Geochemistry Commons^™

Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore

USF Tampa Graduate Theses and Dissertations

The flux of CO2 between the ocean and the atmosphere is an important measure in determining local, global, and regional, as well as short term and long term carbon budgets. In this study, air-sea CO2 fluxes measured using a floating chamber were used to examine the spatial and temporal variability of CO2 fluxes in Florida Bay. Measurements of dissolved inorganic carbon and total alkalinity obtained concurrently with chamber measurements of CO2 flux allowed calculation of ΔpCO2 from flux measurements obtained at zero wind velocity. Floating chamber measurements of ΔpCO2 were subsequently coupled with wind speed data to provide a simple …

Dissemination Of Geological Information In Avoiding Geotechnical Risks Associated With Tunnel Construction: Lessons Learned From Deep Voids In Marble In Lower Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Leah Scott

Publications and Research

Test boring associated with the recently accomplished City Water Tunnel # 3 in Manhattan, New York City revealed moderately to highly weathered marble with insoluble silicate residues composed mostly of phlogopite, chlorite, and tremolite. Apparent control on the weatherability of the marble was in response to original mineral constituents dominating this lithology. Encountered marble samples ranged between pure calcitic to mixed dolomitic/siliceous types. Fresh marble samples collected from adjacent boring locations revealed characteristic geochemical data: Lime (25-45%), Silica (4-7%), Alumina (1-3%), MgO (5-20%), and LOI (35-42%); compressive strength of unweathered marble varied between 2000-3000 Kg/cm². Relict foliations with …

Geogram 2011, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Mobile Technology As A Tool For Enhancing Student Learning In Geosciences, Sam Matson

Mobile Learning Symposium

Incorporation of mobile technology into the post-secondary classroom is becoming increasingly common as universities seek to facilitate active, student-centered learning through rapid access to information, connect students with course content through social media, and evaluate digital alternatives to conventional instructor-student interaction. The m-Learning Scholars Program at Boise State University was initiated during the 2010 – 2011 academic year, and provides a venue for exploring the potential of mobile technology to enhance student learning in the geosciences. Through this program, 38 students in an introductory Earth History course for non-geoscience majors each purchased a subsidized handheld device (iPod touch) that they …

Magnetic Properties Of Ilmenite‐Hematite Single Crystals From The Ecstall Pluton Near Prince Rupert, British Columbia, Sarah J. Brownlee, Joshua M. Feinberg, Takeshi Kasama, Richard J. Harrison, Gary R. Scott, Paul R. Renne

Environmental Science and Geology Faculty Research Publications

Paleomagnetic studies of the 91 Ma Ecstall pluton and other Cretaceous plutons of British Columbia imply large northward tectonic movements (>2000 km) may have occurred during the tectonic evolution of western North America. However, more recent studies have shown that the eastern edge of the Ecstall pluton experienced considerable mineralogical changes as younger Eocene plutons, such as the ∼58 Ma Quottoon Pluton, were emplaced along its margins. We investigated changes in the rock magnetic properties associated with this reheating event by examining isolated grains of intergrown ilmenite and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of …

Effects Of Weathering On Aromatic Compounds In Beach Tars From The Deepwater Horizon Disaster, Gulf Of Mexico Coast, Usa, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Operators aboard the Deepwater Horizon drilling platform lost control of the Macondo No. 1 well about 90 km southwest of the Louisiana coast on April 20, 2010, leading to a catastrophic release of ca. 550 Gg of crude oil over the next 86 days [1]. Oil from the spill soon found its way to nearby coastal areas, leaving tarry deposits on beaches and marshes. Oil was reported on the beach at Gulf Shores, Alabama (180 km northeast of the well) on June 5 and the relatively fresh sample discussed herein (GSA) was collected that same day. Oil reached the beach …

The Vinylguaiacol/Indole Or Vgi ("Veggie") Ratio: Assessing Relative Contributions Of Terrestrial And Aquatic Organic Matter To Sediments, Michael A. Kruge, Kevin K. Olsen, Jaroslaw W. Slusarczyk, Elaine Gomez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

In studies of the organic matter (OM) fraction of marine, estuarine, fluvial, or lacustrine sediments, one of the most fundamental distinctions to be made is that between terrestrial and aquatic OM. To supplement the parameters commonly used for this purpose (e.g., C/N and stable isotope ratios), we proposed the Vinylguaiacol/Indole or VGI ("Veggie") ratio, defined as [vinylguaiacol / (indole + vinylguaiacol)] using data produced by analytical pyrolysis-gas chromatography/mass spectrometry of dried, homogenized sediment samples [1]. The ratio employs the peak areas of these two compounds on the mass chromatograms of their molecular ions (m/z 150 and 117, respectively). Major pyrolysis …

