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Full-Text Articles in Geochemistry

Geochemical Analysis Of Cenozoic Fossil Conifers At High Latitudes: Implications For Molecular Preservation And Environmental Change, Caitlyn Witkowski Apr 2010

Geochemical Analysis Of Cenozoic Fossil Conifers At High Latitudes: Implications For Molecular Preservation And Environmental Change, Caitlyn Witkowski

Honors Projects in Science and Technology

Fossil materials record ancient life and their adapted environment. Arctic plant fossils are critical for our understanding of the Earth’s paleoenvironment when high latitudes were under ice-free conditions. All Arctic plant fossils in this research are conifers, plants conducive for morphological and molecular study because of their incredible genetic stability. Miocene (15 million year old) and Pliocene (5 million year old) conifer leaves were collected from Banks Island, Canada (Williams et al., 2008). Samples were analyzed and compared with Paleocene (60 million year old) and Eocene (45 million year old) samples from Axel Heiberg Island, Canada and with modern equivalent …


Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry Mar 2010

Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry

Earth and Soil Sciences

Detrital zircon studies of miogeoclinal sediments can help provide a deeper look into the mechanisms leading to continental breakup by studying the evolution of the continental margin of North America. Few detrital zircon studies have been conducted to support previous research and theories about the sedimentation of the Miogeocline from the Neoproterozoic to the Cambrian. Studies targeted at the Basin and Range province of the western United States show a trend of increasing local sediment sources. We analyzed detrital zircons from the Pilot and Deep Creek Ranges in Nevada and Utah via LA-MC-ICP-MS at the University of Arizona LaserChron Center …


Comparison Of Carbon Stocks & Importance Values In Correlation With Past Land Use In The Gordon Natural Area, Timothy Hoffer, Steffen Lubbe Jan 2010

Comparison Of Carbon Stocks & Importance Values In Correlation With Past Land Use In The Gordon Natural Area, Timothy Hoffer, Steffen Lubbe

Forest Carbon Storage Study Documents

No abstract provided.


Forest Analysis Of The Gordon Natural Area Focusing On Carbon Stock, Forest Structure, And Forest Composition, R. Dicce, D. Drake, D. Mackey, P. Avery Jan 2010

Forest Analysis Of The Gordon Natural Area Focusing On Carbon Stock, Forest Structure, And Forest Composition, R. Dicce, D. Drake, D. Mackey, P. Avery

Forest Carbon Storage Study Documents

No abstract provided.


Geochemical Investigation Of An Offshore Sewage Sludge Deposit, Barcelona, Catalonia, Spain, Michael A. Kruge, Albert Permanyer, Jordi Serra, Danlin Yu Jan 2010

Geochemical Investigation Of An Offshore Sewage Sludge Deposit, Barcelona, Catalonia, Spain, Michael A. Kruge, Albert Permanyer, Jordi Serra, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

For 20 years ending in the 1990’s the city of Barcelona discharged the products from a large primary sewage treatment plant directly into the Mediterranean Sea via underwater conduits. About ca. 3 million m3 of relict sewage sludge, rich in organic matter and heavy metals, has spread over an elongated area offshore, due to successive ruptures of the conduits. The use of the discharge pipes ceased, but he sludge deposit remains in place for the time being.

To understand the history and present state of the sludge deposit in advance of future remediation, a program of geophysical mapping, sampling, …


Mineralization In The San Juan Mountains, Colorado, William M. Sheriff Jan 2010

Mineralization In The San Juan Mountains, Colorado, William M. Sheriff

Open Access Theses & Dissertations

none


Trace Metal Biogeochemistry In The Western North Pacific, Peter Lynn Morton Jan 2010

Trace Metal Biogeochemistry In The Western North Pacific, Peter Lynn Morton

OES Theses and Dissertations

Dissolved and suspended particulate samples collected during the Intergovernmental Oceanographic Commission 2002 Contaminant Baseline Survey were analyzed to determine the surface and vertical distributions of Cd, Co, Cu, Mn, Ni Zn and Pb across the western and central North Pacific.

