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Full-Text Articles in Earth Sciences

Streambed Flux Measurement Informed By Distributed Temperature Sensing Leads To A Significantly Different Characterization Of Groundwater Discharge, Troy E. Gilmore, Mason Johnson, Jesse T. Korus, Aaron R. Mittelstet, Marty A. Briggs, Vitaly A. Zlotnik, Sydney Corcoran Nov 2019

Streambed Flux Measurement Informed By Distributed Temperature Sensing Leads To A Significantly Different Characterization Of Groundwater Discharge, Troy E. Gilmore, Mason Johnson, Jesse T. Korus, Aaron R. Mittelstet, Marty A. Briggs, Vitaly A. Zlotnik, Sydney Corcoran

Conservation and Survey Division: Faculty and Staff Publications

Groundwater discharge though streambeds is often focused toward discrete zones, indicating that preliminary reconnaissance may be useful for capturing the full spectrum of groundwater discharge rates using point-scale quantitative methods. However, many direct-contact reconnaissance techniques can be time-consuming, and remote sensing (e.g., thermal infrared) typically does not penetrate the water column to locate submerged seepages. In this study, we tested whether dozens of groundwater discharge measurements made at “uninformed” (i.e., selected without knowledge on high-resolution temperature variations at the streambed) point locations along a reach would yield significantly dierent Darcy-based groundwater discharge rates when compared with “informed” measurements, focused at …


Integrating Geochronologic And Instrumental Approaches Across The Bengal Basin, Elizabeth L. Chamberlain, Steven L. Goodbred, Richard Hale, Michael S. Steckler, Jakob Willinga, Carol Wilson Nov 2019

Integrating Geochronologic And Instrumental Approaches Across The Bengal Basin, Elizabeth L. Chamberlain, Steven L. Goodbred, Richard Hale, Michael S. Steckler, Jakob Willinga, Carol Wilson

OES Faculty Publications

Constraining time is of critical importance to evaluating the rates and relative contributions of processes driving landscape change in sedimentary basins. The geomorphic character of the field setting guides the application of geochronologic or instrumental tools to this problem, because the viability of methods can be highly influenced by geomorphic attributes. For example, sediment yield and the linked potential for organic preservation may govern the usefulness of radiocarbon dating. Similarly, the rate of sediment transport from source to sink may determine the maturity and/or light exposure of mineral grains arriving in the delta and thus the feasibility of luminescence dating. …


Coupled Landscape And Channel Dynamics Across The Ganges-Brahmaputra Tidal-Fluvial Continuum, Southwest Bangladesh, Edwin Jefferson Bomer Iv Sep 2019

Coupled Landscape And Channel Dynamics Across The Ganges-Brahmaputra Tidal-Fluvial Continuum, Southwest Bangladesh, Edwin Jefferson Bomer Iv

LSU Doctoral Dissertations

The Ganges-Brahmaputra (G-B) Delta of Bangladesh and India is widely considered to be one of the most vulnerable coastal systems in the world, owing to locally-accelerated sea level rise and landscape modification by human activities. Recent research efforts have identified pronounced elevation differences between natural and embanked areas in the G-B tidal delta plain, suggesting that natural landscapes are keeping pace with sea-level rise while anthropogenic locations are actively subsiding. However, this observation represents a singular point in time, and longitudinal trends of surface elevation in these regions are presently unknown. For communities residing in upstream regions of G-B delta …


An Engineering Geological Anatomy Of The Padma River Bank Failure And Erosion, 2018: A Case Study Of Naria Bank Section, Bangladesh, Mir Fazlul Karim, Nazrul I. Khandaker, Shahidul Haque, M. Zillur Rahman, Muhammad Qumrul Hassan, Asm Maksud Kamal, Masud Ahmed, Belal A. Sayeed Sep 2019

An Engineering Geological Anatomy Of The Padma River Bank Failure And Erosion, 2018: A Case Study Of Naria Bank Section, Bangladesh, Mir Fazlul Karim, Nazrul I. Khandaker, Shahidul Haque, M. Zillur Rahman, Muhammad Qumrul Hassan, Asm Maksud Kamal, Masud Ahmed, Belal A. Sayeed

