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Articles 91 - 120 of 537
Full-Text Articles in Earth Sciences
Quarternary Alluvial Deposition In The Upper Green River Valley, Kentucky, Juan Herrera
Quarternary Alluvial Deposition In The Upper Green River Valley, Kentucky, Juan Herrera
Masters Theses & Specialist Projects
This research describes the alluvial deposits and Quaternary geomorphic evolution of the Upper Green River in Kentucky by documenting the nature of flood plain sediments at two sites along the valley bottom of the Upper Green River between Mammoth Cave National Park and Green River Lake. Field methods employed included stratigraphic descriptions of bank exposures and borings obtained in flood plain surfaces, along with textural and radiocarbon analysis of sediment samples. Sediment samples from boreholes and bank exposures in two study sites (Pitman Creek confluence, -PCC- and Upper Green River Biological Preserve -UGRBP-) were collected and sieved to determine grain …
Geostatistical And Stochastic Study Of Flow And Tracer Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Feng Pan, Xiaolong Bill Hu, Jianting Zhu, Amy J. Smiecinski
Geostatistical And Stochastic Study Of Flow And Tracer Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Feng Pan, Xiaolong Bill Hu, Jianting Zhu, Amy J. Smiecinski
Publications (YM)
Yucca Mountain has been proposed by the U.S. Department of Energy as the nation’s long-term, permanent geologic repository for spent nuclear fuel or high-level radioactive waste. The potential repository would be located in Yucca Mountain’s unsaturated zone (UZ), which acts as a critical natural barrier delaying arrival of radionuclides to the water table. Since radionuclide transport in groundwater can pose serious threats to human health and the environment, it is important to understand how much and how fast water and radionuclides travel through the UZ to groundwater. The UZ system consists of multiple hydrogeologic units whose hydraulic and geochemical properties …
Assessment Of Undiscovered Oil And Gas Resources In Tertiary Strata Of The Gulf Coast, 2007
Assessment Of Undiscovered Oil And Gas Resources In Tertiary Strata Of The Gulf Coast, 2007
United States Geological Survey: Publications
Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 113.7 trillion cubic feet of undiscovered natural gas, a mean of 690 million barrels of undiscovered oil, and a mean of 3.7 billion barrels of undiscovered natural gas liquids in onshore lands and State waters of the Gulf Coast.
Microbial Nitrogen Limitation Increases Decomposition, Joseph M. Craine, Carl Morrow, Noah Fierer
Microbial Nitrogen Limitation Increases Decomposition, Joseph M. Craine, Carl Morrow, Noah Fierer
Dartmouth Scholarship
With anthropogenic nutrient inputs to ecosystems increasing globally, there are long-standing, fundamental questions about the role of nutrients in the decomposition of organic matter. We tested the effects of exogenous nitrogen and phosphorus inputs on litter decomposition across a broad suite of litter and soil types. In one experiment, C mineralization was compared across a wide array of plants individually added to a single soil, while in the second, C mineralization from a single substrate was compared across 50 soils. Counter to basic stoichiometric decomposition theory, low N availability can increase litter decomposition as microbes use labile substrates to acquire …
Bedrock Channel Geometry Along An Orographic Rainfall Gradient In The Upper Marsyandi River Valley In Central Nepal, William Craddock, Douglas Burbank, Bodo Bookhagen, Emmanuel Gabet
Bedrock Channel Geometry Along An Orographic Rainfall Gradient In The Upper Marsyandi River Valley In Central Nepal, William Craddock, Douglas Burbank, Bodo Bookhagen, Emmanuel Gabet
Faculty Publications
Pronounced rainfall gradients combined with spatially uniform exhumation of rocks at Quaternary timescales and uniform rock strength make the upper Marsyandi River valley in central Nepal a useful natural laboratory in which to explore variations in bedrock channel width. We focus on small catchments (0.6–12.4 km2) along a more than tenfold gradient in monsoon rainfall. Rainfall data are gathered from a dense weather network and calibrated satellite observations, the pattern of Quaternary exhumation is inferred from apatite fission track cooling ages, and rock compressive strength is measured in the field. Bedrock channel widths, surveyed at high scour indicators, scale as …
Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake
Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake
Sheep Updates
This session covers seven papers from different authors:
PROFITABILITY