Dissolved trace metal concentrations were measured using a novel isotope dilution-ICP-MS method after extraction over an 8-hydroxyquinoline resin column and validated through the use of the SAFe consensus reference materials. Filtered suspended particulate matter was digested using an HCl/HNO3/HF mixture and analyzed by HR-ICP-MS to obtain total particulate concentrations for the trace metals and other tracer elements such as Al, …


Late Permian Paleoenvironmental Factors Expounded Through Analysis Of A Forest-Floor Paleosol Profile, Karoo Basin, South Africa, Cassi Knight Jan 2010

Late Permian Paleoenvironmental Factors Expounded Through Analysis Of A Forest-Floor Paleosol Profile, Karoo Basin, South Africa, Cassi Knight

Honors Theses

Beaufort Group paleosols from the Karoo Basin, South Africa, record the paleoenvironmental conditions that existed prior to and after the Permian-Triassic extinction event. Paleosol exposures from Wapadsberg Pass, Eastern Cape Province, represent a well- preserved forest-floor litter overlying an interpreted inceptisol, a condition unique to the basin. Vegetation that colonized this landscape included a canopy of the gymnosperm Glossopteris and an understory of sphenopsids (Phyllotheca and Trizygia). Wapadsberg Pass paleosol sites were sampled for petrographic and geochemical analyses to constrain interpretations of Late Permian paleoenvironmental conditions that existed ~ 70 m below the Permian-Triassic Boundary (PTB). This project focuses on …


Lithium- And Oxygen- Isotope Profiles Of A Mid-Atlantic Ridge Oceanic Core Complex: The Atlantis Massif, 30°N, Ellen J. Crapster-Pregont Jan 2010

Lithium- And Oxygen- Isotope Profiles Of A Mid-Atlantic Ridge Oceanic Core Complex: The Atlantis Massif, 30°N, Ellen J. Crapster-Pregont

Honors Theses

Oxygen (O) and lithium (Li) are fluid-mobile elements used as geochemical tracers of a crustal component in the mantle. The isotopes of each element fractionate according to the degree and temperature of hydrothermal alteration. Previous studies demonstrate that Li and O isotopic trends are coupled within the upper crust near mid-ocean ridges but are decoupled in subduction-related volcanism. To better understand the average crustal signature of these systems, it is necessary to characterize these systems in the presently poorly understood lower oceanic crust. This study uses lower crustal samples from IODP Expedition 305 Hole U1309D exhumed at the Atlantis Massif, …


A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio Jan 2010

A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio

OES Faculty Publications

We report the distribution of cobalt (Co) in the Ross Sea polynya during austral summer 2005-2006 and the following austral spring 2006. The vertical distribution of total dissolved Co (dCo) was similar to soluble reactive phosphate (PO(4)(3-)), with dCo and PO(4)(3-) showing a significant correlation throughout the water column (r(2) = 0.87, 164 samples). A strong seasonal signal for dCo was observed, with most spring samples having concentrations ranging from similar to ~ 45-85 pM, whereas summer dCo values were depleted below these levels by biological activity. Surface transect data from the summer cruise revealed concentrations at the low range …


Hydrogeochemistry Of Caves Drip Water At Selected Caves In Peninsular Malaysia., Nor Bakhiah Baharim Jan 2010

Hydrogeochemistry Of Caves Drip Water At Selected Caves In Peninsular Malaysia., Nor Bakhiah Baharim

Student Works (2010-2019)

This preliminary study represents the study on hydrogeochemical of caves drip water throughout Peninsular Malaysia. All samples were analysed for pH, Total Dissolved Solid (TDS), Dissolved Oxygen (DO), Conductivity, cation and anion. Despite local hydrological and geological differences among sampling sites, the monitoring revealed significant synchronous intersite variations that related to rainfall variation and control the volume of water input. The constant hydraulic pressure is expected in karst system as a result of moist condition of tropical region and rainfall throughout the year. Drip sites were classified into to two classifications which are seepages flow and seasonal flow. A simplified …


Characterization Of Mantle/Crust Interactions Using Pb Isotope Analyses Of Lavas In The Southern Rio Grande Rift, New Mexico, Lynnette Crocker Jan 2010

Characterization Of Mantle/Crust Interactions Using Pb Isotope Analyses Of Lavas In The Southern Rio Grande Rift, New Mexico, Lynnette Crocker

