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Articles 241 - 270 of 423
Full-Text Articles in Earth Sciences
Conservation And Ecological Implications Of The Introgression Between Black Bass Subspecies, Rachel Tessier
Conservation And Ecological Implications Of The Introgression Between Black Bass Subspecies, Rachel Tessier
Honors Capstones
No abstract provided.
On The Amount Of Sediment Deposited In Floodplains From The Mississippi River: A Case Study In Cat Island National Wildlife Refuge, Louisiana, Matthew Smith
Honors Capstones
No abstract provided.
Oxygen Isotope Composition Of Phosphate Along Vertical Weathering Profiles That Developed On Igneous Rocks: Testing Modern Analogues For Identifying Terrestrial Life In Ancient Paleosols, Dustin Warn Boyd
LSU Master's Theses
Life on Earth began in its early oceans before moving on to land. Determining the exact timing of an established biosphere on land, however, has been elusive, due largely to the lack of either fossil or chemical evidence on land deposits. Here I test a hypothesis that the activity of land biota can be recorded in the oxygen isotope composition of phosphate in weathering profiles developed on igneous parent rocks. Igneous rock contains phosphate (PO43-), which is readily utilized for biological activities during soil development. The oxygen in PO43- does not readily exchange its oxygen …
Fault Kinematics Along The Coastal Plain Of South Louisiana: Implications For Tectono-Climatic-Induced Deformation Along A Passive Continental Margin, Ali A. Al Dhamen
Fault Kinematics Along The Coastal Plain Of South Louisiana: Implications For Tectono-Climatic-Induced Deformation Along A Passive Continental Margin, Ali A. Al Dhamen
LSU Master's Theses
Kinematic analysis of faults along the northern coastal plain of the Gulf of Mexico shows a correlation between pulses of faulting during the late Cenozoic and changes in the tectonic and climatic settings acting on the source areas which provide sediments to the Gulf. Pulses of faulting during the Oligocene-Early Miocene, Late Miocene, Pliocene, and Pleistocene correlate to major tectonic and climatic changes in the source region of sediments. Slip rates of faulting increase with younger events. The increase in slip rates is likely related to a combination of increase in sedimentation rates and pre-weakened Oligocene –Miocene rock that resulted …
Variations In Salinity And Temperature On The Flank Of An Offshore Louisiana Salt Structure, Candice M. Mccollum
Variations In Salinity And Temperature On The Flank Of An Offshore Louisiana Salt Structure, Candice M. Mccollum
LSU Master's Theses
Sediments located in the vicinity of salt structures in the northern Gulf of Mexico have highly complex structures and fluid dynamics associated with the dissolution and diapirism of salt. Past studies (Lin and Nunn, 1997; Bruno and Hanor, 2003; Richards, 2013) have shown that faults associated with salt structures can act both as migration pathways and barriers to the flow of formation waters. Bruno and Hanor (2003), Steen et al. (2011), and Richards (2013) also demonstrated that lithology was a controlling factor in the flow of formation waters. In this study, two sets of wireline logs, one used in salinity …
Palynology Of The Upper Cretaceous Ferron-Notom Sandstone, Utah, Isil Akyuz
Palynology Of The Upper Cretaceous Ferron-Notom Sandstone, Utah, Isil Akyuz
LSU Master's Theses
ABSTRACT The Late Cretaceous Ferron-Notom Sandstone Member of the Mancos Shale Formation plays a dominant role in oil production in Utah. Although numerous sedimentological and sequence stratigraphic studies have been conducted in recent years on this sequence, palynological analyses had not yet been undertaken. Here we present palynological data from one hundred twenty eight samples collected in the Ferron-Noton Sandstone Member outcroping in south-central Utah. The purpose of this study is to refine our understanding of climatic and depositional environments and to build a biostratigraphic palynological framework. The dominance of terrestrial palynomorphs, especially the high yield in moisture-loving cryptogam spores …
