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Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio Jan 2008

Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio

OES Faculty Publications

The Southern Ocean exerts a strong impact on marine biogeochemical cycles and global air-sea CO2 fluxes. Over the coming century, large increases in surface ocean CO2 levels, combined with increased upper water column temps. and stratification, are expected to diminish Southern Ocean CO2 uptake. These effects could be significantly modulated by concomitant CO2-dependent changes in the region's biol. carbon pump. Here we show that CO2 concentrations affect the physiology, growth and species composition. of phytoplankton assemblages in the Ross Sea, Antarctica. Field results from in situ sampling and ship-board incubation experiments demonstrate that inorganic …


Integrated Geophysical Imaging Of Subsurface Geologic Conditions Across A Contaminant Plume, Mccracken County, Kentucky, Cora A. Blits Jan 2008

Integrated Geophysical Imaging Of Subsurface Geologic Conditions Across A Contaminant Plume, Mccracken County, Kentucky, Cora A. Blits

University of Kentucky Master's Theses

Over 7.8 km of seismic reflection data and 2 km of electrical resistivity data were acquired, processed, and interpreted during this multi-method geophysical study. Objectives included the definition of geologic conditions underlying a contaminant plume in McCracken County, western Kentucky, and the determination of the potential for structural control on the rate and direction of plume migration. Both geophysical methods indicate the presence of multiple high-angle normal faults outlining a series of asymmetric grabens ranging in width from 160 m to almost 300 m and striking between N40°E and N45°E. There was agreement between the two methods on fault location …


Arctic Perennial Ice Cover Over The Last 14 Million Years, Dennis A. Darby Jan 2008

Arctic Perennial Ice Cover Over The Last 14 Million Years, Dennis A. Darby

OES Faculty Publications

Knowledge of the long-term history of the perennial ice is an important issue that has eluded study because the Cenozoic core material needed has been unavailable until the recent Arctic Coring Expedition (ACEX). Detrital Fe oxide mineral grains analyzed by microprobe from the last 14 Ma (164 m) of the ACEX composite core on the Lomonosov Ridge were matched to circum-Arctic sources with the same mineral and 12-element composition. These precise source determinations and estimates of drift rates were used to determine that these sand grains could not be rafted to the ACEX core site in less than a year. …


Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins Jan 2008

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO2 levels. Rates of N2 and CO2 fixation and growth increased in step with increasing partial pressure of CO2 (pCO2), but only under Fe- replete conditions. N2) and carbon fixation rates at 75 Pa CO2 were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO2 …


Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade Jan 2008

Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade

Masters Theses

"Analysis of geochemistry, mineralogy, total organic content (TOC) and rock evaluation pyrolysis on Woodford Shale well cuttings taken from a horizontal well (Quaid 13-30H) drilled in the Arkoma Basin (Pittsburg County), Oklahoma shows no significant variation in the thermal maturity, type, and/or quantity of organic matter. This is interpreted to mean that the organic matter of the Woodford Shale is relatively homogeneous and has all undergone similar thermal history. In addition, the analysis shows that there are lateral variations in the gas geochemistry in which the shale appears to be broken up into sections, some of which are more enhanced …


The Carbonatite-Hosted Apatite Deposit Of Jacupiranga, Se Brazil: Styles Of Mineralization, Ore Characterization And Association With Mineral Processing, Paula Regina Alves Jan 2008

The Carbonatite-Hosted Apatite Deposit Of Jacupiranga, Se Brazil: Styles Of Mineralization, Ore Characterization And Association With Mineral Processing, Paula Regina Alves

Masters Theses

"The carbonatite-hosted apatite deposit of Jacupiranga is located in southeastern Brazil. The major styles of apatite mineralization are veins or veinlets, small pods or patches, disseminated apatite, and massive aggregates (locally). The concentration of apatite involves grinding of the carbonatite, removal of magnetite with a magnet drum, size classification with cyclones, and flotation to suppress carbonates and collect apatite. Samples of carbonatite were collected from more recent exposures of the mine and drill holes. This study utilized a variety of microscopy methods, namely transmitted and reflected light, cathodoluminescence (CL), and scanning electron microscopy (with wavelength-dispersive spectrometers for mineral compositions)"--Abstract, page …