Open Access Theses & Dissertations

The Pb isotope composition of volcanic rocks in the Rio Grande Rift (RGR) can be used to investigate the interaction of mantle melts with continental lithosphere, and has important implications for the composition of the lithosphere. We suggest some compositional signatures may pre-date current tectonic processes. Existing data from several volcanic fields in New Mexico show a converging pattern on a very limited Pb isotope range, corresponding to lower crustal xenolith compositions from Kilbourne Hole. The different volcanic fields show Pb isotope trends diverging from this lower crustal composition, likely depicting mixing with different upper crustal reservoirs. These very common, …


Application Of Copper And Zinc Isotopes To Fingerprint Metal Sources And Identify Attenuation Mechanisms In The Abandoned Waldorf Mine Area, Clear Creek County, Colorado, Suzan Aranda Luna Jan 2010

Application Of Copper And Zinc Isotopes To Fingerprint Metal Sources And Identify Attenuation Mechanisms In The Abandoned Waldorf Mine Area, Clear Creek County, Colorado, Suzan Aranda Luna

Open Access Theses & Dissertations

Acid rock drainage (ARD) is caused by the oxidative weathering of sulfide minerals. Sulfur is oxidized by dissolved oxygen or Fe(III) and sulfate ions, metals, and protons are released into the environment. Hence, the pH of nearby water and soils often decreases in response to ARD while metal concentrations increase. Because a large part of the Rocky Mountains of Colorado are highly mineralized (i.e., the Colorado Mineral Belt), ARD is a serious problem in this region. Moreover, the many abandoned mining areas in the Rocky Mountains that include waste rock piles, tailings impoundments, and surface disturbances add to the problem …


Copper Isotope Fractionation During Surface Adsorption And Intracellular Incorporation By Bacteria, Jesica Urbina Navarrete Jan 2010

Copper Isotope Fractionation During Surface Adsorption And Intracellular Incorporation By Bacteria, Jesica Urbina Navarrete

Open Access Theses & Dissertations

Copper isotopes may prove to be a useful tool for investigating bacteria-metal interactions recorded in natural waters, soils, and rocks. However, experimental data that constrain Cu isotope fractionation in biologic systems are limited and unclear. In this study we utilized Cu isotopes (65Cu) as a tool to investigate Cu-bacteria interactions, including surface adsorption and intracellular incorporation. Experiments were conducted with individual Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial species as well as with bacterial consortia from several natural environments. Adsorption experiments were conducted with live or dead cells over the pH range 2.5 to 6. Surface adsorption of Cu …


Granulometry And Geochemistry Of Dust Emission From Owens (Dry) Lake, California, Analila Rojo Jan 2010

Granulometry And Geochemistry Of Dust Emission From Owens (Dry) Lake, California, Analila Rojo

Open Access Theses & Dissertations

Owens (dry) Lake, the terminus of Owens River, is located in the Basin and Range physiographic province in east–central California. The transformation of Owens Lake into a desiccated desert playa (approximately 280 km2) via diversion of the river into the Los Angeles Aqueduct (in 1913) led to extensive wind erosion, making the playa one of the most intense sources of airborne dust in the Western Hemisphere. The processes that direct the chemical and mineralogical composition of surface sediments at Owens (dry) Lake and the physical mechanisms of wind erosion, saltation and dust emission at Owens (dry) Lake are well–understood. However, …


New Infrared Spectral Data For 27 Asteroids: An Investigation Of Meteorite-Asteroid Relationships By Using The Modified Gaussian Model, Katherine Marie Gietzen Dec 2009

New Infrared Spectral Data For 27 Asteroids: An Investigation Of Meteorite-Asteroid Relationships By Using The Modified Gaussian Model, Katherine Marie Gietzen

Graduate Theses and Dissertations

Asteroids provide unique insights into the origin and early history of the solar system. Since asteroids are considered to be fairly pristine, studying them provides opportunities to learn more about the primordial solar system, its materials, processes and history. Since the discovery in 1801 of the first asteroid, Ceres, during the era when everyone was searching for the "missing planet", astronomers have been trying to understand what they are, where they came from, why they exist and what they can tell us about how our solar system formed and evolved.

