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Articles 1 - 30 of 46
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Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel
Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel
LSU Master's Theses
I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …
Climate And Atlantic Sea-Level Recorded In Southwestern Spain From 6.3 To 5.2 Ma. Inferences On The Messinian Crisis In The Mediterranean, Jean Pierre Suc, Séverine Fauquette, Sophie Warny, Gonzalo Jiménez-Moreno, Damien Do Couto
Climate And Atlantic Sea-Level Recorded In Southwestern Spain From 6.3 To 5.2 Ma. Inferences On The Messinian Crisis In The Mediterranean, Jean Pierre Suc, Séverine Fauquette, Sophie Warny, Gonzalo Jiménez-Moreno, Damien Do Couto
Faculty Publications
The Mio-Pliocene succession of Andalusia on the Atlantic coast (Guadalquivir Basin) is known as one of the former stratotype candidate for the Andalusian Stage, proposed during the seventies as the last stage of the Miocene. Its type section is located in Carmona, east of Seville. Our investigation includes the drilling of three cored boreholes, which provide bio- and magnetic-stratigraphic data in complement to pre-existing industrial information, and a high-resolution palynological analysis (pollen grains, spores and dinoflagellate cysts). The pollen flora and its climatic quantification provide the mean to correlate the section to the oxygen isotope curve from the Montemayor-1 borehole, …
Characterization Of Gas Hydrate Formation And Its Impact On Slope Stability In Offshore Environments, Sulav Dhakal
Characterization Of Gas Hydrate Formation And Its Impact On Slope Stability In Offshore Environments, Sulav Dhakal
LSU Doctoral Dissertations
Natural gas hydrates (NGH) are predominantly methane hydrates formed at high pressure and low temperature conditions typically in submarine sediments and permafrost. This dissertation is focused on the submarine methane hydrates formed by upward migration of free and dissolved gas. The methane gas stored within natural hydrates has more energy potential than all the combined oil and gas resources around the world. Numerical simulation of fluid flow, heat transport, and geomechanical stresses is used to characterize and evaluate the saturation, distribution, reservoir quality, and geohazards associated with hydrate-bearing sediments. Coupled thermo-hydro-mechanical (THM) simulation of hydrate formation, dissociation, and slope stability …
Connectivity And Directionality In Estuarine Channel Networks, Matthew Hiatt, Elisabeth A. Addink, Maarten G. Kleinhans
Connectivity And Directionality In Estuarine Channel Networks, Matthew Hiatt, Elisabeth A. Addink, Maarten G. Kleinhans
Faculty Publications
No abstract provided.
Snapshots Of Pre-Glacial Paleoenvironmental Conditions Along The Sabrina Coast, East Antarctica: New Palynological And Biomarker Evidence, Meghan Duffy, Emily J. Tibbett, Catherine Smith, Sophie Warny, Sarah J. Feakins, Gilles Escarguel, Rosemary Askin, Amy Leventer, Amelia E. Shevenell
Snapshots Of Pre-Glacial Paleoenvironmental Conditions Along The Sabrina Coast, East Antarctica: New Palynological And Biomarker Evidence, Meghan Duffy, Emily J. Tibbett, Catherine Smith, Sophie Warny, Sarah J. Feakins, Gilles Escarguel, Rosemary Askin, Amy Leventer, Amelia E. Shevenell
Faculty Publications
The Aurora Subglacial Basin (ASB) catchment contains 3–5 m of sea-level equivalent ice volume that drains to the Sabrina Coast, East Antarctica via the Totten Glacier system. Observed thinning and retreat of Totten Glacier indicate regional sensitivity to oceanographic and atmospheric warming. Paleoclimate studies of climatically sensitive catchments are required to understand the evolution of the East Antarctic Ice Sheet (EAIS) and its outlet glacier systems. Recent seismic and sediment studies from the Sabrina Coast document the evolution of the EAIS in the ASB catchment, suggesting that the region has long been sensitive to climatic changes. This study presents new …
Isotopic Fingerprints Of Mountain Uplift And Global Cooling In Paleoclimatic And Paleoecological Records From The Northern Tibetan Plateau, Mingqiu Hou, Guangsheng Zhuang, Minghao Wu