Publications and Research

The Naria town of Bangladesh is developed on the right bank of the Padma River. The bank is an old natural levee of Meghna River. The Holocene-Recent geology of Naria is actively dominated by the fluvial processes of Ganges-Brahmaputra-Meghna River system where the deltaic sediments are characterized as unconsolidated fine sand and silt, covered by thin veneer of clayey silt and loam. The annual volume of water discharge and flow dynamics are dependent on the intensity of the rainfall, runoff and the length of dry winter. Excessive river bank erosion, channel avulsion, renewed submergence of floodplains, and formation of natural …


Utilizing Dplot, Sedlog, And Arcgis Pro To Enhance Geologic Field Skills: Rosendale, Ulster County New York, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Leonardo Sanchez, Gugu Ginindza, Tyn Tyn Nai Sep 2019

Utilizing Dplot, Sedlog, And Arcgis Pro To Enhance Geologic Field Skills: Rosendale, Ulster County New York, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Leonardo Sanchez, Gugu Ginindza, Tyn Tyn Nai

Publications and Research

Capstone geologic field mapping courses in undergraduate geoscience programs aim to compliment the academic knowledge with technical field skills. As a pilot study, these tools were used to collect field data using folded lower Paleozoic to mid-Paleozoic sedimentary outcrops consisting of clastic, non-clastic and occasional mixed siliciclastics in Rosendale, Ulster County, New York. Rosendale is known for its classic geological outcrops with variable structural, stratigraphic, paleontological and sedimentological complexities – ideal for a field mapping course. Traditionally, students’ data acquisition in the field and its subsequent laboratory analysis to produce a final geologic field report utilized acetate overlays to produce …


Using Water Quality Index To Assess Groundwater Suitability At Gazipur District, Bangladesh, Muhammad Qumrul Hassan, Jowaher Raza, Mir F. Karim, Nazrul I. Khandaker Sep 2019

Using Water Quality Index To Assess Groundwater Suitability At Gazipur District, Bangladesh, Muhammad Qumrul Hassan, Jowaher Raza, Mir F. Karim, Nazrul I. Khandaker

Publications and Research

This study targeted to the suitability of groundwater for drinking purpose at Gazipur District undergoing rapid urbanization and increasing industrialization. The District has an area of 1741.53 km2, located in between 23°53' and 24°21' north latitudes and in between 90°09' and 92°39' east longitudes. From six Upazilas in Gazipur District, a total of 130 groundwater samples were collected, which are, Gazipur Sadar Upazila, Sreepur Upazila, Kaliakoir Upazila, Kapasia Upazila, and Kaligonj Upazila. A recent field observation review of industrial sludge found that heavy metal concentration was above the acceptable limit for agricultural soil. Gazipur being adjacent to Dhaka …


Positive Outcomes Of Involving Undergraduate And High School Students In Broader Aspect Of Earth System Science Through Peer Mentoring And Research Activities, Nazrul I. Khandaker, Shuayb Siddique, Matthew Khargie, Juanpablo Rodriguez, Adacia Teemal, Krishna Mahabir, Michael Robinson, Ality Aghedo, Zachary A. Sanichar, Sol De Leon, Tamzid Mubin, Elton Selby Sep 2019

Positive Outcomes Of Involving Undergraduate And High School Students In Broader Aspect Of Earth System Science Through Peer Mentoring And Research Activities, Nazrul I. Khandaker, Shuayb Siddique, Matthew Khargie, Juanpablo Rodriguez, Adacia Teemal, Krishna Mahabir, Michael Robinson, Ality Aghedo, Zachary A. Sanichar, Sol De Leon, Tamzid Mubin, Elton Selby