Physiological Aging Of Potato Tubers Produced During Fall And Spring Growing Seasons And Stored Under Different Temperatures, Dilson A. Bisognin, Sergio T. De Freitas, Auri Brackmann, Jeronimo Luiz Andriolo, Engil Isadora Pujol Pereira, Douglas Renator Muller, Mauricio Guerra Bandinelli Jan 2008

Physiological Aging Of Potato Tubers Produced During Fall And Spring Growing Seasons And Stored Under Different Temperatures, Dilson A. Bisognin, Sergio T. De Freitas, Auri Brackmann, Jeronimo Luiz Andriolo, Engil Isadora Pujol Pereira, Douglas Renator Muller, Mauricio Guerra Bandinelli

School of Earth, Environmental, & Marine Sciences Faculty Publications

Adequate tuber storage is necessary to maintain a good availability of potato tubers in the market and to get seeds with adequate physiological age at planting. The objective of this work was to determine the effect of different storage temperatures on tuber physiological aging of three potato clones produced during fall and spring growing seasons. The experiment was carried out as factorial of three clones (Asterix, SMIJ461-1 and SMINIA793101-3) by four storage temperatures (4, 8, 12 and 25 ºC) and two growing seasons (fall and spring) in a random design with four replications. At 30-day intervals, tubers were evaluated from …


Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler Jan 2008

Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler

School of Earth, Environmental, & Marine Sciences Faculty Publications

The damaging effects of invasive organisms have triggered the development of Invasive Species Predictive Schemes (ISPS). These schemes evaluate biological and historical characteristics of species and prioritize those that should be the focus of exclusion, quarantine, and/or control. However, it is not clear how commonly these schemes take microevolutionary considerations into account. We review the recent literature and find that rapid evolutionary changes are common during invasions. These evolutionary changes include rapid adaptation of invaders to new environments, effects of hybridization, and evolution in recipient communities. Strikingly, we document 38 species in which the specific traits commonly associated with invasive …


Shear Wave Splitting And Mantle Flow Associated With The Deflected Pacific Slab Beneath Northeast Asia, Kelly H. Liu, Stephen S. Gao, Yuan Gao, Jing Wu Jan 2008

Shear Wave Splitting And Mantle Flow Associated With The Deflected Pacific Slab Beneath Northeast Asia, Kelly H. Liu, Stephen S. Gao, Yuan Gao, Jing Wu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A total of 361 SKS and five local S wave splitting measurements obtained at global and regional seismic network stations in NE China and Mongolia are used to infer the characteristics of mantle fabrics beneath northeast Asia. Fast polarization directions at most of the stations in the western part of the study area are found to be consistent with the strike of local geological features. The dominant fast directions at the eastern part, beneath which seismic tomography and receiver function studies revealed a deflected slab in the mantle transition zone (MTZ), are about 100° from north, which are almost exactly …


Using Elliptical Fourier Analysis To Compare Size Of Morphospace Occupation Between Modern Edentulous Freshwater Unionoid Mussels And The Fossils At L6516 (Slope County, North Dakota, Usa), With Remarks On Preservation, Mathew E. Burton-Kelly Jan 2008

Using Elliptical Fourier Analysis To Compare Size Of Morphospace Occupation Between Modern Edentulous Freshwater Unionoid Mussels And The Fossils At L6516 (Slope County, North Dakota, Usa), With Remarks On Preservation, Mathew E. Burton-Kelly

Theses and Dissertations

The purpose of this project was to use outline morphometric techniques to determine the number of freshwater mussel taxa present at locality L6516 (“Das Goods”),which is located in Cretaceous strata in the basal Ludlow Member of the Fort Union Formation in Slope County, North Dakota, U.S.A. Secondary goals were to improve the outline morphometric procedures that have been previously used to characterize fossil and extant freshwater mussels, and to describe in more detail the preservation of the edentulous unionoid specimens from the Das Goods area.

