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Articles 61 - 90 of 102

Full-Text Articles in Stratigraphy

Organic Chemostratigraphic Markers Characteristic Of The (Informally Designated) Anthropocene Epoch, Michael A. Kruge Dec 2008

Organic Chemostratigraphic Markers Characteristic Of The (Informally Designated) Anthropocene Epoch, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Recognizing the tremendous collective impact of humans on the environment in the industrial age, the proposed designation of the current time period as the Anthropocene Epoch has considerable merit. One of the signature activities during this time continues to be the intensive extraction, processing, and combustion of fossil fuels. While fossil fuels themselves are naturally-occurring, they are most often millions of years old and associated with deeply buried strata. They may be found at the surface, for example, as natural oil seeps or coal seam outcrops, but these are relatively rare occurrences. Fossil fuels and their myriad by-products become the …


Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton Jan 2008

Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surficial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.


Sulfur Geochemistry And Diagenesis In A Gas Hydrate Terrane, Cascadia Margin, Offshore Oregon: Role Of Anaerobic Methane Oxidation, David Deigert, Walter S. Borowski Mar 2007

Sulfur Geochemistry And Diagenesis In A Gas Hydrate Terrane, Cascadia Margin, Offshore Oregon: Role Of Anaerobic Methane Oxidation, David Deigert, Walter S. Borowski

EKU Faculty and Staff Scholarship

We present sulfide mineral data from south Hydrate Ridge located in a gas hydrate terrane, offshore Oregon. Sulfide sulfur concentration and the isotopic composition of sulfur (d34S) in authigenic sulfide minerals are analyzed from sediment samples collected on Ocean Drilling Project (ODP) Leg 204. Shallow sediment samples (<25 >mbsf) assess the relative importance of anaerobic methane oxidation (AMO) as a biogeochemical process, both here and at the Blake Ridge, another well known gas hydrate terrane offshore southeastern United States. Deep samples (>25 mbsf) are used to evaluate sulfur diagenesis and its controls from early Pleistocene to the …


A Preliminary Study Of Sulfide Mineral Formation In Methane-Rich, Marine Sediments Associated With Anaerobic Methane Oxidation, Cascadia Continental Margin, Offshore Oregon, David Deigert, Walter S. Borowski Nov 2006

A Preliminary Study Of Sulfide Mineral Formation In Methane-Rich, Marine Sediments Associated With Anaerobic Methane Oxidation, Cascadia Continental Margin, Offshore Oregon, David Deigert, Walter S. Borowski

EKU Faculty and Staff Scholarship

Within gas hydrate settings, sulfide mineralization in marine sediments is likely controlled by two microbially-mediated, sulfate-depleting processes: anaerobic methane oxidation (AMO) and sulfate reduction. If large amounts of methane are delivered to the sulfate-methane interface (SMI), predominantly by diffusion, larger amounts of solid sulfide sulfur should occur there as dissolved sulfide combines with iron, forming an authigenic precipitate. We measure the amount of diagenetic sulfide sulfur at three locations in the Hydrate Ridge vicinity by extracting the bulk sedimentary sulfide-phase minerals (So, FeS, and FeS2) through chromium reduction, precipitating sulfide sulfur as silver sulfide, and gravimetrically …


A Preliminary Comparison Of The Sulfur Geochemistry Between Two Gas Hydrate Terranes, Michael D. Spicer, Walter S. Borowski Mar 2006

A Preliminary Comparison Of The Sulfur Geochemistry Between Two Gas Hydrate Terranes, Michael D. Spicer, Walter S. Borowski

EKU Faculty and Staff Scholarship

We compare the authigenic sulfide mineral geochemistry of two, different gas hydrate terranes: the accretionary wedge of the Cascadia continental margin (offshore Oregon) and the passive margin of the Blake Ridge region (offshore southeastern US). We expect diagenetic processes effecting sulfide mineral formation (elemental sulfur, iron monosulfides, and pyrite) within these sediments to respond to differing geologic conditions at each setting. In both settings, methane diffuses upward from gas hydrates to the methane-sulfate interface (SMI), where it is consumed by reaction with sulfate during anaerobic methane oxidation (AMO). This microbially-mediated, diagenetic process produces an interstitial environment conducive to authigenic sulfide …


Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee Jan 2006

Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee

ANDRILL Project Information

Purpose of This Document

This document is a guide to participation for science team members involved in the McMurdo Ice Shelf (MIS) Project of the ANDRILL Program. The document provides the following information: 1) An overview of the ANtarctic geologic DRILLing (ANDRILL) Program; 2) An overview of expected individual involvement in and commitment to the MIS Project; and 3) Logistical information most relevant to on-ice participants. Information provided in this document will be supplemented by the publication of the MIS Science and Logistics Implementation Plan (SLIP).The SLIP will be available to all MIS ANDRILL participants prior to commencement of drilling. …


Scientific Logistics Implementation Plan For The Andrill Mcmurdo Ice Shelf Project, Timothy R. Naish, Richard H. Levy, Ross D. Powell, Mis Science And Operations Team Members Jan 2006

Scientific Logistics Implementation Plan For The Andrill Mcmurdo Ice Shelf Project, Timothy R. Naish, Richard H. Levy, Ross D. Powell, Mis Science And Operations Team Members

ANDRILL Project Information

Summary

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8°C by the end of the century is unknown. Models on which predictions are based need to be constrained by geological proxy data from the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than …


Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry Jan 2006

Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry

Geology Theses and Dissertations

Northward transport of the Yakutat terrane along the Transition and Queen Charlotte-Fairweather transform faults led to Neogene collision of the Yakutat terrane with the southern continental Alaska margin. Northward translation resulted in a stratigraphy that records the erosion of thermotectonic terranes along its path. The strata of the Yakutat terrane includes the Lower Oligocene to Lower Eocene Kulthieth Formation, the Upper Eocene to Lower Miocene Poul Creek Formation and the Miocene-Pleistocene Yakataga Formation. Detrital zircon fission-track (DZFT) ages from stratigraphically coordinated samples collected in the Northern Robinson Mountains yield provenance information of the units that can shed light on their …


Andrill Mcmurdo Ice Shelf Project Scientific Prospectus, Timothy R. Naish, Ross D. Powell, Peter J. Barrett, Huw Horgan, Gavin B. Dunbar, Gary S. Wilson, Richard Levy, Natalie Robinson, L. Carter, Alex R. Pyne, Frank Niessen, Stephen Bannister, Natalie Balfour, Detlef Damaske, Stuart Henrys, Phil Kyke, Terry Wilson Jun 2005

Andrill Mcmurdo Ice Shelf Project Scientific Prospectus, Timothy R. Naish, Ross D. Powell, Peter J. Barrett, Huw Horgan, Gavin B. Dunbar, Gary S. Wilson, Richard Levy, Natalie Robinson, L. Carter, Alex R. Pyne, Frank Niessen, Stephen Bannister, Natalie Balfour, Detlef Damaske, Stuart Henrys, Phil Kyke, Terry Wilson

ANDRILL Project Information

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8!C by the end of the century is not known. Models on which predictions are based need to be constrained by geological data of the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than today. …


Andrill Southern Mcmurdo Sound Project Scientific Prospectus, David M. Harwood, Fabio Florindo, Richard H. Levy, Christopher R. Fielding, Stephen F. Pekar, M. A. Speece, Sms Science Team, Andrill Science Management Office May 2005

Andrill Southern Mcmurdo Sound Project Scientific Prospectus, David M. Harwood, Fabio Florindo, Richard H. Levy, Christopher R. Fielding, Stephen F. Pekar, M. A. Speece, Sms Science Team, Andrill Science Management Office

ANDRILL Project Information

During the austral summer of 2007 the ANtarctic DRILLing program (ANDRILL) will drill from a sea-ice platform in southern McMurdo Sound to obtain new information about the Neogene Antarctic cryosphere and evolution of Antarctic rift basins.


Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii Apr 2005

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d34 S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the effect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern United States) by extracting total sedimentary sulfide using chromium reduction. We use …


Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii Mar 2004

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d34 S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the effect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern United States) by extracting total sedimentary sulfide using chromium reduction. We use …


Changes In Sulfur Concentration And Sulfur Isotopic Composition Within Authigenic Sulfide Minerals From Sediments Of Miocene Age To The Present, Odp Site 995, Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski Mar 2004

Changes In Sulfur Concentration And Sulfur Isotopic Composition Within Authigenic Sulfide Minerals From Sediments Of Miocene Age To The Present, Odp Site 995, Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski

EKU Faculty and Staff Scholarship

The Blake Ridge area (offshore southeastern United States) consists of deep-water continental margin sediments overlying deposits of methane gas hydrate. Authigenic sulfide minerals (elemental sulfur, S˚; iron monosulfides, ~FeS; and pyrite, FeS2) are actively deposited in these sediments due to sulfate reduction and focused anaerobic methane oxidation (AMO) at the sulfate-methane interface (SMI). Sulfide minerals at the present SMI are enriched in 34S relative to those produced by sulfate reduction of organic matter higher in the sulfate reduction zone. 34S enrichments preserved in the sediment column may identify relatively high amounts of AMO and thus record …


Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii Nov 2003

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d34S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the affect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern North America) by extracting total sedimentary sulfide using chromium reduction. We use …


Enrichments Of 34s In Sulfide Minerals Of Deep-Water Marine Sediments Of The Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski Mar 2003

Enrichments Of 34s In Sulfide Minerals Of Deep-Water Marine Sediments Of The Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski

EKU Faculty and Staff Scholarship

Past research shows that active sulfide mineralization occurs at the base of the sulfate reduction zone (SRZ) in modern, deep-water, continental-margin sediments that overlie methane gas hydrate. These sulfide minerals (elemental sulfur, Sº; iron monosulfides, ~FeS; and pyrite, FeS2) are enriched in 34S because of sulfate reduction and anaerobic methane oxidation (AMO) processes occurring above and near the sulfate-methane interface (SMI).

The data in this study show that 5 discrete zones of sulfide minerals are preserved in a 703.8-meter sediment column associated with methane gas hydrate. These zones of sulfide minerals are also enriched in 34S. …


Organic Geochemical Analysis Of Late-Glacial And Early-Holocene Ecosystem Changes: A Case Study From Northern New England Lakes, Michael A. Kruge, Andrea Lini Jun 2002

Organic Geochemical Analysis Of Late-Glacial And Early-Holocene Ecosystem Changes: A Case Study From Northern New England Lakes, Michael A. Kruge, Andrea Lini

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The lacustrine sedimentary archive of organic remains provides important evidence for the reconstruction of the environmental histories of lakes and their watersheds, recording the response of the Earth's biota to changes on scales varying from the local to the global. The last Glacial-Interglacial transition presents an opportunity to investigate how, and at what rates, watershed and lake ecosystems were established on once glaciated, carbon and nutrient-poor landscapes. The small lakes of northern Vermont (USA) provide an appropriate setting in which to investigate such changes.

As part of a multidisciplinary study of three Vermont lake sediment cores, samples ranging in age …


From Sand To Sandstone: Documenting The Total Change During Diagenesis, Wilfrido Solano-Acosta Dec 2001

From Sand To Sandstone: Documenting The Total Change During Diagenesis, Wilfrido Solano-Acosta

All-Inclusive List of Electronic Theses and Dissertations

The objective of this study is to provide a more comprehensive picture of sandstone diagenesis from a different perspective; starting from an analog sand serving as a precursor of a lithified sandstone.