Publications and Research

The importance of involving undergraduates and high school students in field-and-laboratory research investigations at an early stage through peer mentoring has been clearly demonstrated as a critical tool for essential training to fully comprehend academic content and a deeper understanding of the various STEM, geoscience-and- environmental science related topics. As far as we are concerned, student presenters/participants (over 1000) in our topical sessions since 2004 have always found face-to-face presentation through poster sessions to be an ideal scientific venue where exchange of knowledge and discussion are fruitful, constructive and encouraging. It is quite revealing to note that among the student …


Barite Replacement Boxwork In The Frasassi Caves (Italy), Sandro Galdenzi Sep 2019

Barite Replacement Boxwork In The Frasassi Caves (Italy), Sandro Galdenzi

International Journal of Speleology

The Frasassi caves, located in the Sentino River Gorge in Ancona Province (Marche, Italy), contains boxwork in a small zone in the inner part of the cave system where it is closely associated with subaqueous corrosion produced by sulfuric acid speleogenesis. The boxwork consists of barite that replaces calcite spar-filled veins and limestone porosity and projects from the corroded cave walls. The replacement involved only the calcite that protrudes from the rock surfaces, indicating that the process took place in the cave environment, and therefore the boxwork is not simply a product of differential corrosion. I hypothesize that the boxwork …


Identification Of Mined Areas That May Contribute To Water Quality Degradation At Hobet Coal Mine, West Virginia, Brian P. Murphy Sep 2019

Identification Of Mined Areas That May Contribute To Water Quality Degradation At Hobet Coal Mine, West Virginia, Brian P. Murphy

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Multi-Phased Hypogene Speleogenesis In A Marginal Horst Structure Of The Malé Karpaty Mountains, Slovakia, Pavel Bella, Pavel Bosák, Petr Mikysek, Juraj Littva, Helena Hercman, Jacek Pawlak Aug 2019

Multi-Phased Hypogene Speleogenesis In A Marginal Horst Structure Of The Malé Karpaty Mountains, Slovakia, Pavel Bella, Pavel Bosák, Petr Mikysek, Juraj Littva, Helena Hercman, Jacek Pawlak

International Journal of Speleology

The Plavecká jaskyňa Cave on the western fault edge of the Malé Karpaty Mountains (western Slovakia) is a result of multi-phased hypogene speleogenesis. It formed in fractured Triassic carbonates by waters ascending along the Vienna Basin Transform Fault between Malé Karpaty Mountains and Záhorská nížina Lowland (the north-eastern part of the Vienna Basin) and/or the N–S-trending faults that intersect it in the cave vicinity. Morphologically, the cave is featured by (1) phreatic chimneys, cupolas, ceiling pockets, enlarged fissures with spongework cavities, upward wall channels and upward oriented large scallops, (2) epiphreatic flat corrosion bedrock floors, feeding fissures and wall water-table …


Reconstructing A Centennial-Scale Extreme Paleoflood History Of The Pee Dee River Using Oxbow Lake Sediments, Nicholas William Conway Aug 2019

Reconstructing A Centennial-Scale Extreme Paleoflood History Of The Pee Dee River Using Oxbow Lake Sediments, Nicholas William Conway

Electronic Theses and Dissertations

Extreme river floods are the key force shaping floodplain landscape and a major process delivering sediment, pollutants, and nutrients to coasts. These devastating natural hazards pose concerns about potential change of extreme flood occurrence in the face of climate change. However, accurately assessing the impact of anthropogenic climate change and natural climate modes on the intensity and frequency of extreme flooding relies on multi-century discharge records. Unfortunately, instrumental records are relatively short (often <100 years) and overlap with times of dam and reservoir construction. Oxbow lakes, ubiquitous in the floodplains of alluvial rivers, may preserve an archive of extreme flood at centennial timescales as they capture coarser channel sediments transported by intensified river flows. This study has identified signals of extreme floods in oxbow lake sediments and established a timeline of past flooding events to evaluate change(s) in flood hazard near the Pee Dee River (PDR), South Carolina. Laser diffraction grain-size analysis and X-ray computed tomography (CT) scanning were performed on a ~2-m long piston core (SBL2) to identify event layers of extreme floods. CT images reveal high-density laminations and corresponding coarser shifts of grain size are interpreted as flood layers. A robust age-depth model was established for SBL2 using multiple independent age controls (C14, optically stimulated luminescence, Pb210/C137, and historical event tie-points). End-member modelling analysis was performed to identify a coarse component of the grain-size data used as a proxy of extreme flood. A linear relationship between end-member modelling results and measured discharge was established for the last 80 years and applied to the older part of the core yielding peak discharge estimates back to ca. AD 1840. This analysis identifies abrupt shifts in grain size resulting from dam construction, droughts, and local geomorphic changes to the river system. A multidecadal trend in the frequency of extreme floods is present in the PDR system, controlled by Pacific Decadal Oscillation. The most extreme peak annual discharges of the PDR occurred between AD 1870-1900 from the combined interaction of increased tropical cyclone activity with intensified land use for agricultural purposes. Peak annual discharges of the PDR seem to have decreased through time since flood control damming was completed in AD 1962.


