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2012

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Articles 811 - 840 of 988

Full-Text Articles in Earth Sciences

Assessment Of Climate Change Effect On Water Harvesting Structures In Rainfed Regions: Geospatial Data Mining Approach, Sreedhar Nallan, Leisa Armstrong Jan 2012

Assessment Of Climate Change Effect On Water Harvesting Structures In Rainfed Regions: Geospatial Data Mining Approach, Sreedhar Nallan, Leisa Armstrong

Research outputs 2012

Advances in the Information and Technologies (ICT) may assist researchers in the assessment of watershed development programmes by developing better visualization understanding of their impacts. GIS based research studies utilizing remote sensing images can facilitate in identifying the potential zones for watershed development and enable improved ground water resources. Effective watershed management is dependent on a number of factors such as demography, climate, soil, land use and topography and these are affected by changing climatic conditions. For example, changes in rainfall intensity and volume in rain fed areas can influence the effectiveness of the placement of watershed structures. Existing methods …


Closure Planning In A Developing Country - A Case Study From The Phu Kham Mine, Laos, Southeast Asia, Amy Mauric, C. D. Mccullough, Charlie Wilson-Clark, Andrew Witcomb, Jeff Millgate Jan 2012

Closure Planning In A Developing Country - A Case Study From The Phu Kham Mine, Laos, Southeast Asia, Amy Mauric, C. D. Mccullough, Charlie Wilson-Clark, Andrew Witcomb, Jeff Millgate

Research outputs 2012

Mining in developing regions face significant challenges for effective closure planning. A maturing mine closure regulatory environment and limited capacity within government to regulate mine closure issues can present considerable risk from an operation to the regional community and environment. Alternatively, if the operation adopts leading practice international standards in recognition of their corporate responsibilities and social license‐to‐mine in developing countries, there may be significant opportunities for enhanced social and environmental outcomes for host country and mining company. Using a case study from the Phu Kham Mine, Lao People’s Democratic Republic (Laos), we discuss some of the key challenges to …


Holocene Arroyo Cut And Fills Cycles, South-Central Washington, Matthew Ian Durkee Jan 2012

Holocene Arroyo Cut And Fills Cycles, South-Central Washington, Matthew Ian Durkee

All Master's Theses

Ephemeral streams have cut deeply incised arroyos into alluvial and eolian sediments in many of the watersheds within the Yakima Training Center (YTC) military reservation, south-central Washington. The most recent channel incision episode along Selah Creek is primarily attributed to multiple failures of an irrigation reservoir dam during the winters of 1909 and 1910. The modern arroyo exposed evidence of at least one previous episode of arroyo incision to a depth of ~4 m that occurred just prior to 1530- 1340 cal yr BP. Filling of this paleo-arroyo with fine to coarse grained sand ceased between 650-103 cal yr BP. …


Applying Gis Metrics To Determine Degree Of Glacial Modification In Mountainous Landscapes, Carl Delbert Swanson Ii Jan 2012

Applying Gis Metrics To Determine Degree Of Glacial Modification In Mountainous Landscapes, Carl Delbert Swanson Ii

All Master's Theses

The ability to quantitatively assess the degree of glaciation in mountainous areas can be a powerful tool in unraveling the evolution of landscapes, and provide key insights in regions where field research is difficult. Here we determine, test, and apply metrics that assess the relative degree of past glacial modification in mountainous landscapes. Results show that slope results can be used to quantitatively assess the degree to which an area is modified by glaciation. In particular, analysis of basins using slope frequency distribution curves and slope vs. elevation plots capture steeper slopes, flatter valley bottoms, cirques, and arêtes of glaciated …


Documenting The Origin Of Compositional Diversity Of Subduction Zone Magmatism, Alicudi, Aeolian Arc (Southern Tyrrhenian Sea, Italy) Using In Situ Plagioclase Data, Rachel Hunt Jan 2012

Documenting The Origin Of Compositional Diversity Of Subduction Zone Magmatism, Alicudi, Aeolian Arc (Southern Tyrrhenian Sea, Italy) Using In Situ Plagioclase Data, Rachel Hunt