Outlines of individual mussel valves were used for morphometric analyses due to lack of preserved …


Dactyls Reveal Evolutionary Patterns In Decapod Crustaceans, Jeffrey Guy Agnew Jan 2008

Dactyls Reveal Evolutionary Patterns In Decapod Crustaceans, Jeffrey Guy Agnew

LSU Doctoral Dissertations

Because of their high preservation potential and uses in foraging and defense, decapod crustacean dactyls (movable fingers of claws) are potentially excellent test subjects for an ongoing debate concerning the relative importance of top-down (predators) and bottom-up (prey) controls on morphologic diversification and evolution. The utility of dactyls for inferring evolutionary patterns were evaluated using living and subfossil xanthoid crabs sampled from the southeast U.S. Atlantic and Gulf of Mexico coasts, and were used to: (1) distinguish the roles of selection and constraint on dactyl morphology through allometric and shape comparisons in the context of the crab’s phylogenetic relationships and …


Hydrogeochemical Processes As Environmental Indicators In Drip Water: Study Of The Cueva Del Agua (Southern Spain), Angel Fernandez-Cortes, Jose Maria Calaforra, Francisco Sánchez-Martos Jan 2008

Hydrogeochemical Processes As Environmental Indicators In Drip Water: Study Of The Cueva Del Agua (Southern Spain), Angel Fernandez-Cortes, Jose Maria Calaforra, Francisco Sánchez-Martos

International Journal of Speleology

Karst caves exhibit a wide range of hydrological and hydrochemical responses to infiltration events, due to their physical heterogeneity in space and dynamic variability over time, and due to non-Gaussian inputs (rain) and outputs (discharge). This paper reviews different approaches of studying seepage water in caves, in order to understand the infiltration regimen in the non-saturated zone of karst areas. As an illustration, we describe a four-year study of the active carbonate-water system in the Cueva del Agua (Granada, southern Spain) that automatically logs the discharge from a stalactite. The results indicate that: (1) the drip water regime is not …


Contribution Of Artificial Galleries To The Knowledge Of Karstic System Behaviour In Addition To Natural Cavern Data, Benjamin Garry, Thibaut Blondel, Christophe Emblanch, Christophe Sudre, Séverine Bilgot, Alain Cavaillou, Daniel Boyer, Michel Auguste Jan 2008

Contribution Of Artificial Galleries To The Knowledge Of Karstic System Behaviour In Addition To Natural Cavern Data, Benjamin Garry, Thibaut Blondel, Christophe Emblanch, Christophe Sudre, Séverine Bilgot, Alain Cavaillou, Daniel Boyer, Michel Auguste

International Journal of Speleology

The study of karstic systems is mainly based on hydrodynamic and hydrochemical data collected at system inlets (rainfall) and outlets (springs). Indeed, some complementary data base coming from speleological and hydrogeological explorations of natural cavities exist. However, they are not completely representative of all the types of flows. These kinds of flow which have a large part in general hydrodynamics of a system are already the result of a structured organization of karst due to complex phenomena of limestone dissolution. Artificial galleries have the advantage to be easily accessible. Moreover, they cut randomly flows which are much less structured or …


Nutrient And Carbon Dynamics In The Chesapeake Bay Outflow Plume And Their Effect On The Coastal Ocean Environment, Katherine C. Filippino Jan 2008

Nutrient And Carbon Dynamics In The Chesapeake Bay Outflow Plume And Their Effect On The Coastal Ocean Environment, Katherine C. Filippino

OES Theses and Dissertations

Seasonally resolved nutrient and carbon fluxes from estuaries to the coastal ocean are poorly constrained. Nutrient and carbon cycling in highly productive regions like the Chesapeake Bay outflow plume and surrounding coastal environments greatly affect our global understanding of carbon cycling. The overall questions for the research described in this dissertation stem from the need to close global carbon budgets, and obtain a fundamental understanding of nutrient dynamics in a coastal region heavily influenced by seasonality and human impacts.