The Importance Of Landscape Position Information And Elevation Uncertainty For Barrier Island Habitat Mapping And Modeling, Nicholas Matthew Enwright Aug 2019

The Importance Of Landscape Position Information And Elevation Uncertainty For Barrier Island Habitat Mapping And Modeling, Nicholas Matthew Enwright

LSU Doctoral Dissertations

Barrier islands provide important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism. As a result, natural resource managers are concerned with monitoring changes to these islands and modeling future states of these environments. Landscape position, such as elevation and distance from shore, influences habitat coverage on barrier islands by regulating exposure to abiotic factors, including waves, tides, and salt spray. Geographers commonly use aerial topographic lidar data for extracting landscape position information. However, researchers rarely consider lidar elevation uncertainty when using automated processes for extracting elevation-dependent habitats from lidar data. …


Historical Floodplain Sedimentation Rates Using Mining Contaminant Profiles, Cesium-137, And Sediment Source Indicators Along The Lower Big River, Jefferson County, Missouri, Miranda M. Jordan Aug 2019

Historical Floodplain Sedimentation Rates Using Mining Contaminant Profiles, Cesium-137, And Sediment Source Indicators Along The Lower Big River, Jefferson County, Missouri, Miranda M. Jordan

Graduate Theses/Dissertations

Floodplain sedimentology and geochemistry can indicate the age of sediment layers to evaluate the history of human-caused sedimentation in a watershed. While the Ozark Highlands of Missouri has had a long history of settlement and land disturbance beginning in the early 1800s, there are few studies that have investigated the effects of these anthropogenic activities on river form and legacy sedimentation. The goal of this study is to characterize the sediment properties and geochemical trends in post-settlement floodplain deposits along lower Big River in Jefferson County, Missouri. This study evaluated trends of sediment properties at 3 cm intervals in a …


Stream Channel Morphology And Riparian Forest Response To A 500-Year Flood In The Missouri Ozarks, Joshua William Hess Aug 2019

Stream Channel Morphology And Riparian Forest Response To A 500-Year Flood In The Missouri Ozarks, Joshua William Hess

Graduate Theses/Dissertations

Climate change has increased the frequency of large floods in rivers draining the Ozark Highlands resulting in higher rates of channel sedimentation, bank erosion, and damage to infrastructure. This study assesses the effects of a large flood (>500-year RI) during April-May 2017 on riparian forests along six tributary streams in the North Fork of the White River watershed, Missouri. High-resolution (<8 >cm) Unmanned Aerial Vehicle (UAV) imagery collected after the flood was used to identify riparian forest flood damage. Measurements of riparian forest flood damage calculated from the UAV imagery were verified through field surveys of damaged riparian trees. …


Geomorphic And Land Use Controls On Headwater Channel Morphology In Mark Twain National Forest, Grace F. Roman Aug 2019

Geomorphic And Land Use Controls On Headwater Channel Morphology In Mark Twain National Forest, Grace F. Roman