Isotopic Fingerprints Of Mountain Uplift And Global Cooling In Paleoclimatic And Paleoecological Records From The Northern Tibetan Plateau, Mingqiu Hou, Guangsheng Zhuang, Minghao Wu
Faculty Publications
Post-middle Miocene changes in climate and ecology in the northern Tibetan Plateau have been attributed to tectonic uplift and global climate change. However, the relative roles of tectonism and global climate change have been a long-standing debate. To untangle the complex influences of global climate change versus the tectonism on regional climate and ecology in the northern Tibetan Plateau, we studied carbon isotopes (δ13Cwax) of leaf wax long-chain n-alkanes and carbon (δ13C) and oxygen isotopes (δ18O) of carbonates from three stratigraphic successions (ca. 16 Ma to 2 Ma) in the Hexi Corridor (foreland basin) …
Simulating Hydrological Connectivity And Water Age Within A Coastal Deltaic Floodplain Of The Mississippi River Delta, Alexandra Christensen, Robert R. Twilley, Clinton S. Willson, Edward Castañeda-Moya
Simulating Hydrological Connectivity And Water Age Within A Coastal Deltaic Floodplain Of The Mississippi River Delta, Alexandra Christensen, Robert R. Twilley, Clinton S. Willson, Edward Castañeda-Moya
Faculty Publications
Located at the mouth of large rivers, coastal deltaic floodplains are important ecosystems for trapping sediment and removing excess nitrogen introduced to the river through agricultural and urban runoff. Hydrological connectivity (the percent of river channel water interacting with floodplain wetlands), water age (the time elapsed since water entered the system via the main river channel) and water temperature have strong impacts on the biogeochemical processes controlling the fate of sediment and nutrients at continental margins. A Delft3D hydrodynamic model was used to explore the role of river and tide forcings, hydrogeomorphology, and vegetation roughness on hydrological connectivity, water age, …
Seismic Ground Motion Data Analyses For North-East Arkansas, Zahid Hossain Ph.D, Ashraf Elsayed Ph.D, Md Ariful Hasan, Md Rafiue Islam
Seismic Ground Motion Data Analyses For North-East Arkansas, Zahid Hossain Ph.D, Ashraf Elsayed Ph.D, Md Ariful Hasan, Md Rafiue Islam
Publications
Estimation of liquefaction resistance and shear velocities are key elements in the assessment of potential earthquake damage of existing and new construction sites. The Arkansas Department of Transportation (ARDOT) and other agencies in the region need ground motion response analysis (GMRA) data of specific construction sites. As part of a recent ARDOT’s Transportation Research Committee (TRC) project, researchers have conducted geophysical investigations several construction sites in northeast Arkansas over the past twelve years. The current study gathered the previously reported test data and estimated seismic hazard properties such as shear wave velocity profiles and seismic hazard coefficients for nearby locations. …
Salt Marsh Dynamics In A Period Of Accelerated Sea Level Rise, Sergio Fagherazzi, Giulio Mariotti, Nicoletta Leonardi, Alberto Canestrelli, William Nardin, William S. Kearney
Salt Marsh Dynamics In A Period Of Accelerated Sea Level Rise, Sergio Fagherazzi, Giulio Mariotti, Nicoletta Leonardi, Alberto Canestrelli, William Nardin, William S. Kearney
Faculty Publications
Salt marshes are dynamic systems able to laterally expand, contract, and vertically accrete in response to sea level rise. Here, we present the grand challenges that need to be addressed to fully characterize marsh morphodynamics. The review focuses on physical processes and quantitative models. Without predictive models, it is impossible to determine the future marsh evolution under accelerated sea level rise. In these models, one of the challenges is to resolve both horizontal and vertical dynamics within the same framework. Vertically, the marsh has to accumulate enough material to contrast rising water levels. Horizontally, marsh erosion at the ocean side …
Review Of Naturally Occurring Ammonia In Groundwater And Its Effect On Using Chloramines For Drinking Water Disinfection In Louisiana, Athena Lindsay
Review Of Naturally Occurring Ammonia In Groundwater And Its Effect On Using Chloramines For Drinking Water Disinfection In Louisiana, Athena Lindsay
Honors Capstones
No abstract provided.