Within the framework of physical characteristics of the outflow plume and through the characterization of nutrient concentrations, primary productivity rates, and …


The Origin Of The Bemaraha Tsingy (Madagascar), Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer Jan 2008

The Origin Of The Bemaraha Tsingy (Madagascar), Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer

International Journal of Speleology

On Madagascar the most representative occurrences of tsingy are at Ankarana and Bemaraha. The tsingy are built up of giant grikes developed along cracks as well as karren features of much smaller size which cover the surfaces between grikes. We investigated the Bemaraha tsingy of Madagascar (surveyed profiles, measured grike directions, etc.) in order to reconstruct their development. The observations indicate that the majority of grikes of the tsingy are created from caves formed under the karst water table and subsequently opened up to the surface. The predominant processes may have been downward progressing dissolution or the collapse of cave …


Surface Corrosion Of An Alpine Karren Field: Recent Measures At Innerbergli (Siebenhengste, Switzerland), Philipp Häuselmann Jan 2008

Surface Corrosion Of An Alpine Karren Field: Recent Measures At Innerbergli (Siebenhengste, Switzerland), Philipp Häuselmann

International Journal of Speleology

29 year old rock paintings in the Alpine karren field of Innerbergli (Siebenhengste, Switzerland) prevented the underlying rock from corrosion, while the surface nearby was corroded. Measurement of the steps indicates an average recent corrosion rate of 0.014 (±0.007) mm/a. This denudation rate is very similar to those observed in other comparable places and with other means.


An Investigation Of Meromixis In Cave Pools, Lechuguilla Cave, New Mexico, David B. Levy Jan 2008

An Investigation Of Meromixis In Cave Pools, Lechuguilla Cave, New Mexico, David B. Levy

International Journal of Speleology

Chemical characteristics of permanent stratification in cave pools (meromixis) may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically < 1 mg L-1), biogenic meromixis resulting in O2(g)-depleted subsurface waters is not expected. Four pools at various depths below ground surface (0 m) were studied: (1) …


Annually Laminated Speleothems: A Review, Andy Baker, Claire L. Smith, Catherine Jex, Ian J. Fairchild, Dominique Genty, Lisa Fuller Jan 2008

Annually Laminated Speleothems: A Review, Andy Baker, Claire L. Smith, Catherine Jex, Ian J. Fairchild, Dominique Genty, Lisa Fuller

International Journal of Speleology

This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.


Monitoring Climatological, Hydrological And Geochemical Parameters In The Père Noël Cave (Belgium): Implication For The Interpretation Of Speleothem Isotopic And Geochemical Time-Series, Sophie Verheyden, Dominique Genty, Guy Deflandre, Yves Quinif, Eduard Keppens Jan 2008

Monitoring Climatological, Hydrological And Geochemical Parameters In The Père Noël Cave (Belgium): Implication For The Interpretation Of Speleothem Isotopic And Geochemical Time-Series, Sophie Verheyden, Dominique Genty, Guy Deflandre, Yves Quinif, Eduard Keppens

International Journal of Speleology

Père Noël cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (δ18O, δ13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (δ18O and …


A Study Of Land Surface Processes Using Land Surface Models Over The Little River Experimental Watershed, A. K. Sahoo, P. A. Dirmeyer, P. R. Houser, Menas Kafatos Jan 2008

A Study Of Land Surface Processes Using Land Surface Models Over The Little River Experimental Watershed, A. K. Sahoo, P. A. Dirmeyer, P. R. Houser, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Three different land surface models (Hydrological improvements to the Simplified version of the Simple Biosphere model (HySSiB), Noah model, and Community Land Model (CLM)) were simulated on the NASA Goddard Space Flight Center’s Land Information System platform at 1-km resolution over the Little River Experimental Watershed, Georgia, and the simulated results were analyzed to address the local-scale land-atmosphere processes. All the three models simulated the soil moisture in space and time realistically. The Noah model produced higher soil moisture whereas the CLM got lower soil moisture with many dry down phases. CLM and HySSiB models were oversensitive to the atmospheric …


Stable Isotope Analysis Of Upper Tithonian Limestones With Dinosaur Footprints From Kirmenjak Quarry (Istria, Croatia), Blanka Cvetko Tešović, Aleksandar Mezga, Bosiljka Glumac Jan 2008

Stable Isotope Analysis Of Upper Tithonian Limestones With Dinosaur Footprints From Kirmenjak Quarry (Istria, Croatia), Blanka Cvetko Tešović, Aleksandar Mezga, Bosiljka Glumac

