Geochemistry Commons^™

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 (S^o, 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

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

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 …

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. …

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

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

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

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

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

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

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 …

Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement

Undergraduate Review

No abstract provided.

The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith

United States Geological Survey: Publications

SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds containing the stations. The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and diffuse sources on land to rivers and through the stream and river network. The model predicts contaminant flux, concentration, and yield in streams and has been used to evaluate alternative hypotheses about the important contaminant sources and watershed properties that control transport over large spatial scales.

This report provides …

Field, Petrographic, And Geochemical Characteristics Of Price Creek, Russ Mccormack

Undergraduate Review

No abstract provided.

Western Caribbean Sea Surface Temperatures During The Late Quaternary, Matthew W. Schmidt, Maryline J. Vautravers, Howard J. Spero

OES Faculty Publications

[1] Mg/Ca ratios in the planktonic foraminifera Globigerinoides ruber from Colombian Basin core ODP 999A suggest that Caribbean sea surface temperatures ( SSTs) were from 2.1 to 2.7°C colder than the present during the last three glacial maximums. In comparison, faunal derived SSTs ( SIMMAX method) show that August SSTs in the Caribbean varied < 2° over the past 360 kyr, whereas February SSTs varied between 21.0°C and 26.5°C. Changes in the Mg/Ca-SST record contain a strong 23 kyr periodicity, suggesting the Mg/Ca-SST record reflects a warm season weighted SST average rather than an annual mean SST. Combining several dissolution indices, we identify brief periods of decreased carbonate preservation in our record and show that MIS 11 stands out as the most intensive dissolution cycle in the Caribbean over the last 460 kyr. Comparison of Caribbean SST change with a similar estimate of tropical SST variability in the western Pacific over the past 360 kyr reveals shifts in the east-west tropical SST gradient that are coeval with glacial-interglacial climate change and consistent both with a southward migration of the glacial ITCZ and with a glacial El Niño-like mode of tropical circulation.

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 …

Assessing The Paleoceanographic Potential Of The Coral Montipora Venosa At Fanning Atoll, Central Equatorial Pacific, Alexa Stolorow

Geology Theses and Dissertations

As interest in global climate change increases, so does the need for better and more extensive climate proxies. The central equatorial Pacific has been established as the region with the largest ENSO-related sea surface temperature (SST) and precipitation (PPT) anomalies, which are known to impact global interannual climate variability. To date, the coral genus Porites has been most commonly utilized for coral-based paleo-reconstructions of ENSO and lower frequency phenomena. However, due to questions of biological artifacts in coral, to more fully understand coral-based reconstruction, different coral genera need to be analyzed.
In this study, oxygen (δ18O) and carbon (δ13C) isotopic …

The Effects Of Land Use Changes On Soil Carbon In The Russian Steppe, Andrew M. Ratigliano

Geology Theses and Dissertations

Increasing atmospheric CO2 levels within the past few centuries have led to many studies about the global carbon cycle. An important aspect in balancing the modern global carbon budget revolves around a missing sink of carbon. It is thought that the carbon accumulation in soil may be a significant component in this loss. As changes in land use under natural conditions have increased over the years, it is not well understood how these changes may affect the soil carbon. A useful technique in determining these changes are with the use of archived samples. Within a Russian steppe preserve that has …

Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu

All Faculty Scholarship for the College of the Sciences

Amphibolite-facies para- and orthogneisses near Dulan, in the southeast part of the North Qaidam terrane, enclose minor ultra-high pressure (UHP) eclogite and peridotite. Field relations and coesite inclusions in zircons from paragneiss suggest that felsic, mafic, and ultramafic rocks all experienced UHP metamorphism and a common amphibolite-facies retrogression. Ion microprobe U–Pb and REE analyses of zircons from two granitic orthogneisses indicate magmatic crystallization at 927 ± Ma and 921 ± 7 Ma. Zircon rims in one of these samples yield younger ages (397–618 Ma) compatible with partial zircon recrystallization during in-situ Ordovician-Silurian eclogite-facies metamorphism previously determined from eclogite and paragneiss …

The Earth All Around Us: Selected Building Stone In Lincoln, Nebraska. A Walking Tour, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Stone has been a primary building material for millennia. Cities, therefore, are treasure troves of earth materials. A wide variety of stones from many places are used for walls, as foundations to support entire buildings, as trim, and more recently as cladding (facing, an overlay). The Earth science teacher can find, in the limited space of an urban environment, a superb collection of stones with which to introduce students to these materials. The surfaces of stones on the outsides of buildings illustrate the durability and the vulnerability of each kind of stone to the local climate. And the history of …