenic (VMS), sedimentary exhalative (SEDEX), and Mississippi Valley-type (MVT) genetic models. In the earliest stages of rifting, formation of precious-metal-rich silica-barite-carbonate white ores began at low temperature in a shallow, subaqueous setting, probably a thin carbonate shelf on the flanks of the Alexander landmass. Epigenetic carbonate replacement textures in the footwall dolostones are overlain by stratiform silica-carbonate-barite-rich ores and indicate that early mineralization formed at and just beneath the paleo sea floor by mixing of a reduced, precious-metal-rich, base-metal-poor hydrothermal fluid with oxygenated seawater. As rifting intensified, the shelf was downfaulted and isolated as a graben. Isolation of the basin and onset of starved-basin shale sedimentation was concurrent with emplacement of mafic-ultramafic intrusives at shallow levels in the rift, resulting in an increasingly higher temperature and progressively more anoxic ore-forming environment. The formation of the main stage of massive sulfide ores began as the supply of bacterially reduced sulfur increased in the accumulating shales. As the main-stage mineralization intensified, shale sedimentation inundated the hydrothermal system, eventually forming a cap. Biogenic sulfate reduction supplied reduced sulfur to the base of the shales where mixing occurred with hot, base-metal-rich hydrothermal fluids. Ore deposition continued by destruction and epigenetic replacement of the early white ores in proximal areas and by inflation and diagenetic replacement of unlithified shale at the interface between the white ores and the base of the shale cap. Ore deposition waned as the shales became lithified and as the supply of bacterially reduced sulfur to the site of ore deposition ceased. The final stages of rifting resulted in the emplacement of mafic-ultramafic intrusive rocks into the Greens Creek system and extrusion of voluminous basaltic flows at the top of the Triassic section. Greenschist facies metamorphism during the Jurassic-Cretaceous accretion of the Alexander terrane to the continental margin resulted in recrystalli

Taylor, Cliff D.; Johnson, Craig A.



Solute transport in crystalline rocks at Äspö — I: Geological basis and model calibration  

NASA Astrophysics Data System (ADS)

Water-conducting faults and fractures were studied in the granite-hosted Äspö Hard Rock Laboratory (SE Sweden). On a scale of decametres and larger, steeply dipping faults dominate and contain a variety of different fault rocks (mylonites, cataclasites, fault gouges). On a smaller scale, somewhat less regular fracture patterns were found. Conceptual models of the fault and fracture geometries and of the properties of rock types adjacent to fractures were derived and used as input for the modelling of in situ dipole tracer tests that were conducted in the framework of the Tracer Retention Understanding Experiment (TRUE-1) on a scale of metres. After the identification of all relevant transport and retardation processes, blind predictions of the breakthroughs of conservative to moderately sorbing tracers were calculated and then compared with the experimental data. This paper provides the geological basis and model calibration, while the predictive and inverse modelling work is the topic of the companion paper [J. Contam. Hydrol. 61 (2003) 175]. The TRUE-1 experimental volume is highly fractured and contains the same types of fault rocks and alterations as on the decametric scale. The experimental flow field was modelled on the basis of a 2D-streamtube formalism with an underlying homogeneous and isotropic transmissivity field. Tracer transport was modelled using the dual porosity medium approach, which is linked to the flow model by the flow porosity. Given the substantial pumping rates in the extraction borehole, the transport domain has a maximum width of a few centimetres only. It is concluded that both the uncertainty with regard to the length of individual fractures and the detailed geometry of the network along the flowpath between injection and extraction boreholes are not critical because flow is largely one-dimensional, whether through a single fracture or a network. Process identification and model calibration were based on a single uranine breakthrough (test PDT3), which clearly showed that matrix diffusion had to be included in the model even over the short experimental time scales, evidenced by a characteristic shape of the trailing edge of the breakthrough curve. Using the geological information and therefore considering limited matrix diffusion into a thin fault gouge horizon resulted in a good fit to the experiment. On the other hand, fresh granite was found not to interact noticeably with the tracers over the time scales of the experiments. While fracture-filling gouge materials are very efficient in retarding tracers over short periods of time (hours-days), their volume is very small and, with time progressing, retardation will be dominated by altered wall rock and, finally, by fresh granite. In such rocks, both porosity (and therefore the effective diffusion coefficient) and sorption Kds are more than one order of magnitude smaller compared to fault gouge, thus indicating that long-term retardation is expected to occur but to be less pronounced.

Mazurek, Martin; Jakob, Andreas; Bossart, Paul



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.


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.


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



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.

Timothy Heaton


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.


Geology Fulbrights  

NASA Astrophysics Data System (ADS)

Fulbright grants in geology for 1988-89 remain open. Specific opportunities are available in Egypt, German Democratic Republic, Hungary, Iceland, Iraq, Kuwait, Morocco, Mozambique, Oman, Poland, Sudan, Syria, Tanzania, Turkey, U.S.S.R., West Bank, Yemen, and Zimbabwe. Other countries are also open to applications in any discipline, and geology is among their preferred fields.The grants are available until awarded and are open only to U.S. citizens. In Central and South America and French-speaking Africa, knowledge of host-country language is required. For more information, contact the Council for International Exchange of Scholars (CIES), 11 Dupont Circle N.W., Suite 300, Washington, DC 20036; tel. 202-939-5401.


Teaching Geology  

NSDL National Science Digital Library

The study of geology at the University of Colorado has a long and distinguished history, and in recent years they have also become increasingly interested in providing online teaching resources in the field. Educators will be glad to learn about this site's existence, as they can scroll through a list of interactive demonstrations that can be utilized in the classroom. Specifically, these demonstrations include a shaded interactive topographical map of the western United States, a magnetic field of the Earth, and several animated maps of various National Park sites. The site comes to a compelling conclusion with the inclusion of the geology department's slide library, which can be used without a password or registration.


Experimental hydrothermal alteration of feldspar: the influence of solid composition on alteration  

E-print Network

EXPERIMENTAL HYDROTHERMAL ALTERATION OF FELDSPAR: THE INFLUENCE OF SOLID COMPOSITION ON ALTERATION A Thesis by MICHAEL JOSEPH PAOLINI Submitted to the Graduate College of Texas A&M University in partial fulfillment of the reguirements... for the degree of MASTER OF SCIENCE December 1985 Major Subject: Geology EXPERIMENTAL HYDROTHERMAL ALTERATION OF FELDSPAR: THE INFLUENCE OF SOLID COMPOSITION ON ALTERATION A Thesis by MICHAEL JOSEPH PAOLINZ Approved as to style and content by: Andre Ha...

Paolini, Michael Joseph



Tour of Park Geology: Shoreline Geology  

NSDL National Science Digital Library

This National Park Service (NPS) site provides links to shoreline geology fieldnotes for National Parks, Monuments, and Recreation Areas. When appropriate, fieldnotes include visitor information, geology, maps, photographs, multimedia resources, geologic research, and teacher features (lessons for teaching geology with National Park examples). Some of the parks included on this site: Acadia National Park, Everglades National Park, and Padre Island National Seashore.


Geologic nozzles  

NASA Astrophysics Data System (ADS)

Sonic velocities of geologic fluids, such as volcanic magmas and geothermal fluids, can be as low as 1 m/s. Critical velocities in large rivers can be of the order of 1-10 m/s. Because velocities of fluids moving in these settings can exceed these characteristic velocities, sonic and supersonic gas flow and critical and supercritical shallow-water flow can occur. 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, supercritical flow occurs where debris discharged from tributary canyons constricts the channel into the shape of a converging-diverging nozzle. The geometry of the channel in these regions can be used to interpret the flood history of the Colorado River over the past 103-105 years. The unity of fluid mechanics in these three natural phenomena is provided by the well-known analogy between gas flow and shallow-water flow in converging-diverging nozzles.

Kieffer, Susan Werner


Geologic Nozzles  

NASA Astrophysics Data System (ADS)

Sonic velocities of geologic fluids, such as volcanic magmas and geothermal fluids, can be as low as 1 m/s. Critical velocities in large rivers can be of the order of 1-10 m/s. Because velocities of fluids moving in these settings can exceed these characteristic velocities, sonic and supersonic gas flow and critical and supercritical shallow-water flow can occur. 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 gyeser 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 debris flows that enter from tributary canyons. Both subcritical and supercritical flow occur within the rapids. The transport capacity in the rapids can be so great that the river contours the channel to a characteristic shape. This shape can be used to interpret the flood history of the Colorado River over the past 10³-105 years. The unity of fluid mechanics in these three natural phenomena is provided by the well-known analogy between gas flow and shallow-water flow in converging-diverging nozzles.

Kieffer, Susan Werner



A Handbook for Geology Students Why study Geology?.............................................................................................3  

E-print Network

1 A Handbook for Geology Students #12;2 Contents Why study Geology ..................................................................................7 Why Appalachian Geology?................................................................................10 Geology Faculty and Staff

Thaxton, Christopher S.


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.



Illinois State Geological Survey  

NSDL National Science Digital Library

The Illinois State Geological Survey (ISGS) homepage provides information on geologic mapping, earthquakes, fossils, groundwater, wetlands, glacial geology, bedrock geology, and Lake Michigan geology. Educational materials include field trip guides, short publications on Illinois geology for students and teachers, online tours, single-page maps, and a geologic column. Other materials include databases and collections of GIS data, well records, drill cores, and mining information; a bibliography of Illinois geology; online maps and data; and information on water and land use, resource development, and geologic hazards.


Geology of Kilauea volcano  

SciTech Connect

This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower east rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. 71 refs., 2 figs.

Moore, R.B. (Geological Survey, Denver, CO (United States). Federal Center); Trusdell, F.A. (Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory)



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.



Geological Time Scale  

NSDL National Science Digital Library

This document describes how geologic time is approached in discussions of geologic topics. The uses of relative time and absolute time are compared, and a geologic time scale is provided to represent both concepts. References are provided.


West's Geology Resources  

NSDL National Science Digital Library

This is one of the world's largest geological web sites, with more than 200 web pages comprised of geological field guides, with hundreds of full screen color photographs of varied geological features, and with associated bibliographies. All of the field guides are for geologic locations in England. Also included is a large directory of internet sites sorted by topic. Topics range from mineral and rock types, to geologic time periods, fossils, plate tectonics, geochronology, mapping, and geologic surveys.

Ian West


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)



Old Geology and New Geology  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 28 May 2003

Mangala Vallis one of the large outflow channels that channeled large quantities of water into the northern lowlands, long ago on geological timescales. This valley is one of the few in the southern hemisphere, as well as one of the few west of the Tharsis bulge. A closer look at the channel shows more recent weathering of the old water channel: the walls of the channel show small, dark slope streaks that form in dusty areas; and much of the surrounding terrain has subtle linear markings trending from the upper left to the lower right, which are probably features sculpted and streamlined by the wind. Geology still shapes the surface of Mars today, but its methods over the eons have changed.

Image information: VIS instrument. Latitude -6, Longitude 209.6 East (150.4 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.



Co2 geological sequestration  

SciTech Connect

Human activities are increasingly altering the Earth's climate. A particular concern is that atmospheric concentrations of carbon dioxide (CO{sub 2}) may be rising fast because of increased industrialization. CO{sub 2} is a so-called ''greenhouse gas'' that traps infrared radiation and may contribute to global warming. Scientists project that greenhouse gases such as CO{sub 2} will make the arctic warmer, which would melt glaciers and raise sea levels. Evidence suggests that climate change may already have begun to affect ecosystems and wildlife around the world. Some animal species are moving from one habitat to another to adapt to warmer temperatures. Future warming is likely to exceed the ability of many species to migrate or adjust. Human production of CO{sub 2} from fossil fuels (such as at coal-fired power plants) is not likely to slow down soon. It is urgent to find somewhere besides the atmosphere to put these increased levels of CO{sub 2}. Sequestration in the ocean and in soils and forests are possibilities, but another option, sequestration in geological formations, may also be an important solution. Such formations could include depleted oil and gas reservoirs, unmineable coal seams, and deep saline aquifers. In many cases, injection of CO2 into a geological formation can enhance the recovery of hydrocarbons, providing value-added byproducts that can offset the cost of CO{sub 2} capture and sequestration. Before CO{sub 2} gas can be sequestered from power plants and other point sources, it must be captured. CO{sub 2} is also routinely separated and captured as a by-product from industrial processes such as synthetic ammonia production, H{sub 2} production, and limestone calcination. Then CO{sub 2} must be compressed into liquid form and transported to the geological sequestration site. Many power plants and other large emitters of CO{sub 2} are located near geological formations that are amenable to CO{sub 2} sequestration.

Xu, Tianfu



Colorado Geological Survey  

NSDL National Science Digital Library

The Colorado Geological Survey (CGS) is an agency of state government within the Department of Natural Resources whose mission is to help reduce the impact of geologic hazards on the citizens of Colorado, to promote the responsible economic development of mineral and mineral fuel resources, to provide geologic insight into water resources, and to provide geologic advice and information to a variety of constituencies. This site contains extensive information about Colorado geology such as maps, a geologic time scale for the state, program information, and state field trip information. This site hosts the Avalanche Information Center which contains avalanche forecasting and education center details. Publications report on geologic hazards, land use, environmental geology, mineral resources, oil, gas, coal, geologic mapping and earthquake information for the state. There are online editions of RockTalk, which is a quarterly newsletter published by the Colorado Geological Survey dealing with all aspects of geology throughout the state of Colorado. Links are provided for more resources.



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



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


Maryland Geological Survey  

NSDL National Science Digital Library

The Maryland Geological Survey (MGS) homepage contains information from MGS programs on hydrogeology, hydrology, coastal and estuarine geology, environmental geology and mineral resources; an online guide to Maryland geology; and information on oyster habitat restoration projects. There are also maps, data, information on MGS publications, MGS news, and online educational resources.


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.



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


Geologic Maps and Mapping  

NSDL National Science Digital Library

This portal provides access to resources on geologic mapping, and to sources of geologic maps. There is an introduction to geologic mapping, which summarizes its principles and practices, and a history of United States Geological Survey (USGS) mapping activities from 1879 to the present, as well as links to papers on the values and hazards associated with geologic maps and mapping. Online sources of maps include the USGS Geologic Map Database, other federal map products (FEDMAP), state geological survey products (STATEMAP), and university map products (EDMAP).


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.



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 ...


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.


Geological Sciences 330 Fall 2007 Sedimentary Geology  

E-print Network

: Sediments and Sedimentary Rocks Week 3 17 Sept Sedimentary Textures and Rock Classification 19 Sept Fluid Dynamics (2 & 3) Lab 2: Sedimentary Rock Classification Week 4 24 Sept Sediment Entrainment and DepositionGeological Sciences 330 Fall 2007 Sedimentary Geology This course is intended to provide


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.



Louisiana Geological Survey  

NSDL National Science Digital Library

The Louisiana Geological Survey, located at Louisiana State University, developed this website to promote its goal to provide geological and environmental data that will allow for environmentally sound natural resource development and economic decisions. Users can find general information about the Survey's mission, staff, plan, and history. The website features the research and publications of the Basin Research, Cartographic, Coastal, Geologic Mapping, and Water and Environmental sections. Researchers can discover stratigraphic charts of Louisiana, information on lignite resources, and other geologic data.


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.


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



Teaching Sedimentary Geology  

NSDL National Science Digital Library

This site contains a variety of resources for faculty members who teach undergraduate sedimentary geology. You will find links to a growing collection of activities and assignments, internet and computer resources, useful articles, presentations from the summer 2006 workshop on teaching sedimentary geology, and lots of creative ideas for teaching sedimentary geology.


Environmental geology in Australia  

Microsoft Academic Search

In Australia the concept of environmental geology is developing slowly from mainly engineering based activities to resource planning and utilization. This is particularly so with increasing activity in urban geology and in some States environmental geology influences land use and zoning. Since 1972 there have been clearly stated national policies in regard to the planned development of Australia's mineral and

G. M. Philip



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.


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


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



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




NSDL National Science Digital Library

At, 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.


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.


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.


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.


Petrologic characteristic and Geological Model of Igneous Reservoir: An example in Zhanhua Seg, Eastern China  

NASA Astrophysics Data System (ADS)

The diabase is a typical igneous rock, which intrude the oil-bearing mudstone and form potential reservoir. As an example of Luo151 igneous rock in Zhanhua Seg, Eastern China, we studied the diabase reservoir in detail, including petrologic analysis, reservoir anisotropy and geological modeling. Four lithofacies zones are divided according to analyzing petrology, texture and structureϻwhich comprise carbonaceous slate, hornfels containing cordierite and grammite, border subfacies and central subfacies, and the petrologic types include carbonaceous slate, hornfels, and diabases. The diabase construction is divided into grammite hornfels micropore and diabase porous-fracture type reservoirs. The mudstone layers in Third Member of Shahejie Formation (Es3) provide favorable hydrocarbon source rock and cap formation, diabase and hornfels belts serve as reservoirs, faults and microcracks in the wall rocks as the pathways for oil and gas migration. The invasive time was about in the later deposition period of Dongying Formation and the middle of that of Guantao Formation, the oil generated from oil source rock of Es3 in the period of the Minghuazhen formation and is earlier more than the period of diabase oil trap and porous space forming.

Li, Q.; Shao, S.; Kang, R.; Liu, K.



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.



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.


Louisiana Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Louisiana Geological Survey (LGS). The site includes general information about LGS and its various offices, as well as an overview of the Basin Research Energy Section, the oil, gas, and coal research section of LGS. The publications and data page features a catalog and ordering information for documents on mineral resources, fossils, water resources, geological bulletins and maps, and many others, as well as a selection of downloadable maps, including 30 x 60 minute geologic quadrangles, a generalized geologic map of the state with accompanying text, and an online map viewer of the state with selectable layers (geology, water bodies, cultural features, and Landsat imagery). There is also an online listing of well logs, grouped by parish, online listings of core samples, grouped by state, and downloadable public information documents on a variety of geologic topics.


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.



The Geology of Virginia  

NSDL National Science Digital Library

From the College of William of Mary Department of Geology comes the Geology of Virginia Web site. From the Appalachian Plateau to the coastal plain, visitors can explore the geology and physical characteristics of the diverse landscape of the commonwealth of Virginia through simple descriptions and well designed graphics. Even if you don't live in the area, the site does a good job of capturing the interest of anyone looking for quality material on the presented subjects.


North Carolina Geological Survey  

NSDL National Science Digital Library

The North Carolina Geological Survey (NCGS) examines, describes, and maps the state's geology and mineral resources and publishes reports and maps. The site contains lists of publications, maps, aerial photographs, frequently asked questions about North Carolina geology, and mineral and professional information. Project Earth Science is designed to provide relevant and accurate earth science education information for the state's high school students and earth/environmental science teachers.


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.


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.


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


Environmental Geology Major  

E-print Network

Environmental Geology Major 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


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.