All Master's Theses

Processes that generate magma compositional diversity are important to document because composition affects degree of explosivity, which impacts hazard mitigation. Magnesium to silicon rich magmas are produced by processes such as magma recharge, assimilation, and fractional crystallization (RAFC) that occur in subvolcanic magma chamber(s). This study evaluates how magma chamber processes contribute to compositional diversity at Alicudi Volcano, Italy. Analytical and petrographic data from ten samples that span the subaerial history include whole rock major and trace elements and strontium/neodymium isotopes, and plagioclase textural types, major and trace elements, and strontium isotopes; numerical modeling was also conducted. Integration of these …


Documenting Magma Evolution Of The Fossa Delle Felci (Salina Island, South Tyrrhenian Sea) By Integrating In Situ Plagioclase Data With Quantitative Modeling, Aaron Mayfield Jan 2012

Documenting Magma Evolution Of The Fossa Delle Felci (Salina Island, South Tyrrhenian Sea) By Integrating In Situ Plagioclase Data With Quantitative Modeling, Aaron Mayfield

All Master's Theses

Compositional diversity occurs via processes dominated by recharge, assimilation and fractional crystallization (RAFC), quantification of which can provide insights into eruption catalysts, and therefore assist in hazard mitigation. This study evaluates the relative roles of RAFC processes in Fossa delle Felci (Salina Island, Italy) magmas, which span the basalt to dacite range (52-65 wt% SiO2). Integration of petrographic, whole rock, and in situ plagioclase data with quantitative magma chamber models suggests differentiation dominated by fractional crystallization and magma recharge/mixing in reservoirs located at different crustal levels. At ~12 km depth, magma evolved through crystallization of a pyroxene dominated assemblage; plagioclase …


Petrogenetic Relationship Of The Postcaldera Eruptions Of Mount Mazama, Crater Lake, Oregon; Evolution Of A Sub-Volcanic Magma Chamber Following A Large Silicic Eruption, Michelle Leanna Tebbe Jan 2012

Petrogenetic Relationship Of The Postcaldera Eruptions Of Mount Mazama, Crater Lake, Oregon; Evolution Of A Sub-Volcanic Magma Chamber Following A Large Silicic Eruption, Michelle Leanna Tebbe

All Master's Theses

Mount Mazama is the volcanic edifice that cataclysmically erupted ~503 km of relatively homogeneous rhyodacite lava ~ 7,700 years ago, forming the caldera known as Crater Lake. Within a few hundred years, andesitic eruptions built three distinct volcanic edifices on the floor of Crater Lake; ~ 3000 years later, rhyodacite eruptions formed a dome (Bacon et al., 2002). How magmatic systems evolve following a shallow, relatively large silicic eruption is the focus of this study. In situ geochemical analysis coupled with high-resolution textural images of plagioclase crystals in the four postcaldera volcanic edifices were used to identify distinct crystal populations …


A New Phase Speciation Leaching Procedure For The Determination Of Metals In Oxic And Anoxic Sediments, Brandon R. Gipson Jan 2012

A New Phase Speciation Leaching Procedure For The Determination Of Metals In Oxic And Anoxic Sediments, Brandon R. Gipson

OES Theses and Dissertations

Toxic trace elements such as cadmium, lead, chromium, and arsenic released by human activities can accumulate in marine and estuarine sediments, where these metals are often sequestered until local environmental changes (e.g., redox, salinity, and/or pH) allow these elements to be reintroduced into the food web. In order to assess the extent of toxic trace element contamination in sediment, numerous leaching schemes have been developed that separate sediment-bound trace metals into operationally defined geochemical phases. These "phase speciation" leaching schemes are typically designed with the purpose of being used on either oxic or anoxic sediments. However, natural sediments often contain …


Documenting Magnatic Processes At Filicudi Island, Aeolian Arc, Italy: Integrating Quantitative Modeling And Plagioclase Textural And In Situ Compositional Data, Michelle Harris Jan 2012