Geosciences: Faculty Publications

The Kirmenjak locality of western Istria, Croatia, represents the oldest evidence of a dinosaur presence on the Adriatic-Dinaridic Carbonate Platform (ADCP). In a quarry at this locality, almost a thousand sauropod footprints are recognized in one distinctive trackbearing horizon within the Upper Tithonian limestones. The stable isotopes of oxygen and carbon, in conjunction with microfacies analysis of carbonate rocks exposed in this quarry, unravel details about the marginal marine or coastal environments in which sauropods left their footprints. Rocks from the trackbearing horizon, and laterally adjacent area, represent intertidal fenestral mudstones that form the top of a shallowing-upward succession, capped …


Fossil Palm Frond And Tree Trunk Molds: Occurrence And Implications For Interpretation Of Bahamian Quaternary Carbonate Eolianites, H. Allen Curran, Mark A. Wilson, John E. Mylroie Jan 2008

Fossil Palm Frond And Tree Trunk Molds: Occurrence And Implications For Interpretation Of Bahamian Quaternary Carbonate Eolianites, H. Allen Curran, Mark A. Wilson, John E. Mylroie

Geosciences: Faculty Publications

Molds of palm fronds and vertical, cylindrical structures interpreted as molds of palm tree trunks were reported from Holocene and upper Pleistocene carbonate eolianites on several islands in the Bahamas in the early 1990s. As a result of recent discoveries described herein, palm frond and tree trunk molds are now known to be widespread in Bahamian eolianites, including Holocene beds on Cat Island, Eleuthera, Lee Stocking Island of the Exuma Cays, Long Island, and Stocking Island offshore from Georgetown, Exuma. Late Pleistocene occurrences are known from Eleuthera, Long Island, Norman's Pond Cay of the Exuma Cays, and San Salvador Island. …


Multiple Sedimentary Sequences, Bird Tracks And Lagoon Beaches In Last Interglacial Oolites, Boiling Hole, North Eleuthera Island, Bahamas, Pascal Kindler, H. Allen Curran, Damiel Marty, Elias Samankassou Jan 2008

Multiple Sedimentary Sequences, Bird Tracks And Lagoon Beaches In Last Interglacial Oolites, Boiling Hole, North Eleuthera Island, Bahamas, Pascal Kindler, H. Allen Curran, Damiel Marty, Elias Samankassou

Geosciences: Faculty Publications

Our review of the last interglacial (Marine Isotope Stage 5e) stratigraphic record from the Boiling Hole exposure in northern Eleuthera Island, Bahamas, revealed the occurrence of two vertically stacked shallowing-upward sequences of oolitic coastal deposits showing beach facies at about 3 and 6 m above mean sea level, respectively. These beach strata dip towards the bank interior and the upper one includes a paleosurface on top of an oolitic grainstone bed with a 2-m-long bird trackway. These fossil beaches correspond to two distinctive sea-level highstands during the last interglacial that could have possibly reached +5 and +8 m above modem …


Geochemical Analysis Of Ironstone Preserved Molluscan Fossils Of The Hell Creek Formation (Cretaceous) And Ludlow Member Of The Fort Union Formation (Paleogene) Of Southwestern North Dakota, Tanya P. Justham Jan 2008

Geochemical Analysis Of Ironstone Preserved Molluscan Fossils Of The Hell Creek Formation (Cretaceous) And Ludlow Member Of The Fort Union Formation (Paleogene) Of Southwestern North Dakota, Tanya P. Justham

Theses and Dissertations

The uppermost Cretaceous Hell Creek Formation and Paleocene Ludlow Member of the Fort Union Formation in easternmost Montana and western North Dakota produce ironstone preserved freshwater molluscan fossils. Ironstone preserved mollusks are associated with ironstone nodules, which have been described as composed of iron carbonate, iron oxide, or manganese oxide by various researchers. To date, the exact composition of the ironstone preservation has not been satisfactorily determined to allow agreement between researchers. Freshwater mollusk fossils, preserved as ironstone external casts, molds, and steinkerns, tend to be highly weathered. The poor preservation of the fossils has resulted in little professional interest, …


Electron Donor Potential Of Eastern North Dakota Shale Formations, Ryan J. Salinas Klapperich Jan 2008

Electron Donor Potential Of Eastern North Dakota Shale Formations, Ryan J. Salinas Klapperich

