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Investigation Of Subsurface Stratigraphy And Groundwater Dynamics In The Mississippi River Delta, An Li

LSU Doctoral Dissertations

The Mississippi River Delta (MRD) is socioeconomically important to the state of Louisiana and the United States. Various types of land-water system data have been collected in the MRD. However, very few efforts have been made to utilize these datasets in modeling regional stratigraphy and groundwater dynamics in the MRD, especially for the upper 50 m of the depth. In this interval of depth, the Mississippi River and surrounding interdistributary bays intensively interact with the groundwater system. The lack of knowledge in regional stratigraphy and groundwater dynamics hinder an understanding of how hydrogeological setting affects processes such as surface-groundwater interaction, …

Deep Open Storage And Shallow Closed Transport System For A Continental Flood Basalt Sequence Revealed With Magma Chamber Simulator, Jussi S. Heinonen, Arto V. Luttinen, Frank J. Spera, Wendy A. Bohrson

All Faculty Scholarship for the College of the Sciences

The Magma Chamber Simulator (MCS) quantitatively models the phase equilibria, mineral chemistry, major and trace elements, and radiogenic isotopes in a multicomponent–multiphase magma + wallrock + recharge system by minimization or maximization of the appropriate thermodynamic potential for the given process. In this study, we utilize MCS to decipher the differentiation history of a continental flood basalt sequence from the Antarctic portion of the ~ 180 Ma Karoo large igneous province. Typical of many flood basalts, this suite exhibits geochemical evidence (e.g., negative initial εNd) of interaction with crustal materials. We show that isobaric assimilation-fractional crystallization models fail to …

Reconstructing Coastal Sediment Budgets From Beach- And Foredune-Ridge Morphology: A Coupled Field And Modeling Approach, Daniel J. Ciarletta, Justin L. Shawler, Christopher Tenebruso, Christopher J. Hein, Jorge Lorenzo Trueba

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Preserved beach and foredune ridges may serve as proxies for coastal change, reflecting alterations in sea level, wave energy, or past sediment fluxes. In particular, time-varying shoreface sediment budgets have been inferred from the relative size of foredune ridges through application of radiocarbon and optically stimulated luminescence dating to these systems over the last decades. However, geochronological control requires extensive field investigation and analysis. Purely field-based studies might also overlook relationships between the mechanics of sediment delivery to the shoreface and foredune ridges, missing insights about sensitivity to changes in sediment budget. We therefore propose a simple geomorphic model of …

Reconstructing Coastal Sediment Budgets From Beach‐ And Foredune‐Ridge Morphology: A Coupled Field And Modeling Approach, Dj Ciarletta, Jl Shawler, C Tenebruso, Christopher J. Hein, J Lorenzo‐Trueba

VIMS Articles

Preserved beach and foredune ridges may serve as proxies for coastal change, reflecting alterations in sea level, wave energy, or past sediment fluxes. In particular, time‐varying shoreface sediment budgets have been inferred from the relative size of foredune ridges through application of radiocarbon and optically stimulated luminescence dating to these systems over the last decades. However, geochronological control requires extensive field investigation and analysis. Purely field‐based studies might also overlook relationships between the mechanics of sediment delivery to the shoreface and foredune ridges, missing insights about sensitivity to changes in sediment budget. We therefore propose a simple geomorphic model of …

Reconstructing Barrier Island Behavior From Overstepped Deposits And Relict Onshore Morphology : Modeling And Field Approaches, Daniel James Ciarletta

Theses, Dissertations and Culminating Projects

Barrier Islands comprise 10% of the Earth’s shorelines, fringing every continent except Antarctica. Despite their ubiquity, much about the medium to long-term evolution of these coastal systems remain poorly understood, mostly due to the destruction of the geologic record as barriers migrate landward under the influence of rising sea level. Even where modern barriers and related strandplain systems have prograded and regressed, leaving evidence of their former geometries in the form of relict shorelines, field investigations often require intensive labor and time commitments to interpret past evolution. In this work, several investigations are undertaken to use novel numerical modeling techniques …

Capture Zone Analysis Of A Wellfield To Assess Contaminant Transport, Prince Kojo Oware

Theses and Dissertations

Radium is a common contaminant to the deep Cambrian- Ordovician aquifer in northern Illinois. Deep groundwater aquifers are used as fresh water resource in many parts of the world. Due to overuse, increase in salinity, natural and human-driven contamination, sustainability of these aquifer systems is uncertain. The purpose of this study is to better understand the groundwater flow system in deep bedrock aquifers in northern Illinois, and its control on the radium contamination in Rochelle’s Public Water Supply Wells (PWSW). We have tested two hypotheses: (1) the Radium (Ra) transport is driven by large pumping centers that interrupt groundwater flow …

Thermal Maturation Modeling Of The Michigan Basin, Jack H. Hybza

Masters Theses

Given present day heat flow and burial depths in the Michigan Basin, hydrocarbons should be immature. However, oil and gas are abundant within the basin. Our hypothesis is that thermal maturation distributions in the Michigan Basin can be explained by variations in proximity to the Midcontinent Rift (MCR) system, thermal cooling, crustal convection, high temperature fluid advection, and eroded overburden.

For each of the seven wells in this study, a geohistory plot is coupled with a range of geodynamic models to calculate the thermal and maturation histories of each sediment unit within the well. Backstripping was used to generate basement …

Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri

USF Tampa Graduate Theses and Dissertations

Maintenance of aging buried infrastructure and reinforced concrete are critical issues in the United States. Inexpensive non-destructive techniques for mapping and imaging infrastructure and defects are an integral component of maintenance. Ground penetrating radar (GPR) is a widely-used non-destructive tool for locating buried infrastructure and for imaging rebar and other features of interest to civil engineers. Conventional acquisition and interpretation of GPR profiles is based on the arrival times of strong reflected/diffracted returns, and qualitative interpretation of return amplitudes. Features are thereby generally well located, but their material properties are only qualitatively assessed. For example, in the typical imaging of …

Geophysical Analysis Of The Midcontinent Rift’S Subsurface Structure In Southeastern Nebraska, Patrick Szopinski

Honors Theses

The Midcontinent Rift System (MCRS) is a 1.1 billion-year-old failed rift system that spans much of the North American continental interior. The MCRS is exposed at Lake Superior and is buried in the subsurface along its southwest-extending arm through southeastern Nebraska. Due to the presence of buried volcanic rocks, the MCRS has characteristic highly-pronounced potential field anomalies (gravity and magnetic). Despite these large anomalies, not much is known about the subsurface faulting associated with the rift zone in the Midwest. The goal of this project is to attempt to use integrated analysis of collected geophysical data from multiple methods to …

Ice Flow Impacts The Firn Structure Of Greenland's Percolation Zone, Rosemary C. Leone

Graduate Student Theses, Dissertations, & Professional Papers

One dimensional simulations of firn evolution neglect horizontal transport as the firn column moves down slope during burial. This approach is justifiable near Greenland's ice divide, where ice flow is near vertical, but fidelity is lost in the percolation zone where horizontal ice flow advects the firn column through climate gradients. We simulate firn evolution processes under advection conditions using a transient, thermo-mechanically coupled model for firn densification and heat transfer with various schemes for meltwater penetration and refreezing. The simulations isolate processes in synthetic runs and investigate an ice core site and four transects of Greenland’s percolation zone. The …