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



Structural Geology 'Research' Conference  

NSDL National Science Digital Library

In this assignment students read and discuss a peer-reviewed journal article and prepare for and attend our class 'research' conference. In the conference they present on an area of current research as discussed in the journal article they read, and they practice formulating questions about other's research. Outcomes: 1. Read and discuss a structural geology peer-reviewed journal article. 2. Prepare a presentation that demonstrates your understanding of a current research topic in structural geology. 3. View and understand several diverse areas within geology and geophysics that use structural geology in research. 4. Ask questions relevant to a research presentation.

Julie Willis


Understanding Geologic Maps  

NSDL National Science Digital Library

This is an exercise in which students are reintroduced to geologic maps and encouraged to "deconstruct" the map into constituent elements in order to understand the geologic history of the area. The preceding lectures in the course have recapitulated material that the students have covered in Introduction to Physical Geology. During class, the students work through the maps that were part of lab exercises in the Intro level course, so that basic concepts are recalled (superposition, cross-cutting relationships, basic faults and folds). The final product is a geologic history of this map area.

Cara Burberry


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


Hydrothermal alteration associated with rift zones at Fangataufa atoll (French Polynesia)  

NASA Astrophysics Data System (ADS)

The Mururoa and Fangataufa atoll basement consists of superimposed submarine and subaerial lava flows which have been intruded by late volcanics. The intrusions have developed large hydrothermal alteration haloes throughout the basaltic wall rock. The cuttings of the Natice-1 and Mitre-1 holes, drilled into the submarine volcanic pile at Fangataufa atoll, show a vertical zonation of clay minerals ranging from 270 to 850m depth. The newly formed clay minerals occurring from top to bottom of the altered pile are: dioctahedral aluminous smectites, saponite, an intimate assemblage of saponite with two random chlorite/saponite mixed layers and an intimate assemblage of one random chlorite/saponite mixed-layer with one ordered chlorite/saponite mixed layer and one chlorite below 816m depth. These clay mineral assemblages indicate a general increase in the chloritic component with depth. They are associated throughout the pile with secondary carbonates and quartz. The ?18O and ?13C of calcite and ?18O of clay minerals, on the one hand, and the intimate mixtures of trioctahedral species, on the other, suggest a general cooling with the evolution of a paleogeothermal gradient from approximately 300 °C/km during the crystallization of chlorite to 150 °C/km for the late calcite precipitation.

Dudoignon, P.; Proust, D.; Gachon, A.


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

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



Structural Geology Techniques  

NSDL National Science Digital Library

The University of Wisconsin - Green Bay has created this collection of material and instructions on how to analyze and plot structural geology data. Topics covered includes planes, lines, relations between lines and planes, geologic structures, intersection of structures with topography, stereonet techniques, stress and strain, and analysis of complex structures.

Dutch, Steven


Advances in planetary geology  

NASA Technical Reports Server (NTRS)

This second issue in a new series intended to serve the planetary geology community with a form for quick and thorough communications includes (1) a catalog of terrestrial craterform structures for northern Europe; (2) abstracts of results of the Planetary Geology Program, and (3) a list of the photographic holdings of regional planetary image facilities.

Woronow, A. (editor)



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)



National Geologic Map Database  

NSDL National Science Digital Library

The National Geologic Map Database (NGMDB) is an Internet-based system for query and retrieval of earth-science map information, created as a collaborative effort between the USGS and the Association of American State Geologists. Its functions include providing a catalog of available map information; a data repository; and a source for general information on the nature and intended uses of the various types of earth-science information. The map catalog is a comprehensive, searchable catalog of all geoscience maps of the United States, in paper or digital format. It includes maps published in geological survey formal series and open-file series, maps in books, theses and dissertations, maps published by park associations, scientific societies, and other agencies, as well as publications that do not contain a map but instead provide a geological description of an area (for example, a state park). The geologic-names lexicon (GEOLEX) is a search tool for lithologic and geochronologic unit names. It now contains roughly 90% of the geologic names found in the most recent listing of USGS-approved geologic names. Current mapping activities at 1:24,000- and 1:100,000-scale are listed in the Geologic Mapping in Progress Database. Information on how to find topographic maps and list of geology-related links is also available.



External Resource: Geologic Time  

NSDL National Science Digital Library

This NASA sponsored webpage, Center for Educational Technologies, teaches students about Geologic Time. The age of Earth is so long compared to all periods of time that we humans are familiar with, it has been given a special name: Geologic time. The age



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.



Marine Geological Discoveries  

NSDL National Science Digital Library

This site by a Norwegian researcher features descriptions of marine geological formations: pockmarks, mud volcanoes, deep-water coral reefs, and gas hydrates. Using ROV technology, he has taken photos of these deep seafloor features, and compares them to geological structures seen on land, and even on the moon.


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.

California Geological Survey


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



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.



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.


Earthquakes and Geology  

NSDL National Science Digital Library

In this activity, students investigate the relationship between intensity of ground motion and type of rock or alluvium, as seen in the 1994 Northridge, California earthquake. They will examine a map of Mercalli intensity, a cross-section showing geologic structures and rock types, and a map of surficial geology, and answer questions pertaining to amplification of ground motion and S-wave velocities.

David Ozsvath


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.

John Wagner


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



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.


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



Virtual Tour of Maine Geology  

NSDL National Science Digital Library

This selection of slide shows provides a photographic tour of Maine geology. Users can choose slide shows on surficial, bedrock, and coastal geology; fossils, geologic hazards, groundwater and wells; or mineral collecting, mining, and quarrying.


GEOLOGY | April 2013 | 395 INTRODUCTION  

E-print Network

.3 � 105 kg of magma and wall-rock lithic clasts were erupted. Following the eruption, 100 juvenile pyroclasts were collected for analysis. From macroscopic clast observations and clast density, nine (FTIR) analysis, and X-ray microtomography (µXRT) at the Advanced Light Source, Lawrence Berkeley

Gonnermann, Helge


GEOLOGY | April 2013 | 395 INTRODUCTION  

E-print Network

.3 Ã? 105 kg of magma and wall-rock lithic clasts were erupted. Following the eruption, 100 juvenile pyroclasts were collected for analysis. From macroscopic clast observations and clast density, nine (FTIR) analysis, and X-ray microtomography (XRT) at the Advanced Light Source, Lawrence Berkeley

Manga, Michael


Geology of the Mother Load gold belt and adjacent foothills metamorphic belt, California  

SciTech Connect

The late Jurassic Mother Lode gold-quartz vein system south of the Consumnes River is hosted by portions of 1) a submarine volcanic arc and overlying epiclastic basin, and 2) the ultramafic-mafic plutonic subarc basement. During accretion to the Paleozoic shelf of western North America, the subarc basement tectonically intruded the disrupted arc basin, incorporating hanging wall lithologies to produce the tectonic melange of the Melones fault zone (MFZ). Late orogenic dikes intrude the margins of the MFZ and adjacent wall rocks. These dikes were altered during the gold-quartz vein formation. The proximal to medial volcanic strata are, from oldest to youngest: 1) island arc tholeiitic pillow basalts, 2) a thin radiolarian chert bed grading into 3) a submarine volcaniclastic sequence, and 4) sporadically distributed flows of calc-alkaline basalt through boninite. Cessation of volcanic activity is marked by the deposition of an organic carbon-rich epiclastic sequence. The intensely folded strata in JT rocks east of the MFZ may be basinward lateral equivalents of the JT strata west of the MFZ. Differences in style of deformation and metamorphic rank in the strata are typical of vertical and lateral variations in basins where one part is passive and another part is tectonically active as the basin closes.

Landefeld, L.A.



Conference on Early Mars: Geologic and Hydrologic Evolution, Physical and Chemical Environments, and the Implications for Life  

NASA Technical Reports Server (NTRS)

Topics considered include: Geology alteration and life in an extreme environment; developing a chemical code to identify magnetic biominerals; effect of impacts on early Martin geologic evolution; spectroscopic identification of minerals in Hematite-bearing soils and sediments; exopaleontology and the search for a Fossil record on Mars; geochemical evolution of the crust of Mars; geological evolution of the early earth;solar-wind-induced erosion of the Mars atmosphere. Also included geological evolution of the crust of Mars.

Clifford, S. M. (Editor); Treiman, A. H. (Editor); Newsom, H. E. (Editor); Farmer, J. D. (Editor)



Sand Sea Wonders: Geology  

NSDL National Science Digital Library

This site describes the geology of The Great Sand Dunes National Monument and Preserve. Active links allow students to explore the geologic timeline, geologic cross section in animation, and the wind regime. A reversing dune is shown in animation and other dunes such as star, parabolic, barchan, and transverse are discussed. Another section illustrates sand recycling by seasonal streams. A sand deposits map shows topography, dunes watershed, old national monument boundary, roads, and surface water and a section called 'How Much Sand' quantifies the description. Artwork on this site includes both adult and 'Hands on the Land' student artwork while photography depicts dunes, landscape, animals, plants, and human history.


Indiana Geological Survey  

NSDL National Science Digital Library

This is the homepage of the Indiana Geological Survey (IGS). Site materials include information on Earth science issues such as groundwater, mapping, coal and mineral resources, oil and gas, and seismic hazards. There is also information on the geologic time scale and stratigraphic record, rocks and minerals, fossils (including nautiloids of the Ordovician period in Indiana), caves and karst topography in Indiana, and glacial geology. The Geographic Information Ssytems (GIS) and mapping section includes a GIS atlas for the state, an online map viewer, links to the Indiana coal mine information system, petroleum database management system, and a download page where users can access GIS datasets for the state.


Florida Geological Survey  

NSDL National Science Digital Library

The Florida Geological Survey (FGS) homepage provides data, research materials and interpretations on aquifer systems, geologic frameworks, landforms, energy and non-energy mineral resources, and geologic hazards which which can be used to address issues of conservation and protection, sustainable development, human health protection, and implementation of successful environmental regulatory programs. Educational materials for earth science and the pre-historic development of the state are also provided. These include topics such as sinkholes, data and maps, rock and mineral identification, minerals, hydrogeology, and fossils.


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.


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.



Geology by Lightplane  

NSDL National Science Digital Library

This site contains 360 color aerial photographs of geologically significant landscapes in the western United States, as well as in Minnesota, Wisconsin, Iowa, Illinois, Indiana, Michigan and Kentucky. The photos are meant to be useful teaching aides for introductory geology classes to establish the relationship between the overall landscape and ground-based geological features. The photos are reduced to a width of 640 pixels and are arranged geographically. Each picture is accompanied by a caption that provides geographic orientation, location, and the date it was taken. 2000-pixel-wide versions can be downloaded from a linked FTP site.

Louis Maher, Jr.


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



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.


IU GEOLOGICAL SCIENCES graduatehandbookappendices  

E-print Network

jknjau Geol Sci Assoc. Professor Greg Olyphant Hydrogeology, Quaternary Geology and Geomorphology 5. Professor Chen Zhu Hydrogeology, Mass Transport, Water-Rock-Gas-Microbe Interactions 5-8852 MSBII 424 czhu

Polly, David


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.

Jim Miller


Digital Geology of Idaho  

NSDL National Science Digital Library

If you have ever wanted to learn about the geology of Idaho, this site is a great way to explore everything from Coeur d'Alene to the Sawtooth Mountains. This digital version of a course offered at Idaho State University systematically divides Idaho geology into a set of different teaching modules. The modules cover topics like the Idaho Batholith, the Columbia River Basalts, and the Lake Bonneville Flood. Each module contains maps, charts, diagrams, and photographs that illuminate the various geological processes that have formed, and continue to form, in each region of the state. Many of the modules also have fly-throughs that superimpose color-coded geology on 3-D topographic maps to provide a graphic visualization Idaho's rivers. Additionally, the site contains slide shows and a set of teaching exercises.



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.

Environmental Literacy and Inquiry Working Group at Lehigh University


Geology and Human Health  

NSDL National Science Digital Library

The link between geology and human health may not seem obvious, but it many ways geology can affect public health in a variety of crucial ways. Certainly, the relationship between geological factors and water and air quality is one that continues to interest policy makers and others. This site explores these issues, and it was created by the people at Carleton College's Professional Development for Geoscience Faculty initiative. Here visitors can make use of a wide range of educational and supporting materials, including classroom activities, key visualizations, and collections of external links. First-time users may wish to start at the "Resources for Educators" area, which includes a brief overview titled "Essential components of geology and human health" and several helpful posters. The remaining materials can be viewed in sections that include "Bookshelf", "Visualizations", and "Internet Resources".


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.


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.


Devil's Tower Geology  

NSDL National Science Digital Library

This site from the National Park Service briefly addresses the geology of Devil's Tower. The evolution of various theories on the formation of the tower are discussed. A slide show of the emplacement of the tower is also available.

National Park Service (NPS)


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.

Marli Miller


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.


Advances in Planetary Geology  

NASA Technical Reports Server (NTRS)

The surface of Mars displays a broad range of channel and valley features. There is as great a range in morphology as in scale. Some of the features of Martian geography are examined. Geomorphic mapping, crater counts on selected surfaces, and a detailed study of drainage basins are used to trace the geologic evolution of the Margaritifer Sinus Quandrangle. The layered deposits in the Valles Marineris are described in detail and the geologic processes that could have led to their formation are analyzed.

Grant, John A., III; Nedell, Susan S.



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


Manitoba Geological Survey  

NSDL National Science Digital Library

This site offers materials on Manitoba geology and minerals, mining and mineral exploration, a Digital Elevation Model of Southern Manitoba (DEMSM) landforms including oblique views, an interactive GIS map gallery of minerals and geology, a study of paleofloods in the Red River Basin including photographs illustrating how scientists delineated the paleofloods, and information on the Manitoba Protected Areas Initiative. Some maps and reports are available to download.


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


USGS: Geology in the Parks  

NSDL National Science Digital Library

The US Geological Survey Geology in the Parks Web site is a cooperative project of the USGS Western Earth Surface Processes Team and the National Park Service. This extensive site covers geologic maps, plate tectonics, rocks and minerals, geologic time, US geologic provinces, park geology of the Mojave, Sunset Crater, Lake Mead, North Cascades, Death Valley, Yosemite National Park, and much more. Descriptions, graphics, photographs, and animations all contribute to this informative and interesting Web site making it a one stop, all encompassing, resource for everything geology and US national park related.


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.



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.


Pattern Alteration: Special Alterations for Pants  

E-print Network

circumference alterations. Make all crotch depth alterations on front and back pattern pieces. To shorten: 1. Fold the pattern by the amount you need along the lengthening and shortening line designated on the pattern at the hip line. 2. Tape the pattern... the pattern apart at the hip lengthening and shorten- ing line. Figure 1. 2 ................................................................................................................................................................................. 3...



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.



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.



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.


The geology of Ganymede  

NASA Astrophysics Data System (ADS)

A broad outline of the geologic history of Ganymede is presented, obtained from a first attempt to map the geology on a global scale and to interpret the characteristics of the observed geologic units. Features of the ancient cratered terrain such as craters and palimpsests, furrows and troughs, are discussed. The grooved terrain is described, including its sulci and cells, and the age relation of these units is considered along with the structure and origin of this terrain. The Gilgamesh Basin and Western Equatorial Basin in the post grooved terrain are treated, as are the bright and dark ray craters and the regolith. The development of all these regions and features is discussed in context. For the regolith, this includes the effect of water migration, sputtering, and thermal annealing. The histories of the ancient cratered terrain, the grooved terrain, and the post grooved terrain are presented.

Shoemaker, E. M.; Lucchitta, B. K.; Wilhelms, D. E.; Plescia, J. B.; Squyres, S. W.


The geology of Ganymede  

NASA Technical Reports Server (NTRS)

A broad outline of the geologic history of Ganymede is presented, obtained from a first attempt to map the geology on a global scale and to interpret the characteristics of the observed geologic units. Features of the ancient cratered terrain such as craters and palimpsests, furrows and troughs, are discussed. The grooved terrain is described, including its sulci and cells, and the age relation of these units is considered along with the structure and origin of this terrain. The Gilgamesh Basin and Western Equatorial Basin in the post grooved terrain are treated, as are the bright and dark ray craters and the regolith. The development of all these regions and features is discussed in context. For the regolith, this includes the effect of water migration, sputtering, and thermal annealing. The histories of the ancient cratered terrain, the grooved terrain, and the post grooved terrain are presented.

Shoemaker, E. M.; Lucchitta, B. K.; Wilhelms, D. E.; Plescia, J. B.; Squyres, S. W.



Geological fakes and frauds  

NASA Astrophysics Data System (ADS)

Some geological fakes and frauds are carried out solely for financial gain (mining fraud), whereas others maybe have increasing aesthetic appeal (faked fossils) or academic advancement (fabricated data) as their motive. All types of geological fake or fraud can be ingenious and sophisticated, as demonstrated in this article. Fake gems, faked fossils and mining fraud are common examples where monetary profit is to blame: nonetheless these may impact both scientific theory and the reputation of geologists and Earth scientists. The substitution or fabrication of both physical and intellectual data also occurs for no direct financial gain, such as career advancement or establishment of belief (e.g. evolution vs. creationism). Knowledge of such fakes and frauds may assist in spotting undetected geological crimes: application of geoforensic techniques helps the scientific community to detect such activity, which ultimately undermines scientific integrity.

Ruffell, Alastair; Majury, Niall; Brooks, William E.



Geology for Everyone  

NSDL National Science Digital Library

This Geological Survey of Ireland website can increase the public's excitement about geology by offering simple, straightforward materials on the basics of geology. The website is divided into numerous themes such as Volcanoes, Rocks, Caves, and the Water Cycle. The links from each of the headings introduce the topic with simple descriptions and remarkable pictures and offer easy experiments when applicable. Students and educators can take virtual tours of the Ox Mountains, Killiney Beach, and other Irish landscapes. Everyone should visit the Landscapes for the Living link, which offers outstanding images of the diverse landscapes of Europe. While some of the themes are currently under construction, including Planet Earth, Plate Tectonics, and Earthquakes, the authors indicate that these materials will be added in the near future.


Geology By Lightplane  

NSDL National Science Digital Library

In 1966, Professor Louis J. Maher of the University of Wisconsin-Madison's Department of Geology and Geophysics piloted a department-owned Cessna over the continental US taking photos for use in his geology courses. As Maher flew, his trusty co-pilot and graduate assistant, Charles Mansfield, snapped the photos. The resulting collection is an assortment of breathtaking images of classic geological features, now available online for noncommercial use by educators (download via FTP). Maher gives us birds-eye views of structural features in Wyoming's Wind River Range, sedimentary strata in Arches National Park and the Grand Canyon, glacial landscapes in Northern Minnesota, and ancient lava flows in Arizona, to name just a few.

Maher, Louis J.