A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry Jan 1999

A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The nature of the contribution of the various types of algae to sedimentary organic matter continues to be a topic of research interest. Crustose red algae have however received less attention than other types. The fossil calcareous red algae (Rhodophyta) analyzed in this study are two relatively unrecrystallized specimens of Parachaetetes (Family Solenoporacea) from the lower part of the Ste. Genevieve Formation (Carboniferous, Visean) in Union County, Illinois, USA. They occurred in the patch reef phase of a small carbonate mudmound-patchreef. The three modern specimens (collected and identified by F. Collier) are the crustose algae Lithothamnion, Clathromorphum and Phymatolithon …


Chemical Weathering Of Volcanic Ash As A Probable Origin Of Chert In The Reid's Mistake Formation Of The Newcastle Coal Measures, Sydney Basin, Australia, Adil M. Wadia May 1998

Chemical Weathering Of Volcanic Ash As A Probable Origin Of Chert In The Reid's Mistake Formation Of The Newcastle Coal Measures, Sydney Basin, Australia, Adil M. Wadia

All-Inclusive List of Electronic Theses and Dissertations

Chert is normally considered to be marine biogenic in origin. However, chert lenses and nodules in the volcanic ash horizon of the Reid's Mistake Formation at Swansea Head, Newcastle Coal Measures of the Sydney Basin appear to have formed differently. Their mode of occurrence and their close association with paper-thin clay layers within the same volcanic unit suggest that they formed as a result of chemical weathering of volcanic ash. This hypothesis is supported by the data gathered from thin section petrography and x-ray diffraction analyses. Petrographic studies indicate the precipitation of microcrystalline to cryptocrystalline quartz and the dissolution/replacement/alteration of …


Geochemical Characteristics And Correlations Within The Triassic-Jurassic Age Gabbs And Sunrise Formations Of West Central Nevada, Karen Elizabeth Boelling May 1997

Geochemical Characteristics And Correlations Within The Triassic-Jurassic Age Gabbs And Sunrise Formations Of West Central Nevada, Karen Elizabeth Boelling

Dissertations and Theses

Trace and minor element geochemistry was determined using Instrumental Neutron Activation Analysis for ninety-six (96) limestone and calcareous siltstone samples from four stratigraphic sections in the Triassic-Jurassic age Gabbs and Sunrise formations of west central Nevada. Geochemical data support lithologic and faunal interpretations of relative basin positions of the Sunrise Formation stratigraphic sections, as well as basin development (including transgressive­-regressive sequences) during deposition of the Gabbs and Sunrise formations at New York Canyon (Gabbs Valley Range). All sections show characteristics of both oceanic and continental island arc sources. Rare positive Eu anomalies relative to chondrites suggest that the Gabbs Formation …


Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen Apr 1997

Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen

OES Theses and Dissertations

Four molluscan assemblage zones in southern Florida corresponding to the Pinecrest Sand Member of the Tamiami Formation, and the Caloosahatchee, Bermont and Fort Thompson shell beds were identified following quantitative and qualitative analyses of the fossil molluscan fauna. Twenty-eight bulk sediment samples collected from 16 localities across southern Florida were processed for fossil material, and yielded nearly 60,000 specimens belonging to 311 species. A Q-mode cluster analysis compared sediment samples on the basis of 188 species whose abundances had been converted to binary presence-absence form. The cluster analysis was run four times using the Jaccard and Dice similarity coefficients as …


Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi Jan 1997

Comparison Of Source Rock Geochemistry Of Selected Rocks From The Schei Point Group And Ringnes Formation, Sverdrup Basin, Arctic Canada, P. K. Mukhopadhyay, F. Goodarzi, Michael A. Kruge, M. H. Alimi

