Physical Sciences and Mathematics Commons^™

Quantifying A 21-Year Surface Water And Groundwater Interaction In A Ridge And Valley Lake Environment Using A Highly Constrained Modeling Approach, Richard T. Bowers Jr.

USF Tampa Graduate Theses and Dissertations

Karst lakes are ubiquitous in ridge terrain settings in limestone aquifer coastal plain environments. In west-central Florida, these lakes are frequently connected to the Upper Floridan aquifer and have unique aquifer recharge characteristics. They have been selectively studied because they commonly have no or very limited surface water discharge and limited drainage areas, have appreciable surface water and groundwater interaction and leak to the deep aquifer. An innovative modeling approach was developed to collectively understand and more precisely quantify this vertical leakage, both from a lake-specific and regional water budget standpoint, for a 21-year study period (2000-2020). A unique, calibrated …

Volcano And Tectonic Hazard Modeling Using Interdisciplinary Geophysical And Geodetic Methods, Mitchell Scott Hastings

USF Tampa Graduate Theses and Dissertations

Volcanic and tectonic hazards such as volcanic eruptions, earthquakes and tsunamis present risks to about ~45% of the global population. They have caused at least 1.5 trillion dollars in damages worldwide since the start of the 20th century, and the costs are accelerating as population increases. In this dissertation, new data are combined with existing information and novel modeling approaches to quantify volcanic, earthquake and tsunami hazards.

The Blackfoot Reservoir Volcanic Field (BRVF) is a bimodal volcanic field on southeastern margin of the Eastern Snake River Plain in Idaho. In the BRVF, gravity anomalies reveal two shallow silicic intrusions that …

Functional Morphology And Taphonomy Of Ordovician–Silurian Diploporan Echinoderms, Stephen Ashley Hill

USF Tampa Graduate Theses and Dissertations

Diploporan echinoderms were one of the most speciose groups of stemmed echinoderms during the Ordovician. Despite this widespread abundance, the fossil record of diploporan fauna consists primarily of incomplete specimens, with complete specimens being rare. While the theca, or body, is more commonly preserved, the feeding appendages and the attachment structures (i.e. stems or holdfasts) are seldomly preserved. Insight into these features is highly valuable to the understanding the paleoecology, like the feeding and respiratory strategies, of these enigmatic creatures.

One group of diploporan echinoderms which does have an extensive fossil record, is the Holocystites Fauna, primarily known from the …

Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins

USF Tampa Graduate Theses and Dissertations

The Southwest of the United States is currently in a megadrought phase. Recent studies have shown that three of the most severe droughts of the last two millennia have occurred in the last 120 years, while geo-archaeological evidence suggests there were five megadroughts just from 150 to 950 CE. To try to better understand the causes of the droughts across the Southwest, a 110-cm long ice core was drilled from an ice deposit in a lava tube (Cave 29) from El Malpais National Monument in west-central New Mexico. The δ18O values in the ice core (ranging from −11.78 to −3.54‰) …

A Technique-Based Approach To Structure-From-Motion: Applications To Human-Coastal Environments, Robert Van Alphen

USF Tampa Graduate Theses and Dissertations

Photogrammetry is a method by which physical information can be extracted from thecorrespondence of 2-dimensional images. In the geosciences, Structure-from-Motion (SfM) photogrammetry is a technique that has seen considerable interest in the past decade of research. Here I present three case studies of various scope and methodologies which can inform the use of SfM in the geosciences. First, I discuss the theoretical and algorithmic basis of SfM photogrammetry and its uses thus far in the geosciences. Chapters two through four show specific studies which highlight several approaches to SfM and the data which can be produced. Chapter five then concludes …

Determining Depth Of Closure Based On Time-Series Beach Profiles And Empirical Formulas: A Case Study Along The Florida Coast, Elizabeth Royer

USF Tampa Graduate Theses and Dissertations

Depth of closure (DOC) is defined as the most landward depth seaward of which there is no significant change in bed elevation and no significant net sediment exchange between the nearshore and the offshore over a certain period of time, such as 5 to 20 years. DOC is an essential parameter used in beach and shore protection, sediment management, and many other aspects of coastal studies. Taking advantage of advancements in wave hindcast and bathymetry measurement in the past 20 years (2000-2019), this study determined the DOC at 12 locations along the Florida coast, including three from the northwest Gulf …

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 …

Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Isoscapes are depictions of the spatial patterns of isotopic values in a given area. Isoscapes can be created using measurements form samples (empirical isoscapes) or using statistical models of spatial isotopic variation (modeled isoscapes). Isoscapes have a wide variety of potential applications though, in the realm of marine ecology, they are most often used infer ecological processes, food web linkages, the origin of samples, and the movements of marine organisms.

However, to use isoscapes for these applications, it is necessary to have isoscapes at spatial scales relevant to the application in question. It is also necessary to have isoscapes that …

Characterizing Explosive Volcanic Eruptions Using Tephra Fall Deposit Data, Robert Constantinescu

USF Tampa Graduate Theses and Dissertations

This dissertation addresses the estimation of the magnitudes and intensities of explosive volcanic eruptions using tephra fall deposits and numerical modeling. Tephra fall deposits retain information about eruption dynamics. Volcanologists sample tephra fall deposits and measure the thickness, extent and grain size distribution to estimate the erupted volume and plume height of explosive eruptions. These terms are known as eruption source parameters. These parameters are used to classify the intensity and magnitude of the eruption on a scale such as the Volcanic Explosivity Index (VEI). Accurate estimation of the intensity and magnitude of explosive eruptions is a crucial factor in …