Theses and Dissertations

Research involving a network of in situ mesocosms (ISM) in North Dakota, Minnesota, and Iowa has revealed significant variation in the denitrification capacity of aquifers in different regions of these states. One aquifer in particular, the Elk Valley Aquifer (EVA) of east-central North Dakota, has the highest concentrations of electron (e) donors (organic carbon -0.4%, pyrite as S -0.4%, and ferrous iron -0.3%) within its sediments and the highest rates of denitrification. The sediments at all of the ISM sites were deposited as outwash during the last Wisconsinan glaciation (-12ka), yet their e· donor concentrations vary. I suggest that the …


Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan Jan 2008

Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan

Theses and Dissertations

The concentrations of electron donors in aquifer sediments are important in understanding the fate and transport of redox-sensitive constituents in ground water, such as nitrate. In this study, 50 sediment samples were collected from below the water table from 11 boreholes at the US Geological Survey Agricultural Chemicals Transport site near New Providence, Iowa. All samples were analyzed for gravel, sand (coarse, medium, and fine), silt, clay, inorganic carbon contents and for the following electron donors: organic carbon, ferrous iron, and inorganic sulfide. A subset of sediment samples was analyzed for organic sulfur, but all of the 14 samples were …


Textural Analysis Of A Rhyolite Dike Of The Southern Oklahoma Aulacogen At Medicine Park, Oklahoma, Sean Patrick O'Donnell Jan 2008

Textural Analysis Of A Rhyolite Dike Of The Southern Oklahoma Aulacogen At Medicine Park, Oklahoma, Sean Patrick O'Donnell

Masters Theses

"Detailed analysis of the modal abundance and crystal size distribution (CSD) of glomerocrystic quartz and alkali feldspar phenocrysts in a porphyritic "rhyolite" dike at Medicine Park, Oklahoma were integrated with known phase relationships in the system SiO₂-NaAlSi₃O₈-KAlSi₃-O₈-H₂O to constrain the history of this intrusion"--Abstract, page iv.


Massive Spatiotemporal Watershed Hydrological Storm Event Response Model (Mhserm) With Time-Lapsed Nexrad Radar Feed, Changqing Song Jan 2008

Massive Spatiotemporal Watershed Hydrological Storm Event Response Model (Mhserm) With Time-Lapsed Nexrad Radar Feed, Changqing Song

Civil & Environmental Engineering Theses & Dissertations

Correctly and efficiently estimating hydrological responses corresponding to a specific storm event at the streams in a watershed is the main goal of any sound water resource management strategy. Methods for calculating a stream flow hydrograph at the selected streams typically require a great deal of spatial and temporal watershed data such as geomorphological data, soil survey, landcover, precipitation data, and stream network information to name a few. However, extracting and preprocessing such data for estimation and analysis is a hugely time-consuming task, especially for a watershed with hundreds of streams and lakes and complicated landcover and soil characteristics. To …


Introduction To Special Section On Microcosms In Ice: The Biogeochemistry Of Cryoconite Holes, Andrew G. Fountain, Martyn Tranter Jan 2008

Introduction To Special Section On Microcosms In Ice: The Biogeochemistry Of Cryoconite Holes, Andrew G. Fountain, Martyn Tranter

Geology Faculty Publications and Presentations

Cryoconite holes are small, water filled, cylindrical melt-holes on glacial ice surface. Cryoconite, 'cold dust,' refers to the thin layer of sediment at the hole bottom. The holes form from surficial sediment patches that absorbs more solar radiation than the surrounding ice and which preferentially melt into the glacier forming a cylindrical water-filled hole. These holes form on the ice-covered, as opposed to snow covered, parts of glaciers world-wide, wherever there is sufficient energy for melting. Biogeochemically, cryoconite holes are interesting because the sediment is inncoculated with biologic material, a fraction of which thrives in the cryoconite environment of near-freezing …


Water Centrality For Water And Society, Ute Goeft Jan 2008

Water Centrality For Water And Society, Ute Goeft

Theses: Doctorates and Masters

The current approach to water management in Western societies, including Australia, is based on allocating water between different users. Appropriate for commercial uses, this commodity view of water has proved difficult for the inclusion of environmental and social concerns. Issues, such as which aspects have precedence, how much water should be allocated to each and how to make trade-offs in cases of insufficient water, pose problems that are yet to be worked out. In addition, there is a lack of knowledge regarding the identification of environmental as well as social water needs. The latter has prompted the writing of this …