Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- University of South Florida (140)
- University of Nebraska - Lincoln (120)
- Old Dominion University (112)
- University of Nevada, Las Vegas (107)
- Montclair State University (55)
-
- University of Texas at El Paso (53)
- University of Arkansas, Fayetteville (49)
- Central Washington University (47)
- University of Kentucky (47)
- Portland State University (42)
- Eastern Kentucky University (40)
- Western Kentucky University (40)
- Louisiana State University (35)
- University of New Mexico (34)
- City University of New York (CUNY) (31)
- Missouri State University (31)
- Western Michigan University (31)
- University at Albany, State University of New York (30)
- Boise State University (23)
- Stephen F. Austin State University (23)
- Missouri University of Science and Technology (21)
- West Virginia University (18)
- Western University (18)
- Southern Methodist University (17)
- University of Southern Maine (17)
- Montana Tech Library (16)
- Dartmouth College (15)
- California Polytechnic State University, San Luis Obispo (12)
- Indiana State University (12)
- Northern Illinois University (12)
- Keyword
-
- Geochemistry (185)
- Geology (53)
- Stable isotopes (34)
- Petrology (31)
- Groundwater (29)
-
- Isotopes (29)
- Earth sciences (25)
- Paleoclimate (21)
- Karst (20)
- Mineralogy (18)
- Sulfide (18)
- Uranium (18)
- Zircon (18)
- Sulfate (17)
- Trace elements (17)
- Water quality (17)
- Hydrogeology (16)
- Climate change (15)
- Economic Geology (15)
- Mars (15)
- Minerals (15)
- Provenance (15)
- Soil (15)
- Gas hydrate (14)
- Geochronology (14)
- Basalt (13)
- Salinity (13)
- Sulfur isotope (13)
- Carbon dioxide (12)
- Carbon sequestration (12)
- Publication
-
- UNLV Theses, Dissertations, Professional Papers, and Capstones (71)
- International Journal of Speleology (62)
- Department of Earth and Environmental Studies Faculty Scholarship and Creative Works (53)
- Open Access Theses & Dissertations (52)
- United States Geological Survey: Publications (52)
-
- USF Tampa Graduate Theses and Dissertations (45)
- EKU Faculty and Staff Scholarship (40)
- Graduate Theses and Dissertations (40)
- OES Theses and Dissertations (40)
- Dissertations and Theses (37)
- OES Faculty Publications (36)
- Theses and Dissertations--Earth and Environmental Sciences (34)
- Graduate Theses/Dissertations (31)
- All Master's Theses (30)
- Earth and Planetary Sciences ETDs (27)
- Electronic Theses and Dissertations (27)
- Masters Theses (25)
- Geology Theses and Dissertations (24)
- Geology Faculty Publications (21)
- Masters Theses & Specialist Projects (21)
- Boise State University Theses and Dissertations (20)
- Earth Sciences Publications (18)
- All Faculty Scholarship for the College of the Sciences (17)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (17)
- LSU Master's Theses (17)
- Maine Collection (17)
- Publications and Research (17)
- LSU Doctoral Dissertations (16)
- Chemistry & Biochemistry Theses & Dissertations (15)
- Graduate Theses & Non-Theses (15)
- Publication Type
Articles 1231 - 1260 of 1546
Full-Text Articles in Earth Sciences
Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer
Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer
United States Geological Survey: Staff Publications
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L-1 and MeHg was less than 0.2 ng L-1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with …
Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das
Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das
Dissertations
Metal oxy-hydroxides and phyllosilicate minerals play a significant role in the fate and transport of heavy metals in the environment (Bertsch and Seaman, 1999). Chemical speciation of metals affects their bioavailability and chemical reactivity (Stumm and Morgan, 1996). Surface complexation models (SCMs) based on equilibrium thermodynamic principles have been successfully used to quantify adsorption of heavy metals on pure solid minerals, including phyllosilicates and oxy-hydroxides. For natural sediments with mixed mineralogy, Davis et al. (1998) suggested two different SCM approaches, namely, the component additivity and generalized composite models. In this study, adsorption of lead on pure HFO, silica and kaolinite …
Energy-Constrained Recharge, Assimilation, And Fractional Crystallization (Ec-Raxfc): A Visual Basic Computer Code For Calculating Trace Element And Isotope Variations Of Opensystem Magmatic Systems, Wendy A. Bohrson, Frank J. Spera
Energy-Constrained Recharge, Assimilation, And Fractional Crystallization (Ec-Raxfc): A Visual Basic Computer Code For Calculating Trace Element And Isotope Variations Of Opensystem Magmatic Systems, Wendy A. Bohrson, Frank J. Spera
All Faculty Scholarship for the College of the Sciences
Volcanic and plutonic rocks provide abundant evidence for complex processes that occur in magma storage and transport systems. The fingerprint of these processes, which include fractional crystallization, assimilation, and magma recharge, is captured in petrologic and geochemical characteristics of suites of cogenetic rocks. Quantitatively evaluating the relative contributions of each process requires integration of mass, species, and energy constraints, applied in a self-consistent way. The energy-constrained model Energy-Constrained Recharge, Assimilation, and Fractional Crystallization (EC-RaxFC) tracks the trace element and isotopic evolution of a magmatic system (melt + solids) undergoing simultaneous fractional crystallization, recharge, and assimilation. Mass, thermal, and compositional (trace …
Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology
Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology
Earth, Environmental, and Atmospheric Sciences Publications
No abstract provided.