Within the asteroid population are a number of sub-populations, the …


Geogram 2009, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2009

Geogram 2009, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Geometry Of The Trachyte Mesa Intrusion, Henry Mountains, Utah: Implications For The Emplacement Of Small Melt Volumes Into The Upper Crust, Paul H. Wetmore, Charles B. Connor, Sarah E. Kruse, Sean Callihan, Geoffrey Pignotta, Ciprian Stremtan, Andrea Burke Aug 2009

Geometry Of The Trachyte Mesa Intrusion, Henry Mountains, Utah: Implications For The Emplacement Of Small Melt Volumes Into The Upper Crust, Paul H. Wetmore, Charles B. Connor, Sarah E. Kruse, Sean Callihan, Geoffrey Pignotta, Ciprian Stremtan, Andrea Burke

Geology Faculty Publications

The Trachyte Mesa intrusion is one of several small satellite bodies to the larger intrusions of the Henry Mountains, Utah. Most previous studies have worked under the assumptions that Trachyte Mesa is blister shaped and intruded into flat and gently NW dipping strata. In this study we combine structural and geophysical data sets to constrain the structural geology of the host lithologies and the unmodified geometry of the intrusion. Trachyte Mesa intrudes a series of northeast trending upright and open folds formed within the Jurassic Entrada Formation. Truncation of these folds at the contact with the overlying Curtis/Summerville formations indicates …


Researching Nitrite Oxidation At High Temperatures, Dolores A. Huang, Jeremy A. Dodsworth, Brian P. Hedlund Aug 2009

Researching Nitrite Oxidation At High Temperatures, Dolores A. Huang, Jeremy A. Dodsworth, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

15N-nitrate (NO3 -) pool dilution experiments show that ammonia (NH3) is oxidized to nitrate in geothermal springs up to at least 85C; however, nitrite (NO2 -)- oxidizing microorganisms are only known to grow up to 66°C. We hypothesize that thermophilic microorganisms oxidize nitrite to nitrate at high temperatures. Alternatively, it is possible that nitrite is oxidized abiotically. We propose to test these hypotheses by setting up microbial enrichments designed to grow thermophilic nitrite oxidizing bacteria by varying incubation temperature (50, 65, 80°C), oxygen concentration (20% and 5%), and cultivation media. A negative control consisting of filtered spring water (0.1 μm) …


Solar Variability And Climate Processes: The Influence Of Fluctuating Solar Spectral Irradiance On Differential Surface Heating As A Function Of Soil Geochemistry And Radiation Absorption Characteristics, Susan Wahl Aug 2009

Solar Variability And Climate Processes: The Influence Of Fluctuating Solar Spectral Irradiance On Differential Surface Heating As A Function Of Soil Geochemistry And Radiation Absorption Characteristics, Susan Wahl

Theses and Dissertations

The influence of solar variability on climate has received increasing attention. Much of the research has dealt with fluctuating ultraviolet radiation and its effects in the stratosphere; decadal signatures in cloud cover and their relationship to cosmic rays; and correlations of surface air temperature with various proxies (e.g., sunspot numbers; 10Be from ice cores and marine sediments). Much of the research has focused on changing solar radiation within the upper atmosphere and the propagating effects into the troposphere. However, there is a missing component involving differential surface heating as a function of soil composition and corresponding spectral radiation absorption properties …


Paragneiss Zircon Geochronology And Trace Element Geochemistry, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Jian-Xin Zhang, D. K. Bird Jul 2009

Paragneiss Zircon Geochronology And Trace Element Geochemistry, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Jian-Xin Zhang, D. K. Bird

All Faculty Scholarship for the College of the Sciences

In the southeastern part of the North Qaidam terrane, near Dulan, paragneiss hosts minor peridotite and UHP eclogite. Zircon geochronology and trace element geochemistry of three paragneiss samples (located within a ∼3 km transect) indicates that eclogite-facies metamorphism resulted in variable degrees of zircon growth and recrystallization in the three samples. Inherited zircon core age groups at 1.8 and 2.5 Ga suggest that the protoliths of these rocks may have received sediments from the Yangtze or North China cratons. Mineral inclusions, depletion in HREE, and absence of negative Eu anomalies indicate that zircon U-Pb ages of 431 ± 5 Ma …


Anthropogenic Osmium In Rain And Snow Reveals Global-Scale Atmospheric Contamination, Cynthia Chen, Peter N. Sedwick, Mukul Sharma May 2009

