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Articles 901 - 930 of 1152
Full-Text Articles in Earth Sciences
Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson
Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson
School of Geosciences Faculty and Staff Publications
Terrestrial radar interferometry (TRI) is a new technique for studying ice motion and volume change of glaciers. TRI is especially useful for temporally and spatially dense measurements of highly dynamic glacial termini. We conducted a TRI survey of Breiðamerkurjökull, a marine-terminating glacier in Iceland, imaging its terminus near the end of the melt season in 2011, 2012 and 2013. The ice velocities were as high as 5 m d−1, with the fastest velocities near the calving front. Retreat of the glacier over the 3 year observation period was accompanied by strong embayment formation. Iceberg tracking with the radar shows high …
Did Shell-Crushing Crabs Trigger An Escalatory Arms Race In The Aftermath Of A Late Neogene Regional Mass Extinction Event? An Experimental Test, Lisa B. Whitenack, Gregory S. Herbert
Did Shell-Crushing Crabs Trigger An Escalatory Arms Race In The Aftermath Of A Late Neogene Regional Mass Extinction Event? An Experimental Test, Lisa B. Whitenack, Gregory S. Herbert
School of Geosciences Faculty and Staff Publications
A regional mass extinction event in the late Neogene western Atlantic is widely thought to have generated evolutionary opportunities for survivors, including enemy-related adaptation (escalation). The Strombus alatus species complex is one potential example of this phenomenon. Strombid gastropods are abundant in the Plio-Pleistocene fossil record and Recent in subtropical Florida, and the percentage of these shells bearing a row of short spines on the last whorl increased from nearly zero to almost 100% over this time. As shell ornamentation is one of the most frequently cited defenses against both peeling and crushing predators, we exposed live spined and spineless …
Mapping Robinia Pseudoacacia Forest Health Conditions By Using Combined Spectral, Spatial, And Textural Information Extracted From Ikonos Imagery And Random Forest Classifier, Hong Wang, Yu Zhao, Ruiliang Pu
Mapping Robinia Pseudoacacia Forest Health Conditions By Using Combined Spectral, Spatial, And Textural Information Extracted From Ikonos Imagery And Random Forest Classifier, Hong Wang, Yu Zhao, Ruiliang Pu
School of Geosciences Faculty and Staff Publications
The textural and spatial information extracted from very high resolution (VHR) remote sensing imagery provides complementary information for applications in which the spectral information is not sufficient for identification of spectrally similar landscape features. In this study grey-level co-occurrence matrix (GLCM) textures and a local statistical analysis Getis statistic (Gi), computed from IKONOS multispectral (MS) imagery acquired from the Yellow River Delta in China, along with a random forest (RF) classifier, were used to discriminate Robina pseudoacacia tree health levels. Specifically, eight GLCM texture features (mean, variance, homogeneity, dissimilarity, contrast, entropy, angular second moment, and correlation) were first calculated from …
Trace Element Behavior During Coal Combustion: Insights From Cadmium And Zinc Isotope Analysis, Fotios Fouskas
Trace Element Behavior During Coal Combustion: Insights From Cadmium And Zinc Isotope Analysis, Fotios Fouskas
Open Access Theses & Dissertations
Due to its low cost and abundance, coal has been pervasively used in recent decades to meet large energy demands worldwide. Coal combustion provides the dominant electrical source in the U.S and produces over 100 million tons of coal combustion products (CCPs) per year domestically. The disposal/beneficial use of CCPs has the potential to release toxic trace elements, including cadmium (Cd) and zinc (Zn), into the environment. High temperature combustion of coal changes both physical states and chemical properties of Cd and Zn compounds in CCPs. Related processes such as evaporation and condensation, can lead to mass-dependent fractionation of Cd …
Fine-Scale Plant Species Identification In A Poor Fen And Integration Of Techniques And Instrumentation In A Classroom Setting, Dylan Schiff
Fine-Scale Plant Species Identification In A Poor Fen And Integration Of Techniques And Instrumentation In A Classroom Setting, Dylan Schiff
Honors Theses and Capstones