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Organic-rich from the Schei Point group (middle to late Triassic in age) and the Ringnes formation (late Jurassic) from the Sverdrup basin of the Canadian arctic archipelago have been geochemically evaluated for source rock characterization. Most samples from the Schei Point group are organic-rich (> 2% TOC) and are considered as immature to mature oil-prone source rocks [kerogen types I, I-II (IIA) and II (IIA)]. These kerogen types contain abundant AOM1, AOM2 and alginite (Tasmanales, Nostocopsis, Leiosphaeridia, acritarch and dinoflagellate) with variable amounts of vitrinite, inertinite and exinite. Samples from the Ringnes formation contain dominant vitrinite and inertinite …


Fossil Charcoal In Cretaceous-Tertiary Boundary Strata: Evidence For Catastrophic Firestorm And Megawave, Michael A. Kruge Jan 1994

Fossil Charcoal In Cretaceous-Tertiary Boundary Strata: Evidence For Catastrophic Firestorm And Megawave, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Organic matter separated from calcareous sandstone from the upper portion of a deep-water tsunami deposit at Arroyo el Mimbral, Taumalipas (Mexico), which marks the biostratigraphically-defined Cretaceous-Tertiary boundary, consists primarily of fossil charcoal, including semifusinite and pyrofusinite. Analytical pyrolysis-gas chromatography-mass spectrometry revealed the highly aromatic and polyaromatic character of the organic matter assemblage, typical of the products of partial combustion. The organic matter probably originated as terrestrial vegetation that was caught in a firestorm and subsequently transported far offshore in the backwash of a megawave. These data are consistent with the hypothesis of combustion of large masses of vegetation triggered by …


The Geology Of The Tuff Of Bridge Spring: Southern Nevada And Northwestern Arizona, Shirley Ann Morikawa Dec 1993

The Geology Of The Tuff Of Bridge Spring: Southern Nevada And Northwestern Arizona, Shirley Ann Morikawa

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Tuff of Bridge Spring (TBS) is a regionally-widespread, andesite to rhyolite (59.50 to 74.91 wt. %) ash-flow tuff of mid-Miocene age (ca. 15.2 Ma) that is exposed in the northern Colorado River extensional corridor of southern Nevada and northwestern Arizona. Determination of the areal distribution, geochronology, lithology, geochemistry, and internal stratigraphy of the TBS is important for its establishment as a reliable stratigraphic reference horizon for tectonic reconstructions of the extensional corridor during the middle Miocene. Based on reoccurring patterns of major and trace element variation, the TBS is divided into constant Cr/variable SiO2 and variable Cr/variable SiO …


Organic Geochemistry Of Permian Organic-Rich Sediments From The Sudetes Area, Sw Poland, Shareen R. Yawanarajah, Michael A. Kruge, Maria Mastalerz, Wojciech Sliwinski Jan 1993

Organic Geochemistry Of Permian Organic-Rich Sediments From The Sudetes Area, Sw Poland, Shareen R. Yawanarajah, Michael A. Kruge, Maria Mastalerz, Wojciech Sliwinski

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Lacustrine and marine sediments from the Permian rift-basins of southwestern Poland were analysed using GC-MS and petrographic techniques. High Pr/Ph ratios, gamma- and beta-carotanes and gammacerane in the lacustrine sediments indicate deposition under elevated water salinities. The primary organic matter is represented by bacterial and algal lipids with variable terrestrial input. Marine algal lipids with minor bacterial and cyanobacterial lipids are the primary source of organic matter in the marine sediments. Extended hopanes, n-alkanes with even-odd predominance and low Ts/Tm ratios are consistent with deposition in a closed, evaporitic basin with substantial carbonate sedimentation.