Evaluation Of Stromatolites From The 3.4 Ga Kromberg Formation, Barberton Greenstone Belt, South Africa, Corey E. Shircliff
Evaluation Of Stromatolites From The 3.4 Ga Kromberg Formation, Barberton Greenstone Belt, South Africa, Corey E. Shircliff
LSU Master's Theses
Silicified sedimentary rocks from the 3.4 Ga Kromberg Formation of the Barberton Greenstone Belt in South Africa contain laminated structures that have been identified as possible stromatolites in the field. Morphological evaluation and a variety of chemical analyses are presented here, in an effort to describe the samples in a sedimentary context and consider biogenicity of these laminated forms. Two major types of laminated structures were identified in the field – domical laminates and flat-laminated samples with little to no synoptic relief. The domical sample presents the best morphological evidence for biogenicity. There are several characteristics that suggest the deposition …
Paleoclimatology And Paleotempestology Study Of Blue Hole, Lighthouse Reef, Belize Through Geochemical Proxies, Laura Carolyn Sorey
Paleoclimatology And Paleotempestology Study Of Blue Hole, Lighthouse Reef, Belize Through Geochemical Proxies, Laura Carolyn Sorey
LSU Master's Theses
A large Pleistocene age sinkhole, the Blue Hole on Lighthouse Reef off the coast of Belize in the Caribbean Sea is the site of a well preserved sedimentary record that serves as paleoclimatology and paleotempestology archive. The nutrient-starved surface waters of the Blue Hole and the surrounding lagoons are “fertilized” by the seasonal introduction of cool, nutrient-rich waters upwelled from the Caribbean deep water. These waters, which stimulate production of organic materials within the surface waters, carry a heightened isotopic signature that is imparted to the organics resultant from upwelling-induced production. These organics are then incorporated into the predominantly carbonate …
Preliminary Investigation Of The Geometry And Kinematics Of The Bangong-Nujiang Suture At The Basu Metamorphic Massif, Se Tibet, Chase Michael Billeaudeau
Preliminary Investigation Of The Geometry And Kinematics Of The Bangong-Nujiang Suture At The Basu Metamorphic Massif, Se Tibet, Chase Michael Billeaudeau
LSU Master's Theses
There are many uncertainties associated with the development and deformation of the Tibetan Plateau. The Basu Massif, located along the eastern Bangong-Nujiang Suture Zone, is an ideal locality to help provide constraints to resolve the geologic evolution of the Tibetan Plateau. The Basu Massif is characterized by high pressure-ultra high pressure (HP-UHP) metamorphic rocks, syn- and post-collisional granites, and a central Upper Paleozoic unit bounded by discontinuous belts of serpentinite. Field data suggests that the carbonates of the central Upper Paleozoic unit, serpentinites, granites and metasedimentary rocks are part of an isoclinally folded shear zone that may have been thrust …
Channel-Levee Complexes And Sediment Flux Of The Upper Indus Fan, Taylor Landry Berlin
Channel-Levee Complexes And Sediment Flux Of The Upper Indus Fan, Taylor Landry Berlin
LSU Master's Theses
The Indus Fan with a volume of 4.5 million km³ is the second largest submarine fan on Earth, only behind its neighbor to the east The Bengal Fan. It formed off the passive margin of Pakistan-India in the northern Arabian Sea. One of the more important aspects of the Indus Fan is its mostly complete sediment record of what has been eroded from the western Himalayan and Karakoram Mountains which act as the main source for the Indus River system. Since the initiation of the Himalaya about 50 Ma, sedimentation rates have fluctuated. This study attempts to calculate a new …
Modeling Near Surface, Gas-Induced Seafloor Deformation Using Thin Plate Mechanics In The Thunder Horse Oil Field, Gulf Of Mexico And Ninilchik Field, Cook Inlet Basin, Alaska, Michael I. Thoma
LSU Master's Theses