Graduate Theses/Dissertations

Prescribed burning has been used over the past two decades to manage forests and restore shortleaf pine-oak woodlands in Mark Twain National Forest (MTNF). While soil studies have been completed, no assessments of burning practices on small drainage channel systems have yet been done. Headwater streams may account for more than two-thirds of total stream length and are important to the maintenance of hydrologic connectivity in watersheds. This study’s focus is on understanding the relationship between frequency of forest burning and channel morphology (size, shape, and substrate) of headwater streams (km2). A combination of field measurements, geo-processing methods, …


The Structure And Dynamics Of A River Delta Are Related Through Its Nourishment Area, Suggesting Optimality, Christopher A. Cathcart Aug 2019

The Structure And Dynamics Of A River Delta Are Related Through Its Nourishment Area, Suggesting Optimality, Christopher A. Cathcart

Graduate Theses and Dissertations

Scaling relations in tributary network geomorphology are well understood with respect to optimality. However, the scaling relations between structure and dynamics in distributary network geomorphology are less well understood. This is primarily due to the fact that nourishment area boundaries are difficult to map compared to tributary network catchment area boundaries. Furthermore, most previous work has focused either on the distributary channel networks or the delta’s partitioning of discharge. Here we show that, on the Wax Lake Delta (WLD) in Louisiana, the asymmetry in nourishment areas and downstream nourishment boundary width (∏) at a channel bifurcation, acts as a control …


Historical Land Use Influence On Fine-Grained Sedimentation In Channel And Floodplain Deposits In A Forested Missouri Ozark Watershed, Katy Nicole Reminga Aug 2019

Historical Land Use Influence On Fine-Grained Sedimentation In Channel And Floodplain Deposits In A Forested Missouri Ozark Watershed, Katy Nicole Reminga

Graduate Theses/Dissertations

Hydrologic disturbances due to land use and climate effects can disrupt river form and increase sediment transport. Ozark streams have been experiencing the effects of accelerated channel erosion on coarse sediment delivery and gravel bar deposition since the onset of early European settlement in the late 1800’s. Little attention has focused on understanding the fate of fine-grained sediment released by upland soil and headwater channel erosion and the potential for storage as legacy deposits on floodplains. Legacy deposits are attributed to human disturbances as the result of land clearing and agriculture that increase runoff, soil erosion, flooding, and sediment supply …


Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion Aug 2019

Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion

Master's Theses

Horn and Petit Bois islands are two of five Mississippi (MS) barrier islands that provide physical protection from tropical cyclones threatening the MS Gulf Coast, in addition to critical habitat for the northern Gulf of Mexico (GOM). In September 2004, Hurricane Ivan removed a large volume of sediment from the eastern ends of Horn and Petit Bois islands with its 1-2 m storm surge and ~194 kph wind speeds. Then, in August 2005 Hurricane Katrina severely impacted the two islands again with its 3.5-5.5 m storm surge on Horn and Petit Bois islands, and up to 204 kph wind speeds …


Lidar-Based Sinkhole Detection And Mapping In Knox County, Tennessee, J Clint Shannon, David Moore, Yingkui Li, Cathy Olsen Jul 2019

Lidar-Based Sinkhole Detection And Mapping In Knox County, Tennessee, J Clint Shannon, David Moore, Yingkui Li, Cathy Olsen

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Sinkholes are one of the major causes of damage to roads, buildings, and other infrastructure throughout the US. Sinkholes near or on roads are especially costly and occasionally deadly. Knox County and much of East Tennessee are located within karst areas (comprised of porous and soluble limestone and dolomite), deeming it at risk for sinkholes. Currently, Knox County uses contour maps to manually identify sinkholes. Supported by a geographic information system (GIS), we developed a streamlined model to identify the locations and extents of potential sinkholes using 1.3-ft resolution LiDAR (Light Detection and Ranging) data and applied it to the …


Identifying Characteristics Of Actionable Science For Drought Planning And Adaptation, Adam Wilke, Amanda Cravens Jul 2019

Identifying Characteristics Of Actionable Science For Drought Planning And Adaptation, Adam Wilke, Amanda Cravens