Documenting Magnatic Processes At Filicudi Island, Aeolian Arc, Italy: Integrating Quantitative Modeling And Plagioclase Textural And In Situ Compositional Data, Michelle Harris

All Master's Theses

Documenting the physiochemical processes that influence magma composition is critical for forecasting eruption styles and managing volcanic hazards. Compositional diversity of magmas develops through recharge, assimilation, and fractional crystallization (RAFC) within subvolcanic magma reservoirs. Integration of MELTS modeling, whole rock, plagioclase textural and in situ elemental and isotopic data from Filicudi Island, Italy allow documentation of the roles and relative chronology that RAFC played in the magmatic evolution and elucidates aspects of the magma plumbing system structure.

Results indicate a polybaric magma plumbing system with deeper (3.5-4 kilobars) and shallower (0.5-1.2 kilobars) storage regions. Within the deeper system, FC acted …


The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson Jan 2012

The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson

LSU Master's Theses

Defining the linkages between microbial metabolic activity and environmental geochemistry can be used to understand how carbonate dissolution in sulfidic karst systems proceeds. In Lower Kane Cave, Wyoming, sulfidic springs support taxonomically distinct microbial communities that are also associated with putative sulfur metabolisms (e.g., oxidation of reduced sulfur compounds, sulfate reduction, and sulfur disproportionation) that influence carbonate dissolution. The distribution of diverse microbial groups in other terrestrial subsurface environments is not well understood, making Lower Kane Cave ideal for study. Molecular genetics techniques were used to uncover diversity of 16S rRNA genes and bacterial soxB and aprA functional genes. Aqueous …


Spatial Variation Analysis Of Salinity To Determine Fluid Flow Pathways And Reservoir Compartmentalization In A Deepwater Gulf Of Mexico Field, William Jacob Daugherty Jan 2012

Spatial Variation Analysis Of Salinity To Determine Fluid Flow Pathways And Reservoir Compartmentalization In A Deepwater Gulf Of Mexico Field, William Jacob Daugherty

LSU Master's Theses

Variations in salinity have been documented in previous studies onshore Louisiana in the Wilcox group (Funayama and Hanor 1995) as well as offshore Louisiana on the continental shelf (Bruno and Hanor 2003 and Steen et al. 2011). These studies were conducted using various methods to estimate pore water salinity and make inferences about possible fluid flow pathways and compartmentalization of reservoirs in order to better understand the complex hydrogeology of the Gulf of Mexico. Similar variations in salinity were documented in this study located in a deepwater salt withdrawal minibasin located on the upper slope of the Gulf of Mexico. …


A High-Resolution Palynological Analysis Of The St. Stephens Quarry, Alabama: Locating The Eocene-Oligocene Boundary And Characterizing The Environmental Changes Across The Margin, Kevin Jensen Jan 2012

A High-Resolution Palynological Analysis Of The St. Stephens Quarry, Alabama: Locating The Eocene-Oligocene Boundary And Characterizing The Environmental Changes Across The Margin, Kevin Jensen

LSU Master's Theses

The Eocene-Oligocene (E-O) transition is a key interval in geological history because it marks a major change in Earth’s climate and because these strata are also popular oil targets in the Gulf Coast. E-O sequences in Alabama are stratigraphically complex. The St. Stephens Quarry (SSQ) in Alabama is one of the few accessible quarries along the Gulf Coast where the E-O boundary is visible in outcrop. Despite the abundance of research projects conducted in the SSQ, many controversies still surround the E-O boundary placement and correlation to the Global Stratotype in the Massignano section in Italy that is based on …


U-Pb Geochronology Of Detrital Zircon In Quartzites Of The Sawtooth Metamorphic Complex, Sawtooth Range, Idaho, Usa, Philip Gerard Bergeron Jan 2012

U-Pb Geochronology Of Detrital Zircon In Quartzites Of The Sawtooth Metamorphic Complex, Sawtooth Range, Idaho, Usa, Philip Gerard Bergeron