The Dual Role Of Amazonian Rivers In The Generation And Maintenance Of Avian Diversity, Luciano N. Naka, Robb T. Brumfield
The Dual Role Of Amazonian Rivers In The Generation And Maintenance Of Avian Diversity, Luciano N. Naka, Robb T. Brumfield
Faculty Publications
Copyright © 2018 The Authors. The Amazon River and its major tributaries delimit the distributions of hundreds of terrestrial taxa. It remains unclear whether river-bounded distributions and taxon replacements reflect the historical role of rivers in generating species diversity as vicariant forces, or are the result of their role as secondary barriers, maintaining current levels of species diversity by inhibiting gene flow and population introgression. We use a community-wide comparative phylogeographic and phylogenetic approach to address the roles that the Rio Negro and the Rio Branco play in the avian speciation process in the Guiana Shield. Examining 74 pairs of …
Sediment And Plant Dynamics In A Degrading Coastal Louisiana Landscape, Glenn Michael. Suir
Sediment And Plant Dynamics In A Degrading Coastal Louisiana Landscape, Glenn Michael. Suir
LSU Doctoral Dissertations
Alterations to Louisiana’s river systems and local hydrology have resulted in reduced freshwater, sediment, and nutrient inputs into wetland landscapes, causing significant negative impacts on marsh productivity and stability. To combat these losses many restoration projects have been constructed or planned throughout coastal Louisiana. Typical goals of wetland restoration efforts are to conserve, create, or enhance wetland form, and to achieve wetland function that approaches natural conditions. Failure to adequately maintain wetland elevation and hydrology can have serious implications on sedimentation and vegetation processes, which significantly reduces the likelihood of reaching structural and functional targets. Measures of wetland condition have …
Influences Of Hurricanes, Floods, And Organic Production On River-Delta Evolution Over Decadal To Centennial Time-Scales, Crawford M. White
Influences Of Hurricanes, Floods, And Organic Production On River-Delta Evolution Over Decadal To Centennial Time-Scales, Crawford M. White
LSU Doctoral Dissertations
Episodic overbank flooding and sediment resuspension events (such as cold front passages or tropical cyclones) are recognized as important natural components for wetlands maintaining vertical equilibrium with sea-level. However, the relative importance of these components to an anthropogenically unmodified delta complex remains unclear. This study uses sediment cores to describe the relative importance of these vertical accretion components the Lafourche and Balize Deltas of the Mississippi River. Existing wetlands of the abandoned lower Lafourche receive no direct fluvial sediment, but instead are supported by sediment resuspended by tropical cyclones and cold fronts that pass over them. Wetlands of the modern …
The Mississippi River Source-To-Sink System: Perspectives On Tectonic, Climatic, And Anthropogenic Influences, Miocene To Anthropocene, S. J. Bentley, M. D. Blum, J. Maloney, L. Pond, R. Paulsell
The Mississippi River Source-To-Sink System: Perspectives On Tectonic, Climatic, And Anthropogenic Influences, Miocene To Anthropocene, S. J. Bentley, M. D. Blum, J. Maloney, L. Pond, R. Paulsell
Faculty Publications
© 2015 Elsevier B.V. The Mississippi River fluvial-marine sediment-dispersal system (MRS) has become the focus of renewed research during the past decade, driven by the recognition that the channel, alluvial valley, delta, and offshore regions are critical components of North American economic and ecological networks. This renaissance follows and builds on over a century of intense engineering and geological study, and was sparked by the catastrophic Gulf of Mexico 2005 hurricane season, the 2010 Deep Water Horizon oil spill, and the newly recognized utility of source-to-sink concepts in hydrocarbon exploration and production. With this paper, we consider influences on the …
Post-Treatment Assessment Of Hydraulic Fracturing With Integrated Modeling Of Natural Fracture Distribution, Ping Puyang
Post-Treatment Assessment Of Hydraulic Fracturing With Integrated Modeling Of Natural Fracture Distribution, Ping Puyang
LSU Master's Theses
Hydraulic fracturing has been serving as the principal reservoir stimulation technique for decades to improve production capacities of low permeability formations. On the other hand, through core and outcrop studies, advanced logging tools, microseismic fracture mapping and well testing analysis, it has been further revealed that many of the shale gas formations are naturally fractured. The presence of natural fractures and their interactions with hydraulic fractures must be taken into consideration while designing fracturing treatment. Although most natural fractures are cemented by precipitations during diagenesis, they may be reactivated during hydraulic fracturing and serve as weak paths for fluid flow …
Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland
Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland
LSU Doctoral Dissertations
The northwest Gulf of Mexico (Gulf) shelf-edge banks both provide unique hard bottom habitat and support the northernmost coral reefs on the North American continental shelf in a region that is generally characterized by low relief, soft sediments. The habitat value of many of these banks has led to their designation as Habitat Areas of Particular Concern (HAPC) and the Flower Garden Banks National Marine Sanctuary (FGBNMS). However, little is known about the fisheries resources and dynamics of the banks outside the FGBNMS. This study had three main objectives: 1) define reef fish assemblages at northwestern Gulf shelf-edge banks and …
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 …
Holocene Evolution In Weathering And Erosion Patterns In The Pearl River Delta, Dengke Hu, Peter D. Clift, Philipp Böning, Robyn Hannigan, Stephen Hillier, Jerzy Blusztajn, Shiming Wan, Dorian Q. Fuller
Holocene Evolution In Weathering And Erosion Patterns In The Pearl River Delta, Dengke Hu, Peter D. Clift, Philipp Böning, Robyn Hannigan, Stephen Hillier, Jerzy Blusztajn, Shiming Wan, Dorian Q. Fuller
Faculty Publications
Sediments in the Pearl River delta have the potential to record the weathering response of this river basin to climate change since 9.5 ka, most notably weakening of the Asian monsoon since the Early Holocene (∼8 ka). Cores from the Pearl River delta show a clear temporal evolution of weathering intensity, as measured by K/Al, K/Rb, and clay mineralogy, that shows deposition of less weathered sediment at a time of weakening monsoon rainfall in the Early-Mid Holocene (6.0-2.5 ka). This may reflect an immediate response to a less humid climate, or more likely reduced reworking of older deposits from river …
Watershed Land Use And River Engineering Drive Wetland Formation And Loss In The Mississippi River Birdfoot Delta, A W. Tweel, R. Eugene Turner
Watershed Land Use And River Engineering Drive Wetland Formation And Loss In The Mississippi River Birdfoot Delta, A W. Tweel, R. Eugene Turner
Faculty Publications
The Mississippi River basin was developed for agriculture at an unprecedented scale and intensity within the last 200 yr. These changes favored erosion and sediment transport, which were subsequently reduced by soil conservation practices, the trapping of sediment behind large reservoirs, and channel engineering. We discuss the relationship between sediment loading and the growth, loss, and stability of wetlands in the Mississippi River birdfoot delta (MRBD). We report an anthropogenically driven increase in mean suspended sediment concentrations in the Mississippi River below New Orleans, from a modeled 350 mg L-1 (174 x 10(9) kg yr(-1)) at the end of the …
Lineage Diversification And Morphological Evolution In A Large-Scale Continental Radiation: The Neotropical Ovenbirds And Woodcreepers (Aves: Furnariidae), Elizabeth P. Derryberry, Santiago Claramunt, Graham Derryberry, R. Terry Chesser, Joel Cracraft, Alexandre Aleixo, Jorge Pérez-Emán, J. V. Remsen, Robb T. Brumfield
Lineage Diversification And Morphological Evolution In A Large-Scale Continental Radiation: The Neotropical Ovenbirds And Woodcreepers (Aves: Furnariidae), Elizabeth P. Derryberry, Santiago Claramunt, Graham Derryberry, R. Terry Chesser, Joel Cracraft, Alexandre Aleixo, Jorge Pérez-Emán, J. V. Remsen, Robb T. Brumfield
Faculty Publications
Patterns of diversification in species-rich clades provide insight into the processes that generate biological diversity. We tested different models of lineage and phenotypic diversification in an exceptional continental radiation, the ovenbird family Furnariidae, using the most complete species-level phylogenetic hypothesis produced to date for a major avian clade (97% of 293 species). We found that the Furnariidae exhibit nearly constant rates of lineage accumulation but show evidence of constrained morphological evolution. This pattern of sustained high rates of speciation despite limitations on phenotypic evolution contrasts with the results of most previous studies of evolutionary radiations, which have found a pattern …