Roping Geologic Time  

NSDL National Science Digital Library

After having talked about the geologic time scale (Precambrian: prior to 570 Ma; Paleozoic: 570-245 Ma; Mesozoic: 245-65 Ma; Cenozoic: 65 Ma - Present), I ask for two volunteers from the class to hold a rope that is 50 feet long. I say that one end is the beginning of the Earth (4.6 billion years ago), and the other is today. I then give out 16 clothes pins and ask various students to put a cloths pin on the 'time line' at various 'geologic events'. For example, I ask them to put one where the dinosaurs died out (end of the Mesozoic). They almost invariably put it much too old (65 Ma is less than 2% of Earth history!). Then I ask them to put one on their birthday (they now laugh). Then I ask them to put one where we think hominoids (humans) evolved (~3-4 Ma), and they realize that we have not been here very long geologically. Then I ask them to put one at the end of the Precambrian, where life took off in terms of the numbers of species, etc. They are amazed that this only represents less than 15% of Earth history. Throughout the activity I have a quiz going on where the students calculate percentages of Earth History for major geologic events, and compare it to their own ages. On their time scale, the dinosaurs died only about two 'months' ago! The exercise is very effective at letting them get a sense of how long geologic time is, and how 'recently' some major geologic events happened when you consider a time scale that is the age of the earth.

Randall Richardson


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...



Geology and image processing  

NASA Technical Reports Server (NTRS)

Digital image processing for geological applications will be integrated with geographic information systems and data base management systems. While multiband data sets from radar and multispectral scanners will make extreme demands on memory, bus and processor architectures, it is expected that array processors and VLSI/VHSIC dedicated function chips will allow the use of fast Fourier transform and classification algorithms. It is anticipted that, as processor power increases, the weakest link of a processing system will become the analyst who uses it. Human engineering of systems is therefore recommended for the most effective utilization of remotely sensed geologic data.

Daily, M.



Planetary geological processes  

NASA Astrophysics Data System (ADS)

In this introduction to planetary geology, we review the major geologic processes affecting the solid bodies of the solar system, namely volcanism, tectonism, impact cratering, and erosion. We illustrate the interplay of these processes in different worlds, briefly reviewing how they affect the surfaces of the Earth's Moon, Mercury, Venus and Mars, then focusing on two very different worlds: Jupiter's moon Io, the most volcanically active object in the solar system, and Saturn's moon Titan, where the interaction between a dense atmosphere and the surface make for remarkably earth-like landscapes despite the great differences in surface temperature and composition.

Lopes, Rosaly M. C.; Solomonidou, Anezina



Project Earth Science: Geology  

NSDL National Science Digital Library

Now you can literally explain what it's like "between a rock and a hard place!" Use Project Earth Science: Geology to introduce your students to plate tectonics and teach them what causes volcanoes and earthquakes. Lead explorations of these and other larger-than-the-classroom geological phenomena with the teacher-tested, Standards -based activities. Earth's physical evolution and dynamic processes are carefully explained in language accessible to students and teachers. Supplemental readings provide educators with the background information to answer student questions and concerns.

Brent A. Ford



Introduction to Geology  

NSDL National Science Digital Library

If you are having difficulty remembering the details of the Earth's geological structure or the nature of major minerals and rock types, you can consult this excellent introductory course offered as part of MIT's OpenCourseWare initiative. The materials are drawn from Professors Perron and Jagoutz's 2011 "Introduction to Geology" course, and they include a number of lecture notes, available for download in PDF file format. The course is designed for undergraduates, though anyone can benefit from examining the materials. Visitors can make their way through lecture notes that cover metamorphic rocks, rock deformation, earthquakes, and the formation of continents.

Jagoutz, Oliver


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.


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



[Altered states of consciousness].  


The review of modern ideas concerning the altered states of consciousness is presented in this article. Various methods of entry into the altered states of consciousness are looked over. It is shown that the altered states of consciousness are insufficiently known, but important aspects of human being existence. The role of investigation of the altered states of consciousness for the creation of integrative scientific conception base is discussed. PMID:15810684

Gora, E P



Hydrothermal alteration in the Mount Hood Area, Oregon. Bulletin  

Microsoft Academic Search

The report describes the hydrothermal alteration of numerous outcrop samples collected in the vicinity of Mount Hood, as well as drill cuttings from 13 of the geothermal drill holes for which the authors were able to obtain sample splits. The study is also an outgrowth of a geologic and mineral survey of the Mount Hood Wilderness area in compliance with

K. E. Bargar; T. E. C. Keith; M. H. Beeson



Geology: The Active Earth.  

ERIC Educational Resources Information Center

Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Geology: The Active Earth." Contents are organized into the following…

Braus, Judy, Ed.



Java Structural Geology Software  

NSDL National Science Digital Library

This website features Java programs that illustrate basic structural geology concepts. This suite of animations includes topics such as shear, stress versus strain, three dimensional strain, flow lines, rotating clasts and others. The animations are downloadable for Mac, PC and Linux.

Skylar L. Primm


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



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)


Urban Geology (GEOL357)  

NSDL National Science Digital Library

This webpage describes the Urban Geology class at California State University - Los Angeles. The course explores the natural environment in and around urban population centers and looks at how planners can mitigate the effects of natural phenomena such as earthquakes, floods, and landslides.

California State University, L.A. - Geological Sciences


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.


Geologic Structures Lab  

NSDL National Science Digital Library

Students learn about the variables governing the brittle and ductile behavior of rocks, the simple geological structures associated with differential stress, and look at and apply real data to evaluate the depth to the brittle-ductile transition in the crust and how that depth can change temporarily due to sudden changes in stress introduced by large earthquakes.

John Leland


The Geology of Australia  

Microsoft Academic Search

The Geology of Australia provides a vivid and informative account of the evolution of the Australian continent over the past 4400 million years. Starting with the Precambrian rocks which hold clues to the origins of life and the development of an oxygenated atmosphere, it then covers the warms seas, volcanism and multiple orogenies of the Palaeozoic, which built the eastern

David Johnson



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


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 ( and Cathryn Field, Lab Instructor ( Example compiled by Suzanne Savanick, Science Education Resource Center (


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...


Geologic provinces of Oklahoma  

Microsoft Academic Search

The geologic provinces of Oklahoma are mainly the product of tectonics and attendant sedimentation of Pennsylvanian age. Most boundaries are structural; thus, the provinces map is a generalized tectonic map. Permian and post-Paleozoic strata tend to mask those structures, but most of those strata have been removed by erosion, except in the Anadarko Basin and the Wichita Uplift provinces. The

R. A. Northcutt; J. A. Campbell



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.

William Hirt



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: ...


Mass Extinctions Geology 331  

E-print Network

Mass Extinctions Geology 331 Paleontology #12;The Phanerozoic Eons are divided by Mass Extinctions Permian K-T #12;How have physical changes on the earth effected the evolutionary history of life during the Phanerozoic? #12;Types of Extinction · Background Extinction ­ when species go extinct through natural

Kammer, Thomas


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....


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



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...


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.



Geology of the Colorado Plateau  

NSDL National Science Digital Library

This web page provides a general description of the geology of the Colorado Plateau. Topics include information about the various geologic environments and processes active during the Precambrian and the Paleozoic, Mesozoic and Cenozoic Eras.

Colorado Plateau Field Institute


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.



Geology of the National Parks  

NSDL National Science Digital Library

This resource provides information about United States Geological Survey (USGS) resources and activities associated with National Parks. Users can choose from a selection of links that access items on park geology, virtual trips, research projects, and general topics such as plate tectonics, rocks and minerals, shorelines, glaciers, and many more. Links to geologic information for individual parks are arranged by alphabet, by state, or by geologic province.


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



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).



E-print Network

). This geologically based age estimation from Australia agrees with those from south China, where continental rifting Australia Geology, January 2011; v. 39; no. 1; p. 39­42; doi: 10.1130/G31461.1; 2 figures; Data RepositoryGEOLOGY, January 2011 39 INTRODUCTION The breakup processes of the Neoproterozoic supercontinent


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...


GEOLOGY, September 2010 823 INTRODUCTION  

E-print Network

GEOLOGY, September 2010 823 INTRODUCTION Deformations around transpressive plate boundaries numerical models constrained by global positioning system (GPS) observations and Geology, September 2010; v. 38; no. 9; p. 823­826; doi: 10.1130/G30963.1; 3 figures; 1 table. © 2010 Geological Society

Demouchy, Sylvie


The Lapworth Museum of Geology  

E-print Network

The Lapworth Museum of Geology 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



E-print Network




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


Geologic map of the Valley Mountain 15’ quadrangle, San Bernardino and Riverside Counties, California  

USGS Publications Warehouse

The Valley Mountain 15’ quadrangle straddles the Pinto Mountain Fault, which bounds the eastern Transverse Ranges in the south against the Mojave Desert province in the north. The Pinto Mountains, part of the eastern Transverse Ranges in the south part of the quadrangle expose a series of Paleoproterozoic gneisses and granite and the Proterozoic quartzite of Pinto Mountain. Early Triassic quartz monzonite intruded the gneisses and was ductiley deformed prior to voluminous Jurassic intrusion of diorite, granodiorite, quartz monzonite, and granite plutons. The Jurassic rocks include part of the Bullion Mountains Intrusive Suite, which crops out prominently at Valley Mountain and in the Bullion Mountains, as well as in the Pinto Mountains. Jurassic plutons in the southwest part of the quadrangle are deeply denuded from midcrustal emplacement levels in contrast to supracrustal Jurassic limestone and volcanic rocks exposed in the northeast. Dikes inferred to be part of the Jurassic Independence Dike Swarm intrude the Jurassic plutons and Proterozoic rocks. Late Cretaceous intrusion of the Cadiz Valley Batholith in the northeast caused contact metamorphism of adjacent Jurassic plutonic rocks. The Tertiary period saw emplacement of basanitoid basalt at about 23 Ma and deposition of Miocene and (or) Pliocene ridge-capping gravels. An undated east-dipping low-angle normal fault zone in the Pinto Mountains drops hanging-wall rocks eastward and may account for part of the contrast in uplift history across the quadrangle. The eastern Transverse Ranges are commonly interpreted as severely rotated clockwise tectonically in the Neogene relative to the Mojave Desert, but similar orientations of Jurassic dike swarms suggest that any differential rotation between the two provinces is small in this quadrangle. The late Cenozoic Pinto Mountain Fault and other strike-slip faults cut Quaternary deposits in the quadrangle, with two northwest-striking faults cutting Holocene deposits. Geographic Information System and metadata on most geologic features are available on the Geologic map of the Sheep Hole Mountains 30’ by 60’ quadrangle, U.S. Geological Survey map MF–2234, scale 1:100,000, available at

Howard, Keith A.; Bacheller, John; Fitzgibbon, Todd T.; Powell, Robert E.; Allen, Charlotte M.



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


Geologic Map of the Valles Caldera, Jemez Mountains, New Mexico  

NASA Astrophysics Data System (ADS)

Valles caldera is famous as the type locality of large resurgent calderas (Smith and Bailey, 1968), the location of a classic 260-300 °C liquid-dominated geothermal system (Goff and Gardner, 1994), and the site of a long-lived late Pleistocene lake (Fawcett et al., 2011). We have published a detailed color geologic map of the Valles caldera and surrounding areas at 1:50,000 scale obtainable from New Mexico Bureau of Geology and Mineral Resources ( The new Valles map has been compiled from all or parts of nine 1:24,000 geologic maps completed between 2004 and 2008 (Bland, Cerro del Grant, Jarosa, Jemez Springs, Polvadera Peak, Redondo Peak, Seven Springs, Valle San Antonio, and Valle Toledo). Our map provides more detailed geology on the resurgent dome, caldera collapse breccias, post-caldera lava and tuff eruptions, intracaldera sedimentary and lacustrine deposits, and precaldera volcanic and sedimentary rocks than previous maps and incorporates recent stratigraphic revisions to the geology of the Jemez Mountains volcanic field. Three cross sections supported by surface geology, geophysical data and deep borehole logs (?4500 m) show an updated view of the caldera interior, depict a modern interpretation of caldera collapse and resurgence, and provide caldera-wide subsurface isotherms (?500 °C). A 30 page booklet included with the map contains extensive rock descriptions for 162 stratigraphic units and figures showing physiographic features, structural relations between Valles (1.25 Ma) and the earlier, comparably sized Toledo caldera (1.62 Ma), correlation charts of map units, and the distribution of pre- and post-caldera hydrothermal alteration styles, including recently documented zeolite-type alteration. Finally, the booklet includes a generalized model showing our interpretation of intracaldera structure and subjacent magma chambers, and relations of Valles to earlier Quaternary-Precambrian units.

Goff, F.; Gardner, J. N.; Reneau, S. L.; Kelley, S. A.; Kempter, K. A.; Lawrence, J. R.



Geologic Photo Field Trips to View Rocks, Geologic Structures, and Landforms in Introductory Physical Geology  

NSDL National Science Digital Library

Field photographs are used to enhance the instruction in teaching rocks, geologic structures, and landforms in Introductory Physical Geology lecture at East Carolina University. The field photographs are used to enhance the visual component of Physical Geology and are focused on rock outcrops (igneous, sedimentary, and metamorphic), geologic structures (faults and folds), and landforms (volcanic, weathering-erosion, mass wasting, fluvial, wind-desert, coastal, and karst).

Stephen B. Harper


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



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.


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


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.


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.



Geology of Britain Viewer  

NSDL National Science Digital Library

If you've ever wanted to wander from John O'Groats to the Cotswolds without leaving your desk, this most wonderful website is for you. Created by the British Geological Survey, the Geology of Britain viewer helps interested parties learn more about the landforms in their backyards. After opening the viewer, visitors can click on an area of interest to look at everything from possible earthquake threats to rock layers to soil composition and more. Visitors should note that they can zoom in on the map and also use place names to refine their searches via the Go to Location button. Additionally, the basemap can be modified to show satellite photographs or various street maps as overlays. Finally, the site contains walking guides for several regions of Britain that might be helpful for those with a penchant for perambulation.


AGI: American Geological Institute  

NSDL National Science Digital Library

The American Geological Institute (AGI) created this website to promote its work dedicated to geoscientific services and outreach. The Information Services provides users with information on data repository systems and the GEoRef database. Students and educators can learn about professional development, conferences, scholarships, and more. The website provides action alerts, discussing key issues affecting geosciences in the federal government. Scientists can find a helpful human resources guide discussing geoscience careers and educational departments.


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.

Russell McDuff


Coastal Geological Processes  

NSDL National Science Digital Library

Coastlines are places of continuous, often dramatic geological activity. They change daily and seasonally, but especially over long time periods. This interactive feature discusses the forces that help shape coastal landforms like cliffs and beaches. Topics include waves, tides, and currents; weathering, erosion, and deposition; and other factors, such as the activity of organisms and human modifications. A background essay and discussion questions are included.


Greater Yellowstone Geology  

NSDL National Science Digital Library

This site features a collection of papers and maps about the Yellowstone hotspot by Dr. Ken Pierce of the Northern Rocky Mountain Science Center, an expert in the field. Papers on this site address topics such as Yellowstone glaciation, tracking the hotspot, the Yellowstone plume head, and a seven-day field trip guide to the quaternary geology and ecology of the Greater Yellowstone Ecosystem. Each downloadable paper map is listed with a brief description and a full citation.

Mountain Prairie Institute


Geologic Cross Sections  

NSDL National Science Digital Library

For this project, students must select a several hundred kilometer long section of Earth's surface, ideally crossing one or more major plate boundaries and research all major tectonic events to construct a cross section. Students should also take into account other factors like age of the ocean floor, average elevation and gravity anomalies across their area. The purpose is to demonstrate the geologic/tectonic history of their cross section and present it in a clear, concise summary.

Sharon Browning


Medical Geology in Africa  

Microsoft Academic Search

\\u000a A large body of evidence points to significant health effects resulting from our interactions with the physical environment\\u000a and we continue to recognise connections between geological materials and processes and human and animal disease. In Africa,\\u000a these relationships have been observed for many years, but only recently have any real attempts been made to formalise their\\u000a study. Africa is a

T. C. Davies


Geology - Plate Tectonics  

NSDL National Science Digital Library

Visitors to this site can learn about the theory of plate tectonics, the history of its development, and the mechanisms that drive the formation, movement, and destruction of continents and tectonic plates. A selection of animations depicts the movements of crustal plates and continents through time. Each animation is accompanied by an interactive time scale that provides links to descriptions of the geology and paleontology of the selected era or period.


Geologic processes influence the effects of mining on aquatic ecosystems  

USGS Publications Warehouse

Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments classified as “historically mined” or “unmined,” and based on mineral-deposit criteria, to determine whether water and sediment quality were influenced by naturally occurring mineralized rock, by historical mining, or by a combination of both. By accounting for different geologic sources of metals to the environment, we were able to distinguish aquatic ecosystems limited by metals derived from natural processes from those due to mining. Elevated concentrations of metals in water and sediment were not restricted to mined catchments; depauperate aquatic communities were found in unmined catchments. The type and intensity of hydrothermal alteration and the mineral deposit type were important determinants of water and sediment quality as well as the aquatic community in both mined and unmined catchments. This study distinguished the effects of different rock types and geologic sources of metals on ecosystems by incorporating basic geologic processes into reference and baseline site selection, resulting in a refined assessment. Our results indicate that biomonitoring studies should account for natural sources of metals in some geologic environments as contributors to the effect of mines on aquatic ecosystems, recognizing that in mining-impacted drainages there may have been high pre-mining background metal concentrations.

Schmidt, Travis S.; Clements, William H.; Wanty, Richard B.; Verplanck, Philip L.; Church, Stanley E.; San Juan, Carma A.; Fey, David L.; Rockwell, Barnaby W.; DeWitt, Ed H.; Klein, Terry L.



Geologic processes influence the effects of mining on aquatic ecosystems.  


Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments classified as "historically mined" or "unmined," and based on mineral-deposit criteria, to determine whether water and sediment quality were influenced by naturally occurring mineralized rock, by historical mining, or by a combination of both. By accounting for different geologic sources of metals to the environment, we were able to distinguish aquatic ecosystems limited by metals derived from natural processes from those due to mining. Elevated concentrations of metals in water and sediment were not restricted to mined catchments; depauperate aquatic communities were found in unmined catchments. The type and intensity of hydrothermal alteration and the mineral deposit type were important determinants of water and sediment quality as well as the aquatic community in both mined and unmined catchments. This study distinguished the effects of different rock types and geologic sources of metals on ecosystems by incorporating basic geologic processes into reference and baseline site selection, resulting in a refined assessment. Our results indicate that biomonitoring studies should account for natural sources of metals in some geologic environments as contributors to the effect of mines on aquatic ecosystems, recognizing that in mining-impacted drainages there may have been high pre-mining background metal concentrations. PMID:22645817

Schmidt, Travis S; Clements, William H; Wanty, Richard B; Verplanck, Philip L; Church, Stanley E; San Juan, Carma A; Fey, David L; Rockwell, Barnaby W; DeWitt, Ed H; Klein, Terry L



The Geology of Callisto  

NASA Technical Reports Server (NTRS)

The geology of Callisto is not boring. Although cratered terrain dominates Callisto (a key end-member of the Jovian satellite system), a number of more interesting features are apparent. Cratered terrain is broken into irregular map-able bright and dark subunits that vary in albedo by a factor of 2, and several relatively smooth units are depleted of small craters. Some of these areas may have been volcanically resurfaced. Lineaments, including parallel and radial sets, may be evidence for early global tectonism. Frost deposition occurs in cold traps, and impact scars have formed from tidally disrupted comets. Geologic evidence suggests that Callisto does have a chemically differentiated crust. Central pit and central dome craters and palimpsests are common. The preferred interpretation is that a relatively ice-rich material, at depths of 5 km or more, has been mobilized during impact and exposed as domes or palimpsests. The close similarity in crater morphologies and dimensions indicates that the outermost 10 km or so of Callisto may be as differentiated as on Ganymede. The geology of cratered terrain on Callisto is simpler than that of cratered terrain on Ganymede, however. Orbital evolution and tidal heating may provide the answer to the riddle of why Callisto and Ganymede are so different (Malhotra, 1991). We should expect a few surprises and begins to answer some fundamental questions when Callisto is observed by Galileo in late 1996.