LSU Master's Theses

In southwest Laurentia, the Paleoproterozoic Selway terrane has been proposed to extend as basement from the Wyoming Province to the Proterozoic rifted margin of Laurentia primarily based on limited exposures. The Sawtooth Metamorphic Complex (SMC), Idaho, a series of high-grade metasupracrustal rocks lies within the proposed region of the Selway terrane and may represent remnants of this terrane. Alternatively, it may represent another basement terrane of cratonic North America. To test the hypothesis that the SMC belongs to the Selway terrane, detrital zircon U/Pb ages of five quartzite samples were analyzed by LA-ICP-MS to establish age, possible provenance, and age …


Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson Jan 2012

Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson

LSU Master's Theses

Site 380 of the Deep Sea Drilling Program [DSDP] is located in the southwestern region of the Black Sea (42°05.94’, 29°36.82’E). The location of this site is important due to its proximity to the narrow Bosphorus strait, the only present-day connection between the Black Sea and the Aegean Sea. Drops in eustatic sea level during extensive Pleistocene glacial episodes disconnected the Black Sea from the Aegean Sea at the Bosphorus strait, creating a change from brackish to freshwater within the Black Sea during these intervals. Organic-walled phytoplankton (dinoflagellate cysts, acritarchs, and fresh-water algae) are investigated to better constrain these glacio-eustatic …


Glacial Deposits, Vol. 40, 2011-2012, Department Of Geography-Geology Jan 2012

Glacial Deposits, Vol. 40, 2011-2012, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Variations In Pore Water Salinities Above And Below Allochthonous Salt Sheets In The Deepwater Gulf Of Mexico: Implications For Mechanisms Of Solute Transport, Miles Alexander Mccammon Jan 2012

Variations In Pore Water Salinities Above And Below Allochthonous Salt Sheets In The Deepwater Gulf Of Mexico: Implications For Mechanisms Of Solute Transport, Miles Alexander Mccammon

LSU Master's Theses

Spatial variations in salinity of pore waters in marine sediments provide useful information on processes and rates of subseafloor fluid flow and solute transport, particularly if there are evaporites in the section. Pore water salinities were determined for 18 drill holes which penetrated allochthonous salt bodies in 12 widely-scattered protraction blocks on the Louisiana offshore continental shelf and slope. Salinities were calculated from Log ASCII Standard-Logging While Drilling (LAS-LWD) logs using the Revil et al. (1998) dual-conductivity technique. The sites represent a wide range of field settings. Water depths range from 30 to 1990 m, depths to the top of …


A Seismic Attribute Study To Assess Well Productivity In The Ninilchik Field, Cook Inlet Basin, Alaska, Andrew Sampson Jan 2012

A Seismic Attribute Study To Assess Well Productivity In The Ninilchik Field, Cook Inlet Basin, Alaska, Andrew Sampson

LSU Master's Theses

Coal bed methane which has formed in the Tertiary Kenai Group strata has been produced from the Ninilchik field of Cook Inlet, Alaska since 2001. Ninilchik field is located on the eastern margin of the central Cook Inlet along the Kenai Peninsula. Cook Inlet is a forearc basin and is characterized by northeast trending anticlines with upwards of 10,000 feet of Late Oligocene and younger, non-marine sediments. Highly variable well production within the Oligocene to Miocene Tyonek formation of the Kenai Group has been a source of uncertainty. A series of seismic attributes visualized in Schlumberger's Petrel® software were studied …


Implications Of Geothermal History On Microbial Gas Generation And Coalbed Methane Production In The Ninilchik Field, Cook Inlet Basin, Alaska, Eric M. Hart Jan 2012

Implications Of Geothermal History On Microbial Gas Generation And Coalbed Methane Production In The Ninilchik Field, Cook Inlet Basin, Alaska, Eric M. Hart