Seabed topographic expressions such as pockmarks and domes caused by the vertical migration and accumulation of methane are found in muddy, cohesive sea beds around the world. These surface features range from 10-1000 m in diameter and 1-20 m in relief (Judd and Hovland, 2007). The mechanics of soft, cohesive sediment deformation due to overpressure from rising gas is not well understood or quantitatively defined despite the hazards they present to offshore drilling. Shallow gas pockets and overpressured sediments formed by the migration of subsurface gas to the seafloor can cause drilling blowouts, resulting in the release of large amounts …
Changes In Climate And Moisture Availability In The Antarctic Eocene, Oligocene, And Miocene: Evidence From Palynological And Stable Isotope Geochemical Analyses Of The Shaldril And Andrill Cores, Kathryn Whitney Griener
Changes In Climate And Moisture Availability In The Antarctic Eocene, Oligocene, And Miocene: Evidence From Palynological And Stable Isotope Geochemical Analyses Of The Shaldril And Andrill Cores, Kathryn Whitney Griener
LSU Doctoral Dissertations
Prior to the Late Eocene, the Antarctic continent experienced lush vegetation under temperate conditions. Just before the Eocene/Oligocene Boundary, the climate of the southernmost continent began to deteriorate dramatically. This cooling trend largely continued until most Antarctic vegetation disappeared, ~13.85-12.8 Ma. Classifying the nature and cause of Antarctica’s drastic climate change is essential for furthering our knowledge of Earth’s history, and also for grasping the potential effects of current and future climate shifts. Here, I present evidence from three new palynomorph-centric studies that deepen our understanding of Antarctic earth science, climate change, and of climate proxies. The first study involved …
Contractional Tectonics: Investigations Of Ongoing Construction Of The Himalaya Fold-Thrust Belt And The Trishear Model Of Fault-Propagation Folding, Hongjiao Yu
LSU Doctoral Dissertations
This dissertation focuses on the kinematic evolution of contractional tectonics: the Himalayan fold-thrust belt along the collisional orogenic belts, and growth of the basement-cored monoclines in Colorado Plateau. Ongoing Himalayan growth is generally thought to be dominated by duplexing and/or extrusion processes. Duplexing models highlight accretion of material from the subducting plate to the over-riding orogenic wedge, whereas extrusion models focus on up-dip translation of a block bounded by out-of-sequence faults. Here, a primary outstanding question involves the uncertain relationship of the Berinag thrust and the Tons thrust, structures with displacements of >80 km and >40 km, respectively. The uncertainty …
Untangling Earth System Responses Recorded In Sulfate's Sulfur And Oxygen Isotopes At The Dawn Of Multicellular Life And Today, Bryan Alan Killingsworth
Untangling Earth System Responses Recorded In Sulfate's Sulfur And Oxygen Isotopes At The Dawn Of Multicellular Life And Today, Bryan Alan Killingsworth
LSU Doctoral Dissertations
Major Earth system perturbations in the deep past and today are recorded in sulfate sulfur and oxygen isotopes, as examined here in three cases. (1) Sedimentary sulfate record of the “Marinoan Oxygen-17 Depletion” (MOSD) event, implies ultra-high CO2 atmosphere at ~635 Ma after global glaciation. MOSD duration is constrained by correlating its most complete record to radiometric dates. Barium sulfate layers in South China sediments show the MOSD in lower layers but persistently absent up section. Carbon-13 correlation locates the MOSD within dated intervals from other sites, yielding a 0 - 0.99 Myr duration. Thus, sedimentary constraint on this non-steady-state …
Consolidation And Suspension Of Mud From Lake Lery And Relevance To Wetland Restoration In Louisiana, Edward L. Lo
Consolidation And Suspension Of Mud From Lake Lery And Relevance To Wetland Restoration In Louisiana, Edward L. Lo
Honors Capstones
No abstract provided.
Microbially Mediated Carbonate Precipitation Within Microbial Mat In Hyper-Saline Lakes Of The Bahamas, Shane Cone
Microbially Mediated Carbonate Precipitation Within Microbial Mat In Hyper-Saline Lakes Of The Bahamas, Shane Cone
Honors Capstones
No abstract provided.