Schenk, Paul M.



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



Amazing Altered Books  

ERIC Educational Resources Information Center

Linda Kieling, an art teacher at Rosemont Ridge Middle school in West Linn, Oregon, describes an altered book art project she introduced to her students. Alteration of books is a form of recycling that started in the eleventh century when Italian monks recycled old manuscripts written on vellum by scraping off the ink and adding new text and…

Kieling, Linda W.



Viruses as new agents of organomineralization in the geological record.  


Viruses are the most abundant biological entities throughout marine and terrestrial ecosystems, but little is known about virus-mineral interactions or the potential for virus preservation in the geological record. Here we use contextual metagenomic data and microscopic analyses to show that viruses occur in high diversity within a modern lacustrine microbial mat, and vastly outnumber prokaryotes and other components of the microbial mat. Experimental data reveal that mineral precipitation takes place directly on free viruses and, as a result of viral infections, on cell debris resulting from cell lysis. Viruses are initially permineralized by amorphous magnesium silicates, which then alter to magnesium carbonate nanospheres of ~80-200?nm in diameter during diagenesis. Our findings open up the possibility to investigate the evolution and geological history of viruses and their role in organomineralization, as well as providing an alternative explanation for enigmatic carbonate nanospheres previously observed in the geological record. PMID:24989676

Pacton, Muriel; Wacey, David; Corinaldesi, Cinzia; Tangherlini, Michael; Kilburn, Matt R; Gorin, Georges E; Danovaro, Roberto; Vasconcelos, Crisogono



Geologic Mapping and Geologic History: Sheep Mountain, Wyoming  

NSDL National Science Digital Library

Half way through the second semester of our year-long integrated Sed/Strat and Structure course we travel to Sheep Mountain, Wyoming where the students spend 5 days describing and measuring section and the constructing geologic and structural maps. The field data gathered then form the basis for a paper titled: "Geologic History of the Sheep Mountain Region". In addition to simply making geologic maps, stratigraphic sections and structural cross-sections, the students have to put the local geology into the broader contexts of the Big Horn Basin and sequences of western orogenies.

Lawrence L. Malinconico


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.



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.



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.


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.


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.



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.


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.


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.


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.



Multi- and hyperspectral geologic remote sensing: A review  

NASA Astrophysics Data System (ADS)

Geologists have used remote sensing data since the advent of the technology for regional mapping, structural interpretation and to aid in prospecting for ores and hydrocarbons. This paper provides a review of multispectral and hyperspectral remote sensing data, products and applications in geology. During the early days of Landsat Multispectral scanner and Thematic Mapper, geologists developed band ratio techniques and selective principal component analysis to produce iron oxide and hydroxyl images that could be related to hydrothermal alteration. The advent of the Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) with six channels in the shortwave infrared and five channels in the thermal region allowed to produce qualitative surface mineral maps of clay minerals (kaolinite, illite), sulfate minerals (alunite), carbonate minerals (calcite, dolomite), iron oxides (hematite, goethite), and silica (quartz) which allowed to map alteration facies (propylitic, argillic etc.). The step toward quantitative and validated (subpixel) surface mineralogic mapping was made with the advent of high spectral resolution hyperspectral remote sensing. This led to a wealth of techniques to match image pixel spectra to library and field spectra and to unravel mixed pixel spectra to pure endmember spectra to derive subpixel surface compositional information. These products have found their way to the mining industry and are to a lesser extent taken up by the oil and gas sector. The main threat for geologic remote sensing lies in the lack of (satellite) data continuity. There is however a unique opportunity to develop standardized protocols leading to validated and reproducible products from satellite remote sensing for the geology community. By focusing on geologic mapping products such as mineral and lithologic maps, geochemistry, P-T paths, fluid pathways etc. the geologic remote sensing community can bridge the gap with the geosciences community. Increasingly workflows should be multidisciplinary and remote sensing data should be integrated with field observations and subsurface geophysical data to monitor and understand geologic processes.

van der Meer, Freek D.; van der Werff, Harald M. A.; van Ruitenbeek, Frank J. A.; Hecker, Chris A.; Bakker, Wim H.; Noomen, Marleen F.; van der Meijde, Mark; Carranza, E. John M.; Smeth, J. Boudewijn de; Woldai, Tsehaie



Pattern Alteration: Principles of Pattern Alteration  

E-print Network

or more inches larger than the high bust measurement. Fit across the upper chest is a wiser choice because of the difficulty of altering the upper chest, neck and shoulder areas. 2... and then put back together, the original lengthwise grainline should be maintained whenever possible. Back waist length Shoulder length Back shoulder width High bust Bust Waist3 8 9 1 2 5 Bodice back Waist 3 High hip Hip Skirt length 12 4 13 Skirt back...



Hydrothermal alteration in the Mount Hood Area, Oregon. Bulletin  

SciTech Connect

The report describes the hydrothermal alteration of numerous outcrop samples collected in the vicinity of Mount Hood, as well as drill cuttings from 13 of the geothermal drill holes for which the authors were able to obtain sample splits. The study is also an outgrowth of a geologic and mineral survey of the Mount Hood Wilderness area in compliance with the Wilderness Act which requires that the U.S. Geological Survey and the U.S. Bureau of Mines evaluate the mineral resource potential of certain specified parcels of government-owned land.

Bargar, K.E.; Keith, T.E.C.; Beeson, M.H.



Geological considerations for lunar telescopes  

NASA Technical Reports Server (NTRS)

The geological features of the Moon that may be advantageous for astronomical observations are listed and described. The Moon's geologic environment offers wondrous opportunities for astronomy and presents fascinating challenges for engineers designing telescope facilities on the lunar surface. The geologic nature of the stark lunar surface and the Moon's tenuous atmosphere are summarized. The Moon as a stable platform is described as is its atmosphere, surface temperatures, its magnetic field, its regolith, and its crater morphologies.

Taylor, G. Jeffrey



Tour of Park Geology: Fossils  

NSDL National Science Digital Library

This National Park Service Geology site provides links to tours of individual National Parks, Monuments, and Recreation Areas that contain fossils. Where appropriate, for each park, links are provided to park geology, maps, photographs, geologic research, related links, visitor information, multimedia resources, and teacher features (resources for teaching geology with National Park examples). The list includes places such as the Grand Canyon, Dinosaur National Monument, Yellowstone, and Death Valley, along with less well-known areas such as the John Day Fossil Beds National Monument in Oregon.


Petroleum geology of Kuwait  

SciTech Connect

Kuwait is located in the Arabian platform geologic province and the stable shelf tectonic environment of the Mesopotamian geosyncline, a sedimentary basin extending from the Arabian shield on the west to the Zagros Mountains of complex folding and faulting history, on the east. The sedimentary cover in Kuwait consists of a complete succession 25,000 ft (7,600 m) thick on top of the basement and ranges in age from Paleozoic to Holocene. The relative geologic stability and homogeneity over virtually all its depositional history resulted in an extraordinary areal continuity of reservoirs, seals, and source rocks, giving rise to the accumulation of the largest concentration of the hydrocarbon reserves in the world in giant and super-giant oil and gas fields. The structures are very large, gentle with modest closure. The seals are very efficient. Because of the wide extent of the lithologic units and only gentle tectonic deformation, large-scale horizontal migration is very efficient and the large structures have great storage capacity.

Youash, Y.



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... ................................................................................................................................................................................. Basic lengthening and shortening On the Personal Measurement Chart, determine the amount of alteration you need from line 7, shoulder to waist; line 13, skirt length; line 17, side length; and/or line 11-b, sleeve length. Do this alteration on front...



Guide to the geology of Australia  

Microsoft Academic Search

The geology of onshore continental Australia is presented as a series of data sheets in which each geological province or entity is described in terms of key geological parameters: age, size, margins, physiography, elements, stratigraphy, igneous activity, metamorphism, deformation, and economic geology. An outline is given of Australian landforms, and a short geological history is presented. The bulletin is designed

W. D. Palfreyman; J. S. Adkins



Montana State University 1 Geology Option  

E-print Network

Montana State University 1 Geology Option The Geology Option is a degree program designed and private sectors in fields such as petroleum geology, mining geology, seismology (including earthquake and volcanic risk assessment), hydrology (surface and ground water) natural-hazard geology, environmental clean

Maxwell, Bruce D.


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


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



Northeastern Regional geologic characterization report. Volume 1. Final report  

SciTech Connect

This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. For each of the states within the Northeastern Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geologic factor and variables include deep mines and quarries, rock mass extent, postemplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major ground-water discharge zones, ground-water resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crusal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline bodies; ground-water resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies. A discussion is also presented on the relationship between the US Department of Energy (DOE) Siting Guidelines (10 CFR 960) and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process.

Not Available



North Central Regional geologic characterization report. Volume 1. Final report  

SciTech Connect

This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geologic factor and variables include deep mines and quarries, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, groundwater resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies. A discussion is also presented of the relationship between the US Department of Energy Siting Guidelines (10 CFR 960) and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process. 43 figs., 15 tabs.

Not Available



Geologic map of Io  

USGS Publications Warehouse

Io, discovered by Galileo Galilei on January 7–13, 1610, is the innermost of the four Galilean satellites of the planet Jupiter (Galilei, 1610). It is the most volcanically active object in the Solar System, as recognized by observations from six National Aeronautics and Space Administration (NASA) spacecraft: Voyager 1 (March 1979), Voyager 2 (July 1979), Hubble Space Telescope (1990–present), Galileo (1996–2001), Cassini (December 2000), and New Horizons (February 2007). The lack of impact craters on Io in any spacecraft images at any resolution attests to the high resurfacing rate (1 cm/yr) and the dominant role of active volcanism in shaping its surface. High-temperature hot spots detected by the Galileo Solid-State Imager (SSI), Near-Infrared Mapping Spectrometer (NIMS), and Photopolarimeter-Radiometer (PPR) usually correlate with darkest materials on the surface, suggesting active volcanism. The Voyager flybys obtained complete coverage of Io's subjovian hemisphere at 500 m/pixel to 2 km/pixel, and most of the rest of the satellite at 5–20 km/pixel. Repeated Galileo flybys obtained complementary coverage of Io's antijovian hemisphere at 5 m/pixel to 1.4 km/pixel. Thus, the Voyager and Galileo data sets were merged to enable the characterization of the whole surface of the satellite at a consistent resolution. The United States Geological Survey (USGS) produced a set of four global mosaics of Io in visible wavelengths at a spatial resolution of 1 km/pixel, released in February 2006, which we have used as base maps for this new global geologic map. Much has been learned about Io's volcanism, tectonics, degradation, and interior since the Voyager flybys, primarily during and following the Galileo Mission at Jupiter (December 1995–September 2003), and the results have been summarized in books published after the end of the Galileo Mission. Our mapping incorporates this new understanding to assist in map unit definition and to provide a global synthesis of Io's geology.

Williams, David A.; Keszthelyi, Laszlo P.; Crown, David A.; Yff, Jessica A.; Jaeger, Windy L.; Schenk, Paul M.; Geissler, Paul E.; Becker, Tammy L.



New Zealand Antarctic geological programme  

Microsoft Academic Search

New Zealand has been directly and continuously involved in the geological exploration of the Ross Dependency since early in 1957 when Scott Base was established for the Trans-Antarctic Expedition. Later, United States logistic activities between New Zealand and McMurdo Sound, arising out of the IGY and its continuation, offered opportunities to exploit the Antarctic summer for geological field work, thus

R. W. Willett



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.




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


Geology of the Black Hills  

NSDL National Science Digital Library

This presents a virtual geology field trip of the Black Hills. The topics that are covered include the general geology of the area, engineering and environmental issues, economic uses such as gold mining and bentonite recovery, and fossils. This site also features a clickable map that displays the location, information, and photographs of interesting stops in the Black Hills.

South Dakota State University


Geologic History of Western US  

NSDL National Science Digital Library

This web-site is a presentation showing graphically the Proterozoic and Phanerozoic geologic history of the Southwestern United States. There is a text file providing a brief narrative of the geologic history, which links to map graphics for each period. The graphics contain a scale and have labeled features to better understand what is happening as time progresses.

Ronald Blakey


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


Geology of National Parks  

NSDL National Science Digital Library

Have you ever wondered what it would be like to take a historic tour of the Colorado River Canyon? Wonder no more, as this site from the U.S. Geological Survey makes just such a sojourn possible. Drawing on thousands of historic and contemporary photographs, views, documents, and other items, the USGS has created these fine 3D and photographic tours of dozens of national parks. On the site, visitors will find an alphabetical list of the parks, along with links to the 3D image galleries, standard image galleries, and selected online field guides. There's a great deal to recommend here, but visitors should definitely look at the stereograph images from the Powell Survey Expeditions of the Colorado River from 1871 and 1872 (in the "Other park-related resources" section) and the guidebook titled "Where's the San Andreas Fault?" Along with providing entertaining edification, this site might also spark some ideas for an upcoming trip.


Geology of Europa  

NASA Technical Reports Server (NTRS)

Europa is a rocky object of radius 1565 km (slightly smaller than Earth s moon) and has an outer shell of water composition estimated to be of order 100 km thick, the surface of which is frozen. The total volume of water is about 3 x 10(exp 9) cubic kilometers, or twice the amount of water on Earth. Moreover, like its neighbor Io, Europa experiences internal heating generated from tidal flexing during its eccentric orbit around Jupiter. This raises the possibility that some of the water beneath the icy crust is liquid. The proportion of rock to ice, the generation of internal heat, and the possibility of liquid water make Europa unique in the Solar System. In this chapter, we outline the sources of data available for Europa (with a focus on the Galileo mission), review previous and on-going research on its surface geology, discuss the astrobiological potential of Europa, and consider plans for future exploration.

Greeley, R.; Chyba, C.; Head, J. W.; McCord, T.; McKinnon, W. B.; Pappalardo, R. T.



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.


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.



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.



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




E-print Network

CALIFORNIA ENERGY COMMISSION GEOLOGIC CARBON SEQUESTRATION STRATEGIES FOR CALIFORNIA that served as the foundational material for this report: John Clinkenbeard of the California Geological Geological Survey and Howard Herzog of the Massachusetts Institute of Technology. We would like to express



E-print Network

CALIFORNIA ENERGY COMMISSION GEOLOGIC CARBON SEQUESTRATION STRATEGIES FOR CALIFORNIA that provided much of the foundational material for this report: John Clinkenbeard of the California Geological and John Clinkenbeard of the California Geological Survey, and Howard Herzog of the Massachusetts


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, Applied Geology and Geoscience 30 Course descriptions 36 Masters and PhD programmes 52 The Masters

Goodman, James R.


Geological assessing of urban environments with a systematic mapping survey: The 1:5000 urban geological map of Catalonia  

NASA Astrophysics Data System (ADS)

The ground features of urban areas and the geologic processes that operate on them are, in general, strongly altered from their natural original condition as a result of anthropogenic activities. Assessing the stability of the ground, the flooding areas, and, the health risk as a consequence of soil pollution, are, among others, fundamental topics of urban areas that require a better understanding. The development of systematic urban geological mapping projects provides valuable resources to address these issues. Since 2007, the Institut Geologic de Catalunya (IGC) runs an urban geological mapping project, to provide accurate geologic information of county capitals and towns of more than 10000 inhabitants of Catalonia. The urban zones of 131 towns will be surveyed for this project, totalizing an area of about 2200 km2 to be mapped in 15 years. According to the 2008 census, the 82 % of the population of Catalonia (7.242.458 inhabitants) lives in the areas to be mapped in this project. The mapping project integrates in a GIS environment the following subjects: - Data from pre-existing geotechnical reports, historical geological and topographical maps and, from historical aerial photographs. - Data from available borehole databases. - Geological characterization of outcrops inside the urban network and neighbouring areas. - Geological, chemical and physical characterisation of representative rocks, sediments and soils. - Ortophotographs (0.5 m pixel size) and digital elevation models (5 meter grid size) made from historical aerial photographs, to depict land use changes, artificial deposits and geomorphological elements that are either hidden or destroyed by urban sprawl. - Detailed geological mapping of quaternary sediments, subsurface bedrock and artificial deposits. - Data from subsurface prospection in areas with insufficient or confuse data. - 3D modelling of the main geological surfaces such as the top of the pre-quaternary basement. All the gathered data is harmonised and stored it in a database. The analysis of the database allows to compile and print the 1:5000 scale urban geological map according to the 1:5000 topographic grid of Catalonia. The map is composed by a principal map, geologic cross sections and several complementary maps, charts and tables. Regardless of the geological map units, the principal map also includes the main artificial deposits (such as infilled river valleys and road embankments), very recent or current superficial deposits, contours of outcropping areas, structural data and other relevant information gathered in stations, sampling points, boreholes indicating the thickness of artificial deposits and the depth of the pre-quaternary basement, contour lines of the top of the pre-quaternary basement surface and, water level data. The complementary maps and charts may change depending on the gathered data, the geological features of the area and the urban typology. However, the most representative complementary maps that includes the printed urban map are the quaternary subsurface bedrock map and the isopach map of thickness of quaternary and anthropogenic deposits. The map also includes charts and tables of relevant physical and chemical parameters of the geological materials, harmonised downhole lithological columns from selected boreholes, and, photographs and figures illustrating the geology of the mapped area and how urbanisation has changed the natural environment. The object of this systematic urban mapping survey is to provide a robust database to be used in targeted studies related to urban planning, geoengineering works, soil pollution and other important environmental issues that society should deal in the future.

Vilà, Miquel; Pi, Roser; Cirés, Jordi; de Paz, Ana; Berástegui, Xavier



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.


Washington Division of Geology and Earth Resources  

NSDL National Science Digital Library

This website contains information about the geology of Washington State, provided by the Division of Natural Resources (DNR). It includes details about geologic hazards, such as earthquakes, volcanoes, landslides, tsunamis, and coal mine subsidence; geologic mapping, including a geologic map of the state; mine reclamation programs and energy regulation; downloadable publications; geology of the state by region, and by major geologic events from the Precambrian to Cenozoic; and information about the library with a Digital Bibliography of the Geology and Mineral Resources of Washington. The education section contains the Earth Connections series with lessons and experiments relating to geology within Washington state. There are many links provided for more information.