United States Geological Survey: Publications

Changing climate conditions can make water management planning and drought preparedness decisions more complicated than ever before. Federal and State natural resource managers can no longer rely solely on historical trends as a baseline and thus are in need of science that is relevant to their specific needs to inform important planning decisions. Questions remain, however, regarding the most effective and efficient methods for extending scientific knowledge and products into management and decision-making. This project analyzed two unique cases of water management to better understand how science can be translated into resource management actions and decision-making, focusing particularly on how …


Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne Jul 2019

Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne

International Journal of Speleology

An iron cave in the vicinity of a mine in Carajás, Brazil, was selected to be mined within an assisted elimination project, planned to control all mine advancement operations towards the cave along with a strict speleological physical monitoring. It allowed, in a pioneering way, the recording of events in the cave from the first signs of damage until to the total collapse of the cave. The project lasted four years and it was possible to identify and describe four breakdown mechanisms in iron caves: Fragment downfall, Block downfall, Controlling structure reactivation, and Open discontinuity movement. The mechanisms occurred independently …


Gage County Preliminary Ground Water Study (Gm-20): Reed, E.C. Conservation And Survey Division , Size 8.5" X 11"., E.C. Reed Jul 2019

Gage County Preliminary Ground Water Study (Gm-20): Reed, E.C. Conservation And Survey Division , Size 8.5" X 11"., E.C. Reed

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Tourism Impact Index For Water-Based Natural Attractions Field-Tested In Subarctic And Maritime Climates, Jason Fox Jul 2019

A Tourism Impact Index For Water-Based Natural Attractions Field-Tested In Subarctic And Maritime Climates, Jason Fox

Masters Theses & Specialist Projects

Tourism in cold and cool-climate regions is largely characterized by recreational and sightseeing activities at water-based natural attractions such as beaches, coastal cliffs, and waterfalls. While the economic benefits of the tourism industry can contribute to a sustainable future for these regions, the environmental implications of a hastilydeveloped industry cannot be ignored given that cold-climate and cool-climate landscapes are at risk of rapid environmental change from a warming climate and other environmental concerns. This study consisted of the development of the Tourism Impact Index for Water-Based Natural Sites, the first of its kind, and its application and refinement in the …


Distributary Channel Networks As Moving Boundaries: Causes And Morphodynamic Effects, Robert C. Mahon, John B. Shaw, Wun-Tao Ke, Christopher A. Cathcart Jul 2019

Distributary Channel Networks As Moving Boundaries: Causes And Morphodynamic Effects, Robert C. Mahon, John B. Shaw, Wun-Tao Ke, Christopher A. Cathcart

Earth and Environmental Sciences Faculty Publications

We propose an exploratory model to describe the morphodynamics of distributary channel network growth on river deltas. The interface between deep channels and the shallow, unchannelized delta front deposits is modeled as a moving boundary. Steady flow over the unchannelized delta front is friction dominated and modeled by Laplace's equation. Shear stress along the network boundary produces nonlinear erosion rates at the interface, causing the boundary to move and network elements (channels and branches) to form. The model was run for boundary conditions resembling the Wax Lake Delta in coastal Louisiana, 20 parameterizations of sediment transport, and 3 …


Structural Control Of Mesic Vegetation Communities Within The Owl And Bear Creek Watersheds, Fort Hood Military Installation, Texas, Melinda S. Faulkner, Matthew Mcbroom, Kenneth W. Farrish, Kevin Stafford Jun 2019

Structural Control Of Mesic Vegetation Communities Within The Owl And Bear Creek Watersheds, Fort Hood Military Installation, Texas, Melinda S. Faulkner, Matthew Mcbroom, Kenneth W. Farrish, Kevin Stafford

Faculty Publications

The Fort Hood Military Installation is a karst landscape, dominated by Lower Cretaceous carbonates of the Trinity and Fredericksburg groups. The study area is the northeastern peninsula known as the Owl Mountain Province, utilized by the U.S. Army for troop maneuvers and training. The geomorphic evolution of the province has been controlled by the structural development of incised canyons in the Owl and Bear creek watersheds, following the deformational trend of the Balcones/Ouachita fault system and the transverse Belton High-Central Texas Reef Trend. These trends control cave development in the subsurface, karst manifestations at the surface, joints in outcrop, stream …