Refining carbon flux measurements in the carbon cycle is an ongoing challenge. This study attempted to identify plant species in Sallie’s Fen, a nutrient-poor fen in Barrington, New Hampshire, at a fine scale in order to better model and understand carbon exchange between plants and the atmosphere in this type of ecosystem. A protocol for estimating percent cover of species in plots via ground measurements was developed. The next stage of this project was to compare these measurements with measurements derived from spectral images using ImageJ computer software. Statistical tests of the ground measurement data revealed that patterns of seasonal …
On The Uncertainty Of Sea-Ice Isostasy, Cathleen Geiger, Peter Wadhams, Hans-Reinhard Müller, Jacqueline Richter-Menge
On The Uncertainty Of Sea-Ice Isostasy, Cathleen Geiger, Peter Wadhams, Hans-Reinhard Müller, Jacqueline Richter-Menge
Dartmouth Scholarship
During late winter 2007, coincident measurements of sea ice were collected using various sensors at an ice camp in the Beaufort Sea, Canadian Arctic. Analysis of the archived data provides new insight into sea-ice isostasy and its related R-factor through case studies at three scales using different combinations of snow and ice thickness components. At the smallest scale (<1 m; point scale), isostasy is not expected, so we calculate a residual and define this as �� (‘zjey’) to describe vertical displacement due to deformation. From 1 to 10 m length scales, we explore traditional isostasy and identify a specific sequence of thickness calculations which minimize freeboard and elevation uncertainty. An effective solution exists when the R-factor is allowed to vary: ranging from 2 to 12, with mean of 5.17, mode of 5.88 and skewed distribution. At regional scales, underwater, airborne and spaceborne platforms are always missing thickness variables from either above or below sea level. For such situations, realistic agreement is found by applying small-scale skewed ranges for the R-factor. These findings encourage a broader isostasy solution as a function of potential energy and length scale. Overall, results add insight to data collection strategies and metadata characteristics of different thickness products.
Maritime Exposure And Economic Prosperity: Why Location Matters, Jesse M. Lane
Maritime Exposure And Economic Prosperity: Why Location Matters, Jesse M. Lane
Theses
No abstract provided.
Microtremor Recordings In Northern Mississippi: Evaluating Site Effect And Correlating With Wave Climate, Zhen Guo
Electronic Theses and Dissertations
Site effects is considered as one of the main reasons that cause enormous damages in earthquakes and it is mainly controlled by the local geological condition. The main research area, Northern Mississippi, is located in Mississippi Embayment (ME) where is mainly composed of unconsolidated sediments which can be as thick as 1400m along the Mississippi River floodplain, and is favorable to have significant site effects. Meanwhile Northern Mississippi is also located in the moderate to heavy potential damage area of the New Madrid Seismic Zone, which is in the northern section of ME. Therefore, it is very necessary to evaluate …
Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton
Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton
Electronic Theses and Dissertations
Long-term groundwater level and stream stage measurements at a USGS coupled groundwater stream-gaging station located on the Sunflower River in Sunflower, MS show an apparent stage-threshold for infiltration to the underlying alluvial aquifer. This site is located near the center of a large regional groundwater cone of depression in the Mississippi River Valley alluvial aquifer. The USGS well (termed well 3 in this study) was thought to be completed in the regional shallow aquifer, though often recording anomalously high water levels relative to other wells in the region. The purpose of this research was to identify the responsible mechanism for …
Spectroscopic Characterization Of Oceanic Dissolved Organic Matter Isolated By Reverse Osmosis Coupled With Electrodialysis, John R. Helms, Jingdong Mao, Hongmei Chen, E. Michael Perdue, Nelson W. Green, Patrick G. Hatcher, Kenneth Mopper, Aron Stubbins
Spectroscopic Characterization Of Oceanic Dissolved Organic Matter Isolated By Reverse Osmosis Coupled With Electrodialysis, John R. Helms, Jingdong Mao, Hongmei Chen, E. Michael Perdue, Nelson W. Green, Patrick G. Hatcher, Kenneth Mopper, Aron Stubbins
Chemistry & Biochemistry Faculty Publications