Correlation Of The Tioga Bentonites Using Rhyolitic Melt Inclusions Found In Quartz Phenocrysts As Geochemical Fingerprints, John W. Waechter Jan 1993

Correlation Of The Tioga Bentonites Using Rhyolitic Melt Inclusions Found In Quartz Phenocrysts As Geochemical Fingerprints, John W. Waechter

Geology Theses and Dissertations

The Tioga bentonites were first noted by Fettke in 1931 from well cuttings in the Tioga gas fields of Tioga County, Pennsylvania. They have been used by many investigators (Oliver, 1954, 1956; Dennison, 1963; Dennison and Textoris, 1967, 1978; Epstein, 1986; Smith and Way, 1983; Way et al., 1986) as a time-plane to correlate stratigraphic units from eastern Pennsylvania to Illinois and from southern Ontario to Virginia. The Tioga bentonites are recognized as seven major volcanic ash layers labeled Tioga-A - Tioga-G as well as several minor layers labeled Tioga-A1 - Tioga-A3 (Way et al., 1986). They occur within the …


Biological Markers In Lower Jurassic Synrift Lacustrine Black Shales, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, Jay F. Akes, Paul E. Meriney Jan 1990

Biological Markers In Lower Jurassic Synrift Lacustrine Black Shales, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, Jay F. Akes, Paul E. Meriney

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The East Berlin Formation (Lower Jurassic, Hartford basin, Connecticut, U.S.A.) is distinctive for its six cyclic units of lacustrine black shale and gray mudstone. separated by playa and fluvial redbeds. The black shales arc each about a meter thick and were deposited in subtropical, thermally stratified, oligomictic lakes, the youngest of which (lakes 3 through 6) were large enough to flood most of the basin and attained depths of several tens of meters.

The saturate fractions of solvent extracts of organic-rich black shales from each of the six lakes, collected at fresh roadcuts near East Berlin, arc dominated by extended …


Organic Geochemistry Of A Lower Jurassic Synrift Lacustrine Sequence, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, David F. Bensley, John C. Crelling, R Jay Akes, Paul E. Meriney Jan 1990

Organic Geochemistry Of A Lower Jurassic Synrift Lacustrine Sequence, Hartford Basin, Connecticut, U.S.A., Michael A. Kruge, John F. Hubert, David F. Bensley, John C. Crelling, R Jay Akes, Paul E. Meriney

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Synrift terrestrial strata of the Lower Jurassic East Berlin Formation (Hartford basin, Connecticut, U.S.A.) record cyclical expansion and contraction of major lakes, six of which were deep enough to develop anoxic bottom waters. We have studied one representative lacustrine sequence in detail, sampling a new roadcut near the village of East Berlin. The section examined is 4 m thick, with a gray siltstone at the base, deposited in shallow water, overlain by an organic-rich black shale (deep water), succeeded in turn by another gray siltstone, deposited as the lake waters gradually receded. The upper gray siltstone is chemically distinct from …


Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson May 1988

Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson

Dissertations and Theses

The Dooley Rhyolite Breccia in northeast Oregon was erupted between 12 and 16 million years ago, from central vents and linear feeder dikes within the Dooley Mountain quadrangle. The peraluminous, high-silica rhyolites of the formation were erupted over an irregular highland of eroded pre-Tertiary metamorphic rocks locally overlain by intracanyon, Eocene Clarno-type basalt flow(s). The Dooley Rhyolite Braccia is exposed in a tectonically disrupted, north-south trending graben across the Elkhorn Range. The formation is variable in thickness with maximum thickness exceeding 660 meters in the south and 600 meters in the north half of the quadrangle. Volumetrically the formation is …


Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich Jan 1987

Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich

Geology Theses and Dissertations

Granitic pegmatites associated with the Grenville orogeny intrude a mid-Proterozoic, upper amphibolite to near granulite facies terrane in the southeastern Adirondack Mountains of New York State. The inferred anatectic, fluid-saturated, and minimum melt characteristics of the pegmatites suggest that they can be used as analogs of the "granite" or "haplogranite" system, and as indicators of crustal temperature, pressure, and fluid conditions during a late stage of the Grenville orogeny. Bulk chemical compositions of seven simple, undeformed pegmatites in the southeastern Adirondacks indicate that they are generally depleted in silica and sodium, and enriched in potassium, relative to experimental data on …