Shallow Slab Fluid Release Across And Along The Mariana Arc-Basin System: Insights From Geochemistry Of Serpentinized Peridotites From The Mariana Fore Arc, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Patricia Fryer
Shallow Slab Fluid Release Across And Along The Mariana Arc-Basin System: Insights From Geochemistry Of Serpentinized Peridotites From The Mariana Fore Arc, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Patricia Fryer
Geology Faculty Publications
Shallow slab devolatilization is not only witnessed through fluid expulsion at accretionary prisms, but is also evidenced by active serpentinite seamounts in the shallow fore-arc region of the Mariana convergent margin. Ocean Drilling Program (ODP) Leg 195 recovered serpentinized peridotites that present a unique opportunity to study the products of shallow level exchanges between the upper mantle and slab-derived fluids. Similar to samples recovered during ODP Leg 125, the protoliths of these fore-arc serpentinized peridotites are mantle harzburgites that have suffered large volume melt extraction (up to 25%) prior to interactions with fluids released from the downgoing Pacific Plate. Samples …
Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler
Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler
All Faculty Scholarship for the College of the Sciences
Combined petrographic, structural and geochronological study of the Malashan dome, one of the North Himalayan gneiss domes, reveals that it is cored by a Miocene granite, the Malashan granite, that intruded into the Jurassic sedimentary rocks of Tethys Himalaya. Two other granites in the area are referred to as the Paiku and Cuobu granites. New zircon SHRIMP U-Pb and muscovite and biotite 40Ar-39Ar dating show that the Paiku granite was emplaced during 22.2–16.2 Ma (average 19.3 ± 3.9 Ma) and cooled rapidly to 350–400 °C at around 15.9 Ma. Whole-rock granite chemistry suggests the original granitic magma …
Organic Geochemical Investigation Of A Highly Contaminated Urban Waterway: The Gowanus Canal, Brooklyn, New York, Usa, Michael A. Kruge, Kevin K. Olsen, Eric A. Stern
Organic Geochemical Investigation Of A Highly Contaminated Urban Waterway: The Gowanus Canal, Brooklyn, New York, Usa, Michael A. Kruge, Kevin K. Olsen, Eric A. Stern
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The Gowanus Canal is an industrial waterway constructed in the mid-19th century by widening and deepening a natural tidal channel. It is ca. 3 km in length and empties into Gowanus Bay, an arm of New York Harbor. Its banks, reinforced by bulkheads and piers, became the site of intensive industrial activity, including oil refining, coal gasification, soap making and tanning. Even though much of the industrial activity along the canal has ceased, its sediments remain highly enriched in organic and inorganic contaminants, with combined sewer outfalls continuing to transport pollutants into the canal. The canal area remains densely …
Effect Of Regional Tectonic Setting On Local Fault Response To Episodes Of Volcanic Activity, Diana C. Roman, Philip Heron
Effect Of Regional Tectonic Setting On Local Fault Response To Episodes Of Volcanic Activity, Diana C. Roman, Philip Heron
Geology Faculty Publications
In this study we examine the interaction of tectonic and volcanically-generated stress fields, and their combined effect on patterns of volcanotectonic (VT) seismicity, by calculating Coulomb stress changes on local faults induced by a constant dike inflation event in a background stress field of systematically varying magnitude and orientation. We find that patterns of VT seismicity (earthquake locations and fault-plane solutions) resulting from dike inflation depend strongly on the relative strength and orientation of background tectonic stresses. Patterns of VT seismicity similar to those predicted by our Coulomb stress models have been observed at several recently active volcanoes, and appear …
Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen
Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen
Geology Faculty Publications