Oceanic dissolved organic matter (DOM) is one of the largest pools of reduced carbon on Earth, yet DOM remains poorly chemically characterized. Studies to determine the chemical nature of oceanic DOM have been impeded by the lack of efficient and non-fractioning methods to recover oceanic DOM. Here, a DOM fraction (~40 to 86% recovery) was isolated using reverse osmosis/electrodialysis (RO/ED) and analyzed by solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Samples were obtained from biogeochemically distinct environments: photobleached surface gyre, productive coastal upwelling zone, oxygen minimum, North Atlantic Deep Water, and North Pacific Deep Water. A ubiquitous ‘background’ refractory …
Use Of Esi-Fticr-Ms To Characterize Dissolved Organic Matter In Headwater Streams Draining Forest-Dominated And Pasture-Dominated Watersheds, Yuehan Lu, Xiaping Li, Rajaa Mesfioui, James E. Bauer, R. M. Chambers, Elizabeth A. Canuel, Patrick G. Hatcher
Use Of Esi-Fticr-Ms To Characterize Dissolved Organic Matter In Headwater Streams Draining Forest-Dominated And Pasture-Dominated Watersheds, Yuehan Lu, Xiaping Li, Rajaa Mesfioui, James E. Bauer, R. M. Chambers, Elizabeth A. Canuel, Patrick G. Hatcher
Chemistry & Biochemistry Faculty Publications
Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proven to be a powerful technique revealing complexity and diversity of natural DOM molecules, but its application to DOM analysis in grazing-impacted agricultural systems remains scarce. In the present study, we presented a case study of using ESI-FTICR-MS in analyzing DOM from four headwater streams draining forest-or pasture-dominated watersheds in Virginia, USA. In all samples, most formulas were CHO compounds (71.8-87.9%), with other molecular series (CHOS, CHON, CHONS, and CHOP (N, S)) accounting for only minor fractions. All samples were dominated by molecules falling in the lignin-like region (H/C …
Spatial Incidence Of Adult Obesity In The State Of Alabama, Mary G. Odhiambo
Spatial Incidence Of Adult Obesity In The State Of Alabama, Mary G. Odhiambo
Theses
No abstract provided.
Volcanoes Of The Hawaiian Islands And The Pacific Northwest, Bayaan Manasra
Volcanoes Of The Hawaiian Islands And The Pacific Northwest, Bayaan Manasra
A with Honors Projects
Destructive, deadly, and able to uproot and ruin lives, yet awe inspiring and a supportive platform for the growth of a wide range of organic entities. Volcanoes are a powerful force of nature that intrigue many but at the same time are widely misunderstood. These impressive structures can be formed in a variety of different ways and there are even factors that affect the explosive properties of magma. Why do the Hawaiian Islands seem to be ever-expanding? Is the volcanic arc of the Pacific Northwest region still active? What makes the lava of some volcanoes flow out like a burning …
Assessing The Relative Mobility Of Submarine Landslides From Deposit Morphology And Physical Properties: An Example From Kumano Basin, Nankai Trough, Offshore Japan, Zachary T. Moore
Theses and Dissertations--Earth and Environmental Sciences
A prominent landslide deposit in the Slope Basin seaward of the Megasplay Fault in the Nankai Trough was emplaced by a high-mobility landslide based on analysis of physical properties and seismic geomorphology. Slide acceleration is a critical variable that determines amplitude of slide-generated tsunami but is many times a variable with large uncertainty. In recent controlled laboratory experiments, the ratio of the shear stress to yield strength (defined as the Flow Factor) controls a wide spectrum of mass movement styles from slow, retrogressive failure to rapid, liquefied flows. Here, we apply this laboratory Flow Factor approach to a natural landslide …
Dynamic Surface Water-Groundwater Exchange In Tidal Freshwater Zones: Insights From The Christina River Basin (Delaware, Usa), Cole T. Musial
Dynamic Surface Water-Groundwater Exchange In Tidal Freshwater Zones: Insights From The Christina River Basin (Delaware, Usa), Cole T. Musial
Theses and Dissertations--Earth and Environmental Sciences
In coastal rivers, tides can propagate for tens to hundreds of kilometers inland beyond the saltwater line. Yet the influence of tides on river-aquifer connectivity and solute transport in tidal freshwater zones (TFZs) is largely unknown. We estimate that along the TFZ of White Clay Creek (Delaware, USA), more than 17% of river water exchanges through hyporheic and riparian storage zones due to tidal pumping alone. Additional hyporheic processes such as flow through bedforms likely contribute even more exchange. The turnover length associated with the tidal pumping process is 39 km, similar to turnover lengths for all hyporheic exchange processes …
Finding Mars Paleopoles From Magnetization Edge Effects To Determine The History Of Mars’ Core Dynamo, Melissa Lynn Ditty