1. Benchmarking demonstrates both the potential and realised productivity gains in the sheep and wool industry, Andrew Ritchie, Edward Riggall and James Hall, ICON Agriculture, Darkan
2. Improving sheep genetics will increase farm profitability, Gus Rose, Johan Greeff Department of Agriculture and Food Western Australia, John Young Farming Systems Analysis Service, WA
3. Meat, Merinos and making money in WA Pastoral Zone, M. Alchin, M. Young and T. Johnson, Department of Agriculture and Food Western Australia,
GRAZING
4. Nitrogen - farmers' friend or foe? John Lucy and Martin Staines, Department …
Cost/Effectiveness Analysis Of Obtaining Operational Estimates Of Reference Evapotranspiration, Peninsular Florida, Usa, Michael G. Kittridge
Cost/Effectiveness Analysis Of Obtaining Operational Estimates Of Reference Evapotranspiration, Peninsular Florida, Usa, Michael G. Kittridge
USF Tampa Graduate Theses and Dissertations
The objective of this study is to conduct a cost/effectiveness analysis of the computation of reference evapotranspiration (ETo) in the peninsular of Florida. A meteorological station on the Fort Meade Mine in Polk County, Florida was used to provide data for the calculation of ETo. Five ETo equations were tested to determine the accuracy and cost/effectiveness to the fully measured ASCE Penman-Monteith (Full ASCE-PM) equation on daily, monthly, and annually time steps. The ETo equations ranged in amounts of parameters from the Full ASCE-PM to the Hargreaves. The energy terms accounted for approximately 90% of the total ETo flux. Solar …
Seismic And Well Log Attribute Analysis Of The Jurassic Entrada/Curtis Interval Within The North Hill Creek 3d Seismic Survey, Uinta Basin, Utah, A Case History, Ryan J. Oneal
Theses and Dissertations
3D seismic attribute analysis of the Jurassic Entrada/Curtis interval within the North Hill Creek (NHC) survey has been useful in delineating reservoir quality eolian-influenced dune complexes. Amplitude, average reflection strength and spectral decomposition appear to be most useful in locating reservoir quality dune complexes, outlining their geometry and possibly displaying lateral changes in thickness. Cross sectional views displaying toplap features likely indicate an unconformity between Entrada clinoforms below and Curtis planar beds above. This relationship may aid the explorationist in discovering this important seismic interval. Seismic and well log attribute values were cross plotted and have revealed associations between these …
Microfacies Analysis, Sedimentary Petrology, And Reservoir Characterization Of The Sinbad Limestone Based Upon Surface Exposures In The San Rafael Swell, Utah, Caleb R. Osborn
Theses and Dissertations
The Lower Triassic Sinbad Limestone Member of the Moenkopi Formation has produced minor amounts of oil in the Grassy Trail Creek field near Green River, Utah and is present below much of central Utah including the recently discovered Covenant field. Superb outcrops of this thin (15 m), mixed carbonate-silicilastic unit in the San Rafael Swell permit detailed analysis of its vertical and lateral reservoir heterogeneity. Vertically, the Sinbad Limestone comprises three facies associations: (A) a basal storm-dominated, well-circulated skeletal-oolitic-peloidal limestone association, (B) a storm-dominated, poorly-circulated hummocky cross-stratified siliciclastic/peloidal association, and (C) a capping peritidal cross-bedded oolitic dolograinstone association. Eleven microfacies …
Transient Storage As A Function Of Geomorphology, Discharge, And Permafrost Active Layer Conditions In Arctic Tundra Streams, Jay P. Zarnetske, Michael N. Gooseff, Troy R. Brosten, John H. Bradford, James P. Mcnamara, W. Breck Bowden
Transient Storage As A Function Of Geomorphology, Discharge, And Permafrost Active Layer Conditions In Arctic Tundra Streams, Jay P. Zarnetske, Michael N. Gooseff, Troy R. Brosten, John H. Bradford, James P. Mcnamara, W. Breck Bowden
CGISS Publications and Presentations
Transient storage of solutes in hyporheic zones or other slow-moving stream waters plays an important role in the biogeochemical processes of streams. While numerous studies have reported a wide range of parameter values from simulations of transient storage, little field work has been done to investigate the correlations between these parameters and shifts in surface and subsurface flow conditions. In this investigation we use the stream properties of the Arctic (namely, highly varied discharges, channel morphologies, and subchannel permafrost conditions) to isolate the effects of discharge, channel morphology, and potential size of the hyporheic zone on transient storage. We repeated …
The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter
The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter
Theses and Dissertations
Metallic bronze-Co-Ag alloys ranging from1-90 µm have been discovered in bomb and lava vesicles from the mafic volcanoes of Kilauea in Hawaii and Vesuvius, Stromboli and Etna in Italy. It is inferred that the metals for these alloys were transported (in part) as chloride complexes, and that the metal ratios in the alloys may be a function of S/Cl. Alloy compositions in each system are extremely heterogeneous with Co concentrations from 1% to 94%, Cu from 2% to 89%, Sn from 1% to 22% and Ag from 0.5% to 42%. Maximum abundances (in wt%) of other trace or minor elements …
Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple
Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple
Theses and Dissertations
Reservoir heterogeneity plays an important role in oil field economics and completion strategies. We herein characterize the reservoir heterogeneity of the Early Jurassic Navajo Sandstone in the Justensen Flat/Devils Canyon area of the San Rafael Swell, Utah. These outcrops are located approximately 60 kilometers (45 mi) east of the recently discovered Covenant oil field which is located in the central Utah thrust belt exploration play. The reservoir for the Covenant field is the Navajo Sandstone. This study can serve as an outcrop analogue for this developing play and other eolian reservoirs worldwide. There are eight facies within the Navajo Sandstone …
Incorporating Results Of Avian Toxicity Tests Into A Model Of Annual Reproductive Success, Richard S. Bennett*, Matthew A. Etterson
Incorporating Results Of Avian Toxicity Tests Into A Model Of Annual Reproductive Success, Richard S. Bennett*, Matthew A. Etterson
United States Environmental Protection Agency: Publications
Modeling the effects of pesticide exposure on avian populations requires knowledge of how the pesticide changes survival and fecundity rates for the population. Although avian reproduction tests are the primary source of information on reproductive effects in the pesticide risk assessment process, current tests cannot provide a direct estimate of the effects of a pesticide on fecundity rates. We present a mathematical model that integrates information on specific types of effects from reproduction tests with information on avian life history parameters, the timing of pesticide applications, and the temporal pattern of pesticide exposure levels to estimate pesticide effects on annual …
Droughtscape, Summer 2007, National Drought Mitigation Center
Droughtscape, Summer 2007, National Drought Mitigation Center
DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)
Summer 07 Outlook
Hayes Named Director of NDMC
NDMC & UN Plan for Drought
Book Review: The Worst Hard Time
Drought Tools Workshops Underway
U.S. Drought Monitor Forum October 10-11, 2007 Portland, Oregon
Evaluation Of An Experimental Lidar For Surveying A Shallow, Braided, Sand-Bedded River, Paul J. Kinzel, C. Wayne Wright, Jonathan M. Nelson, Aaron R. Burman
Evaluation Of An Experimental Lidar For Surveying A Shallow, Braided, Sand-Bedded River, Paul J. Kinzel, C. Wayne Wright, Jonathan M. Nelson, Aaron R. Burman
United States Geological Survey: Staff Publications
Reaches of a shallow (<1.0 m), braided, sand-bedded river were surveyed in 2002 and 2005 with the National Aeronautics and Space Administration’s Experimental Advanced Airborne Research LiDAR (EAARL) and concurrently with conventional survey-grade, real-time kinematic, global positioning system technology. The laser pulses transmitted by the EAARL instrument and the return backscatter waveforms from exposed sand and submerged sand targets in the river were completely digitized and stored for postflight processing. The vertical mapping accuracy of the EAARL was evaluated by comparing the ellipsoidal heights computed from ranging measurements made using an EAARL terrestrial algorithm to nearby (<0.5 m apart) ground-truth ellipsoidal heights. After correcting for apparent systematic bias in the surveys, the root mean square error of these heights with the terrestrial algorithm in the 2002 survey was 0.11 m for the 26 measurements taken on exposed sand and 0.18 m for the 59 measurements taken on submerged sand. In the 2005 survey, the root mean square error was 0.18 m for 92 measurements taken on exposed sand and 0.24 m for 434 measurements on submerged sand. In submerged areas the waveforms were complicated by reflections from the surface, water column entrained turbidity, and potentially the riverbed. When applied to these waveforms, especially in depths greater than 0.4 m, the terrestrial algorithm calculated the range above the riverbed. A bathymetric algorithm has been developed to approximate the position of the riverbed in these convolved waveforms and preliminary results are encouraging.