LSU Master's Theses

Coalbed methane (CBM) production operations atop the Ninilchik anticline of Cook Inlet, Alaska pose intriguing questions regarding the nature of biogenic gas generation in a thermally complex forearc basin setting. This thermal complexity stems, in part, from its up to 30,000 ft thick Tertiary section, comprised of braided stream alluvium and expansive, interbedded coal deposits. Rapid accumulation of cold, glacial strata is documented as being capable of regionally suppressing the elevated heat flux values expected within a forearc basin. In addition, beds with high organic content, such as the coal layers, act as natural insulators from basinal heat flux and …


Palynostratigraphy Of The Umir Formation, Middle Magdalena Valley Basin (Mmvb) Colombia, Carlos Enrique Santos Jan 2012

Palynostratigraphy Of The Umir Formation, Middle Magdalena Valley Basin (Mmvb) Colombia, Carlos Enrique Santos

LSU Master's Theses

The Late Cretaceous Umir Formation in Middle Magdalena Valley Basin (MMVB) was recently acknowledged as a new target. However, there is little known about the regional distribution of the Umir Formation since it is affected by structural complexity and a major regional unconformity. To improve biosteering of the Umir Formation and reduce exploratory risks, a detailed biostratigraphic analysis of the Umir Formation in the MMVB is presented. Eighty samples from four cores drilled in the Central Eastern MMVB were analyzed for palynological content. These cores represent 976.6 meters of the Middle to Upper Umir Formation. The sediment yielded a good …


Evaluation Of The Depositional Environment Of The Eagle Ford Formation Using Well Log, Seismic, And Core Data In The Hawkville Trough, Lasalle And Mcmullen Counties, South Texas, Zachary Paul Hendershott Jan 2012

Evaluation Of The Depositional Environment Of The Eagle Ford Formation Using Well Log, Seismic, And Core Data In The Hawkville Trough, Lasalle And Mcmullen Counties, South Texas, Zachary Paul Hendershott

LSU Master's Theses

The Upper Cretaceous Eagle Ford Formation of South Texas records a mixed siliciclastic/carbonate depositional environment across the Late Cretaceous Platform of the Gulf of Mexico. During the Late Cretaceous, LaSalle and McMullen Counties was part of the Hawkville Trough, a wedged shaped region between the Edwards and Sligo carbonate reefs. Well logs from 21 wells and seismic data were used to construct structure and isopach maps of the Eagle Ford Formation throughout the Hawkville Trough. Only the unconformable bottom (Buda-Eagle Ford) and top (Eagle Ford-Austin Chalk) boundaries plus the conformable boundary between the upper and lower Eagle Ford can be …


Sediment Flux & Fate For A Large-Scale Diversion: The 2011 Mississippi River Flood, The Bonnet Carré Spillway, And The Implications For Coastal Restoration In South Louisiana, Jeffrey Bryant Fabre Jan 2012

Sediment Flux & Fate For A Large-Scale Diversion: The 2011 Mississippi River Flood, The Bonnet Carré Spillway, And The Implications For Coastal Restoration In South Louisiana, Jeffrey Bryant Fabre

LSU Master's Theses

Dams and hardened levees built by European settlers in the last two centuries have degraded or stopped the cyclic sedimentation patterns that built the Mississippi River Delta Plain over the past 7,000-8,000 years. Man-made diversions of sediment-laden river water along the lower Mississippi, operated during high water periods, are being considered as a primary mechanism for combating the land loss induced by rising sea-level and these modern controls. To date, no study has documented the sediment-delivery potential of a large man-made river diversion during a single high water event. In the spring of 2011, historic flooding on the Mississippi River …


Natural And Anthropogenic Influences On The Morphodynamics Of Sandy And Mixed Sand And Gravel Beaches, Tiffany Roberts Jan 2012

Natural And Anthropogenic Influences On The Morphodynamics Of Sandy And Mixed Sand And Gravel Beaches, Tiffany Roberts

USF Tampa Graduate Theses and Dissertations

Beaches and coastal environments are dynamic, constantly shaped and reshaped by natural processes and anthropogenic modifications. The morphodynamics and influence of natural and anthropogenic factors of two different coasts at various temporal and spatial scales are discussed.