Reinterpreting The Stratigraphy Of The Florissant Fossil Beds National Monument Through Correlation By Magnetic Susceptibility And Geochemical Comparison, Lindsay Prothro
Reinterpreting The Stratigraphy Of The Florissant Fossil Beds National Monument Through Correlation By Magnetic Susceptibility And Geochemical Comparison, Lindsay Prothro
Honors Capstones
No abstract provided.
Predicting Potential Unconventional Production In The Tuscaloosa Marine Shale Play Using Thermal Modeling And Log Overlay Analysis, Hunter Berch
LSU Master's Theses
The Tuscaloosa Marine Shale formation (TMS) of Central Louisiana and South Mississippi was suggested as a potential hydrocarbon play with up to seven billion barrels of reserves in a 1997 study by Louisiana State University’s Basin Research Institute. The TMS is considered an unconventional resource because it is a source, reservoir, and seal. Since 1997, horizontal drilling and hydraulic fracturing have enabled exploration and documentation of oil reserves in this play. Prior to this study, high resistivity log curves were used to predict areas of economic interest. While areas of high resistivity within the TMS are often indicative of high …
On The Long Duration Of Till Sheet Construction : A Reassessment Of How Quaternary Grounding Line Translations Relate To Near-Surface Seismic-Stratigraphy Of Eastern Ross Sea, Antarctica, Sydney Grace Bowles
On The Long Duration Of Till Sheet Construction : A Reassessment Of How Quaternary Grounding Line Translations Relate To Near-Surface Seismic-Stratigraphy Of Eastern Ross Sea, Antarctica, Sydney Grace Bowles
LSU Master's Theses
Previously acquired seismic surveys provide strong evidence that the post-Last Glacial Maximum (LGM) retreat of the West Antarctic Ice Sheet (WAIS) deposited a back-stepping succession of seismically-resolved grounding zone wedges (GZWs) in eastern Ross Sea. However, the chronology of WAIS retreat is debated. The conventional view is that three GZWs (Red, Brown, and Gray Units) were deposited since the LGM. An alternative view, based on recent radiocarbon dates, is that the youngest GZW (the Gray Unit) was deposited during the LGM. If correct, then the older GZWs (Red and Brown Units) were deposited prior to LGM. A recent study (Bart …
Temporal And Spatial Variations In The Subsurface Salinity Of Lake Charles, Louisiana : An Investigation Of Saline Sources, Alexandria Suding
Temporal And Spatial Variations In The Subsurface Salinity Of Lake Charles, Louisiana : An Investigation Of Saline Sources, Alexandria Suding
LSU Master's Theses
One of the most pressing issues facing groundwater managers is saltwater intrusion. In coastal Louisiana this issue is especially prevalent. One location that is currently threated by saltwater intrusion is the industrial area of Lake Charles, Louisiana, where three high chloride areas have been detected within the underlying Chicot aquifer. Three sand units of the Chicot aquifer are present in Lake Charles: the 200-foot (200’) sand, the 500’ sand, and the 700’ sand. Groundwater with elevated chloride concentrations was first noticed by industries in the early 1970s. An initial investigation determined that the northern and southern bodies had formed by …
Evaluating Quaternary Glacial Till Sheet Volume And Duration Of Grounding Events Using Sediment Flux Calculations In The Eastern Basin Paleotroughs, Ross Sea, Anarctica, Logan Gregory Kirst
Evaluating Quaternary Glacial Till Sheet Volume And Duration Of Grounding Events Using Sediment Flux Calculations In The Eastern Basin Paleotroughs, Ross Sea, Anarctica, Logan Gregory Kirst
LSU Master's Theses
A sequence of three seismically-resolvable, back-stepping grounding zone wedges (GZWs) within the Glomar-Challenger Basin paleo-ice-stream trough is conventionally interpreted to have been deposited by the West Antarctic Ice Sheet (WAIS) since the end of the Last Glacial Maximum (LGM). For this to be true, there would have to have been voluminous GZW deposition via fast moving ice streams with high sediment flux during the short timeframe since the WAIS retreat began at 11 Ka 14C BP and when the WAIS moved south of Roosevelt Island at 3.2 Ka BP. In contrast to this interpretation of how the near-surface stratigraphy relates …