Trace element and Sr-Nd-Pb isotope compositions of basaltic lavas from 11 volcanoes spanning 1300 km of the Aleutian Island arc provide new constraints on the recycling of elements in melts and fluids derived from subducted oceanic crust and sediment. Despite a nearly twofold variation in the flux of sediment subducted along the Aleutians, proxies indicating the presence of sediment melt in the magma source, including Th/La and Th/Nd, do not vary systematically along strike. In contrast, ratios including B/La, B/Nb, B/Be, Cs/La, Pb/Ce, and Li/Y suggest that the quantity or composition of fluid transferred from the slab into the mantle …
Direct Analysis Of Solid Corrosion Products By Laser Ablation Icp-Ms: Method Development And The Interaction Of Aqueous Uranium, Gadolinium And Neodymium With Iron Shot And Iron (Iii) Oxide, James Cizdziel, Klaus J. Stetzenbach, Amy J. Smiecinski
Direct Analysis Of Solid Corrosion Products By Laser Ablation Icp-Ms: Method Development And The Interaction Of Aqueous Uranium, Gadolinium And Neodymium With Iron Shot And Iron (Iii) Oxide, James Cizdziel, Klaus J. Stetzenbach, Amy J. Smiecinski
Publications (YM)
The purpose of this report is to summarize the work and present conclusions of Project Activity Task ORD-RF-03 conducted under cooperative agreement number DE-FC28-04RW12237 between the U.S. Department of Energy and the Nevada System of Higher Education (NSHE). The work was conducted in the Harry Reid Center for Environmental Studies of the University of Nevada Las Vegas from October 1, 2004 to September 30, 2006. The purpose of the study was to develop a method using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for the direct analysis of iron corrosion products, to evaluate its capabilities, advantages, and limitations, and …
Geochemical Modeling Of Solubility And Speciation Of Uranium, Neptunium, And Plutonium, Zhongbo Yu, Yuyu Lin, Karen Johannesson, Amy J. Smiecinski, Klaus J. Stetzenbach
Geochemical Modeling Of Solubility And Speciation Of Uranium, Neptunium, And Plutonium, Zhongbo Yu, Yuyu Lin, Karen Johannesson, Amy J. Smiecinski, Klaus J. Stetzenbach
Publications (YM)
The purpose of this study is to model the solubility, speciation, and transport of three actinides: uranium (U), neptunium (Np), and plutonium (Pu) by a geochemical modeling tool under possible repository environmental conditions upon waste package failure. The dissolution concentration of three actinides in the waste package, their aqueous speciation after dissolving in the unsaturated zone (UZ), and transport processes in the saturated zone (SZ) along the groundwater flow path at Yucca Mountain (YM) are simulated by geochemical modeling calculations using PHREEQC. This model report was prepared in fulfillment of Groundwater Characterization at Yucca Mountain, Task II: Surface Complexation and …
Seagrass-Mediated Carbonate Dissolution And Early Diagenesis In Bahamas Bank Sediments, Xinping Hu
Seagrass-Mediated Carbonate Dissolution And Early Diagenesis In Bahamas Bank Sediments, Xinping Hu
OES Theses and Dissertations
This dissertation presents the results of studies examining the role that seagrasses play in carbonate dissolution and early diagenesis of Bahamas Bank sediments. Three aspects of this problem are addressed: (1) stable carbon isotopes as an indicator of early diagenesis of carbonates, using results of a field study; (2) carbonate dissolution stoichiometry and carbonate reprecipitation, using the results from closed-system sediment incubation studies; (3) carbonate dissolution and reprecipitation across the broader Bahamas Bank. In Chapter II, I examined δ13C in the dissolved inorganic carbon (DIC) of sediments with various degrees of seagrass densities. In low seagrass density and …
Sulfur Geochemistry And Diagenesis In A Gas Hydrate Terrane, Cascadia Margin, Offshore Oregon: Role Of Anaerobic Methane Oxidation, David Deigert, Walter S. Borowski
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 …25>
High Crystallinity Si-Ferrihydrite: An Insight Into Its Neel Temperature And Size Dependence Of Magnetic Properties, Thelma S. Berquo, Subir K. Banerjee, Robert G. Ford, R. Lee Penn, Thomas Pichler
High Crystallinity Si-Ferrihydrite: An Insight Into Its Neel Temperature And Size Dependence Of Magnetic Properties, Thelma S. Berquo, Subir K. Banerjee, Robert G. Ford, R. Lee Penn, Thomas Pichler
Geology Faculty Publications