To quantify the performance of several beach nourishment projects at annual temporal and kilometer spatial scales on three adjacent microtidal low-wave energy barrier islands in west-central Florida, a total of 5,200 beach and nearshore-profiles spaced at 300 m were surveyed monthly to bi-monthly from 2006-2010. Beach nourishment performance is most significantly influenced by the interruption of longshore sediment transport by complex tidal-inlet processes. …


On The Spatial And Temporal Variability Of Upwelling In The Southern Caribbean Sea And Its Influence On The Ecology Of Phytoplankton And Of The Spanish Sardine (Sardinella Aurita), Digna Tibisay Rueda-Roa Jan 2012

On The Spatial And Temporal Variability Of Upwelling In The Southern Caribbean Sea And Its Influence On The Ecology Of Phytoplankton And Of The Spanish Sardine (Sardinella Aurita), Digna Tibisay Rueda-Roa

USF Tampa Graduate Theses and Dissertations

The Southern Caribbean Sea experiences a strong upwelling process along the coast from about 61°W to 75.5°W and 10-13°N. In this dissertation three aspects of this upwelling system are examined: (A) A mid-year secondary upwelling that was previously observed in the southeastern Caribbean Sea between June-July, when land based stations show a decrease in wind speed. The presence and effects of this upwelling along the whole southern Caribbean upwelling system were evaluated, as well as the relative forcing contribution of alongshore winds (Ekman Transport, ET) and wind-curl (Ekman Pumping, EP). (B) Stronger upwelling occurs in two particular regions, namely the …


Mapping And Assessing Urban Impervious Areas Using Multiple Endmember Spectral Mixture Analysis: A Case Study In The City Of Tampa, Florida, Fenqing Weng Jan 2012

Mapping And Assessing Urban Impervious Areas Using Multiple Endmember Spectral Mixture Analysis: A Case Study In The City Of Tampa, Florida, Fenqing Weng

USF Tampa Graduate Theses and Dissertations

The advance in remote sensing technology helps people more easily assess urban growth. In this study, the utility of multiple endmember spectral mixture analysis (MESMA) is examined in a sub-pixel analysis of Landsat Thematic Mapper (TM) imagery to map urban physical components in Tampa, FL. The three physical components of urban land cover (LC): impervious surface, vegetation and soil, were compared using the proposed MESMA with a traditional spectral mixture analysis (SMA). MESMA decomposes each pixel to address the heterogeneity of urban LC characteristic by allowing the number and types of endmembers to vary on a per pixel basis. This …


Variability In Hydrology And Ecosystem Properties And Their Role In Regulating Soil Organic Matter Stability In Wetlands Of West-Central Florida, Sharon Jean Feit Jan 2012

Variability In Hydrology And Ecosystem Properties And Their Role In Regulating Soil Organic Matter Stability In Wetlands Of West-Central Florida, Sharon Jean Feit

USF Tampa Graduate Theses and Dissertations

Soil organic matter (SOM) provides many ecosystem services that are necessary for continued ecosystem function. The accumulation of SOM in an ecosystem is a function of its persistence time which can range from days to thousands of years. Ecosystem properties including dominant vegetation type, soil texture, and soil moisture in various habitats can regulate the persistence time of SOM.

Wetlands, because of their associated ecosystem properties, promote SOM accumulation, but little has been done to determine the ecosystem properties that regulate its persistence over time. In west-central Florida, urbanization and increased water demands have suppressed water tables in isolated wetland …


Longitudinal Assessment Of Shifting Microbial Community Composition In Sandy Beaches Following The 2010 Deepwater Horizon Oil Spill And Remediation Efforts, Axita Ajaykumar Gupta Jan 2012

Longitudinal Assessment Of Shifting Microbial Community Composition In Sandy Beaches Following The 2010 Deepwater Horizon Oil Spill And Remediation Efforts, Axita Ajaykumar Gupta