Finding Mars Paleopoles From Magnetization Edge Effects To Determine The History Of Mars’ Core Dynamo, Melissa Lynn Ditty
Theses and Dissertations--Earth and Environmental Sciences
This is a new method of determining magnetization strength, direction, and paleopole location from magnetic anomalies across edges of the equatorial band of magnetic sources on Mars. Different assumed locations of paleopoles result in different inducing field directions in the vicinity of an edge. Thus, with different paleopoles, the resulting magnetic fields from the edges of magnetic sources are different, and correlate differently with the observed fields. Best correlating observed and computed magnetic edge effect fields yield the potential paleopoles. The total gradient (TG) of the z-component magnetic field was used to identify the edges of magnetization boundaries. Three edge …
The Environmental Effects Of Coal Fires, Trent Garrison
The Environmental Effects Of Coal Fires, Trent Garrison
Theses and Dissertations--Earth and Environmental Sciences
There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in …
Bedrock Geologic Mapping And Structural Analysis Of The Western Half Of The Petersham Quadrangle, Central Massachusetts: Further Tests Of The Model For Middle To Late Paleozoic Ductile Transpression, Vertical Extrusion, And Lateral Escape In The Northern Appalachians, Lucas P. Rohrer
Theses and Dissertations--Earth and Environmental Sciences
Bedrock mapping, structural analysis, and geochronology reveal the distribution of lithologies and timing of metamorphism and deformation in the western half of the Petersham 7.5’ quadrangle, western Massachusetts. Underlying lithologies are: (from west to east) the Ordovician Monson granitic orthogneiss, Silurian Rangeley migmatitic paragneiss, and Late Devonian (357 Ma) Hardwick tonalitic orthogneiss. Their tightly folded contacts strike north to south. The 361 Ma, unfoliated, strike-parallel Nichewaug quartz-diorite (10-100 m wide) intrusion spans the map area within the Rangeley. Evidence for vertical and lateral extrusion/escape of the Monson orthogneiss, as observed in the Palmer MA area, is absent. Instead, petrofabrics (foliations …
Fluvial Responses To Growth Faulting In The West Pearl River, Louisiana, Stephen A. Prosser
Fluvial Responses To Growth Faulting In The West Pearl River, Louisiana, Stephen A. Prosser
Theses and Dissertations--Earth and Environmental Sciences
The Pearl River Delta (PRD) in southeastern Louisiana is an actively deforming deltaic complex displaying surface and near-surface evidence of growth faulting. Active growth faults in these environments are rarely identified at the surface, in part because the downthrown blocks often experience increased rates of sediment deposition leading to an obscured and low-relief, or entirely absent, surface expression. Faulting can be expressed in fluvial systems as changes in channel gradient, which often result in coincident changes in channel sinuosity, migration rates, planform deflections, and/or ponding features within the deformed zone. The study area is focused on a meander bend of …
Katian Gssp And Carbonates Of The Simpson And Arbuckle Groups In Oklahoma, Jesse R. Carlucci, Daniel Goldman, Carlton E. Brett, Stephen R. Westrop, Stephen A. Leslie
Katian Gssp And Carbonates Of The Simpson And Arbuckle Groups In Oklahoma, Jesse R. Carlucci, Daniel Goldman, Carlton E. Brett, Stephen R. Westrop, Stephen A. Leslie
Department of Earth, Environment and Sustainability Faculty Publications
This guidebook was written for the 2015 International Symposium on the Ordovician System (ISOS) as a synopsis of the recent work (e.g., Goldman et al. 2007; Carlucci et al. 2014, forthcoming work for the ISOS meeting) on Ordovician-Silurian rocks of south-central and south-eastern Oklahoma. This new research and past studies (e.g., Harris 1957; Longman 1976; Longman 1982a, b; Fay et al. 1982a; Fay et al. 1982b) underscore the scientific importance of this region. The global stratotype section and point for the Katian Stage of the Upper Ordovician Series is examined on this trip. The first appearances of important graptolites, conodonts …
Geologic Map Of The Welcome Quadrangle And An Adjacent Part Of The Wells Quadrangle, Elko County, Nevada, Allen J. Mcgrew, Arthur W. Snoke
Geologic Map Of The Welcome Quadrangle And An Adjacent Part Of The Wells Quadrangle, Elko County, Nevada, Allen J. Mcgrew, Arthur W. Snoke
Department of Earth, Environment and Sustainability Faculty Publications