Ferrihydrite, an antiferromagnetic iron oxyhydroxide with resulting magnetization due to uncompensated spins, is of great importance for the cycling of many trace metals in the environment. Four ferrihydrite samples prepared with 1.3 to 3.5 wt% of Si at different synthesis temperatures (7.5°C, 22°C, 50°C, and 75°C) were studied by temperature-dependent hysteresis loops, ZFC/FC susceptibility curves, ac susceptibility and Mössbauer spectroscopy. The incorporation of Si into the ferrihydrite during synthesis changed the properties of this mineral. Interestingly, seven sharp lines were observed in the X-ray diffraction pattern of the ferrihydrite samples prepared at 50°C and 75°C. In general, both XRD and …
Interdecadal-Decadal Climate Variability From Multi-Coral Oxygen Isotope Records In The South Pacific Convergence Zone Region Since 1650ad, Peipei Zhang
Geology Theses and Dissertations
Annual average oxygen isotope (δ18O) time series from five coral cores collected from Fiji and Tonga are used to construct a Fiji-Tonga Interdecadal-Decadal Pacific Oscillation (F-TIDPO) index of low frequency (>9yr and <55yr) climate variability in this area back to 1650 A.D. Presently, both Fiji and Tonga are located in the South Pacific Convergence Zone (SPCZ) salinity front region where the Interdecadal Pacific Oscillation (IPO) variation is most pronounced. We first demonstrate the consistency between this F-T IDPO index and a MSL pressure-based SPCZ Position Index (SPI) (1891-2000), thus verifying the ability of coral δ18O to record past interdecadal-decadal climatic variations in this region back to 1891. The F-T IDPO index is then shown to be synchronous with the IPO index (1856-2000), suggesting that this coral-based index effectively represents the interdecadal-decadal scale climate variance back to 1650. The consistently anti-phase spectrums of the F-T five-coral composite and the interdecadal-decadal components in equatorial Pacific coral δ18O series from Maiana [Urban et al., 2000] and Palmyra [Cobb et al., 2001] suggest that the simultaneous eastern expansion (western contraction) of the eastern salinity front of Western Pacific Warm Pool (WPWP) occurs at the same time as the northeast (southwest) movement of the SPCZ during a positive IPO (negative IPO) phase.
Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Geology Theses and Dissertations
Geochemical analysis and field relations of linear dolomite bodies occurring in outcrop in the Mohawk Valley of New York suggest that they have undergone significant fault-related hydrothermal alteration. The dolomite occurs in the Lower Ordovician Tribes Hill Formation, which is regionally an early Ordovician shaley limestone with patchy dolomitization. The outcrop has an en echelon fault, fracture, and fold pattern. A 3D ground penetrating radar survey of the quarry floor has helped to map out faults, fractures, anticlines, synclines and the extent of dolomitization. Most of the dolomitization occurs in fault-bounded synclines or “sags” flanked by anticlines. The dolomite structures …
Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May
Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May
United States Geological Survey: Publications
This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …
Impact Of Anthropogenic Combustion Emissions On The Fractional Solubility Of Aeroosol Iron: Evidence From The Sargasso Sea, Peter N. Sedwick, Edward R. Sholkovitz, Thomas M. Church
Impact Of Anthropogenic Combustion Emissions On The Fractional Solubility Of Aeroosol Iron: Evidence From The Sargasso Sea, Peter N. Sedwick, Edward R. Sholkovitz, Thomas M. Church
OES Faculty Publications
We report empirical estimates of the fractional solubility of aerosol iron over the Sargasso Sea during periods characterized by high concentrations of Saharan dust (summer 2003) and by low concentrations of aerosols in North American/maritime North Atlantic air masses (spring 2004 and early summer 2004). We observed a strong inverse relationship between the operational solubility of aerosol iron (defined using a flow-through deionized-water leaching protocol) and the total concentration of aerosol iron, whereby the operational solubility of aerosol iron was elevated when total aerosol iron loadings were low. This relationship is consistent with source-dependent differences in the solubility characteristics of …