The Reduction And Reoxidation Of Ceria : A Natural Abundance Oxygen Isotope Approach, Justin Alan Hayles
The Reduction And Reoxidation Of Ceria : A Natural Abundance Oxygen Isotope Approach, Justin Alan Hayles
LSU Master's Theses
Ceria (CeO2) is a fluorite type oxide that has been used extensively as an oxygen storage media in three-way catalysts, as an oxygen partial pressure regulator, as a fuel additive for the reduction of soot and for the production of syn-gas from water and carbon dioxide. It is known that exposing ceria powders to low pO2 and/or high temperature conditions will cause ceria to partially reduce. This partial reduction leads to the formation of oxygen vacancies, which up to a limit, do not significantly influence the crystal structure. When partially reduced ceria is exposed to high pO2 environments, such as …
Metamorphic And Geochemical Signatures Of Calc-Silicate Gneisses From The Sawtooth Metamorphic Complex, Idaho, Usa : Implications For Crustal Evolution In Western North America, Isis Fukai
LSU Master's Theses
The Sawtooth Metamorphic Complex (SMC) of central Idaho contains exposures of metasupracrustal rocks that may provide constraints on Precambrian crustal evolution in northwestern United States. Petrographic textures, whole-rock geochemistry, and thermobarmetry of SMC calc-silicate gneisses, collected at high-resolution, record multiple stages of crustal development, including: contiguous deposition of a sandstone-to-shale sequence derived from post-Archean continental sediments, metamorphism during two medium-high-grade thermal events (M1, M2), and two distinct episodes of deformation (D1, D2). Whole-rock concentrations of Cr (23.97-76.43 ± 3.0 ppm), Ni (6.82-33.10 ± 3.5 ppm), Th (2.11-12.04 ± 1.6 ppm), Sc (3.81-11.53 ± 1.6 ppm), and Zr (322-658 ± 3.9 …
Natural Fracture Characterization In The Haynesville Shale, East Texas: A Core Study, Frank Leslie Morgan
Natural Fracture Characterization In The Haynesville Shale, East Texas: A Core Study, Frank Leslie Morgan
LSU Master's Theses
The Haynesville Shale in East Texas and Northwest Louisiana is one of the most studied and explored shale-gas plays in the United States. With new horizontal drilling and completion strategies, energy companies can produce hydrocarbons directly from the source rock making the Haynesville Shale an attractive resource. A key component of enhanced hydrocarbon production is the presence of natural fractures. They may serve as permeable pathways for hydrocarbon flow, especially in tight shales such as in the Haynesville Shale, where the matrix permeability is very low. In the case of the Haynesville Shale, little is known about the occurrence of …
Controls On The Composition Of Saline Formation Waters From Coastal And Offshore Louisiana, Marielle Elaine Ausburn
Controls On The Composition Of Saline Formation Waters From Coastal And Offshore Louisiana, Marielle Elaine Ausburn
LSU Master's Theses
Geothermal energy is a renewable energy source that can contribute to the U.S. energy mix. As such, new technologies are being explored for lower temperature systems which would open new areas for exploration in Louisiana. Unlike concepts proposed in the early 1980s, in which heat would have been extracted at the land surface from produced overpressured waters, methods currently being proposed would involve engineered down-hole heat exchangers with zero-mass-fluid withdrawal. A re-examination has been made of the controls on the composition of formation waters in south central and offshore Louisiana in the context of providing insight into water-rock reactions that …
High Resolution Tephra And U/Pb Chronology Of The 3.33 – 3.26 Ga Mendon Formation, Barberton, Greenstone Belt, South Africa, Nicholas Burns Decker
High Resolution Tephra And U/Pb Chronology Of The 3.33 – 3.26 Ga Mendon Formation, Barberton, Greenstone Belt, South Africa, Nicholas Burns Decker
LSU Master's Theses