Effect Of Regional Tectonic Setting On Local Fault Response To Episodes Of Volcanic Activity, Diana C. Roman, Philip Heron
Effect Of Regional Tectonic Setting On Local Fault Response To Episodes Of Volcanic Activity, Diana C. Roman, Philip Heron
Geology Faculty Publications
In this study we examine the interaction of tectonic and volcanically-generated stress fields, and their combined effect on patterns of volcanotectonic (VT) seismicity, by calculating Coulomb stress changes on local faults induced by a constant dike inflation event in a background stress field of systematically varying magnitude and orientation. We find that patterns of VT seismicity (earthquake locations and fault-plane solutions) resulting from dike inflation depend strongly on the relative strength and orientation of background tectonic stresses. Patterns of VT seismicity similar to those predicted by our Coulomb stress models have been observed at several recently active volcanoes, and appear …
Pend Oreille River, Box Canyon Model: Model Scenario Simulations, Chris Berger, Robert Leslie Annear, Scott A. Wells
Pend Oreille River, Box Canyon Model: Model Scenario Simulations, Chris Berger, Robert Leslie Annear, Scott A. Wells
Civil and Environmental Engineering Faculty Publications and Presentations
The Washington Department of Ecology is interested in developing a temperature Total Maximum Daily Load (TMDL) allocation for the Pend Oreille River between the Albeni Falls Dam (U.S. Army Corps of Engineer’s reservoir) and Box Canyon Dam as shown in Figure 1. The Pend Oreille drainage basin is shown in Figure 2. An existing model of the Box Canyon reach was updated from CE-QUALW2 Version 3.0 to Version 3.5. This current research involves improving the calibration of the original model (1997 and 1998) and expanding the model using 2004 as an additional data set for calibration.
The use of field …
Cave Development In Strata Of Ordovician-And Silurian-Devonian-Age In Highland County, Virginia, Carol Ann Peterson
Cave Development In Strata Of Ordovician-And Silurian-Devonian-Age In Highland County, Virginia, Carol Ann Peterson
OES Theses and Dissertations
Picturesque Highland County, Virginia, also known as "Virginia's Little Switzerland", is characterized by high mountains, tranquil rivers, and hundreds of caves. This study determines how geologic structures and processes control speleogenesis, or cave development, in the county. Solutional caves in Highland County are found in Ordovician limestones and dolostones and in Silurian- to Devonian-age limestones. Despite the lithologic and structural differences between the strata, caves in both sections tend to be similarly joint-controlled in directions of both regional strike (N40°E), dip (northwest or southeast), or in fractures intersecting at 60 and/or 120 degrees. Brittle failure, including fractures and faults induced …
Condensed And Expanded Sections In The Lower Mesaverde Clastic Wedge, Campanian Of Wyoming: Evidence For Tectonic Rectification Of Sea Level, Matthew W. Botzler
Condensed And Expanded Sections In The Lower Mesaverde Clastic Wedge, Campanian Of Wyoming: Evidence For Tectonic Rectification Of Sea Level, Matthew W. Botzler
OES Theses and Dissertations
The stratigraphy of the Cretaceous Western Interior basin indicates that sea level oscillated during the late Cretaceous. The oscillations were polyharmonic, with periods ranging from millions of years to hundred thousands and ten thousands of years. However, there is disagreement over the extent to which sea level change was global in nature and the extent to which it was driven by local uplift or subsidence (tectonism). In orogenic regions where subsidence, sediment supply, and eustatic variation are all affecting sea level, comparisons of high and low frequency cycles can help to sort out forcing mechanisms. Low frequency eustatic sea level …
Two Modes Of Accelerated Glacier Sliding Related To Water, Joel T. Harper, Neil Humphrey, W. T. Pfeffer, Brian Lazar
Two Modes Of Accelerated Glacier Sliding Related To Water, Joel T. Harper, Neil Humphrey, W. T. Pfeffer, Brian Lazar
Geosciences Faculty Publications