Altered Genes, Altered Metabolism - Longer Life?  

NSDL National Science Digital Library

Studying a tiny worm, Caenorhabditis elegans, scientists discovered that a gene which regulates glucose (sugar) metabolism may also enhance longevity. The principle investigator, Dr. David Finkelstein, says, "this finding suggests that altering glucose metabolism could be a key to slowing aging in higher organisms, even perhaps in humans." Working with a variety of taxa from mice to monkeys, scientists interested in the causes of aging have recently made significant advances in scientists' understanding of the aging process. Researchers have long realized that aging and the pathologies associated with it have evolutionary, physiological and genetic causes, although the relative influence of each of these has been debated. By testing hypotheses in diverse fields, and with a variety of species (from short-lived to long-lived), researchers are growing closer to building an understanding of the mechanisms underlying the aging process.

National Institutes of Health (U.S.). National Institute on Aging.



Geology of Earth's Moon  

NSDL National Science Digital Library

First, researchers at the University of California, San Diego discuss the importance of studying earthquakes on the moon, also known as moonquakes, and the Apollo Lunar Seismic Experiment (1). Users can discover the problems scientists must deal with when collecting the moon's seismic data. The students at Case Western Reserve University created the second website to address three missions the Institute of Space and Astronautical Science (ISAS) has planned between now and 2010, including a mission to the moon (2). Visitors can learn about the Lunar-A probe that will be used to photograph the surface of the moon, "monitor moonquakes, measure temperature, and study the internal structure." Next, the Planetary Data Service (PDS) at the USGS offers users four datasets that they can use to create an image of a chosen area of the moon (3). Each dataset can be viewed as a basic clickable map; a clickable map where users can specify size, resolution, and projection; or an advanced version where visitors can select areas by center latitude and longitude. The fourth site, produced by Robert Wickman at the University of North Dakota, presents a map of the volcanoes on the moon and compares their characteristics with those on earth (4). Students can learn how the gravitational forces on the Moon affect the lava flows. Next, Professor Jeff Ryan at the University of South Florida at Tampa supplies fantastic images and descriptive text of the lunar rocks obtained by the Apollo missions (5). Visitors can find links to images of meteorites, terrestrial rocks, and Apollo landings as well. At the Science Channel website, students and educators can find a video clip discussing the geologic studies on the moon along with videos about planets (6). Users can learn about how studying moon rocks help scientists better understand the formation of the earth. Next, the Smithsonian National Air and Space Museum presents its research of "lunar topography, cratering and impacts basins, tectonics, lava flows, and regolith properties" (7). Visitors can find summaries of the characteristics of the moon and the main findings since the 1950s. Lastly, the USGS Astrogeology Research Program provides archived lunar images and data collected between 1965 and 1992 by Apollo, Lunar Orbiter, Galileo, and Zond 8 missions (8). While the data is a little old, students and educators can still find valuable materials about the moon's topography, chemical composition, and geology.


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.



BS in GEOLOGY (694022) MAP Sheet Department of Geological Sciences  

E-print Network

Communication First-Year Writing Adv Written & Oral Communication Quantitative Reasoning Languages of Learning Geol 460 Economic and Resource Geology Geol 476 Intro to Seismic Interpretation Geol 480 Paleontology 4

Seamons, Kent E.


Identification of Crystalline Minerals in Volcanic Alteration Products and Applications to the Surface of Mars  

NASA Technical Reports Server (NTRS)

Visible, infrared and Mossbauer spectra have been measured for fine-grained alteration products of volcanic tephra and ash. Comparison of the spectral and chemical properties for different size separates and related samples provides information about the crystalline materials in these samples and how they may have formed. Hydrothermal processes can increase the alteration rates of the primary minerals and glass and provide S, Fe and/or water for formation of sulfates and hydrated minerals. Identification of crystalline alteration minerals on Mars may indicate hydrothermal alteration and sites of interesting geologic processes.

Bishop, J. L.; Madsen, M. B.; Murad, E.; Wagner, P. A.



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.


Geol 102 Historical Geology The Geologic Timescale 2012  

E-print Network

Geol 102 Historical Geology The Geologic Timescale 2012 EON ERA PERIOD (Special Units) EPOCH Range.332 Oligocene 33.9 - 23.03 Eocene 56.0 - 33.9 Paleocene 66.0 - 56.0 Cretaceous 145.0 - 66.0 Jurassic 201.3 - 145.0 Triassic 252.2 - 201.3 Permian 298.9 - 252.2 Pennsylvanian Sub-period 323.2 - 298.9 Mississippian Sub-period

Holtz Jr., Thomas R.


Pattern Alteration: Prominent Posture Problems  

E-print Network

Figure 7. #24;.................................................................................................................................................................................. Upper Curvature of the Spine This posture problem, which... for the round back alteration to determine how much you need to alter for upper curvature of the spine. Allow for additional width across the upper back just below the base of the neck. To alter, first follow the directions for altering bodice patterns...



Links between carbonate alteration in orogenic gold deposits and alkaline magmatism  

NASA Astrophysics Data System (ADS)

During the Miocene, orogenic gold deposits and lamprophyric magmas were emplaced contemporaneously in the proto-Southern Alps of New Zealand. These two systems have some striking similarities such as (1) the shared preferred orientations of the gold-bearing structures and the lamprophyric dikes, (2) the association with extensive, structurally controlled (dominantly Fe-rich) carbonate alteration, and (3) the shallow emplacement level into a quartzofeldspathic terrane. The abundance of the carbonate alteration is particularly notable as crustal sources for the CO2 such as marbles or carbonate minerals within the host rocks are very rare. A possible source could be related to the alkaline magmatic suite which, N of the study area, also contains mantle-derived carbonatites. To ascertain whether this could be the case, we have examined the geochemistry and isotopic properties of the Fe-carbonates that have precipitated in both systems, in veins as well as as replacing minerals within the host rock. The alteration haloes extend up to 10s of metres into the wallrock, where the replacement of metamorphic minerals such as chlorite and epidote distal to the fault zone attests to an extensive flux of CO2-rich fluids. Trace element data from these haloes, obtained in-situ using LA-ICP-MS, reveals introduction, mobilisation and redeposition of major and trace elements, such as Ca, K, Sr and REE. Sr isotope and trace element data suggest that the Fe-carbonates related to the lamprophyres have at least partly a genetic link to the carbonatites. Thus, some of the Miocene CO2 appears to have had a mantle origin. The carbonates related to the gold-bearing structures have more radiogenic 87Sr/86Sr ratios, which may be due to the interaction of the fluid with the relatively radiogenic host rocks as the signatures seem to depend on the type of wall rock (quartzofeldspathic- or greenschist). Tests are in progress to establish whether the gold-bearing carbonates could have formed by interaction of mantle derived fluids and crustal rocks.

Wellnitz, Katrin; Scott, James; Palin, Michael; Craw, Dave



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...



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



Immunization alters body odor.  


Infections have been shown to alter body odor. Because immune activation accompanies both infection and immunization, we tested the hypothesis that classical immunization might similarly result in the alteration of body odors detectable by trained biosensor mice. Using a Y-maze, we trained biosensor mice to distinguish between urine odors from rabies-vaccinated (RV) and unvaccinated control mice. RV-trained mice generalized this training to mice immunized with the equine West Nile virus (WNV) vaccine compared with urine of corresponding controls. These results suggest that there are similarities between body odors of mice immunized with these two vaccines. This conclusion was reinforced when mice could not be trained to directly discriminate between urine odors of RV- versus WNV-treated mice. Next, we trained biosensor mice to discriminate the urine odors of mice treated with lipopolysaccharide (LPS; a general elicitor of innate immunological responses) from the urine of control mice. These LPS-trained biosensors could distinguish between the odors of LPS-treated mouse urine and RV-treated mouse urine. Finally, biosensor mice trained to distinguish between the odors of RV-treated mouse urine and control mouse urine did not generalize this training to discriminate between the odors of LPS-treated mouse urine and control mouse urine. From these experiments, we conclude that: (1) immunization alters urine odor in similar ways for RV and WNV immunizations; and (2) immune activation with LPS also alters urine odor but in ways different from those of RV and WNV. PMID:24524972

Kimball, Bruce A; Opiekun, Maryanne; Yamazaki, Kunio; Beauchamp, Gary K



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.



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)



A primer in lunar geology  

NASA Technical Reports Server (NTRS)

Primary topics in lunar geology range from the evolution of the solar system to lunar photointerpretation, impact crater formation, and sampling to analyses on various Apollo lunar landing site geomorphologies.

Greeley, R. (editor); Schultz, P. H. (editor)



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



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 ...

Laura Guertin



E-print Network

Use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. Copies of this report can be obtained from: For additional information,

Maj Jeff Cornell (afcee; Mario Ierardi (afbca; Dr. Javier Santillan (afcee; Lt. Col; Daniel L. Welch; Kathy Davies; Epa Region; Richard G. Mach, Jr.; (southwest Division; Johnette Shockley; Paul M. Bergstr; South Carolina; Chris A. Guerre (california; David Randolph (tennessee; A. Vroblesky; Charles G. Groat


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....


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.


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.



Field Trip Guide to Serpentinite, Silica-Carbonate Alteration, and Related Hydrothermal Activity in the Clear Lake Region, California  

SciTech Connect

This guide is designed to familiarize scientists with the geology, structure, alteration, and fluids typical of California serpentinites for purposes of carbon dioxide sequestration (Lackner et al., 1995). Goff et al. (1997) and Goff and Lackner (1998) describe the geology and geochemistry of some of the serpentinites from this area. Mechanisms of silica-carbonate alteration were outlined by Barnes et al. (1973). Donnelly-Nolan et al. (1993) most recently reviewed relations between regional hydrothermal alteration and Quarternary volcanic activity. Stanley et al. (1998) summarized geophysical characteristics of the region.

Fraser Goff; George Guthrie



The Bureau of Economic Geology  

NSDL National Science Digital Library

The homepage of the Texas Bureau of Economic Geology provides links to information on the Bureau's research and industrial associates programs, its publications, news and events, and presentations by Bureau staff. A section for teachers and students includes on-line learning modules, which investigate earth science topics including soils, meteorites, floods and oil wells, as well as a coastal monitoring program for high school students and publications of general interest on Texas geology.


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.



Geology Field Trips as Performance Evaluations  

ERIC Educational Resources Information Center

One of the most important goals the author has for students in his introductory-level physical geology course is to give them the conceptual skills for solving geologic problems on their own. He wants students to leave his course as individuals who can use their knowledge of geologic processes and logic to figure out the extended geologic history…

Bentley, Callan



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


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


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


149Department of Geology Graduate Catalogue 201415  

E-print Network

149Department of Geology Graduate Catalogue 2014­15 Department of Geology Chairperson: Abdel. Assistant Instructor: P Hajj-Chehadeh, Abdel-Halim MS in Geology Candidates pursuing the Master of Science program in geology must complete seven graduate courses (21 cr.) and a thesis (9 cr.). Students may select


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


Geology of the Jabal Riah area, Kingdom of Saudi Arabia  

USGS Publications Warehouse

The Jabal Riah area is in the southern part of the Jibal al Hamdah quadrangle (lat 19?00'00'' to 19?07'S0'' N., long 45?37'30'' to 43?45'00' E.) in the southeastern Precambrian Shield, Asir Province, Kingdom of Saudi Arabia. The Jabal Mahanid group of ancient gold mines, which is part of the Jabal Ishmas-Wadi Tathlith gold belt, is in the west-central part of the area. Rocks in the Jabal Riah area consist of Precambrian layered metasedimentary and metavolcanic rocks intruded by Precambrian igneous rocks. The metamorphic rocks are, from oldest to youngest, interlayered hornblende and biotite schist, quartz-biotite schist, hornblende schist, serpentinite, and chlorite schist. The igneous rocks are, from oldest to youngest, diorite-gabbro including dikes, granodiorite, monzogranite-granodiorite, leucocratic quartz porphyry, rhyolite, and aplite and pegmatite dikes. A large area of jasper replaces serpentinite. On the valley floors, recent alluvium and pediment deposits overlie the bedrock. The structure of the area is dominated by a dome centered over the eastern border of the area; leucocratic quartz porphyry forms the core of the dome. Minor folds and faults are present. The Jabal Mahanid group of ancient gold mines is on a northwest-trending vein system, and major ancient mine areas are found where the system splits or changes direction. The veins consist of zones of brecciated and crushed rock, which are generally less than 0.5 m wide but may be as wide as 1 m. These zones contain quartz and calcite stringers and commonly are along hornblende schist-serpentinite contacts; however, they also cut both units. Most aplite, pegmatite, and quartz dikes in the area are thin and discontinuous and are intruded along the vein trend. Similar veins, at the same stratigraphic interval, have been found beyond the northeastern part of the map area. The veins contain detectable gold and silver (median gold, approximately 0.14 ppm; median silver, approximately 1 ppm). Gold and silver are most abundant in calcium-rich rocks and veins; silver was not detected in igneous rocks. Altered wall-rock zones are mineralized as much as 10 m away from the veins. Away from the Jabal Mahanid vein-system, silver was detected in the jasper. Gold and silver were detected in minor brecciated and sheared structures and in metasedimentary rocks. Gold was detected in sericitized margins of the leucocratic quartz porphyry, in unaltered rhyolite, and in aplite dikes. The presence of unusual amounts of gold and silver over a wide area is indicated by the ancient gold mines along veins at or near the hornblende schist-serpentinite contact in the map area and to the south in the Hajrah-Hamdah area and by the widespread evidence of precious metals in igneous rocks and other vein structures. A domed-shaped area, approximately 30 km in diameter, is outlined by the hornblende schist-serpentinite contact and has leucocratic quartz prophyry in the middle. Additional study of this area might reveal economic concentrations of gold and silver.

Wells, J.D.



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.



Southeastern Regional geologic characterization report. Volume 1. Final report  

SciTech Connect

This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in central Maryland; noncoastal Virginia, North Carolina, and South Carolina; and northern Georgia. For each of the states within the Southeastern Region, information is provided on the geological disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geological factor and variables include deep mines and quarries, rock mass extent, postemplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major ground-water discharge zones, ground-water resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on the age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline bodies; ground-water resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies.

Not Available




E-print Network

BACHELOR OF SCIENCE IN ENVIRONMENTAL GEOLOGY DEPARTMENT OF GEOLOGY AND PLANETARY SCIENCE WWW.GEOLOGY" for a complete range of advising information plus the latest Environmental Geology requirements. CORE COURSES (check each as completed): (30 credits) ____Choose one of the following introductory geology classes

Jiang, Huiqiang


The spectral analysis and information extraction for small geological target detection using hyperion image  

NASA Astrophysics Data System (ADS)

Imaging spectroscopic technique has been used for the mineral and rock geological mapping and alteration information extraction successfully with many reasonable results, but it is mainly used in arid and semi-arid land with low vegetation covering. In the case of the high vegetation covering, the outcrop of the altered rocks is small and distributes sparsely, the altered rocks is difficult to be identified directly. The target detection technique using imaging spectroscopic data should be introduced to the extraction of small geological targets under high vegetation covering area. In the paper, we take Ding-Ma gold deposit as the study area which located in Zhenan country, Shanxi province, the spectral features of the targets and the backgrounds are studied and analyzed using the field reflectance spectra, in addition to the study of the principle of the algorithms, some target detection algorithms which is appropriate to the small geological target detection are introduced. At last, the small altered rock targets under the covering of vegetation in forest are detected and discriminated in imaging spectroscopy data with the methods of spectral angle mapper (SAM), Constrained Energy Minimization (CEM) and Adaptive Cosine Estimator (ACE). The detection results are reasonable and indicate the ability of target detection algorithms in geological target detection in the forest area.

Li, Qingting; Wei, Xinxin; Zhang, Bing; Yan, Shouxun; Liu, Xiang



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.



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.


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.


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.


Relative Geologic Time and the Geologic Time Scale  

NSDL National Science Digital Library

Students are given a short introduction to fossils, strata, Steno's law of superposition, and the development of the geologic time scale from initial description of systems, through the realization that fossils could be used to correlate between systems, to the assembly of the modern geologic time scale. Then, each student in the course is given a sheet of paper with a simple stratigraphic column and associated fossils representing a geologic system on one side and a short description of the location and history of discovery of the system on the other. On a large wall, students then assemble four geologic columns from their systems representing mainland Europe, Great Britain, the Eastern U.S. and the Western U.S. using the fossils illustrated on their sheets to correlate systems. The instructor guides this process by placing the first system on the wall and by providing some narration as the columns take shape. Europe and Great Britain are assembled first, one sheet at a time, providing when completed the framework of the modern geologic time scale. Once this is up on the wall, the remaining students can assemble the other two columns in minutes using fossils to correlate between American and European systems. A temporal gap in the Grand Canyon sequence provides an opportunity to discuss the incompleteness of the rock record in any one place and a system composed of igneous and metamorphic rocks with no fossils is used to point out the difference between radiometric (absolute) and biostratigraphic (relative) dating.

Bret Bennington


Coordinated CRISM and Opportunity Observations to Characterize the Mineralogy and Geologic History of Meridiani Planum Outcrops  

NASA Astrophysics Data System (ADS)

The Opportunity Mars Exploration Rover has traversed over 30 km across Meridiani Planum since January 2004, acquiring numerous remote sensing and in-situ measurements of rocks and soils at dozens of locations. Over the past year Mars Reconnaissance Orbiter CRISM (0.362 to 3.92 micrometer imaging spectrometer) observations have been used to directly support planning of Opportunity traverses and locations for detailed remote sensing and in-situ measurements. As part of these coordinated observations CRISM's gimbaled optics have been used to spatially oversample acquisition of image data in the along-track direction (ATO or along track oversampled observations). This new acquisition mode allows sharpening the spatial detail from the normal ~18 m/pixel observations to values as small as ~6 m/pixel, with due formal consideration of the decrease in S/N with decreasing pixel sizes for retrieval of the 544 band spectra for each pixel. CRISM ATO observations show that mono-hydrated sulfates, most likely kieserite, outcrop on the walls of Victoria crater and the southeastern rim of Santa Maria crater. Unfortunately, the Victoria identifications are on the opposite side of the crater relative to where Opportunity made measurements of Victoria wall rocks. On the other hand, Opportunity was directed to Santa Maria's southeastern rim based on CRISM spectral reflectance data, spending the last solar conjunction period acquiring long-duration in-situ measurements of outcrop that likely carries the mono-hydrated sulfate signature. Additional ATO data collected over the relatively fresh, 2.3 km wide Ada crater located in southeastern Meridiani Planum show a similar mono-hydrated sulfate signature, implying that these deposits are widespread. Further, ATO observations allow detailed mapping of extensive hydrated sulfates in Botany Bay immediately to the south of Cape York, a rim segment of the largely buried, Noachian age Endeavour crater. Opportunity will cross these hydrated bedrock exposures on the way to Cape York outcrops. We will report on results from Opportunity's measurements on Victoria, Santa Maria, and Ada craters, together with measurements within Botany Bay, focusing on the synergistic use of Opportunity and CRISM observations to understand the mineralogy and geologic history of Meridiani Planum.