LSU Master's Theses

Sandy beaches are geological zones parallel to the shoreline where high energy, open ocean unconsolidated sediments are deposited and reworked. Sandy beaches represent critical ecosystems that support a wide variety of underappreciated biodiversity. Prior to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, the diversity and function of microbial communities in supratidal beach sediments along the Gulf of Mexico coastlines were not well understood. It was unclear if possible community compositional changes would occur during and following exposure to oil, or what impact the remediation efforts, such as sand washing, would have to the microbial communities and …


A 2-D, Variable-Density Numerical Model Of Subsurface Fluid Flow Through The Edwards Aquifer, New Braunfels, Tx: Mechanisms Inhibiting Flow Across The Freshwater/Saline-Water Interface, Scott Ryan Tipple Jan 2012

A 2-D, Variable-Density Numerical Model Of Subsurface Fluid Flow Through The Edwards Aquifer, New Braunfels, Tx: Mechanisms Inhibiting Flow Across The Freshwater/Saline-Water Interface, Scott Ryan Tipple

LSU Master's Theses

The Edwards aquifer in south-central Texas, U.S., composed of faulted carbonate bedrock, contains freshwater and saline water. In aquifers that are used as a source of drinking water and that contain fresh and saline waters, saline-water intrusion can result in degradation of water quality. Yet, in the Edwards aquifer, limited saline-water intrusion has occurred. The questions addressed are “Why is the saline-water intrusion less than expected,” and “Is there a trigger that will result in saline-water intrusion into the freshwater reservoir?” Three hypotheses were tested. One: an extremely saline water density might prevent mixing across the interface. Two: faults could …


Stratigraphy And Sedimentology Of The Smackover Formation, Southwest Alabama, Andrew Wilbourn Jan 2012

Stratigraphy And Sedimentology Of The Smackover Formation, Southwest Alabama, Andrew Wilbourn

Electronic Theses and Dissertations

The Smackover Formation is a highly productive producer of hydrocarbons throughout the United States Gulf Coast region. More than four million barrels of oil and five billion cubic feet of gas have been produced from the Smackover Formation in the Barnett Field in southwest Alabama. Paleohighs formed during the Paleozoic and salt tectonic relief features control sediment distribution of the Smackover Formation in southwest Alabama. The Smackover in Barnett Field is entirely dolomitized, but the carbonate texture at the time of deposition is still visible in thin section. The Smackover carbonates in Barnett Field were deposited in the near-shore area …


Changing Land Use On Unproductive Soils, Andrew Blake, Mike Clarke, Angela Stuart-Street Jan 2012

Changing Land Use On Unproductive Soils, Andrew Blake, Mike Clarke, Angela Stuart-Street

Resource management technical reports

A three year study completed in 2010 examined farming systems in the north-eastern agricultural region and eastern wheatbelt of Western Australia which experienced a succession of variable seasons from 2000. This culminated in severe drought in 2006 and 2007. At that time, farmers experienced labour shortages and declining terms of trade triggered by cost inflation outpacing growth in commodity prices. As a result, farm business equity was eroded as farm debt escalated. This left many farm businesses in a highly vulnerable state. At the time of the study many farmers were facing an uncertain future.

These experiences, coupled with a …


Surface Layer Thickness And Velocity Determined Using The Multi Channel Analysis Of Surface Waves (Masw) Method Compared With Microtremor Resonance Analysis-Federal Road, Greene County, Ohio, Daniel R. Blake Jan 2012

Surface Layer Thickness And Velocity Determined Using The Multi Channel Analysis Of Surface Waves (Masw) Method Compared With Microtremor Resonance Analysis-Federal Road, Greene County, Ohio, Daniel R. Blake

Browse all Theses and Dissertations

Multi-Channel Analysis of Surface Waves (MASW) was performed on data collected at four locations previously occupied by 3-component broadband seismometers. The goal was to use MASW to define the velocity structure and depth to bedrock locally, and to examine how well the calculated surface layer resonance derived from this velocity structure compares with the surface layer resonance observed in the passive seismic data at that site. At the test site east of Xenia, Ohio, a clear change in lithology (glacial drift to limestone bedrock) on each of the 1-D MASW profiles is indicated by a substantial change in shear-wave velocity …