We present the first glacier-wide detailed measurement of basal effective pressure and related observations including bed separation to elucidate the role of water in sliding. The hard bedded glacier instrumented in our study exhibited two phases of accelerated sliding motion apparently driven by separate mechanisms. The first acceleration phase (up to 5 fold increase in speed) was closely tied to an increase in bed separation. The faster second phase (up to 9 fold increase in speed) was related to an unusually high level of connectivity of subglacial waters. We infer the first mode was related to cavity opening and the …
Hydrostratigraphy And Groundwater Migration Within Surficial Deposits At The North Lakes Wetland, Hillsborough County, Florida, Jason J. Laroche
Hydrostratigraphy And Groundwater Migration Within Surficial Deposits At The North Lakes Wetland, Hillsborough County, Florida, Jason J. Laroche
USF Tampa Graduate Theses and Dissertations
A wetland in west-central Florida was studied to characterize the local hydrostratigraphic configuration of surficial deposits overlying more-permeable limestones and conceptualize groundwater recharge. Eight continuous cores were drilled through the surficial deposits and partially into the underlying limestone. A total of 111 samples were extracted from the cores for laboratory sediment analyses and testing. The surficial deposits are roughly eight meters thick and made up of upper and lower clean-sand hydrostratigraphic layers (S1 and S3, respectively) separated by a low-permeability layer of clayey sand (S2). Also, a discontinuous low-permeability layer of clayey sand (S4) lies between S3 and the top …
A 2650-Year-Long Record Of Environmental Change From Northern Yellowstone National Park Based On A Comparison Of Multiple Proxy Data, Cathy Whitlock, Walter Dean, Joseph Rosenbaum, Lora Stevens, Sherilyn C. Fritz, Brandi Bracht, Mitchell Power
A 2650-Year-Long Record Of Environmental Change From Northern Yellowstone National Park Based On A Comparison Of Multiple Proxy Data, Cathy Whitlock, Walter Dean, Joseph Rosenbaum, Lora Stevens, Sherilyn C. Fritz, Brandi Bracht, Mitchell Power
Department of Earth and Atmospheric Sciences: Faculty Publications
Geochemical, stable-isotope, pollen, charcoal, and diatom records were analyzed at high-resolution in cores obtained from Crevice Lake, a varved-sediment lake in northern Yellowstone National Park. The objective was to reconstruct the ecohydrologic, vegetation, and fire history of the watershed for the last 2650 years to better understand past climate variations at the forest-steppe transition. The data suggest a period of limited bottom-water anoxia, relatively wet winters, and cool springs and summers from 2650 to 2100 cal yrBP (700–150 BC). Dry warm conditions occurred between 2100 and 850–800 cal yrBP (150 BC and AD 1100–1150), when the lake was anoxic, winter …
Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen
Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen
Geology Faculty Publications
Trace element and Sr-Nd-Pb isotope compositions of basaltic lavas from 11 volcanoes spanning 1300 km of the Aleutian Island arc provide new constraints on the recycling of elements in melts and fluids derived from subducted oceanic crust and sediment. Despite a nearly twofold variation in the flux of sediment subducted along the Aleutians, proxies indicating the presence of sediment melt in the magma source, including Th/La and Th/Nd, do not vary systematically along strike. In contrast, ratios including B/La, B/Nb, B/Be, Cs/La, Pb/Ce, and Li/Y suggest that the quantity or composition of fluid transferred from the slab into the mantle …
Evaluating Discontinuities In Complex Systems: Toward Quantitative Measures Of Resilience, Craig Stow, Craig R. Allen, Ahjond S. Garmestani
Evaluating Discontinuities In Complex Systems: Toward Quantitative Measures Of Resilience, Craig Stow, Craig R. Allen, Ahjond S. Garmestani
United States Geological Survey: Staff Publications
The textural discontinuity hypothesis (TDH) is based on the observation that animal body mass distributions exhibit discontinuities that may reflect the texture of the landscape available for exploitation. This idea has been extended to other complex systems, hinting that the identification and quantification of discontinuities in the distributions of appropriate variables may provide clues to emergent system properties such as resilience. We propose a discontinuity index, based on the vector norm of the full assemblage of observed discontinuities, as a means to quantify and compare this characteristic among systems. We also evaluate four methods to identify the number and location …