Arvidson, R. E.



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



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



Geologic setting, genesis and transformation of sulfide deposits in the northern part of Khetri copper belt, Rajasthan, India — an outline  

NASA Astrophysics Data System (ADS)

The present study is confined to the northern part of the Khetri copper belt that extends for about 100 km in northern Rajasthan. Mineralization is more or less strata-bound and is confined to the garnetiferous chlorite schist and banded amphibolite quartzite, occurring towards the middle of the Proterozoic Delhi Supergroup. Preserved sedimentary features and re-estimation of the composition of the pre-metamorphic rocks suggest that the latter were deposited in shallow marine environment characterized by tidal activity. Cordierite-orthoamphibole-cummingtonite rock occurring in the neighbourhood of the ores is discussed, and is suggested to be isochemically metamorphosed sediment. The rocks together with the ores were deformed in two phases and metamorphosed in two progressive and one retrogressive events of metamorphism. Study of the host rocks suggests that the maximum temperature and pressure attained during metamorphism are respectively 550 600°C and < 5.5 kb. Principal ore minerals in Madan Kudan are chalcopyrite, pyrrhotite, pyrite and locally magnetite. In Kolihan these are chalcophyrite, pyrrhotite and cubanite. Subordinate phases are sphalerite, ilmenite, arsenopyrite, mackinawite, molybdenite, cobaltite and pentlandite. The last two are very rare. Gangue minerals comprise quartz, chlorite, garnet, amphiboles, biotite, scapolite, plagioclase and graphite. The ores are metamorphosed at temperatures > 491°C. Sulfide assemblages are explained in terms of fS 2 during metamorphism. Co-folding of the ore zone with the host rocks, confinement of the ores to the carbonaceous pelites or semi-pelitic rocks, strata-bound and locally even stratiform nature of the orebodies, lack of finite ‘wall rock alteration’, metamorphism of the ores in the thermal range similar to that for the host rocks, absence of spatial and temporal relationship with the granitic rocks of the region led the authors to conclude that the entire mineralization was originally sedimentary-diagenetic. Any loss of primitive features and development of incongruency are due to subsequent deformation and metamorphism to which the ores and their hosts were together subjected.

Sarkar, S. C.; Dasgupta, Somnath



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.


77 FR 6580 - National Cooperative Geologic Mapping Program (NCGMP) and National Geological and Geophysical...  

Federal Register 2010, 2011, 2012, 2013, 2014

...National Geological and Geophysical Data Preservation Program (NGGDPP...National Geological and Geophysical Data Preservation Program. DATES...National Geological and Geophysical Data Preservation Program Advisory Committee are open to the Public. Dated:...



Investigating the Geologic History of Southeast Minnesota by Constructing a Geologic Column  

NSDL National Science Digital Library

This activity is a field investigation where students gather data on rock types and geologic formations to construct a geologic column that will help them to interpret the geologic history of the Cannon Falls area.

Amanda Ludeman


Underground mining and deep geologic disposal - Two compatible and complementary activities  

SciTech Connect

Active and mature underground mining districts offer conditions favorable to deep geologic disposal because their geology is known in more detail, the feasibility of underground excavations has already been demonstrated, mining leaves distinctive footprints and records that alert subsequent generations to the anthropogenic alterations of the underground environment, and subsequent exploration and production proceeds with great care and accuracy to locate and generally to avoid old mine workings. Compatibility of mining with deep geologic waste disposal has been proven by decades of experience with safe storage and disposal in former mines and in the mined-out areas of still active mining operations. Mineral extraction around an intended repository reduces the incentive for future disturbance. Incidental features of mineral exploration and extraction such as lost circulation zones, allochthonous backfill, and permanent surface markers can deter future intrusion into a repository. Thus exploration and production of mineral resources should be compatible with, and complementary to, deep geologic waste disposal.

Rempe, N.T.



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


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.


pre or co-requisite Geology Course Prerequisite Chart  

E-print Network

pre or co-requisite Geology Course Prerequisite Chart 1101, 1102, 1103,1104, 1105 2250 3160 2500 hours geology junior standing; six hours geology depends on course senior standing, permission hours geology six hours geology Evolution of the Earth Geophysics Physical Geology , Historical Geology

Thaxton, Christopher S.


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.



Pattern Alteration: Sway Back  

E-print Network

back is a posture problem characterized by a distinct curve in the spine at the waistline and lower back. This curve actually shortens the length of the back along t poorly there. Garments with waistlines will have horizontal folds of fabric along... the center back just below the waist and the lower back. In one- piece dresses or jackets, fabric might stand away from the body and/or have horizontal folds along the center back (Fig.1). Determine the amount you need to alter by having someone pin...



Map showing potential metal-mine drainage hazards in Colorado, based on mineral-deposit geology  

USGS Publications Warehouse

This map, compiled by the U.S. Geological Survey (USGS) in cooperation with the Colorado Geological Survey (CGS) and the U. S. Bureau of Land Management (BLM), shows potential mine-drainage hazards that may exist in Colorado metal-mining districts, as indicated by the geologic characteristics of the mineral deposits that occur in the respective districts. It was designed to demonstrate how geologic and geochemical information can be used on a regional scale to help assess the potential for mining-related and natural drainage problems in mining districts, unmined mineralized areas, and surrounding watersheds. The map also provides information on the distribution of different mineral deposit types across Colorado. A GIS (Geographic Information System) format was used to integrate geologic, geochemical, water-quality, climate, landuse, and ecological data from diverse sources. Likely mine-drainage signatures were defined for each mining district based on: (1) a review of the geologic characteristics of the mining district, including mineralogy, trace-element content, host-rock lithology, and wallrock alteration, and; (2) results of site specific studies on the geologic controls on mine-drainage composition.

Plumlee, Geoffrey S.; Streufert, Randall K.; Smith, Kathleen S.; Smith, Steven M.; Wallace, Alan R.; Toth, Margo I.; Nash, J. Thomas; Robinson, Rob A.; Ficklin, Walter H.; Lee, Gregory K.



Importance of geology to fisheries management: Examples from the northeastern Gulf of Mexico  

USGS Publications Warehouse

Seafloor mapping of shelf-edge habitats in the northeastern Gulf of Mexico demonstrates how sidescan-sonar imagery, seismic-reflection profiling, video data, geologic mapping, sediment sampling, and understanding the regional geologic history can enhance, support, and guide traditional fisheries research and management. New data from the Madison Swanson and Steamboat Lumps Marine Reserves reveal complex benthic habitats consisting of high-relief calcareous pinnacles, low-relief karstic hardbottom, rocky outcrops several kilometers in length, and variable thickness of fine-grained and apparently mobile coarse-grained sediments. Our data also show that certain fish alter the landscape by clearing sediment from hardbottom areas (e.g., red grouper Epinephelus morio) and by burrowing extensively in fine-grained sediment (e.g., tilefish Lopholatilus chamaeleonticeps). The seafloor imagery and geologic maps show that (a) sea level fluctuations played a dominant role in the development of the present-day regional geology, and (b) habitats (and benthic communities) are tied closely to geologic character. Understanding the geologic setting allowed for efficient and representative sampling of the biology. The geologic data can be used to set meaningful boundaries for fishery reserves and to help predict habitats in areas that are not well mapped. This interdisciplinary work added value to traditional research disciplines by providing management with integrated tools to make better decisions. ?? Copyright by the American Fisheries Society 2003.

Scanlon, K.M.; Koenig, C.C.; Coleman, F.C.; Miller, M.



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.


Geology on a Sand Budget  

NSDL National Science Digital Library

Earth science teaches know how frustrating it can be to spend hundreds of dollars on three-dimensional (3-D) models of Earth's geologic features, only to use the models for a few class periods. To avoid emptying an already limited science budget, teachers can use a simple alternative to the expensive 3-D models--sand. Modeling geologic processes and features with sand is an effective way for teachers to promote student understanding of Earth science topics, quickly assess students' prior knowledge, and identify common misconceptions.

Jacqueline Kane



Geology of the American Southwest  

NASA Astrophysics Data System (ADS)

Scott Baldridge presents a concise guide to the geology of the Southwestern U.S. Two billion years of Earth history are represented in the rocks and landscape of the Southwest U.S., creating natural wonders such as the Grand Canyon, Monument Valley, and Death Valley. This region is considered a geologist's "dream", attracting a large number of undergraduate field classes and amateur geologists. The volume will prove invaluable to students and will also appeal to anyone interested in the geology and landscape of the region's National Parks.

Baldridge, W. Scott



Geology Programs and Disciplinary Accreditation  

NSDL National Science Digital Library

This report raises the question of whether accreditation may be coming to the geology discipline, and attempts to quantify the positions on accreditation of academic department heads/chairs. The study makes a distinction between institutional and specialized (or disciplinary) accreditation and explores attitudes toward both types. Results of the analysis are presented with a discussion of two methods of data interpretation, a multivariate analysis technique and the Chi square test for heterogeneity or independence. The report concludes that there is currently insufficient support for establishing disciplinary accreditation in geology.

Robert Corbett



A Geological Wonder: Niagara Falls  

NSDL National Science Digital Library

This lesson plan is part of the lesson plan library for grades 9-12. It focuses on the geological history of the Niagara Falls area, as well as the physical and geological processes that have formed this region. It includes objectives, materials, procedures, discussion questions, evaluation ideas, performing extensions, suggested readings, and vocabulary. There are videos available to order which complement this lesson, audio vocabulary, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.


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.


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.


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 ...


Pattern Alteration: Even Hip Circumference  

E-print Network

. 4). Place tissue paper under it. To complete either alteration: 5. Tape the pattern in place. 6. Redraw the seamline, the cutting line and the hemline (Figs. 5 and 6). Princess Dress or Six-Gored Skirt Alterations for a basic skirt apply to a dress... without a waist seam. Divide the amount of alteration you need by the number of seams, excluding any center front and back seams. Divide this number by two to determine how much to alter each seam allowance. If the pattern has to be altered more than 6...



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




E-print Network

GEOLOGY, April 2010 311 INTRODUCTION About 15 yr ago, the National Aeronautics and Space burial (Strom et al., 1994; Basilevsky and Head, 1998, 2002, 2006; Bullock et al., 1993), or (2's locally oldest surface unit (Basi- levsky and Head, 1998; Head and Basilevsky, 1998), although globally

Hansen, Vicki


Geology on a Sand Budget  

ERIC Educational Resources Information Center

Earth science teachers know how frustrating it can be to spend hundreds of dollars on three-dimensional (3-D) models of Earth's geologic features, to use the models for only a few class periods. To avoid emptying an already limited science budget, the author states that teachers can use a simple alternative to the expensive 3-D models--sand. She…

Kane, Jacqueline



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


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.


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



Structural Geology: Deformation of Rocks  

E-print Network

include the Michigan Basin, Illinois Basin, Cincinnati Arch, Nashville Dome, Black Hills, etc. #12;The #12;Fig. 7.15b. A small dome in Texas #12;Michigan Basin #12;Geologic Map of Michigan Basin #12 and basins - very broad features within continental interiors · complex folds - the result of very ductile

Kammer, Thomas


National Archive of Geological Photographs  

NSDL National Science Digital Library

Provided by the British Geological Survey, this site contains a database of more than 6,000 digitized images dedicated to the theme of earth sciences. The archive may be searched by keyword, advanced search, or browsed via galleries. Images are accompanied by descriptions of varying length. A wide range of photographic and digital products is available for purchase from BGS.


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...


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.

Bob Jorstad



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




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.

Lee Krystek


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.


GEOLOGICAL SCIENCES 694 Tectonic Geomorphology  

E-print Network

GEOLOGICAL SCIENCES 694 Tectonic Geomorphology Winter Quarter 2007 Lecture: TR 10-11:18, Orton 251: Required Textbooks Tectonic Geomorphology, Burbank and Anderson, 2001. ISBN: 0-632-04386-5 Course Objectives: To introduce students to fundamental problems in tectonic geomorphology in convergent

Schoenbohm, Lindsay


Geology and mineral deposits of the Jabal ash Shumta quadrangle, Kingdom of Saudi Arabia  

USGS Publications Warehouse

Rocks, structures, and mineral deposits which are the result of both the older Halaban petro-tectonic cycle and the younker Najd Wrench Fault deformation are present in the Ash Shumta area. Northward-trending belts of granitic rocks and folded, layered metavolcanic and metasedimentary rocks of the Halaban Formation which they intrude represent the effects of the Halaban cycle. These older rocks are everywhere transected and deformed by northwestward- and northeastward-striking fractures and strike-slip faults and by eastward-striking fractures and fracture-controlled silicic dikes which belong to the Najd Wrench Fault deformation. Several kinds of epigenetic mineral deposits of hydrothermal origin are present throughout the Ash Shumta area. All occur in or ape closely associated with structures of the Najd Wrench Fault deformation. The mineralization which produced the deposits is thought to have taken place during the period of deformation which produced the Najd Wrench Fault structures. The hydrothermal deposits include many metalliferous quartz veins most of which occur in three mineralized areas: two major areas at Jabal Ash Shumta and Jabal El Khom in the northern half of the quadrangle and a minor area along Wadj al Boharah in the southeastern part of the quadrangle. The metalliferous lodes possess the only economic potential in the area of the Jabal Ash Shumta quadrangle. These lodes consist mainly of gold and base metal-bearing quartz veins, some of which were mined for gold in ancient times. The mineralized area at Jabal Ash Shumta has the best of these veins. Higher temperature veins with wolframite as a major constituent and beryl as a minor one occur in a granite cupola in the eastern part of the El Khom area. These veins have altered, gneissen-like wall rocks. Although the grade of the veins is low at the surface, the made could increase at depth. The tungsten-bearing veins and El Khom area possess the greatest economic promise in the Jabal Ash Shumta quadrangle. They deserve detailed surface investigation followed if needed by exploration at depth.

Hummel, C.L.; Ankary, Abdullah O.



Geology Fieldnotes: Kobuk Valley National Park  

NSDL National Science Digital Library

This feature discusses the geology, landforms, glacial history, soils, and mineral resources of Kobuk Valley National Park. Links are provided to maps, visitor information, a history of gold prospecting in the area, and to related geology and conservation organizations.


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.



Park Geology: Tour of National Parks  

NSDL National Science Digital Library

A great site from the National Park Service, Geologic Resources Division provides information on geologic features of our national parks. The site is aimed at a young audience (K-8), but is a pleasure to browse for anyone. Organizing the site by geologic features (e.g., Hot Springs, Oldest Rocks, and Volcanoes) allows readers to compare the geology of various national parks and explore maps, photos and other related links.


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.


Planetary geology in the 1980s  

NASA Technical Reports Server (NTRS)

The geologic aspects of solar system studies are defined and the goals of planetary geology are discussed. Planetary geology is the study of the origin, evolution, and distribution of matter condensed in the form of planets, satellites, asteroids, and comets. It is a multidisciplinary effort involving investigators with backgrounds in geology, chemistry, physics, astronomy, geodesy, cartography, and other disciplines concerned with the solid planets. The report is primarily restricted to the kinds of experiments and observations made through unmanned missions.

Veverka, J.



Field guide to hydrothermal alteration in the White River altered area and in the Osceola Mudflow, Washington  

USGS Publications Warehouse

The Cenozoic Cascades arcs of southwestern Washington are the product of long-lived, but discontinuous, magmatism beginning in the Eocene and continuing to the present (for example, Christiansen and Yeats, 1992). This magmatism is the result of subduction of oceanic crust beneath the North American continent. The magmatic rocks are divided into two subparallel, north-trending continental-margin arcs, the Eocene to Pliocene Western Cascades, and the Quaternary High Cascades, which overlies, and is east of, the Western Cascades. Both arcs are calc-alkaline and are characterized by voluminous mafic lava flows (mostly basalt to basaltic andesite compositions) and scattered large stratovolcanoes of mafic andesite to dacite compositions. Silicic volcanism is relatively uncommon. Quartz diorite to granite plutons are exposed in more deeply eroded parts of the Western Cascades Arc (for example, Mount Rainier area and just north of Mt. St. Helens). Hydrothermal alteration is widespread in both Tertiary and Quaternary igneous rocks of the Cascades arcs. Most alteration in the Tertiary Western Cascades Arc resulted from hydrothermal systems associated with small plutons, some of which formed porphyry copper and related deposits, including copper-rich breccia pipes, polymetallic veins, and epithermal gold-silver deposits. Hydrothermal alteration also is present on many Quaternary stratovolcanoes of the High Cascades Arc. On some High Cascades volcanoes, this alteration resulted in severely weakened volcanic edifices that were susceptible to failure and catastrophic landslides. Most notable is the sector collapse of the northeast side of Mount Rainier that occurred about 5,600 yr. B.P. This collapse resulted in formation of the clay-rich Osceola Mudflow that traveled 120 km down valley from Mount Rainier to Puget Sound covering more than 200 km2. This field trip examines several styles and features of hydrothermal alteration related to Cenozoic magmatism in the Cascades arcs. The morning of the trip will examine the White River altered area, which includes high-level alteration related to a large, early Miocene magmatic-hydrothermal system exposed about 10 km east of Enumclaw, Washington. Here, vuggy silica alteration is being quarried for silica and advanced argillic alteration has been prospected for alunite. Clay-filled fractures and sulfide-rich, fine-grained sedimentary rocks of hydrothermal origin locally are enriched in precious metals. Many hydrothermal features common in high-sulfidation gold-silver deposits and in advanced argillic alteration zones overlying porphyry copper deposits (for example, Gustafson and Hunt, 1975; Hedenquist and others, 2000; Sillitoe, 2000) are exposed, although no economic base or precious metal mineralized rock has been discovered to date. The afternoon will be spent examining two exposures of the Osceola Mudflow along the White River. The Osceola Mudflow contains abundant clasts of altered Quaternary rocks from Mount Rainier that show various types of hydrothermal alteration and hydrothermal features. The mudflow matrix contains abundant hydrothermal clay minerals that added cohesiveness to the debris flow and helped allow it to travel much farther down valley than other, noncohesive debris flows from Mount Rainier (Crandell, 1971; Vallance and Scott, 1997). The White River altered area is the subject of ongoing studies by geoscientists from Weyerhaeuser Company and the U.S. Geological Survey (USGS). The generalized descriptions of the geology, geophysics, alteration, and mineralization presented here represent the preliminary results of this study (Ashley and others, 2003). Additional field, geochemical, geochronologic, and geophysical studies are underway. The Osceola Mudflow and other Holocene debris flows from Mount Rainier also are the subject of ongoing studies by the USGS (for example, Breit and others, 2003; John and others, 2003; Plumlee and others, 2003, Sisson and others, 2003; Vallance and others, 2003). Studies of hydrothermal alteration in the Osceola Mudflow are being used to bett

John, David A.; Rytuba, James J.; Ashley, Roger P.; Blakely, Richard J.; Vallance, James W.; Newport, Grant R.; Heinemeyer, Gary R.