Coastal Land Loss And Hypoxia: The 'Outwelling' Hypothesis Revisited, Anindita Das, Dubravko Justic, Erick M. Swenson, R. Euigene Turner, Masamichi Inoue, Dongho Park
Coastal Land Loss And Hypoxia: The 'Outwelling' Hypothesis Revisited, Anindita Das, Dubravko Justic, Erick M. Swenson, R. Euigene Turner, Masamichi Inoue, Dongho Park
Faculty Publications
It is generally believed that interannual variability in the areal extent of the Gulf of Mexico hypoxia is driven primarily by the magnitude of the Mississippi River freshwater and nutrient fluxes. It has recently been proposed that outwelling of carbon from deteriorating coastal wetlands into the surrounding Gulf of Mexico could be an important mechanism promoting the development of hypoxia. We used a coupled hydrology-hydrodynamics model of the Barataria estuary, a site of massive wetland loss, to calculate the fluxes of nitrogen, chlorophyll a and carbon at the estuary-ocean interface. The hydrology model calculates runoff from rainfall and evaporation data, …
Geological Analysis And Hydrodynamic Modeling Of Tropical Cyclone Influence: Northeastern Gulf Of Mexico Inner Shelf, Amy Lynn Spaziani
Geological Analysis And Hydrodynamic Modeling Of Tropical Cyclone Influence: Northeastern Gulf Of Mexico Inner Shelf, Amy Lynn Spaziani
LSU Master's Theses
The need to characterize offshore resources as borrow areas for beach restoration has initiated interest of the impact of storms to the inner continental shelf. While numerous studies have investigated the response of coastal systems to major storms, very little is known about the geological response of inner shelves to frequent and intense storms. This approach integrated a geological study with modeling of hydrodynamics during recent storms, in order to relate trends in the geological signature to physical forcing mechanisms during storms. First, waves and hydrodynamic conditions were modeled during two major recent storms that made landfall in the northeastern …
Saint Maló Remembered, Erin Elizabeth Voisin
Saint Maló Remembered, Erin Elizabeth Voisin
LSU Master's Theses
This research explores the unique process of creolization that occurred in Southern Louisiana through the development of the figure of San Maló over time. His transformation from historic rebel to religious icon takes place through the devices of folklore, poetry, and song. This developmental process of a culture redefining its heroes through oral tradition represents the dynamism of creolization. The transformative process of San Maló serves as an exemplary representation of how a culture negotiates its own history with what is deemed necessary and beneficial to the culture’s survival. All information on this transformation was gathered through historic research and …
Sediment Flux And Fate In The Mississippi River Diversion At West Bay: Observation Study, T. Mitchell Andrus, Samuel J. Bentley
Sediment Flux And Fate In The Mississippi River Diversion At West Bay: Observation Study, T. Mitchell Andrus, Samuel J. Bentley
Faculty Publications
Land-building sediment diversions, such as the Mississippi River Diversion at West Bay, are being used as important building blocks in the conservation and restoration of Mississippi Delta wetlands. We have studied sediment deposition and retention in the West Bay diversion outfall area through analyses of sediment cores, bathymetry, and hydrodynamics. Cores and x-ray samples were collected at twenty stations in March 2004, August 2004, November 2005, and April 2006. Cores were sub-sampled in 2 cm increments and analyzed for grain size distributions and 7Be activities which can be linked to recent sediment deposition. Bathymetric surveys were conducted in November 2005 …
Sediment Flux And Fate In The Mississippi River Diversion At West Bay: Observation Study, Thomas Mitchell Andrus
Sediment Flux And Fate In The Mississippi River Diversion At West Bay: Observation Study, Thomas Mitchell Andrus
LSU Master's Theses
Land-building sediment diversions, such as the Mississippi River Diversion at West Bay, can be used as important building blocks in the conservation and restoration of Mississippi Delta wetlands. Sediment deposition and retention patterns were studied in the West Bay diversion outfall area through analyses of sediment cores, hydrodynamics, and bathymetry. Cores and x-ray samples were collected at twenty stations in March 2004, August 2004, November 2005, and April 2006. Cores were analyzed for grain-size distributions and 7Be activities, in order to examine patterns of recent sediment deposition. In comparing ratios of total 7Be inventory to atmospheric 7Be …
Tourmalinities In Neoproterzoic Metaevaporitic Deposit Of Duruchas Formation, Damar Belt, Central Namibia, Haiting Sun
