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Isotopic Study Of The Waters From The Sulphur Springs Catchment, Tampa, Florida, Esra Zengin

USF Tampa Graduate Theses and Dissertations

A stable isotope study was carried out using precipitation, spring water, groundwater well sample, and a seawater sample during the wet season in the Sulphur Springs watershed in Tampa, Florida. Studies that track long term isotopic variation over wet seasons are limited in the region. To fill this knowledge gap, this study aims to quantify the contributions of precipitation and diffuse sources to discharge in Sulphur Springs. A three-component mixing model was applied using δ18O and δ2H values to determine different source water contributions to spring water discharge. The three-component mixing model calculations suggest spring water consists mainly of diffuse …

Porosity And Permeability Extremes In An Eogenetic Carbonate Platform: Mechanisms For Formation And Implications For Fluid Flow, Charles I. Breithaupt

USF Tampa Graduate Theses and Dissertations

Carbonate rocks contain about a third of the worlds drinking water and host 60-70% of proven hydrocarbon reserves. Effective development and management of these resources relies heavily on geologic concepts used to predict the distribution, and magnitude of porosity and permeability in the aquifer or reservoir. Most geologic concepts used for flow prediction have been developed in telegenic limestones, where fracture networks, bedding plains, and conduits hosted in effectively impermeable bedrock control the movement of fluids, and evolution of porosity. However, a growing body of work has recognized fluid flow within eogenetic limestones is fundamentally different, and that new concepts …

Using Tidal Analysis To Examine Lake-Aquifer Connectivity On A Modern Carbonate Platform, Ronald A. Knoll

USF Tampa Graduate Theses and Dissertations

Lake-aquifer connectivity on carbonate platforms is governed by basin morphology which is influenced by diagenetic and depositional processes. Both these processes cause aquifer permeability to vary significantly with scale of measurement (i.e., pore-scale, well-scale, and regional-scale). Because coastal aquifers are well-known to have tidally controlled water level fluctuations, inland lakes may be used to expand the areal measurement of permeability and establish a link between well-scale and regional scale connectivity in the aquifer. To evaluate the impact of lake basin morphology on aquifer connectivity, water level fluctuations were collected at high temporal resolution in the ocean and twenty-four surface water …

Spatiotemporal Changes Of Microbial Community Assemblages And Functions In The Subsurface, Madison C. Davis

USF Tampa Graduate Theses and Dissertations

The subsurface hosts diverse microbial community assemblages and functions. These communities play an important role in biogeochemical cycling and groundwater purification. Many physicochemical factors affect microbial communities and can cause short-term or long-term perturbations. Subsurface microbes are susceptible to anthropogenic changes in the environment, which can be caused by nutrient inputs or municipal groundwater extraction. Despite the importance of the subsurface microbiome, these microbial communities are poorly characterized. This dissertation describes the characterization of spatiotemporal drivers of subsurface microbial communities through a variety of techniques that include eDNA analyses, bioinformatics, hydrochemical analyses, stable isotope geochemistry, and multivariate statistics. Three coastal …

3d Cave And Ice Block Morphology From Integrated Geophysical Methods: A Case Study At Scărişoara Ice Cave, Romania, Jackson Durain Hubbard

USF Tampa Graduate Theses and Dissertations

Scărişoara Ice Cave has been a catalyst of scientific intrigue and effort for over 150 years. These efforts have revealed and described countless natural phenomena – and in the process have made it one of the most studied caves in the world.

Of especial interest is the massive ice block located within its Great Hall and scientific reservations. The ice block, which is the oldest and largest known to exist in a cave, has been the focus of multiple surveying and mapping efforts, typically ones utilizing traditional equipment. In this study, the goals were to reconstruct the ice block/cave floor …

Improved 2d And 3d Resistivity Surveys Using Buried Electrodes And Optimized Arrays: The Multi-Electrode Resistivity Implant Technique (Merit), Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

This thesis presents a novel resistivity method called Multi-Electrode resistivity technique (MERIT) that is used for high resolution imaging of complex geologic features at depth and near the edges of survey lines. The MERIT electrodes are especially shaped and designed to be self-driven using a robust-direct push technique. Measurements are taken using optimized arrays that are generated using a modified version of the “Compare-R” optimization algorithm. This work focused on both two-dimensional (MERIT2D) and three-dimensional (MERIT3D) applications of the buried array and show the relevance of the additional information gained by the addition of deep electrodes especially in sites with …

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …

A Composite Spatial Model Incorporating Groundwater Vulnerability And Environmental Disturbance To Guide Land Management, Johanna L. Kovarik

USF Tampa Graduate Theses and Dissertations

Research has long recognized and studied the dynamics of groundwater processes. More recently, groundwater dependent ecosystems (GDEs) are being recognized for their diversity and vulnerability to anthropogenic impact. Groundwater in karst landscapes presents a distinctive situation where flow through the subsurface often moves rapidly on the scale of days and weeks as opposed to years or millennia in other systems. This distinctive situation of karst systems and their vulnerability to human impacts necessitate an integrated and multifaceted approach for the management of these important resources. However, development of such an approach is complicated by the difficulty of obtaining detailed data …