Strain And Rotation Rate From Gps In Tibet, Anatolia, And The Altiplano, Richard W. Allmendinger, Robert Reilinger, John P. Loveless
Strain And Rotation Rate From Gps In Tibet, Anatolia, And The Altiplano, Richard W. Allmendinger, Robert Reilinger, John P. Loveless
Geosciences: Faculty Publications
Deformation measured by regional GPS networks in continental plateaus reflects the geologic and tectonic variability of the plateaus. For two collisional plateaus (Tibet and Anatolia) and one noncollisional (the Altiplano), we analyze the regional strain and rotation rate by inverting GPS velocities to calculate the full two-dimensional velocity gradient tensor. To test the method, we use gridded velocities determined from an elastic block model for the eastern Mediterranean/Middle East region and show that to a first order, the deformation calculated directly from the GPS vectors provides an accurate description of regional deformation patterns. Principal shortening and extension rate axes, vertical …
Dendrochronological Analysis Of Oak (Quercus) Tree Cross-Sections From The Victor Crouso Field, Wayne County, Ohio
Historic Structures
Dating historical structures in Wayne County, Ohio using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Belding, Elyssa; Wiles, Greg
Mapping Middle Paleozoic Erosional And Karstic Patterns With 3-D Seismic Attributes And Well Data In The Arkoma Basin, Oklahoma, Alonzo R. Brinkerhoff
Mapping Middle Paleozoic Erosional And Karstic Patterns With 3-D Seismic Attributes And Well Data In The Arkoma Basin, Oklahoma, Alonzo R. Brinkerhoff
Theses and Dissertations
Newly available industry well data and seismic attribute analysis reveal that late Ordovician-early Devonian Hunton Group strata are more widespread (i.e., not removed by mid-Devonian erosion) in the central and southern portions of the Arkoma Basin in eastern Oklahoma than previously thought. This study demonstrates the value of applying seismic attribute analysis to problems of quantifying and mapping stratigraphic features caused by erosions and/or karstification. Well and seismic isochron data in the Red Oak petroleum field for the Viola-Woodford interval (the units that lie stratigraphically beneath and above, respectively, the Huton Group) show isolated ~40-m thick lenses of Hunton rocks, …
Dendrochronological Analysis Of White Oak Tree (Quercus Alba) Cores From The Mizer Log Cabin, Coshocton County, Ohio
Historic Structures
Dating historical structures in Coshocton County, Ohio using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Belding, Elyssa; Wiles, Greg.
Dendrochronological Analysis Of The Strouse Barn, Holmes County, Ohio
Dendrochronological Analysis Of The Strouse Barn, Holmes County, Ohio
Historic Structures
Dating historical structures in Holmes County, Ohio using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Belding, Elyssa; Wiles, Greg
Laboratory Based Chemical And Isotopic Investigations On Biotic (Microbial) And Abiotic Reduction Of Iron And Oxidation Of Organic Compounds, Tsigabu Asmelash Gebrehiwet
Laboratory Based Chemical And Isotopic Investigations On Biotic (Microbial) And Abiotic Reduction Of Iron And Oxidation Of Organic Compounds, Tsigabu Asmelash Gebrehiwet
Dissertations
Studies using chemical and isotopic techniques have been conducted to investigate experimental microbial (biotic) iron reduction and abiotic redox processes. In the microbially mediated study Fe(III) reduction and lactate oxidation at circum-neutral pH and anaerobic conditions were used to characterize the metabolic pathways followed by dissimilatory Fe+3 -reducing bacterium Shewanella putrefaciens strain 200R. Iron (II), Iron (III), dissolved inorganic carbon (DIC) and carbon isotope ratios were measured under bicarbonate and phosphate buffered conditions. Carbon isotope disproportionation among organic carbon substrate (lactate), biomass and respired carbon dioxide at the lag to stationary phase of the microbial growth curve showed …