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Evidence For Shallow Saltwater Intrusion: Wormsloe State Historic Site, Chatham County, Georgia, Chelsea E. Bush, Lori A. Farley, Tim J. Herold 2016 Georgia State University

Evidence For Shallow Saltwater Intrusion: Wormsloe State Historic Site, Chatham County, Georgia, Chelsea E. Bush, Lori A. Farley, Tim J. Herold

Georgia State Undergraduate Research Conference

No abstract provided.


Reconstructing Paleoenvironmental Conditions From Hydrothermally Altered Lacustrine Sediments From Hspdp West Turkana-Kaitio Core Material Via Coupled Mineralogical And Geochemical Analysis, Mamta Sanam Chaudhary 2016 Georgia State University

Reconstructing Paleoenvironmental Conditions From Hydrothermally Altered Lacustrine Sediments From Hspdp West Turkana-Kaitio Core Material Via Coupled Mineralogical And Geochemical Analysis, Mamta Sanam Chaudhary

Georgia State Undergraduate Research Conference

No abstract provided.


Anaerobic Dissociation Of Thiocyanate Under Controlled Ph And Temperature, Alero Gure 2016 Montana Tech of the University of Montana

Anaerobic Dissociation Of Thiocyanate Under Controlled Ph And Temperature, Alero Gure

Graduate Theses & Non-Theses

Thiocyanate (SCN-) is formed from both natural and industrial processes, including the use of cyanide to process gold and silver ores rich in sulfide minerals. In mining operations however, thiocyanate also plays a role as an alternative lixiviant to cyanide for leaching gold and silver out of their ores. Thiocyanate may be less toxic than cyanide but it is more stable and has proven to be more difficult to destroy in mining effluents. In addition, just like cyanide, an environmental contaminant of concern – nitrate – is the final product of the oxidation of thiocyanate.

This study investigated the chemical behavior of ...


Natural Acid Rock Drainage And Ferricrete Deposit Chemistry Of The Judith Mountains, Montana, Sara Edinberg 2016 Montana Tech of the University of Montana

Natural Acid Rock Drainage And Ferricrete Deposit Chemistry Of The Judith Mountains, Montana, Sara Edinberg

Graduate Theses & Non-Theses

The Judith Mountains are a low-elevation “island” mountain range in east-central Montana composed of a series of laccoliths and stocks cut by coarse-grained alkali granite and tinguaite dikes. The geology of the Judith Mountains in the vicinity of Red Mountain and Judith Peak, two of the tallest mountains in the range, is conducive to the creation of headwater streams that are naturally acidic. Extensive limonite staining on Red Mountain attests to the widespread presence of disseminated pyrite in hydrothermally altered porphyry rock. However, no major historical mining operations are known to the area. The acidic streams undergo neutralization in pH ...


Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan 2016 Montana Tech of the University of Montana

Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan

Graduate Theses & Non-Theses

Butte, Montana is the host to a Cu-Mo porphyry deposit and has been a location of mining interest since 1864. Once copper ore is removed from this deposit it goes through a smelting process. Copper smelting processes consist of roasting, smelting, concentrating, and fire refining. During smelting, metals are separated from the waste, or gangue material. Slag is the waste material from these processes. Non-ferrous slag, such as a copper ore, removes iron and silica from the original ore. There is much interest in slag postproduction for there is often still a significant weight percent of metals trapped within a ...


Using Naturally Occurring Radon 222 As A Tracer To Quantify Groundwater Fluxes To Streams, Mandy Machinal 2016 Montana Tech of the University of Montana

Using Naturally Occurring Radon 222 As A Tracer To Quantify Groundwater Fluxes To Streams, Mandy Machinal

Graduate Theses & Non-Theses

Naturally occurring radon in groundwater was used to test radon mixing models. Two different mixing models were used to quantify groundwater fluxes to streams; an analytical solution and a finite difference method. Two different bodies of waters were used in this study. The first location was Johnson Creek located in Grant-Kohrs Ranch in Deer Lodge, Montana. This is a small creek where lots of sampling points were taken. The stretch of Johnson Creek where radon samples were collected was about 0.34 km long with a flowrate between 0.01 m3/s and 0.017 m3/s. The second location ...