Predicted Velocity And Density Structure Of The Exhuming Papua New Guinea Ultrahigh‐Pressure Terrane, Sarah J. Brownlee, Bradley R. Hacker, Matthew Salisbury, Gareth Seward, Timothy A. Little, Suzanne A. Baldwin, Geoffrey A. Abers

Environmental Science and Geology Faculty Research Publications

New electron backscatter diffraction measurements show that the Papua New Guinea (PNG) ultrahigh‐pressure (UHP) terrane is dominated by rocks with weakly oriented quartz and feldspar and less abundant strongly oriented hornblende, clinopyroxene, and mica. Velocities measured at high pressures (600 MPa) show that V_P is 5.8–6.3 km/s for gneiss samples, 6.5–7.7 km/s for amphibolite, and 7.7–8.2 km/s for eclogite and V_S is 3.4–3.9 km/s for gneiss, 4.0–4.4 km/s for amphibolite, and 4.5–4.6 km/s for eclogite. Velocities and anisotropies calculated from mineral crystal preferred orientations (CPOs) are equivalent to within 5% of the measured values. The highest seismic anisotropy …

Assessing Ageing At Beaver Reservoir, Northwest Arkansas: Limnological, Geochemical & Paleolimnological Approach, Byron Anthony Winston

Graduate Theses and Dissertations

Access to potable water has been arguably one of the most important requisites for the advancement of human civilization on earth. As a result, man in his infinite wisdom devised the dam and formed reservoirs, (man- made lakes), to exploit water resources at will. In all natural lakes and reservoirs changes occur in the water quality parameters as it relates to chemical nutrients, temperature and turbidity over time. These changes are collectively referred to as "Reservoir Ageing", of which sedimentation and eutrophication are primary. Reservoir Ageing has consequences which adversely affect and defeat many of the intended uses of the …

Solving The Mystery Of The Atacama Nitrate Deposits: The Use Of Stable Oxygen Isotope Analysis And Geochemistry, Ji-Hye Seo

The Journal of Purdue Undergraduate Research

The Atacama Desert, Chile, one of the oldest and driest deserts on Earth, is unique because it contains the largest known nitrate deposits in the world. The origin of these nitrate deposits has been a mystery since their discovery in the 1800s. There are two possible sources of natural nitrate: microbiological processes and photochemical reactions. The majority of material on Earth follows mass-dependent fractionation between stable oxygen isotopes with the abundance of ¹⁷Ο (denoted by δ) as half that of ¹⁸O. This relationship is quantified by Δ¹⁷O = δ¹⁷O – ½ δ¹⁸O, …

Evaluation Of The Carbon Budgets In The Forested And Agricultural Soils Of The Semi-Arid Mogollon-Datil Highlands And Rio Grande Basin, Ryan Reeves^, Lixin Jin*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

The Nature, Origin And Preservation Of Amide Organic Nitrogen In Organic Matter, Georgina Anne Mckee

Chemistry & Biochemistry Theses & Dissertations

Past studies have found much of nonliving sedimentary/aqueous nitrogen-containing organic matter (NCOM) is composed of amides, assumed to be peptides/proteins. Their lability calls into question their survival, and several hypotheses have been suggested to explain this. Using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and nuclear magnetic resonance (NMR) spectroscopy I investigated the molecular amide composition in sedimentary/aqueous systems while reassessing their preservation and formation routes.

Development of a suitable methodology is essential for successful NCOM study due to electrospray ionisation source requirements: sediment samples need to be rendered into solution. Based on NMR and FT-ICR-MS analysis, I determined …

Insights Into Chemical Structure Changes Of Kerogen From Bituminous Coal In Response To Dike Intrusions Investigated By Advanced Solid-State 13C Nmr, Yuan Li

Chemistry & Biochemistry Theses & Dissertations

Variations in the chemical structures of kerogens From highly volatile bituminous coal located near two igneous dike intrusions in the Illinois Basin were examined in detail by advanced solid-state ¹³C nuclear magnetic resonance (NMR) spectroscopy. Spectral-editing techniques were used to identify specific functional groups. Direct polarization was used to quantify different functional groups. ¹H-¹³C two- dimensional heteronuclear NMR was used to examine connectivities and proximities, and ¹H-¹³C long-range recoupled dipolar dephasing was used to estimate aromatic cluster sizes. With decreasing distance to dike contacts and increasing thermal maturity (vitrinite reflectance R₀ from …

Environmental History Of A Closed-Basin Lake In The Us Great Plains: Diatom Response To Variations In Groundwater Flow Regimes Over The Last 8500 Cal. Yr Bp, William O. Hobbs, Sherilyn C. Fritz, Jeffery R. Stone, Joseph J. Donovan, Eric C. Grimm, James E. Almendinger