Anthropogenic Osmium In Rain And Snow Reveals Global-Scale Atmospheric Contamination, Cynthia Chen, Peter N. Sedwick, Mukul Sharma

Dartmouth Scholarship

Osmium is one of the rarer elements in seawater, with typical concentration of approximately 10 x 10(-15) g g(-1) (5.3 x 10(-14) mol kg(-1)). The osmium isotope composition ((187)Os/(188)Os ratio) of deep oceans is 1.05, reflecting a balance between inputs from continental crust (approximately 1.3) and mantle/cosmic dust (approximately 0.13). Here, we show that the (187)Os/(188)Os ratios measured in rain and snow collected around the world range from 0.16 to 0.48, much lower than expected (>1), but similar to the isotope composition of ores (approximately 0.2) that are processed to extract platinum and other metals to be used primarily …


Coesite In Eclogite From The North Qaidam Mountains And Its Implications, Jian-Xin Zhang, Fan-Cong Meng, Jin-Ping Li, Chris G. Mattinson Mar 2009

Coesite In Eclogite From The North Qaidam Mountains And Its Implications, Jian-Xin Zhang, Fan-Cong Meng, Jin-Ping Li, Chris G. Mattinson

All Faculty Scholarship for the College of the Sciences

Coesite provides direct evidence for ultrahigh pressure metamorphism. Although coesite has been found as inclusions in zircon in paragneiss of the north Qaidam Mountains, it has never been identified in eclogite. In this contribution, based on petrographic observations and in situ Raman microprobe spectroscopy, coesite was identified as inclusions in garnet of eclogite from the Aercituoshan, Dulan UHP metamorphic unit, north Qaidam Mountains. Coesite is partly replaced by quartz, showing a palisade texture. This is the first report on coesite in eclogite from the north Qaidam Mountains, and is also supported by garnet-omphacite-phengite geothermobarometry (2.7–3.25 GPa, 670–730°C). Coesite and its …


Exhumation Of The Inyo Mountains, California: Implications For The Timing Of Extension Along The Western Boundary Of The Basin And Range Province And Distribution Of Dextral Fault Slip Rates Across The Eastern California Shear Zone, Jeffrey Lee, Daniel F. Stockli, Lewis A. Owen, Robert C. Finkel, Roman Kislitsyn Jan 2009

Exhumation Of The Inyo Mountains, California: Implications For The Timing Of Extension Along The Western Boundary Of The Basin And Range Province And Distribution Of Dextral Fault Slip Rates Across The Eastern California Shear Zone, Jeffrey Lee, Daniel F. Stockli, Lewis A. Owen, Robert C. Finkel, Roman Kislitsyn

All Faculty Scholarship for the College of the Sciences

New geologic mapping, tectonic geomorphologic, 10Be terrestrial cosmogenic nuclide, and (U-Th)/He zircon and apatite thermochronometric data provide the first numerical constraints on late Cretaceous to late Quaternary exhumation of the Inyo Mountains and vertical slip and horizontal extension rates across the eastern Inyo fault zone, California. The east-dipping eastern Inyo fault zone bounds the eastern flank of the Inyo Mountains, a prominent geomorphic feature within the western Basin and Range Province and eastern California shear zone. (U-Th)/He zircon and apatite thermochronometry yield age patterns across the range that are interpreted as indicating: (1) two episodes of moderate to rapid …


Riparian And Associated Habitat Characteristics Related To Nutrient Concentrations And Biological Responses Of Small Streams In Selected Agricultural Areas, United States, 2003–04, Ronald B. Zelt, Mark D. Munn Jan 2009

Riparian And Associated Habitat Characteristics Related To Nutrient Concentrations And Biological Responses Of Small Streams In Selected Agricultural Areas, United States, 2003–04, Ronald B. Zelt, Mark D. Munn

United States Geological Survey: Publications

Physical factors, including both in-stream and riparian habitat characteristics that limit biomass or otherwise regulate aquatic biological condition, have been identified by previous studies. However, linking the ecological significance of nutrient enrichment to habitat or landscape factors that could allow for improved management of streams has proved to be a challenge in many regions, including agricultural landscapes, where many ecological stressors are strong and the variability among watersheds typically is large. Riparian and associated habitat characteristics were sampled once during 2003–04 for an intensive ecological and nutrients study of small perennial streams in five contrasting agricultural landscapes across the United …