Tourmalinities In Neoproterzoic Metaevaporitic Deposit Of Duruchas Formation, Damar Belt, Central Namibia, Haiting Sun
LSU Doctoral Dissertations
Tourmalinites from a well-developed meta-evaporite sequence in the Neoproterozoic Duruchaus Formation of central Namibia contain tourmalines with chemical and textural features that are excellent recorders of their environment of formation. Unlike most other meta-evaporitic deposits, this tourmalinite locality exhibits only minor deformation. The tourmalinites form as finely laminated units ca. 1 m thick within a sequence of quartzites, mica schists, dolomitic marbles, and carbonate breccias. Well-preserved pseudomorphs are considered to replace a variety of evaporitic minerals. The meta-sedimentary rocks of the Duruchaus Formation have been interpreted as representing lacustrine, playa lake, fluvial, and non-marine evaporite deposition in an intracontinental rift …
Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman
Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman
LSU Master's Theses
A method was developed to simplify the approach to obtaining a better quantitative representation (QR) of complex clay mineral assemblages by XRD analysis. The method has eight steps: 1) preparation of samples with preferred orientation; 2) qualitative identification of phases; 3) peak decomposition to obtain precise locations of individual peaks contained within broad diffraction bands; 4) creation of a library of theoretical XRD patterns by modeling of one-dimensional XRD patterns; 5) selection of experimental library patterns; 6) employing the LINEST function found in common spreadsheet software to fit library patterns to experimental patterns; 7) evaluation of results to determine needed …
Systematics Of The Western Lyresnake (Trimorphodon Biscutatus) Complex: Implications For North And Middle American Aridland Biogeography, Thomas James Devitt
Systematics Of The Western Lyresnake (Trimorphodon Biscutatus) Complex: Implications For North And Middle American Aridland Biogeography, Thomas James Devitt
LSU Master's Theses
The Western Lyresnake (Trimorphodon biscutatus) is found generally from the desert southwestern United States southward along the pacific lowland versant of Mexico to northwestern Costa Rica. This species exhibits substantial geographic variation in size, squamation, and color pattern across its range, and as such has had an unstable taxonomic history. I investigated populations of T. biscutatus representing currently and formerly recognized forms using both morphological and molecular methods to infer the evolutionary history of this widespread, polytypic taxon. Multivariate statistical analyses (principal components and discriminant analysis) of morphological data (432 specimens, 33 characters) yielded six statistically significantly different groups, consistent …
Uncovering Strata: An Investigation Into The Graphic Innovations Of Geologist Henry T. De La Beche, Renee M. Clary
Uncovering Strata: An Investigation Into The Graphic Innovations Of Geologist Henry T. De La Beche, Renee M. Clary
LSU Doctoral Dissertations
An historical investigation into the types of illustrations in the Golden Age of Geology (1788-1840) revealed the nature and progression of graphic representation at the dawning of geology as a science. Exhaustive sampling of geology texts published in the period of focus proceeded until saturation was achieved. Qualitative analysis and evaluation of early illustrations were accomplished with Edward R. Tufte's theory of graphic design. Hypothesis testing around a correlation coefficient revealed significance at the 99% confidence level for relationships between publication year and number of included graphics, and publication year and the graphic density of texts. Henry T. De la …
Analytical Study On Flood Induced Seepage Under River Levees, Senda Ozkan
Analytical Study On Flood Induced Seepage Under River Levees, Senda Ozkan
LSU Doctoral Dissertations
A common and potentially dangerous phenomenon associated with flooding is seepage under levees and the formation of sand boils. Seepage flow due to hydrostatic head gradients of floods may cause deformation of pervious layers leading to heave, piping and sand boils. Underseepage may also cause irreversible changes in the characteristics of the porous medium. A series of independent flood events may have cumulative effects on pervious layers causing sand boils to grow. Current underseepage analyses for levees are based on steady-state flow. Transient seepage flow due to rapid changes in river head may contribute to cumulative effects and cause critical …