Late Cretaceous To Paleocene Metamorphism And Magmatism In The Funeral Mountains Metamorphic Core Complex, Death Valley, California, Chris G. Mattinson, Joseph P. Colgan, James R. Metcalf, Elizabeth L. Miller, Joseph L. Wooden
Late Cretaceous To Paleocene Metamorphism And Magmatism In The Funeral Mountains Metamorphic Core Complex, Death Valley, California, Chris G. Mattinson, Joseph P. Colgan, James R. Metcalf, Elizabeth L. Miller, Joseph L. Wooden
All Faculty Scholarship for the College of the Sciences
Amphibolite-facies Proterozoic metasedimentary rocks below the low-angle Cenozoic Boundary Canyon Detachment record deep crustal processes related to Mesozoic crustal thickening and subsequent extension. A 91.5 ± 1.4 Ma Th-Pb SHRIMP-RG (sensitive high-resolution ion microprobe–reverse geometry) monazite age from garnet-kyanite-staurolite schist constrains the age of prograde metamorphism in the lower plate. Between the Boundary Canyon Detachment and the structurally deeper, subparallel Monarch Spring fault, prograde metamorphic fabrics are overprinted by a pervasive greenschist-facies retrogression, high-strain subhorizontal mylonitic foliation, and a prominent WNW-ESE stretching lineation parallel to corrugations on the Boundary Canyon Detachment. Granitic pegmatite dikes are deformed, rotated into parallelism, and …
High- And Ultrahigh-Pressure Metamorphism In The North Qaidam And South Altyn Terranes, Western China, Chris G. Mattinson, C. A. Menold, Jian-Xin Zhang, D. K. Bird
High- And Ultrahigh-Pressure Metamorphism In The North Qaidam And South Altyn Terranes, Western China, Chris G. Mattinson, C. A. Menold, Jian-Xin Zhang, D. K. Bird
All Faculty Scholarship for the College of the Sciences
The North Qaidam and South Altyn terranes extend approximately 1000 km across the northern Tibetan Plateau, and five localities preserve evidence of Early Paleozoic high-pressure (HP) or ultrahigh-pressure (UHP) metamorphism, including the presence of coesite, coesite pseudomorphs, and diamond. A review of the geology, petrology, and geochronology collected over the past 10 years since these localities were discovered supports a correlation of the North Qaidam and South Altyn terranes, offset 350-400 km across the Altyn Tagh fault. Geochronology interpreted to reflect eclogite-facies metamorphism yields ages between 500 and 420 Ma; detailed geochronology from one locality supports a protracted (tens of …
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
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 …
Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology
Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology
Earth, Environmental, and Atmospheric Sciences Publications
No abstract provided.
Data Report: Dissolved Sulfide Concentration And Sulfur Isotopic Composition Of Sulfide And Sulfate In Pore Waters, Odp Leg 204, Hydrate Ridge And Vicinity, Cascadia Margin, Offshore Oregon, Walter S. Borowski
EKU Faculty and Staff Scholarship
We report dissolved sulfide sulfur concentrations and the sulfur isotopic composition of dissolved sulfate and sulfide in pore waters from sediments collected during Ocean Drilling Program Leg 204. Porewater sulfate is depleted rapidly as the depth to the sulfate/methane interface (SMI) occurs between 4.5 and 11 meters below seafloor at flank and basin locations. Dissolved sulfide concentration reaches values as high as 11.3 mM in Hole 1251E. Otherwise, peak sulfide concentrations lie between 3.2 and 6.1 mM and occur immediately above the SMI. The sulfur isotopic composition of interstitial sulfate generally becomes enriched in 34 S with increasing sediment depth. …
Significance Of Polycyclic Aromatic Hydrocarbons (Pahs) And Petroleum Biomarker Compounds In Contaminated Passaic River Sediments, Michael A. Kruge
Significance Of Polycyclic Aromatic Hydrocarbons (Pahs) And Petroleum Biomarker Compounds In Contaminated Passaic River Sediments, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The lower Passaic River (northeastern New Jersey) flows through one of the most densely populated regions of the United States. The area’s long history of industrial activity is reflected in the complex and variable hydrocarbon composition of the river sediments. Sediments from river bottom grab samples at Newark and a 30 cm deep core at Kearny were subjected to thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). This technique offers a practical alternative for rapid, inexpensive analysis, simply employing milligram quantities of dry, disaggregated sediment, avoiding the use of hazardous organic solvents. For each sample, a total of 181 hydrocarbons and organosulfur compounds …