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


Measuring Student Understanding of Geological Time  

ERIC Educational Resources Information Center

There have been few discoveries in geology more important than "deep time"--the understanding that the universe has existed for countless millennia, such that man's existence is confined to the last milliseconds of the metaphorical geological clock. The influence of deep time is felt in a variety of sciences including geology, cosmology, and…

Dodick, Jeff; Orion, Nir



Christopher U.S. Geological Survey  

E-print Network

Christopher Magirl U.S. Geological Survey 934 Broadway Suite 300 Tacoma, Washington 98402 Phone Research Hydrologist U.S. Geological Survey, Tacoma, Washington. September 2009 ­ present · Analyzing.S. Geological Survey, Tacoma, Washington. July 2008 ­ September 2009 · Developed geomorphic and GIS methodology


11 Years Engineering Geology Fieldwork in  

E-print Network

;14 dec 2001 11 years engineering geology in Falset - science from fieldwork - hack 2 What did we Produce ? Why did we ? #12;14 dec 2001 11 years engineering geology in Falset - science from fieldwork - hack 3 happy #12;14 dec 2001 11 years engineering geology in Falset - science from fieldwork - hack 4 Why keep

Hack, Robert


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.

Steve Dutch


Tour of Park Geology: Human Use Sites  

NSDL National Science Digital Library

This National Park Service (NPS) site provides links to geolgy field notes about National Parks, National Monuments, and National Recreation Areas having to do with geology and human use (such as mining). Information includes geology, photographs, multimedia tools, park maps, visitor information, geologic research, and additional links. Parks covered include Klondike Gold Rush National Historic Park, Alibates Flint Quarries National Monument, and more.


The Geologic Story of the Ocoee River  

NSDL National Science Digital Library

The United States Geological Survey (USGS) highlights the geology of the Ocoee River, in the scenic Cherokee National Forest of southeastern Tennessee. This report covers the geologic history of the area, from 750 million years ago (Precambrian) to the present. Uses of the river, from dams to mining, are also discussed.


Geology Fieldnotes: Great Basin National Park, Nevada  

NSDL National Science Digital Library

This Great Basin National Park site contains park geology information, park maps, visitor information, and teacher features (educational resources and links for teaching geology using National Park examples). The park geology section discusses the region's biogeography, glacial history, and the Lehman Caves. A park map and a features/relief map of the Great Basin National Park are included.


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


A publication of the Department of Geology  

E-print Network

#12;A publication of the Department of Geology Brigharn Young University Provo, Utah 84602 Editors W. Kenneth Hamblin Cynthia M. Gardner Brigham Young University Geology Studies is published semiannually by the department. Geology Studies consists of graduate-student and staff research

Seamons, Kent E.


, 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.


Geologic Windows Through Time on Mars  

Microsoft Academic Search

An overarching geologic theory, GEOMARS, coherently explains the various anomalies in the geologic history of Mars. Premises for a theory of martian geologic evolution include: (1) Mars is a water-rich terrestrial planet, (2) terrestrial planets should evolve through progressive stages of dynamical history (accretion, differentiation, tectonism) and mantle convection (magma ocean, plate tectonism, stagnant lid), and (3) the early history

J. M. Dohm; K. E. Kerry; J. Keller; V. R. Baker; W. V. Boynton; S. Maruyama



ABOUT THE JOURNAL One of the oldest journals in geology, The Journal of Geology has  

E-print Network

ABOUT THE JOURNAL One of the oldest journals in geology, The Journal of Geology has promoted the systematic philosophical and fundamental study of geology since 1893. The Journal publishes original research across a broad range of subfields in geology, including geophysics, geochemistry, sedimentology

Mateo, Jill M.


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.


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


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


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.


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.



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


Val Verde basin study integrates gravity, magnetic, geologic data  

SciTech Connect

In early 1990, a study integrating gravity, magnetic, surface geology and subsurface geology was completed of a 1,250 mile sector of the Val Verde basin. The study's objective was to develop a perspective of the region's structural framework and priority prospect leads for site-specific evaluation by the more definitive yet much more expensive geochemical and seismic methods. To achieve these objectives, two main principles were applied: (1) that the structural disturbance of near-surface sedimentary formations and/or the geochemical alteration products caused by the microseepage of hydrocarbons give rise to geophysically measurable lateral changes in formation density, magnetization, conductivity, and so forth; (2) that certain survey methods are suited for reconnaissance while others are best utilized in the detailed definition phase of an exploration program and that the most cost-effective program is one in which several methods appropriate to the geologic setting are systematically applied in their ascending order of cost and definition. In 1993, a significant wildcat discovery, the Tom Brown-Conoco 1 ACU Strawn Field, in Terrell County, Tex., was drilled within the boundary of one of the study's prospect leads. This article presents the information potential of each of the methods applied and the benefits of weighing the information from each type of data against that of the others to better define the configuration and priority of each prospect lead.

Land, J.P. (J.P. Land Associates Inc., Houston, TX (United States))



The commensurability of environmental geology and petroleum geology  

SciTech Connect

Environmental geology and petroleum geology are practical applications of pure geology. These two applied sciences differ with respect to their philosophical and ethical mandates. A good petroleum geologist finds hydrocarbons, but the role of a good environmental geologist is not well defined. If the good environmental geologist's role is not simply to protect the environment from the good petroleum geologist then how do the mandates of these geologists differ, yet remain compatible If the mandate of a good environmental geologist were to protect every natural resource from all managed use, then the good environmental geologist and the good petroleum geologist would forever be at war. This mandate provides no framework for agreement because it assumes the inherent worth of each natural resource is discoverable. If the mandate of a good environmental geologist is to discover how to maximize the long-term benefits of the managed use of natural resource, then both the good environmental geologist and the good petroleum geologist would agree that no natural resource has inherent worth. The value of a natural resource is not determined by what it is, but by how it enhances the quality of life for a particular class of sentient creatures. An instrumental theory of value will provide a medium for interim disagreement on how to enhance the quality of life for sentient creatures, and also will provide the means for a long-term agreement that the managed use of natural resources enhances the long-term quality of life for sentient creatures.

Argen, R.J.



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.



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



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


References on Ball Clay U.S. Geological Survey  

E-print Network

: Robert L. Virta James R. Herring U.S. Geological Survey U.S. Geological Survey 983 National Center BoxReferences on Ball Clay U.S. Geological Survey: Clay and Shale. U.S. Geological Survey (U.S. Bureau Quadrangle, Graves County, Kentucky: U.S. Geological Survey Geologic Quadrangle GQ-0457, Scale 1

409 Undergraduate Degrees Offered  

E-print Network

GEOLOGY Undergraduate Degrees Offered: Bachelor of Arts in Geology Bachelor of Science in Geology Secondary Education Program Minor in Geology Minor in Computer Applications Minor in Environmental Geology Minor in Space and Planetary Science Graduate Degrees Offered: M.A., M.S., M.A.T. and M


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


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.



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.



U.S. Geological Survey Geologic Carbon Sequestration Assessment  

NASA Astrophysics Data System (ADS)

The Energy Independence and Security Act of 2007 authorized the U.S. Geological Survey (USGS) to conduct a national assessment of potential geological storage resources for carbon dioxide (CO2) in consultation with the U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA) and State geological surveys. To conduct the assessment, the USGS developed a probability-based assessment methodology that was extensively reviewed by experts from industry, government and university organizations (Brennan et al., 2010, The methodology is intended to be used at regional to sub-basinal scales and it identifies storage assessment units (SAUs) that are based on two depth categories below the surface (1) 3,000 to 13,000 ft (914 to 3,962 m), and (2) 13,000 ft (3,962 m) and greater. In the first category, the 3,000 ft (914 m) minimum depth of the storage reservoir ensures that CO2 is in a supercritical state to minimize the storage volume. The depth of 13,000 ft (3,962 m) represents maximum depths that are accessible with average injection pressures. The second category represents areas where a reservoir formation has potential storage at depths below 13,000 ft (3,962 m), although they are not accessible with average injection pressures; these are assessed as a separate SAU. SAUs are restricted to formation intervals that contain saline waters (total dissolved solids greater than 10,000 parts per million) to prevent contamination of protected ground water. Carbon dioxide sequestration capacity is estimated for buoyant and residual storage traps within the basins. For buoyant traps, CO2 is held in place in porous formations by top and lateral seals. For residual traps, CO2 is contained in porous formations as individual droplets held within pores by capillary forces. Preliminary geologic models have been developed to estimate CO2 storage capacity in approximately 40 major sedimentary basins within the United States. More than 200 SAUs have been identified within these basins. The results of the assessment are estimates of the technically accessible storage resources based on present-day geological and engineering technology related to CO2 injection into geologic formations; therefore the assessment is not of total in-place resources. Summary geologic descriptions of the evaluated basins and SAUs will be prepared, along with the national assessment results. During the coming year, these results will be released as USGS publications available from In support of these assessment activities, CO2 sequestration related research science is being conducted by members of the project. Results of our research will contribute to current and future CO2 storage assessments conducted by the USGS and other organizations. Research topics include: (a) geochemistry of CO2 interactions with subsurface environments; (b) subsurface petrophysical rock properties in relation to CO2 injection; (c) enhanced oil recovery and the potential for CO2 storage; (d) storage of CO2 in unconventional reservoirs (coal, shale, and basalt); (e) statistical aggregation of assessment results; and (f) potential risks of induced seismicity.

Warwick, P. D.; Blondes, M. S.; Brennan, S.; Corum, M.; Merrill, M. D.



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.



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



Geology of Badlands National Park  

NSDL National Science Digital Library

This page is an introduction to the 75 million years of accumulation and intermittent periods of erosion that has resulted in the Badlands National Park. The history of the Oglicene beds of the Park, one of the world's richest vertebrate fossil sites, is also described. A downloadable PDF that describes the erosion that is responsible for the geology of the Park in more detail is linked to the site.

National Park Service (NPS)


Geological Time Capsule Part I  

NSDL National Science Digital Library

This brief review of Earth history starts with the Archeozoic Period and goes through the Devonian Period. It explains time divisions and that the basic unit of geologic time is the period, which comprises two or more epochs, and that an era consists of two or more periods. The site goes on to explain what was happening in regard to plate tectonics and organic evolution in each of the periods through the Devonian Period.

Oberrecht, Kenn


Geologic mapping using thermal images  

NASA Technical Reports Server (NTRS)

Thermal radiance data from the Heat Capacity Mapping Mission (HCMM) satellite has been used to measure surface reflectance data and to provide additional material composition information through remote sensing. The primary goal was to investigate the utility of HCMM data for geologic applications. Three techniques were used for displaying and combining thermal and visible near infrared (VNIR) data for two desert areas in southern California (Trona and Pisgah): color additive composites (CAC) for day and night IR and day VNIR, principal components, and calculation of thermal inertia images. The HCMM thermal data were more effective than Landsat data in producing separation of compositionally different areas including volcanic and intrusive rocks. The satellite CAC data produced an image for a 1 x 2 degree area, and the color picture was enlarged to a scale of 1:250,000. Playa composition, moisture content, presence of standing water, and vegetation cover were displayed in a variety of colors according to physical characteristics. Areas such as sand dunes were not distinguishable because of the coarse 500-mm HCMM resolution. HCMM thermal data have shown a new dimension to geologic remote sensing, and future satellite missions should allow the continued development of the thermal infrared data for geology.

Abrams, M. J.; Kahle, A. B.; Palluconi, F. D.; Schieldge, J. P.



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.


Global geologic map of Ganymede  

USGS Publications Warehouse

Ganymede is the largest satellite of Jupiter, and its icy surface has been formed through a variety of impact cratering, tectonic, and possibly cryovolcanic processes. The history of Ganymede can be divided into three distinct phases: an early phase dominated by impact cratering and mixing of non-ice materials in the icy crust, a phase in the middle of its history marked by great tectonic upheaval, and a late quiescent phase characterized by a gradual drop in heat flow and further impact cratering. Images of Ganymede suitable for geologic mapping were collected during the flybys of Voyager 1 and Voyager 2 (1979), as well as during the Galileo Mission in orbit around Jupiter (1995–2003). This map represents a synthesis of our understanding of Ganymede geology after the conclusion of the Galileo Mission. We summarize the properties of the imaging dataset used to construct the map, previously published maps of Ganymede, our own mapping rationale, and the geologic history of Ganymede. Additional details on these topics, along with detailed descriptions of the type localities for the material units, may be found in the companion paper to this map (Patterson and others, 2010).

Collins, Geoffrey C.; Patterson, G. Wesley; Head, James W.; Pappalardo, Robert T.; Prockter, Louise M.; Lucchitta, Baerbel K.; Kay, Johnathan P.



Planetary Geology and Geophysics Program  

NASA Technical Reports Server (NTRS)

Geological mapping and topical studies, primarily in the southern Acidalia Planitia/Cydonia Mensae region of Mars is presented. The overall objective was to understand geologic processes and crustal history in the northern lowland in order to assess the probability that an ocean once existed in this region. The major deliverable is a block of 6 1:500,000 scale geologic maps that will be published in 2004 as a single map at 1:1,000,000 scale along with extensive descriptive and interpretive text. A major issue addressed by the mapping was the relative ages of the extensive plains of Acidalia Planitia and the knobs and mesas of Cydonia Mensae. The mapping results clearly favor a younger age for the plains. Topical studies included a preliminary analysis of the very abundant small domes and cones to assess the possibility that their origins could be determined by detailed mapping and remote-sensing analysis. We also tested the validity of putative shorelines by using GIs to co-register full-resolution MOLA altimetry data and Viking images with these shorelines plotted on them. Of the 3 proposed shorelines in this area, one is probably valid, one is definitely not valid, and the third is apparently 2 shorelines closely spaced in elevation. Publications supported entirely or in part by this grant are included.

McGill, George E.




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



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



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


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


Geology and tectonics of Japanese islands: A review - The key to understanding the geology of Asia  

NASA Astrophysics Data System (ADS)

The age of the major geological units in Japan ranges from Cambrian to Quaternary. Precambrian basement is, however, expected, as the provenance of by detrital clasts of conglomerate, detrital zircons of metamorphic and sedimentary rocks, and as metamorphic rocks intruded by 500 Ma granites. Although rocks of Paleozoic age are not widely distributed, rocks and formations of late Mesozoic to Cenozoic can be found easily throughout Japan. Rocks of Jurassic age occur mainly in the Jurassic accretionary complexes, which comprise the backbone of the Japanese archipelago. The western part of Japan is composed mainly of Cretaceous to Paleogene felsic volcanic and plutonic rocks and accretionary complexes. The eastern part of the country is covered extensively by Neogene sedimentary and volcanic rocks. During the Quaternary, volcanoes erupted in various parts of Japan, and alluvial plains were formed along the coastlines of the Japanese Islands. These geological units are divided by age and origin: i.e. Paleozoic continental margin; Paleozoic island arc; Paleozoic accretionary complexes; Mesozoic to Paleogene accretionary complexes and Cenozoic island arcs. These are further subdivided into the following tectonic units, e.g. Hida; Oki; Unazuki; Hida Gaien; Higo; Hitachi; Kurosegawa; South Kitakami; Nagato-Renge; Nedamo; Akiyoshi; Ultra-Tamba; Suo; Maizuru; Mino-Tamba; Chichibu; Chizu; Ryoke; Sanbagawa and Shimanto belts. The geological history of Japan commenced with the breakup of the Rodinia super continent, at about 750 Ma. At about 500 Ma, the Paleo-Pacific oceanic plate began to be subducted beneath the continental margin of the South China Block. Since then, Proto-Japan has been located on the convergent margin of East Asia for about 500 Ma. In this tectonic setting, the most significant tectonic events recorded in the geology of Japan are subduction-accretion, paired metamorphism, arc volcanism, back-arc spreading and arc-arc collision. The major accretionary complexes in the Japanese Islands are of Permian, Jurassic and Cretaceous-Paleogene age. These accretionary complexes became altered locally to low-temperature and high-pressure metamorphic, or high-temperature and low-pressure metamorphic rocks. Medium-pressure metamorphic rocks are limited to the Unazuki and Higo belts. Major plutonism occurred in Paleozoic, Mesozoic and Cenozoic time. Early Paleozoic Cambrian igneous activity is recorded as granites in the South Kitakami Belt. Late Paleozoic igneous activity is recognized in the Hida Belt. During Cretaceous to Paleogene time, extensive igneous activity occurred in Japan. The youngest granite in Japan is the Takidani Granite intruded at about 1-2 Ma. During Cenozoic time, the most important geologic events are back-arc opening and arc-arc collision. The major back-arc basins are the Sea of Japan and the Shikoku and Chishima basins. Arc-arc collision occurred between the Honshu and Izu-Bonin arcs, and the Honshu and Chishima arcs.

Wakita, Koji



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



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



Magnetic effects of hydrothermal alteration in porphyry copper and iron-oxide copper-gold systems: A review  

NASA Astrophysics Data System (ADS)

Magnetic anomaly patterns can be used as a tool for mapping lithology, metamorphic zones and hydrothermal alteration systems, as well as identifying structures that may control passage of magmas or hydrothermal fluids associated with mineralisation. Reliable geological interpretation of mineralised systems requires an understanding of the magmatic, metamorphic and hydrothermal processes that create, alter and destroy magnetic minerals in rocks. Predictive magnetic exploration models for porphyry copper and iron oxide copper-gold (IOCG) deposits can be derived from standard geological models by integrating magnetic petrological principles with petrophysical data, deposit descriptions, and modelling of observed magnetic signatures of these deposits. Even within a particular geological province, the magnetic signatures of similar deposits may differ substantially, due to differences in the local geological setting. Searching for “look-alike” signatures of a known deposit is likely to be unrewarding unless pertinent geological factors are taken into account. These factors include the tectonic setting and magma type, composition and disposition of host rocks, depth of emplacement and post-emplacement erosion level, depth of burial beneath younger cover, post-emplacement faulting and tilting, remanence effects contingent on ages of intrusion and alteration, and metamorphism. Because the effects of these factors on magnetic signatures are reasonably well understood, theoretical magnetic signatures appropriate for the local geological environment can qualitatively guide exploration and make semiquantitative predictions of anomaly amplitudes and patterns. The predictive models also allow detectability of deposit signatures to be assessed, for example when deposits are buried beneath a considerable thickness of nonmagnetic overburden, are covered by highly magnetic heterogeneous volcanic rocks, or there is a strong regional magnetic gradient. This paper reviews the effects of hydrothermal alteration on magnetic properties and magnetic signatures of porphyry copper and iron oxide copper-gold systems and presents examples of predictive magnetic exploration models, and their predicted signatures, in various geological circumstances.

Clark, David A.



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.