The Mendon Formation in the Barberton Greenstone Belt of South Africa marks the boundary between the Onverwacht and Fig Tree Groups. These groups are characterized by mafic to ultramafic volcanism and felsic volcanism with related epiclastic sedimentation, respectively. This transition marks the end of komatiitic volcanism in the Barberton Greenstone Belt and is accompanied by numerous impact-related spherule layers. This study characterizes the upper Mendon Formation texturally and geochemically over a wide areal extent and across structure and facies change in an attempt to better understand the evolution of tectonic processes at this boundary. A suite of whole rock and …
Subsurface Stratigraphic Architecture Of Pleistocene Sediments In The Greater New Orleans Area, James Ayrer
Subsurface Stratigraphic Architecture Of Pleistocene Sediments In The Greater New Orleans Area, James Ayrer
LSU Master's Theses
A major environmental and economic problem currently faces the New Orleans area, in southeastern Louisiana, stemming from salinization of freshwater aquifers that are important resources for the community. Major pumping of these aquifers has altered the potentiometric flow, allowing saltier bodies of water to flow into the region. The impact of pumping wells on encroachment of saltwater and the time as well as the route for saltwater to travel from the current saltwater-freshwater interface to pumping centers is not well constrained. Water planners need additional information to make decisions about future management of groundwater resources. The most effective way to …
Spatial Variations In Salinity And Temperature Around The Bay Marchand Salt Dome, Offshore Louisiana, Laurie Richards
Spatial Variations In Salinity And Temperature Around The Bay Marchand Salt Dome, Offshore Louisiana, Laurie Richards
LSU Master's Theses
The Bay Marchand field is located about 60 miles south of New Orleans, Louisiana on the continental shelf. The structurally complex field has produced over 960 MMBOE as of 2012 (http://www.eplweb.com), with many of these hydrocarbons being trapped against the massive salt dome and associated faulting present in the area. A study by Bruno and Hanor (2003) documented the presence of a high salinity plume off the southeast flank of the dome that had less saline and less dense pore water below it. The purpose of this study was to investigate the spatial variations in pore water salinity and temperature …
Evaluation Of Thermal Insulation By Coal Beds In The Western Arkoma Basin, Ok And Implications For Large Scale Geothermal Resources, Matthew Freeman
Evaluation Of Thermal Insulation By Coal Beds In The Western Arkoma Basin, Ok And Implications For Large Scale Geothermal Resources, Matthew Freeman
LSU Master's Theses
Weighted average geothermal gradients in the Western Arkoma Basin, Oklahoma are estimated from bottom hole temperatures (BHT) from 158 oil and gas wells. The regional geothermal gradient is 28.8 °C/km. The central and north central portions of the basin have higher gradients than southern and northern portions, especially in large areas of Pittsburg and Haskell counties where geothermal gradients in excess of 36 °C/km exist. These gradients suggest that temperatures suitable for low temperature geothermal power exist at depths of 2-3 km. Coals have very low thermal conductivity (0.15 – 0.5 W/m°K) acting as thermal insulators. This study examines the …
A Clay Mineral Provenance Study Of The Northern Pandora Trough Continental Margin, Gulf Of Papua, Ashley Len Howell
A Clay Mineral Provenance Study Of The Northern Pandora Trough Continental Margin, Gulf Of Papua, Ashley Len Howell
LSU Master's Theses
X-ray diffraction mineralogy of western-, central-, and eastern-derived fluvial sediments within the Gulf of Papua exhibits distinct and mixed clay mineral assemblages. These mineral assemblages allow for a better understanding of how a thick muddy continental margin shelf-edge depocenter in the eastern Gulf of Papua of latest Pleistocene/early Holocene age formed, as well as connections between terrestrial sediment delivery and evolution of deep-sea deposits in this region. Modern clay mineralogy reveals a high to low gradation of illite/smectite values from the western to eastern Gulf of Papua (Slingerland et al., 2008a), which is applied to the recent past for provenance …