Understanding The Relationship Between Sedimentation, Vegetation And Topography In The Tijuana River Estuary, San Diego, Ca., Darbi Berry May 2019

Understanding The Relationship Between Sedimentation, Vegetation And Topography In The Tijuana River Estuary, San Diego, Ca., Darbi Berry

Theses

The aim of this study is to identify and characterize key geomorphic properties and relationships within the study site, the Tijuana River Estuary. This is a first step in contributing data to and assisting current and future restoration projects in employing a holistic management approach. The study identifies specific physical parameters, grain size and metal concentrations, within the estuary whose relationship to one another is not mutually exclusive and therefore should be addressed in tandem. This study also tests a remote sensing method for use as a tool for monitoring habitat changes in the estuary.


Geomorphic And Temporal Evolution Of A Mississippi Delta Flanking Barrier Island: Grand Isle, La, Julie A. Torres May 2019

Geomorphic And Temporal Evolution Of A Mississippi Delta Flanking Barrier Island: Grand Isle, La, Julie A. Torres

LSU New Orleans Theses and Dissertations

Optically stimulated luminescence (OSL) dating beach ridge sediments is one method for resolving barrier island growth at intermediate scales (decades-centuries), information that is lacking for Louisiana. This research combines OSL, GPR, aerial imagery, and cores to document temporal and spatial evolution of a Louisiana barrier island.

Grand Isle is composed of beach ridges organized in distinct, unconformable sets that began forming 0.75 ka until 0.575 ka when deposition ceased, the ridges were partially eroded, and deposition resumed in a more eastward direction. The central ridges formed between 370±30 and 170±10 years ago at a rate of one ridge every 11.6 …


Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock May 2019

Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock

LSU New Orleans Theses and Dissertations

Light Detection and Ranging (Lidar) data are used to report the temporal and spatial patterns of subsidence as well as the potential contributors to subsidence within the Barataria and Terrebonne Bays. In recent decades, subsidence in southeast Louisiana has become a topic of substantial and growing concern to the scientific community, the local residents, and all those invested in the region. Lidar data were acquired from the United States Geological Survey (USGS) and the LSU Center for Geoinformatics. The data has been manipulated to map the differenced Lidar, complete an instantaneous slope analysis, and determine the thickness of the Holocene …


Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh May 2019

Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh

LSU New Orleans Theses and Dissertations

An in-depth field study of the Delacroix Island producing field illustrates the evolution of the east-trending Delacroix Island Fault during the last 13 My. Well log correlations and 3-D seismic interpretation of 22 subsurface bio-stratigraphic horizons across the fault reveal variable stratigraphic thicknesses and displacement. Wells, with well log curve data as shallow as 31 m (100 ft) below the surface, were used to calculate interval thicknesses, expansion indices, sediment accumulation rates, burial history and magnitudes of displacement. Through these analyses, a correlation was found between the positioning of ancient Miocene depocenters over Delacroix Island and a period of increased …


Geomorphic Response To Catastrophic Flooding In A Karst Mountain Stream System, Brighton-Blue Hole Watershed, Southwest Jamaica, Sarah M. Letarte May 2019

Geomorphic Response To Catastrophic Flooding In A Karst Mountain Stream System, Brighton-Blue Hole Watershed, Southwest Jamaica, Sarah M. Letarte

Graduate Theses/Dissertations

The geomorphic effects of flooding are poorly understood in the karst, mountain watersheds along the southwest coast of Jamaica. This study describes the flow path and geomorphic response of an extreme flood event in the Brighton-Blue Hole watershed (BBHW) (6.8 km2) near Belmont, Westmoreland, Jamaica. A tropical depression classified as a >100-year rainfall event produced 32 inches of rain in a 24 hour period in Westmoreland on June 12, 1979. For this study, geomorphic indicators of flood disturbance in BBHW were assessed in 2017-18, finding that channel system responded to the flood with channel incision, debris flows, and …