Sinkhole Structure Imaging In Covered Karst Terrain, Sarah E. Kruse, M. Grasmueck, Matthew Weiss, D. Viggiano
Sinkhole Structure Imaging In Covered Karst Terrain, Sarah E. Kruse, M. Grasmueck, Matthew Weiss, D. Viggiano
Geology Faculty Publications
Ground penetrating radar (GPR) and resistivity techniques have been widely used to map the locations of sinkholes in covered karst terrain. To determine whether a sinkhole is a likely preferential conduit for groundwater flow, however, requires higher-resolution imaging than that used in conventional sinkhole mapping surveys. Field observations combined with simulated surveys for a 15-m diameter 3-m deep sinkhole in west-central Florida are used to assess the resolution of GPR and resistivity surveys targeting the semiconfining unit that floors the sinkhole depression. 2D resistivity surveys clearly show the central depression as well as resistivity contrasts between the cover sediments within …
The Impact Of Acid Mine Drainage On West Little Sugar Creek, Vigo Co., In, Jodie L. Gibson
The Impact Of Acid Mine Drainage On West Little Sugar Creek, Vigo Co., In, Jodie L. Gibson
All-Inclusive List of Electronic Theses and Dissertations
This study evaluates the degree and extent of contamination in West Little Sugar Creek by analyzing water chemistry in the stream during low and moderate flow conditions. West Little Sugar Creek is located in Vigo County, Indiana and has been severely impacted by AMD discharging from the abandoned Green Valley Mine site. Stream water is commonly acidic (as low as pH 2.4) with elevated concentrations of Fe and Al and elevated trace elements including Ni, Zn, Cu, Cd, Cr, Co, and others, many of which exceed local and/or national surface water quality standards. Amorphous Fe and Al precipitates also form …
Geochemistry Of Benthic Foraminifera As An Environmental Indicator: A Study From Multiple Hydrographic Regimes, Chandranath Basak
Geochemistry Of Benthic Foraminifera As An Environmental Indicator: A Study From Multiple Hydrographic Regimes, Chandranath Basak
All-Inclusive List of Electronic Theses and Dissertations
The geochemistry (stable isotopes and Lracc clements) or living (sLaincd) calcareous benthic foraminifera was compared with ambient botlom water stable isotope values to provide modern analog conditions and calibrations for environmental and paleoenvironmental assessments. Stable isotope values of live (stained) bcnthic foraminifera were investigated from push core and multicorer samples from the North Pacific (on the Aleutian margin, water depth 1988m) and the South Australian Bight (water depth 2476m and 1634m). Living benthic foraminifera specimens collected from contaminated sites in the Venice Lagoon were analyzed for trace elements. Both the isotopic and the trace element study involved interpretation of modern …
A Preliminary Comparison Of The Sulfur Geochemistry Between Two Gas Hydrate Terranes, Michael D. Spicer, Walter S. Borowski
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 …
Results Of Chemical Analyses For Alcove 8/ Niche 3 Tracer Studies, Jeanette Daniels, Amy J. Smiecinski
Results Of Chemical Analyses For Alcove 8/ Niche 3 Tracer Studies, Jeanette Daniels, Amy J. Smiecinski
Publications (YM)
This is the final report detailing the analyses performed under ORD-FY04-011 "Chemical Analyses for Alcove 8/Niche 3 Tracer Studies," The work was performed under The University and Community College System of Nevada (UCCSN) and the Department of Energy (DOE) Cooperative Agreement DE-FC28-04RW12232, This task provided method development and analytical support for the Alcove 8/Niche 3 Tracer Studies in the Exploratory Studies Facility (ESF). Concentrations of tracers as well as major anions and cations were reported for samples provided by Lawrence Berkeley National Laboratory (LBNL) and the US Geological Survey (USGS). Samples were analyzed using High Performance Liquid Chromatography (HPLC) and …
Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee
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. …