Department of Earth and Atmospheric Sciences: Faculty Publications

Sediment records from closed-basin lakes in the Northern Great Plains (NGP) of North America have contributed significantly to our understanding of regional paleoclimatology. A high-resolution (near decadal) fossil diatom record from Kettle Lake, ND, USA that spans the last 8500 cal. yr BP is interpreted in concert with percent abundance of aragonite in the sediment as an independent proxy of groundwater flow to the lake (and thus lake water level). Kettle Lake has been relatively fresh for the majority of the Holocene, likely because of the coarse substrata and a strong connection to the underlying aquifer. Interpretation of diatom assemblages …

Full Conference Program With Abstracts, Jason S. Polk, Leslie A. North

International 2011 Conference on Karst Hydrogeology and Ecosystems

No abstract provided.

The Impact Of Modern Weathering On The Geochemistry Of A Marine Permo-Triassic Boundary Section, Jeremy Christopher Williams

Graduate Masters Theses

The Permian-Triassic Boundary (PTB) marks the end-Permian extinction, the greatest mass extinction recorded in Earth's history. The Attargoo PTB section located in Spiti Valley, Himachal Pradesh, India was situated along the north continental margin of Gondwana-land in the Neo-Tethys Ocean during the end-Permian extinction. In Spiti Valley, PTB sections such as Attargoo are exposed by a thin (~ 2cm) ferruginous layer separating the Permian black shale from Triassic Limestone. Studies that have presented geochemical data to support a theory of the end-Permian extinction lack any interpretation of post-depositional effects on Spiti Valley PTB sections. In order to accurately present a …

Determining The Lon-Exchange Mechanism Of Strontium Into A Niobium Doped Titanosilicate, Samantha Jane Kramer

Masters Theses & Specialist Projects

A 25% niobium substituted sitinakite was exchanged with strontium as time resolved X-ray diffraction data was collected. The structural modeling of this data by Rietveld method1 has lead to the determination of the atomic positions of the ions and unit cell parameters as strontium occupancy increases.

The starting material of the exchange experiment is the protonated phase, H2Nb0.67Ti1.33SiO7·1.9 H2O, with space group P42/mcm2,3. Once strontium (Sr2+) enters the unit cell, extra-framework H2O molecules shift to provide the necessary hydration coordination. These new positions of H2O result in a lowering of symmetry to the P-42m space group, and it is thought …

Measuring The Rate Of Garnet Growth: Implications For Rb-Sr Garnet Chronology, Jessica Sousa

Boise State University Theses and Dissertations

Garnet growth rates have provided valuable information for understanding the rates of tectonometamorphic processes. In theory, during its growth, garnet records the decay of 87Rb within a rock matrix as steadily increasing ⁸⁷Sr/⁸⁶Sr from core to rim. By measuring the Sr isotopic zoning within garnet and matrix Rb/Sr and ⁸⁷Sr/⁸⁶Sr, the rate of garnet growth can be determined. To test this, we used ID-TIMS to measure Rb-Sr data for five samples from three major orogenic belts: central New England, southernmost Chile, and western Italian Alps. These new data introduce two major difficulties encountered using …

An Analysis Of The Stability And Transport Of Co2 On Mars And Iapetus: Increasing Accuracy Via Experiments And Photometry, David Garrison Blackburn

Graduate Theses and Dissertations

Volatile transport of carbon dioxide is most relevant on two planetary bodies in our solar system: Mars and Iapetus. We experimentally measured the sublimation rate of CO2 ice under simulated martian conditions and developed a model based on our experimental results. We experimentally verified that solar irradiance is the primary control for the sublimation of CO2 ice on the martian poles with the amount of radiation striking the surface being controlled by variations in the optical depth, ensuring the formation and sublimation of the seasonal cap. Our model, supported by comparison of MGS-MOC and MRO-HiRISE images, shows that ~ 0.4 …

Pleistocene Climate In Alaska From Stable Isotopes In An Ice Wedge, Corinne Y. Griffing

UNLV Theses, Dissertations, Professional Papers, and Capstones

The CRREL permafrost tunnel offers a unique opportunity to sample ice wedges in a climate-controlled environment, penetrating frozen silts which host massive ground ice that may record Dansgaard-Oeschger (D-O) and Heinrich Events. Ice wedges in the tunnel have been dated to approximately 36-22 ka (Hamilton et al., 1988), allowing the paleoclimate of the region to be reconstructed during MIS 3, when D-O and Heinrich events were documented in various other records. These climate cycles are rapid climate oscillations that have been recognized in records from the Arctic and subarctic, and suggest that climate can rapidly shift by 10°C over millennial …