Low-Temperature Artificial Maturation Studies Of Type Ii And Type Iii Kerogens: Implications For Biogenic Gas Production, Albert Willy Nguena Kamga 2016 Old Dominion University

Low-Temperature Artificial Maturation Studies Of Type Ii And Type Iii Kerogens: Implications For Biogenic Gas Production, Albert Willy Nguena Kamga

Chemistry & Biochemistry Theses & Dissertations

Ancient organic matter (OM) in shales and coals, known mainly as Type II and Type III OM are known to produce both biogenic, thermogenic gas and oil. In this dissertation, mild artificial maturation, via closed system pyrolysis, is employed to determine the thermal reactivity of Type II and Type III OM beyond diagenesis. We select three Type II kerogens: i) Type II kerogen isolated from recent cores (3.3 Ma, Ro = 0.28) recovered from an upwelling basin in Namibia, Africa referred to as ODP Sediment, ii) Type II-S isolated from sediments (150 Ma, Ro = 0.38) recovered from an ...


Geochemical And Petrological Characterizations Of Peridotite And Related Rocks In Marquette County, Michigan, Andrew Lloyd Sasso 2016 Western Michigan University

Geochemical And Petrological Characterizations Of Peridotite And Related Rocks In Marquette County, Michigan, Andrew Lloyd Sasso

Master's Theses

This study characterizes the following rock units in Marquette County, Michigan in terms of geochemistry and petrology: (1) Presque Isle Peridotite, (2) Deer Lake Peridotite, (3) Yellowdog Peridotite, and (4) Black Rock Point Gabbro. Analyses were conducted to determine if any petrological or geochemical relationships exist between these units, and to assess the potential of these units to host magmatic sulfide deposits.

The generated data and chosen geotectonic proxies indicate that Black Rock Point Gabbro and Deer Lake Peridotite crystallized from unrelated magmas, probably during the formation of the Great Lakes Tectonic Zone (2.7-1.85 Ga). No evidence was ...


Geochemical And Petrological Studies On The Origin Of Nickel-Copper Sulfide Mineralization At The Eagle Lntrusion In Marquette County, Michigan, Benjamin Davis Hinks 2016 Western Michigan University

Geochemical And Petrological Studies On The Origin Of Nickel-Copper Sulfide Mineralization At The Eagle Lntrusion In Marquette County, Michigan, Benjamin Davis Hinks

Master's Theses

The Eagle magmatic intrusion is located in the Upper Peninsula of Michigan in Marquette County. It hosts a high grade magmatic nickel-copper sulfide ore deposit. Country rocks surrounding the Eagle intrusion are metamorphosed slate and greywacke of the Proterozoic Michigamme Formation and Archean granite-gneiss. The aim of this thesis is to characterize the magmatic sulfide mineral deposit at Eagle and to establish its relationship to the surrounding host rocks of the Baraga Basin area.

The Eagle East intrusion is located 600 meters east of the Eagle intrusion. These two intrusions are similar in composition and sulfide mineralization. Sulfide textural domains ...


Preliminary Investigations Of Seasonal Changes In The Geochemical Evolution Of The Logdson River, Mammoth Cave, Kentucky, Chris Groves, Darlene Anthony, Joe Meiman 2016 Western Kentucky University

Preliminary Investigations Of Seasonal Changes In The Geochemical Evolution Of The Logdson River, Mammoth Cave, Kentucky, Chris Groves, Darlene Anthony, Joe Meiman

Chris Groves

Many geochemical studies have been made of karst waters worldwide. Most data that provide the framework for our current understanding of the evolution of karst waters have come from sampling at discrete times and locations, such as springs or wells. Relatively few studies have been made of the geochemical evolution of groundwater as it moves through an open flow system. This paper addresses the seasonal changes in the geochemistry of the Logsdon River conduit as it passes through nearly 10km of the carbonate aquifer of south-central Kentucky . The most important control on the ability of groundwaters to dissolve limestone is ...


U-Pb Dating Of Speleogenetic Dolomite: A New Sulfuric Acid Speleogenesis Chronometer, Victor J. Polyak, Paula P. Provencio, Yemane Asmerom 2016 University of New Mexico

U-Pb Dating Of Speleogenetic Dolomite: A New Sulfuric Acid Speleogenesis Chronometer, Victor J. Polyak, Paula P. Provencio, Yemane Asmerom

International Journal of Speleology

The 1100-meter Big Room elevation level of Carlsbad Cavern, New Mexico USA, formed 4 Ma by hypogenic sulfuric acid speleogenesis (SAS). The age of the Big Room level of 4.0 ± 0.2 Ma was previously determined by dating alunite, a byproduct of speleogenesis, using the 40Ar/39Ar method. Duplication of these results is possible by radiometric dating of other byproducts interpreted to be speleogenetic (a byproduct of speleogenesis) such as calcite and dolomite in certain settings. XRD and TEM analyses of sample 94044, a piece of crust collected within the Big Room level of SAS just below ...