Cave Minerals Of San Salvador Island, Bahamas, Bogdan P. Onac, Jonathan Sumrall, John E. Mylroie, Joe B. Kearns Jan 2009

Cave Minerals Of San Salvador Island, Bahamas, Bogdan P. Onac, Jonathan Sumrall, John E. Mylroie, Joe B. Kearns

Environmental Sustainability Books

This volume describes the results of a 2009 fieldwork season focusing on the cave minerals found in karst environments throughout San Salvador Island in the Bahamian archipelago. The caves visited represent a sampling of pit and flank margin caves. Each cave description includes a map.


Export Of Terrestrial Dissolved Organic Matter Along A River To Ocean Transect Of The Lower Chesapeake Bay Investigated By Advanced Analytical Techniques, Rachel Leigh Sleighter Jan 2009

Export Of Terrestrial Dissolved Organic Matter Along A River To Ocean Transect Of The Lower Chesapeake Bay Investigated By Advanced Analytical Techniques, Rachel Leigh Sleighter

Chemistry & Biochemistry Theses & Dissertations

Ultrahigh resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proved essential for the complete separation of the thousands of peaks present in natural organic matter (NOM), a complex assemblage of organic molecules present in water, soils, and sediments. An improved understanding of its composition is crucial to understand how pollutants interact with NOM and how NOM cycles through global carbon cycles.

Optimizing the acquisition and handling of the FTICR mass spectra is the first step to obtaining high quality data. A simple method to internally calibrate the peaks in the complex spectra, using naturally present fatty …


Early Neoproterozoic Origin Of The Metazoan Clade Recorded In Carbonate Rock Texture: Reply, Fritz Neuweiler, Elizabeth C. Turner, David J. Burdige Jan 2009

Early Neoproterozoic Origin Of The Metazoan Clade Recorded In Carbonate Rock Texture: Reply, Fritz Neuweiler, Elizabeth C. Turner, David J. Burdige

OES Faculty Publications

We (Neuweiler et al., 2009) used scanning electron microscopic, fluorescence spectroscopic, fluorescence microscopic, and thin-section analytical work from modern, Cretaceous, Silurian, and early Neoproterozoic reefal material to make a geological case for an early Neoproterozoic origin of animals. In a modern analogue for ancient petrographic textures, degradative calcification of the extracellular collagenous matrix (ECM) of a modern siliceous sponge can be directly observed (Neuweiler et al., 2007).


Geochemical Fingerprinting Of Volcanic Airfall Deposits : A Tool In Stratigraphic Correlation, Soumava Adhya Jan 2009

Geochemical Fingerprinting Of Volcanic Airfall Deposits : A Tool In Stratigraphic Correlation, Soumava Adhya

Legacy Theses & Dissertations (2009 - 2024)

Chemical fingerprints of volcanic airfall deposits obtained from high-precision electron microprobe analysis of glass and phenocrysts phases provide geochemical correlations with temporal precision unattainable by other methods. In this research electron microprobe analysis (EMA) techniques, to fingerprint chemically and correlate fresh and altered volcanic airfall deposits, have been utilized to test the value of this tool for future research on stratigraphic correlation. The following samples were chosen from within a variety of sedimentary rocks widely separated spatially and temporally:


Mercury Uptake By Aquatic Macrophytes In Urban And Rural Watersheds, Albany County, Ny, Bernd G. Neumann Jan 2009

Mercury Uptake By Aquatic Macrophytes In Urban And Rural Watersheds, Albany County, Ny, Bernd G. Neumann

Geology Theses and Dissertations

Plants growing in metalliferous soils may restrict metal uptake and transport depending on metal concentration, sediment characteristics, and plant species. As native plants are replaced by invasives, different patterns of metal cycling can occur, making continued study of this process important. Sediments and tissues of four aquatic plant species/genera: Phragmites australis (common reed); Iris versicolor (blueflag iris); Typha latifolia (broadleaf cattail); and genera Cyperus sp. (sedge) from three urban and two rural sites in Albany County, NY were analyzed for total mercury (Hg­T) by cold vapor atomic absorption spectroscopy. Sediments were also measured for organic carbon (OC) by …