International Working Group on Medical Geology


Solid state diffusion during nuclear glass residual alteration in solution  

NASA Astrophysics Data System (ADS)

The long term alteration rate of the French R7T7 nuclear glass has been investigated since many years because this glass has been selected as radionuclide containment matrix in France. Recent studies have shown that this rate remains constant or is slightly decreasing with time. It never reaches zero. Although this long term rate is very low, only 5 nm per year at 323 K in initially pure water, it would be the dominant alteration phenomenon in a geological repository. Two mechanisms are suggested for explaining this long term behaviour: diffusion towards solution of elements from glass through an amorphous altered layer and precipitation of neoformed phases. Former studies showed that diffusion rates are in agreement with a solid state diffusion mechanism. Additional experiments in initially saturated silica water were performed in order to study the impact of various parameters on the values of the diffusion coefficient for mobile chemical elements: pH, temperature, ionic strength and S/ V ratio (glass surface area S to the solution volume V). The solutions and element profiles in altered glass were analysed by ICP-AES and TOF-SIMS, respectively. The results point out that S/ V and ionic strength are not key-parameters. pH leads to significant diffusion coefficient decrease at 323 K when it rises from 8 to 10. Variations with temperature can be modelled with an Arrhenius law. The calculated value of activation energy is discussed in comparison with literature data.

Chave, T.; Frugier, P.; Ayral, A.; Gin, S.



Thematic Conference on Geologic Remote Sensing, 8th, Denver, CO, Apr. 29-May 2, 1991, Proceedings. Vols. 1 & 2  

NASA Technical Reports Server (NTRS)

The proceedings contain papers discussing the state-of-the-art exploration, engineering, and environmental applications of geologic remote sensing, along with the research and development activities aimed at increasing the future capabilities of this technology. The following topics are addressed: spectral geology, U.S. and international hydrocarbon exporation, radar and thermal infrared remote sensing, engineering geology and hydrogeology, mineral exploration, remote sensing for marine and environmental applications, image processing and analysis, geobotanical remote sensing, and data integration and geographic information systems. Particular attention is given to spectral alteration mapping with imaging spectrometers, mapping the coastal plain of the Congo with airborne digital radar, applications of remote sensing techniques to the assessment of dam safety, remote sensing of ferric iron minerals as guides for gold exploration, principal component analysis for alteration mappping, and the application of remote sensing techniques for gold prospecting in the north Fujian province.



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.



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.



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.



Objective Subsurface Geological Modeling using Geological Columns - A case study for the Kisarazu Distinct, Japan  

NASA Astrophysics Data System (ADS)

Geological models of subsurface structure play an important role in disaster assessment, environmental preservation, and underground utilization. These models are often constructed subjectively based on geological data obtained from field survey. However, reliability of subjective model depends on modeler's knowledge and experience as well as on quality of basic data. In order to ensure a more stable reliability of the model, objective approach is necessary. The purpose of this study is to establish an objective geological modeling method. For the purpose of this study, we constructed a subsurface geological model focusing on mathematical treatment of stratigraphy. Study area is the Kisarazu distinct, in the middle part of Chiba Prefecture, Japan. Basic data for modeling are 44 geological columns. In the modeling, firstly, we constructed a Logical Model of Geological Structure (LMGS) that defines a positional relation between geological boundary surfaces and geological units. The LMGS is objectively given by recurrence formula derived from a sequence of geological events arranged in chronological order. Secondly, we generated Digital Elevation Models (DEMs) of geological boundary surfaces using geological columns. Thirdly, we constructed an objective geological model using the LMGS and the DEMs. Finally, we visualized the model in 2D and 3D using GRASS GIS. As a result, in the areas with high number of geological columns, geological map and geological cross-sections derived from objective model were in good agreement with the ones derived from subjective model reported in other studies. In the areas with low number of geological columns, the objective map and cross-sections were somewhat different from subjective ones. In conclusion, the results indicate that objective model may give new findings about subsurface structure. In addition, the objective model gives a more stable reliability than the subjective model because the former ensures traceability of modeling procedures. The LMGS is unfit for complicated geological structures like lens. For the solution of this problem, we need to improve theoretical base of the LMGS.

Nonogaki, S.; Nakazawa, T.



Completeness of the geological record  

NASA Technical Reports Server (NTRS)

The completeness of a sedimentary section of known timespan may be assessed qualitatively by comparing its thickness with the average accumulation for that timespan. Average accumulations may be estimated from sediment volume and continental area data. Quantitative completeness estimation methods based on data compiled from the geological literature have been proposed, but we argue that the literature data are significantly biased and cannot support such methods. Interestingly, however, a comparison of the literature data and accumulation averages computed from sediment volume data suggests that the thickest known sections may be extremely complete.

McShea, D. W.; Raup, D. M.



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.

Stacey Cochiara


Applications of ISES for geology  

NASA Technical Reports Server (NTRS)

The principal applications for onboard data processing and real-time data transmission in the geological sciences are the detection of early warning signs of potential catastrophic events and the rapid assessment of impact and damage following major events. Also, the opportunity for quick look and supporting data during field investigations should not be disregarded. The Eos platforms are ideal for these applications because of the variety of earth sensing instruments and their differing modes of operation. Further study is required to define the role for each instrument and to assess how they can aid each other in establishing an improved output product.

Bowker, David E.



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.


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.



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.


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.


Introduction: The geologic mapping of Vesta  

NASA Astrophysics Data System (ADS)

The purpose of this paper is to introduce the Geologic Mapping of Vesta Special Issue/Section of Icarus, which includes several papers containing geologic maps of the surface of Vesta made to support data analysis conducted by the Dawn Science Team during the Vesta Encounter (July 2011-September 2012). In this paper we briefly discuss pre-Dawn knowledge of Vesta, provide the goals of our geologic mapping campaign, discuss the methodologies and materials used for geologic mapping, review the global geologic context of Vesta, discuss the challenges of mapping the geology of Vesta as a small airless body, and describe the content of the papers in this Special Issue/Section. We conclude with a discussion of lessons learned from our quadrangle-based mapping effort and provide recommendations for conducting mapping campaigns as part of planetary spacecraft nominal missions.

Williams, David A.; Yingst, R. Aileen; Garry, W. Brent



Subsurface geological and geophysical study of the Cerro Prieto geothermal field, Baja California, Mexico  

SciTech Connect

The subsurface investigation of the Cerro Prieto field and surrounding area is described including the stratigraphy, structure, hydrothermal alteration, and reservoir properties for use in designing reservoir simulation models and planning development of the field. Insights into the depositional, tectonic, and thermal history of the area are presented. The following types of data were used: well sample descriptions and analyses, well logs, geophysical surveys; physiography, and regional geology. (MHR)

Lyons, D.J.; van de Kamp, P.C.



The Geologic History of Cape Cod, Massachusetts  

NSDL National Science Digital Library

Geologists are interested in Cape Cod, Massachusetts because it formed by glaciers very recently in terms of geologic time, and because of the ever-changing shore as the Cape adjusts to the rising sea. This United States Geological Survey (USGS) report covers the geologic history of the Cape, which includes glacial retreat, fossils, erosion, and the future of this area. Selected readings are given for further reference.

Robert Oldale


Geology Fieldnotes: Capitol Reef National Park, Utah  

NSDL National Science Digital Library

This Capitol Reef National Park site contains park geology information, park maps, photographs, visitor information, and a teacher feature (resources for teaching geology with National Park examples). Geologic data includes descriptions of the Waterpocket Fold, a monocline formed in the Laramide Orogeny and made of sedimentary rock. Also covered is erosion, and details about the Cathedral Valley outcrop of gypsum. This formation is Permian to Cretaceous in age (270-80 million years old).


Digital geologic map of Beaver County, Oklahoma  

USGS Publications Warehouse

This data set consists of digital data and accompanying documentation for the surficial geology of Beaver County, Oklahoma. The original data are from the Hydrogeologic Map, sheet 1 of 3, included in the U.S. Geological Survey publication, Reconnaissance of the Water Resources of Beaver County, Oklahoma, Hydrologic Investigations Atlas HA-450, Morton and Goemaat, 1973. The geology was compiled by S.L. Schoff, 1953.

Cederstrand, J.R.



Geologic and structural map of eastern Asia  

Microsoft Academic Search

A synthesis of the onshore and offshore geologic data of eastern Asia, prepared by the Institut Francais du Petrole (IFP), has allowed the construction of geologic and structural maps for this region. These maps include three color sheets (scale = 1:2.5 million) and three plates of geologic and structural cross sections. Located between lat. 4° and 35°N, and long. 106°

J. Letouzey; L. Sage




E-print Network

geologists * To produce realistic earth models to support quantitative, predictive computer simulations and petrography Structural geology GIS Intro to everything else (Paleontology, Mineralogy, Potential

Militzer, Burkhard


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.


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.


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.


California Geological Survey-Educational Resources Center  

NSDL National Science Digital Library

How do we understand the Earth and its complexity? It's a crucial question in our age. Fortunately, the California Geological Survey is interested in these matters. The Survey's Educational Resources Center site features California geology maps, teachers' aids, and "California Geology 101." This last resource is an interactive index of online geologic field trip guides and related sites. The resources include an exploration of the 1906 San Francisco Earthquake, replies to questions posed by the "Earthquake DOC," and a glossary of rock and mineral terminology. The maps should not be missed either, as they include a fault activity map of California and a detailed map of the Golden State's geomorphic provinces.



Optimum Transfer Guide: Geology Why Study Geosciences?  

E-print Network

geog- raphy, environmental studies, structural geology & plate tectonics, vertebrate/ invertebrate the environment, environmental quality and air pollution, global climate change, factors impacting water resources

Gelfond, Michael


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.


Investigating SE MN Geology including rock layers, fossils, and Karst geology through Quarry Hill Nature Center  

NSDL National Science Digital Library

This activity is a field investigation where students will increase their knowledge of SE MN geology including rock layers, fossils, and Karst topography. They will also learn how Karst Geology impacts our water quality.



E-print Network

GEO 4510 ­ FIELD GEOLOGY (SUMMER FIELD CAMP), 2014 ­ Project 1 GEOLOGY OF PAROWAN GAP, UTAH of the Hurricane fault), which mark the western boundary of the Colorado Plateau in this region. We will camp

Johnson, Cari


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.



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


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....



Visible Geology: an interactive visualization program for creating and exploring geologic block models  

NSDL National Science Digital Library

Visible Geology is an interactive visualization program where you can create and explore your own geologic block models. The goal of the program is to allow a learning environment that, with the focus of a teacher, provides students with a moment of geologic discovery.

Rowan Cockett


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.



References on Kaolin U.S. Geological Survey  

E-print Network

: Robert L. Virta James R. Herring U.S. Geological Survey U.S. Geological Survey 983 National Center BoxReferences on Kaolin U.S. Geological Survey: Clay and Shale. U.S. Geological Survey (U.S. Bureau: U.S. Geological Survey Open File Report 79-526, 41 p. Cofer, H. E., Jr., Wright, N. A., Carey, M. A


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


Earth magmatic-seawater hydrothermal alteration revealed through satellite-borne Hyperion imagery at Panorama, Western Australia  

Microsoft Academic Search

Hyperion hyperspectral VNIR-SWIR satellite imagery were evaluated for mapping hydrothermal alteration mineralogy associated with Archaean magmatic-seawater convective cells at Panorama, Pilbara Block, Western Australia. The Panorama geology is well exposed in cross section over a 30 km strike length revealing the complete geometry of the hydrothermal system. The hydrothermal discharge sites developed economic sulphide mineralisation as well as early life.

T. J. Cudahy; P. S. Barry



Multisource geological data mining and its utilization of uranium resources exploration  

NASA Astrophysics Data System (ADS)

Nuclear energy as one of clear energy sources takes important role in economic development in CHINA, and according to the national long term development strategy, many more nuclear powers will be built in next few years, so it is a great challenge for uranium resources exploration. Research and practice on mineral exploration demonstrates that utilizing the modern Earth Observe System (EOS) technology and developing new multi-source geological data mining methods are effective approaches to uranium deposits prospecting. Based on data mining and knowledge discovery technology, this paper uses multi-source geological data to character electromagnetic spectral, geophysical and spatial information of uranium mineralization factors, and provides the technical support for uranium prospecting integrating with field remote sensing geological survey. Multi-source geological data used in this paper include satellite hyperspectral image (Hyperion), high spatial resolution remote sensing data, uranium geological information, airborne radiometric data, aeromagnetic and gravity data, and related data mining methods have been developed, such as data fusion of optical data and Radarsat image, information integration of remote sensing and geophysical data, and so on. Based on above approaches, the multi-geoscience information of uranium mineralization factors including complex polystage rock mass, mineralization controlling faults and hydrothermal alterations have been identified, the metallogenic potential of uranium has been evaluated, and some predicting areas have been located.

Zhang, Jie-lin



Mars exploration rover geologic traverse by the spirit rover in the plains of Gusev crater, Mars  

USGS Publications Warehouse

The Spirit rover completed a 2.5 km traverse across gently sloping plains on the floor of Gusev crater from its location on the outer rim of Bonneville crater to the lower slopes of the Columbia Hills, Mars. Using the Athena suite of instruments in a transect approach, a systematic series of overlapping panoramic mosaics, remote sensing observations, surface analyses, and trenching operations documented the lateral variations in landforms, geologic materials, and chemistry of the surface throughout the traverse, demonstrating the ability to apply the techniques of field geology by remote rover operations. Textures and shapes of rocks within the plains are consistent with derivation from impact excavation and mixing of the upper few meters of basaltic lavas. The contact between surrounding plains and crater ejecta is generally abrupt and marked by increases in clast abundance and decimeter-scale steps in relief. Basaltic materials of the plains overlie less indurated and more altered rock types at a time-stratigraphic contact between the plains and Columbia Hills that occurs over a distance of one to two meters. This implies that regional geologic contacts are well preserved and that Earth-like field geologic mapping will be possible on Mars despite eons of overturn by small impacts. ?? 2005 Geological Society of America.

Crumpler, L.S.; Squyres, S.W.; Arvidson, R.E.; Bell, J.F.; Blaney, D.; Cabrol, N.A.; Christensen, P.R.; DesMarais, D.J.; Farmer, J.D.; Fergason, R.; Golombek, M.P.; Grant, F.D.; Grant, J.A.; Greeley, R.; Hahn, B.; Herkenhoff, K.E.; Hurowitz, J.A.; Knudson, A.T.; Landis, G.A.; Li, R.; Maki, J.; McSween, H.Y.; Ming, D.W.; Moersch, J.E.; Payne, M.C.; Rice, J.W.; Richter, L.; Ruff, S.W.; Sims, M.; Thompson, S.D.; Tosca, N.; Wang, A.; Whelley, P.; Wright, S.P.; Wyatt, M.B.



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.



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.



The Mekong at climatic crossroads: Lessons from the geological past.  


The wetlands of the lower Mekong River Basin are ecologically and socioeconomically significant, but they are threatened by predicted climatic change. The likely response of wetland ecosystems to altered flooding regimes and surface-water chemistry is unknown in detail and difficult to model. One way of exploring the impact of climate change on wetland ecosystems is to utilize proxy environmental data that reveal patterns of change over geological time. In recent years, the coverage and resolution of proxy climatic data have improved markedly in the region. Recent evidence of the South China Sea transgression into southern and central Cambodia and paleobotanical evidence from the Tonle Sap ("Great Lake") and elsewhere allow us to explore how periods of higher-than-present sea level and increased monsoon rainfall in the past have impacted the wetland ecology of the lower Mekong River Basin. PMID:18595270

Penny, Dan



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)



Lessons from Natural Analog Studies for Geologic Disposal of High-Level Nuclear Waste (Invited)  

NASA Astrophysics Data System (ADS)

For over fifty years natural analog studies have provided lessons addressing scientific, technical, and social problems concerning geologic disposal of high-level nuclear waste. Idealized concepts for permanent disposal environments evolved from an understanding of the geological, geochemical and hydrological characteristics of analogous rocks including natural salt deposits (as advocated by the US National Academy of Sciences in 1957), ancient cratonic rocks (as investigated at Lac du Bonnet, Canada, Aspö, Sweden, and Vienne, France), and marine sedimentary rock formations (as studied at Mol, Belgium, and Bure, France). Additional multidisciplinary studies have been conducted at natural sites that bear characteristics analogous to potential repository systems, notably at natural uranium (and thorium) deposits including Poços de Caldas, Brazil, Alligator Rivers, Australia, Peña Blanca, Mexico, and Oklo, Gabon. Researchers of natural analogs for geologic disposal have addressed technical uncertainties regarding processes that have transpired over large time and space scales, which are generally inaccessible to laboratory studies. Principal questions for nuclear waste disposal include the geochemical stability and alteration rates of radionuclide bearing minerals and the mechanisms and rates of transport of radionuclides in groundwater. In their most direct applications, natural analogs studies have been devoted to testing specific models for repository performance and the experimental data that support those models. Parameters used in predictive performance assessment modeling have been compared to natural system data, including mineral solubilities, sorption coefficients, diffusion rates, and colloid transport properties. For example, the rate of uraninite oxidation and the natural paragenesis of uranium mineral alteration at Peña Blanca have been compared favorably to results of experimental studies of spent fuel alteration related to the proposed repository at Yucca Mountain, Nevada, USA. These results generally bracket repository conditions between natural and experimental systems providing confidence in the understanding of expected processes. Also, the conceptual bases and numerical techniques for modeling unsaturated zone contaminant transport over periods of thousands of years at Yucca Mountain were tested by modeling the observable record of metal transport from archaeological artifacts buried in Holocene tuff at Akrotiri, Greece. Geologically episodic mineral alteration and contaminant transport have been documented using radioisotope data in numerous analog systems providing insights for the interpretation and validity of predictive models for long term repository performance. The applicability and value of natural analog studies to understanding geologic disposal systems is a persistent question. As proposed disposal sites become increasingly well defined by site characterization and engineering design, the strengths and weaknesses of analogies can be assessed. Confidence in predictive models for complex geologic and engineered phenomena can be enhanced through multiple lines of investigation including studies of natural analog systems.

Murphy, W. M.



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.



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.


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.

University of Utah's Yellowstone Geophysics Research Group



E-print Network


McKay, Brendan


Geology highlights for Ride the Rockies 2010  

USGS Publications Warehouse

The author provides a brief description of the geology along the route for each day of the ride, from June 13 through June 19, 2010. Ride the Rockies begins in Grand Junction, with stops in Delta, Ouray, Durango, Pagosa Springs, Alamosa, and ends in Salida, Colorado. A small, generalized geologic map also is shown.

Slate, J.L.; Hess, Amber; Van Sistine, D.R.



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


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.



Marine Geology: Research Beneath the Sea  

NSDL National Science Digital Library

This report by the United States Geological Survey (USGS) details the history of marine geology. The scope of this field, tools and equipment used, and methods of study are covered. The report also discusses resource potential of the marine environment, plate tectonics, the effects of marine processes, and new frontiers intended to expand our understanding of the oceans.


The urban geology of Darwin, Australia  

Microsoft Academic Search

Darwin, on the north coast of the Australian mainland lies only 12° south of