Agriculture Causes Nitrate Fertilization Of Remote Alpine Lakes, Elizabeth J. Hundey, Sam S.D. Russell, Fred Longstaffe, Katrina A. Moser 2016 Western University

Agriculture Causes Nitrate Fertilization Of Remote Alpine Lakes, Elizabeth J. Hundey, Sam S.D. Russell, Fred Longstaffe, Katrina A. Moser

Earth Sciences Publications

Humans have altered Earth’s nitrogen cycle so dramatically that reactive nitrogen (Nr) has doubled. This has increased Nr in aquatic ecosystems, which can lead to reduced water quality and ecosystem health. Apportioning sources of Nr to specific ecosystems, however, continues to be challenging, despite this knowledge being critical for mitigation and protection of water resources. Here we use D17O, d18O and d15N from Uinta Mountain (Utah, USA) snow, inflow and lake nitrate in combination with a Bayesian-based stable isotope mixing model, to show that at least 70% of nitrates in aquatic systems are ...


Climate, Ecology, And Human Evolution During The Plio-Pleistocene, Scott Adam Blumenthal 2016 Graduate Center, City University of New York

Climate, Ecology, And Human Evolution During The Plio-Pleistocene, Scott Adam Blumenthal

All Dissertations, Theses, and Capstone Projects

A major goal of paleoanthropology is to identify the selective pressures associated with hominin biological and behavioral evolution, yet establishing cause-effect relationships between climate, ecology, and human evolution remains problematic. This dissertation seeks to investigate hominin paleoecology in eastern Africa by reconstructing aspects of climate and ecology using stable isotope analysis.

The first part of this dissertation is focused on the ecology of primates and hominins. Modern tropical African ecosystems provide a useful model for understanding the ecological correlates of isotopic variation in the fossil record, and living primates provide a useful model for understanding the ecological significance of isotopic ...


Processes Controlling Carbon Cycling In Antarctic Glacier Surface Ecosystems, Elizabeth A. Bagshaw, Martyn Tranter, Jemma L. Wadham, Andrew G. Fountain, A. Dubnick, S. Fitzsimons 2016 Cardiff University

Processes Controlling Carbon Cycling In Antarctic Glacier Surface Ecosystems, Elizabeth A. Bagshaw, Martyn Tranter, Jemma L. Wadham, Andrew G. Fountain, A. Dubnick, S. Fitzsimons

Geology Faculty Publications and Presentations

Glacier surface ecosystems, including cryoconite holes and cryolakes, are significant contributors to regional carbon cycles. Incubation experiments to determine the net production (NEP) of organic matter in cryoconite typically have durations of 6-24 hours, and produce a wide range of results, many of which indicate that the system is net heterotrophic. We employ longer term incubations to examine the temporal variation of NEP in cryoconite from the McMurdo Dry Valleys, Antarctica to examine the effect of sediment disturbance on system production, and to understand processes controlling production over the lifetimes of glacier surface ecosystems. The shorter-term incubations have durations of ...


Comparison Of The Elemental Geochemistry Of The Arkansas Novaculite And The Boone Chert In Their Type Regions, Arkansas, J. Philbrick, E. Pollock, A. Potra 2016 University of Arkansas, Fayetteville

Comparison Of The Elemental Geochemistry Of The Arkansas Novaculite And The Boone Chert In Their Type Regions, Arkansas, J. Philbrick, E. Pollock, A. Potra

Journal of the Arkansas Academy of Science

The name Arkansas Novaculite was proposed by A.H. Purdue, 1909 to replace the name Arkansas Stone assigned by L. S. Griswold, 1892, but deemed too generic, to an interval of Early Devonian-Early Mississippian, very fine-grained, even textured, siliceous sedimentary rock famous for use as whetstones. The interval is exposed along the margins of the Benton Uplift, south flank of the Ouachita Mountains, west-central Arkansas, where it reaches a maximum thickness of 243.8 m (800 ft). The Arkansas Novaculite comprises informal lower and upper members characterized by massive beds of nearly pure novaculite, separated by a shale-bearing middle member ...