Located in central Elko County, the Welcome and adjacent part of the Wells quadrangles expose a remarkable array of critical relationships for understanding the geologic history of the State of Nevada and the interior of the southwestern U.S. Cordillera. Covering the northern end of the East Humboldt Range and adjacent Clover Valley and Clover Hill, this map includes the northern terminus of the Ruby Mountains-East Humboldt Range metamorphic core complex. The oldest rocks in the State of Nevada (the gneiss complex of Angel Lake), and Nevada’s only exposures of Archean rock, form the core of a multikilometer scale, southward-closing recumbent …
Stream Bank Erosion Trends And Sediment Contributions In A Southwestern Missouri River, Ezekiel Allen Kuehn
Stream Bank Erosion Trends And Sediment Contributions In A Southwestern Missouri River, Ezekiel Allen Kuehn
Graduate Theses/Dissertations
Bank erosion can be a significant source of in-stream sediment that negatively affects water quality and aquatic habitat. However, assessments of the role that eroding banks play in suspended and bed sediment supply are rarely available to managers. The purpose of this study was to quantify bank erosion rates for a 7 km conservation easement the James River in southwest Missouri to evaluate the annual contributions of bank sediment to the channel. The objectives were to: (1) monitor an eroding 260 m bank to better understand short-term, reach scale bank erosion rates; (2) determine historical rates of bank erosion for …
Petrology And Geochemistry Of Mafic Dykes From The Muslim Bagh Ophiolite (Pakistan): Implications For Petrogenesis And Emplacement, Mohammad Ishaq Kakar, Khalid Mahmood, Mohammad Arif, Mehrab Khan, Andrew C. Kerr, Mohibullah Mohibullah, Aimal Khan Kasi
Petrology And Geochemistry Of Mafic Dykes From The Muslim Bagh Ophiolite (Pakistan): Implications For Petrogenesis And Emplacement, Mohammad Ishaq Kakar, Khalid Mahmood, Mohammad Arif, Mehrab Khan, Andrew C. Kerr, Mohibullah Mohibullah, Aimal Khan Kasi
Turkish Journal of Earth Sciences
Two different types of mafic dykes are found in the Muslim Bagh Ophiolite: 1) a sheeted dyke complex and 2) a mafic dyke swarm. Relative to the host plutonic section, the sheeted dykes are poorly developed, implying that they formed in an oceanic setting with a low and intermittent supply of magma, probably because of cyclic accumulation of crystals at the base of the magma chamber. Both the sheeted dykes and the dyke swarms have been metamorphosed to greenschist/amphibolite facies conditions. With the exception of the upper level gabbros and sheeted dykes, the dyke swarms crosscut almost the whole ophiolite …
New La-Icp-Ms U-Pb Zircon Dating For Strandja Granitoids (Se Bulgaria): Evidence For Two-Stage Late Variscan Magmatism In The Internal Balkanides, Philip Machev, Valentin Ganev, Laslo Klain
New La-Icp-Ms U-Pb Zircon Dating For Strandja Granitoids (Se Bulgaria): Evidence For Two-Stage Late Variscan Magmatism In The Internal Balkanides, Philip Machev, Valentin Ganev, Laslo Klain
Turkish Journal of Earth Sciences
The Strandja Massif (Sakar-Strandja Zone) forms an important link between the Balkan Zone (external Balkanides) of Bulgaria, which is commonly correlated with the Variscan orogen in Central Europe, and the Western Pontides of Turkey. The Bulgarian part of the massif is composed of a metamorphic basement (various granite gneisses, paragneisses, and schists) traditionally interpreted as having Precambrian age, Triassic-Jurassic metasedimentary cover, and Upper Cretaceous volcanosedimentary sequences. The basement is intruded by large granitic plutons of Variscan age that are widespread mostly across Turkish territory. New LA-ICP-MS data support the suggestion of Variscan granitoid magmatism in the studied area but do …
Thuringian Affinity Of The Silurian?Lower Devonian Succession From The Eastern Taurus, Turkey, Valeri Sachanski, Hüseyi̇n Kozlu, Mehmet Cemal Göncüoğlu
Thuringian Affinity Of The Silurian?Lower Devonian Succession From The Eastern Taurus, Turkey, Valeri Sachanski, Hüseyi̇n Kozlu, Mehmet Cemal Göncüoğlu
Turkish Journal of Earth Sciences
The Silurian-Lower Devonian succession in the Değirmentaş-Halevikdere section (E Taurides) shows considerable lithostratigraphic similarities to the three-partite subdivision, initially documented in the same stratigraphic interval in Saxo-Thuringia and later in other peri-Gondwanan terrains. The Llandovery-Wenlockian part of the studied section (ca. 40 m) is characterized by black graptolitic shales. The Llandoverian part is dominated by radiolarian ribbon cherts (ca. 20 m). The Rhuddanian Akidograptus ascensus, Parakidograptus acuminatus, and Cystograptus vesiculosus biozones have been recognized in its lower part, while in the upper part of the succession, the lowermost Telychian Rastrites linnaei Biozone has been documented. The Telychian Spirograptus turriculatus and …