Geochemical Processes And Controls Affecting Water Quality Of The Karst Area Of Big Creek Near Mt. Judea, Arkansas, V. Brahana, J. Nix, C. Kuyper, T. Turk, F. Usrey, S. Hodges, C. Bitting, K. Ficco, E. Pollock, R. Quick, B. Thompson, J. Murdoch 2016 University of Arkansas, Fayetteville

Geochemical Processes And Controls Affecting Water Quality Of The Karst Area Of Big Creek Near Mt. Judea, Arkansas, V. Brahana, J. Nix, C. Kuyper, T. Turk, F. Usrey, S. Hodges, C. Bitting, K. Ficco, E. Pollock, R. Quick, B. Thompson, J. Murdoch

Journal of the Arkansas Academy of Science

Karst regions typically are considered to be vulnerable with respect to various land-use activities, owing to the intimate association of surface and groundwater and lack of contaminant attenuation provided by most karst aquifers. Inasmuch as the soluble rocks of the karst landscape can be dissolved to create large, rapid-flow zones that compete successfully with surface streams, groundwater and subsurface flow represent a much larger component of the hydrologic budget in karst regions than in areas where non-soluble rocks predominate. Karst areas typically are distinguished by being unique, but some general approaches can be applied to characterize the hydrology of the ...


Water Chemistry Under A Changing Hydrologic Regime: Investigations Into The Interplay Between Hydrology And Water-Quality In Arid And Semi-Arid Watersheds In Colorado, Usa., Taylor Joe Mills 2016 University of Colorado at Boulder

Water Chemistry Under A Changing Hydrologic Regime: Investigations Into The Interplay Between Hydrology And Water-Quality In Arid And Semi-Arid Watersheds In Colorado, Usa., Taylor Joe Mills

Geography Graduate Theses & Dissertations

Climate and land-use change may alter the hydrologic regime of a watershed by changing the frequency, intensity, duration, and annual timing of water input to the landscape. These changes can affect water table dynamics, streamflow volumes, and hydrologic flowpaths through the landscape. Water serves to drive geochemical reactions, weathering minerals, and releasing solutes to terrestrial and aquatic ecosystems, and changes in hydrologic regime can impact not only water quantity but also the quality of water reaching streams or aquifers. Thus, there is a need to understand how hydrologic conditions relate to stream and groundwater chemistry to better anticipate possible water-quality ...


Evaluating Mineralogy At Terrestrial Analogs For Early Mars: Detection And Characterization Of Clays With Xrd And Investigation Of Iron Substitution In Natroalunite, Laura Grace Beckerman 2016 University of Colorado at Boulder

Evaluating Mineralogy At Terrestrial Analogs For Early Mars: Detection And Characterization Of Clays With Xrd And Investigation Of Iron Substitution In Natroalunite, Laura Grace Beckerman

Geological Sciences Graduate Theses & Dissertations

The Mars Science Laboratory (MSL) Curiosity rover is equipped with CheMin, the first x-ray diffraction (XRD) instrument on Mars, for in situ mineralogy as part of its mission to seek evidence of past habitability at Gale Crater. Detection and characterization of hydrated minerals like clays and sulfates provides crucial insight into Mars’ early geochemistry. For example, clays are often interpreted as having formed in lacustrine environments at neutral pHs, while sulfates such as jarosite are evidence of acid sulfate alteration.

However, CheMin’s inability to remove non-clay minerals and to preferentially orient samples may pose significant challenges to clay detection ...


Quantifying Sources, Distribution, And Processing Of Light Absorbing Aerosols In The Cryosphere: A Comparison Of Dissolved And Refractory Black Carbon In Polar And High Mountain Regions, Alia Lauren Khan 2016 University of Colorado at Boulder

Quantifying Sources, Distribution, And Processing Of Light Absorbing Aerosols In The Cryosphere: A Comparison Of Dissolved And Refractory Black Carbon In Polar And High Mountain Regions, Alia Lauren Khan

Civil Engineering Graduate Theses & Dissertations

Light absorbing aerosols (LAAs), such as black carbon (BC), in snow and ice are one of the least understood parameters in global climate models. This is due to complicated physical processes within the cryosphere and too few in situ observations. BC is derived from the incomplete combustion of biomass and fossil fuels and can enhance melt water generation and glacial recession when deposited on snow and ice surfaces. Measurements are limited due to the difficulty of collecting and preserving samples for analysis from remote environments. In order to help build a larger repository of ground observations, this dissertation explores the ...


Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan 2016 University of Denver

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day ...


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