The 2009 And 2011 Hazard Events At San Vicente Volcano, El Salvador: Vulnerability, Resettlement, And Disaster Risk Reduction, Luke Bowman
Dissertations, Master's Theses and Master's Reports
Scientists from a variety of disciplines have made major advancements in the geophysical and social aspects of hazard science. Despite these advancements, economic losses and the number of people affected by disasters continue to rise. The field of disaster risk reduction (DRR) attempts to counter this rising trend of disaster losses by integrating a variety of disciplines to holistically solve complex problems related to risk and vulnerability. Frequent disasters in El Salvador provide insight into the evolution of DRR and its application during and after two hydrometeorological disasters in the department of San Vicente in 2009 and 2011. This dissertation …
Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi
Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi
Dissertations, Master's Theses and Master's Reports
Pacaya is one of the most active volcano in the world and it is only ≈30Km South of Guatemala City, the capital of Guatemala, that has a population of about 2 million of people and a surrounding metropolitan area where ≈4.5 million of people live. So mitigate the volcanic hazard improving the knowledge and the understanding of Pacaya is fundamental to decrease the risk factor at which the surrounding population is exposed. This study aims to furnish a new large database, the analysis, the comparison and the interpretations of data that come from different techniques of sampling, about the volcanic …
Deterministic And Stochastic Inversion Techniques Used To Predict Porosity: A Case Study From F3-Block, Hao Wu
Dissertations, Master's Theses and Master's Reports
Within large-scale sigmoidal bedding of the F3-block in the shallow zone there appear to be some indicators of hydrocarbon deposits. In order to characterize target zone in the sigmoidal bedding, I combine the analysis of inverted results of post-stack seismic data with rock-physics relationships developed from well log data to predict the porosity, which ranges from 20% to 33%, for different system tracts in this area. The methods used in this study include conventional deterministic inversion and novel stochastic inversion. Through a rock physics analysis of the density, velocity and gamma-ray logs in two wells, I constructed relationships between the …
Tracing Sediment In The Subsurface Using Beryllium-7: Green River Basin, Ky, Caroline Adams Broderick
Tracing Sediment In The Subsurface Using Beryllium-7: Green River Basin, Ky, Caroline Adams Broderick
LSU Master's Theses
As water flows through areas of limestone, karst inevitably develops, creating sinking streams and sinkholes that transport alumino-silicate particles from the surface into the subsurface. Sediment budget studies on short term scales through karst are rare. Thus, a feasibility study using beryllium-7 (7Be), which attaches to soil particles and can be used as a short-term (2-3 month) tracer of the movement of fine-grained sediment in karst was investigated. Sediment samples were collected from a karstic catchment within Green River basin, Kentucky, both on the surface and in the subsurface along a cave stream. Samples were collected prior to and immediately …
Chlorine Enrichment Of Hydrous Minerals In Archean Granulite Facies Ironstone From The Beartooth Mountains, Montana, Usa: Implications For High-Grade Metamorphic Fluids, Nicholas Michael Daigle
Chlorine Enrichment Of Hydrous Minerals In Archean Granulite Facies Ironstone From The Beartooth Mountains, Montana, Usa: Implications For High-Grade Metamorphic Fluids, Nicholas Michael Daigle
LSU Master's Theses
The amount of chlorine present in hydrous minerals influences mineral stability and may serve as a monitor of the evolving fluid phase during progressive metamorphism. Chlorine contents of amphibole and biotite vary as a function of temperature, pressure, crystallochemical factors, and fluid composition. The sensitivity of these minerals to serve as a monitor of Cl in aqueous fluids is particularly effective in Fe-rich amphibole and biotite such as those found in ironstones. Ironstones from the eastern Beartooth Mountains, Montana are typified by dominantly anhydrous mineral assemblages of quartz + magnetite + orthopyroxene + garnet ± clinopyroxene and have equilibrated during …