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The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …

Structural And Kinematic Investigation Of The Dadeville Complex-Brevard Zone Contact (Southern Appalachians): Polyphase Emplacement Of An Allochthonous Terrane On The Laurentian Margin, Andrew Williams

Master's Theses

The Dadeville Complex (DC) lies in the Inner Piedmont of eastern Alabama and western Georgia. The DC formed as a volcanic island arc during the Taconic orogeny (Ordovician Period) and was accreted onto Laurentia during the Acadian orogeny (Devonian-Mississippian Periods); however, the mechanism and role of accretion during the Acadian orogeny is not well constrained. Three proposed emplacement mechanisms for the DC include: (1) orogen-perpendicular translation; (2) orogen-parallel translation; (3) orogenic channel flow.

Today, the DC is a major (over 100 kilometers long) allochthonous terrane composed mostly of meta-igneous rocks. This study investigated structural fabrics and kinematic indicators in the …

New Insights Into The Paleovegetation Of The Ancient Underwater Forest Located In The Northern Gulf Of Mexico, Karla Lizarraga Garcia

Master's Theses

A well-preserved remnant of an ancient bald cypress forest (hereafter, Underwater Forest) constitutes the only known archive of a glacial refuge on the once exposed continental shelf of the Northern Gulf of Mexico. This forest existed around 41-72 yBP (MIS 3-5) according to the existing dating methods applied on previous studies. As the climate conditions and sea levels changed, the vegetation of this glacial refuge shifted from bald cypress forests to open marshes, altering the vegetation dynamics. The present research analyzed four new cores (21DF-5A, 21DF-5B, 15DF-6, and 16DF-3A), which provided additional insights into the vegetation that once existed in …

Hydrothermal Fluid Transport Pathways Along Fractures And Veins At Brothers Volcano, Southern Kermadec Arc, Robert Atnip

Master's Theses

Hydrothermal fluid flow in fractures and veins is a key component in the mineralization of economic metals within calderas. But there are several methods by which fractures can form. Regional extension, episodic caldera collapse, and fluid overpressure all have the potential to create brittle features. Current studies focus on the formation of fractures and veins by these methods, but do not focus on the preferred movement of hydrothermal fluids through brittle features, nor which features are more dominant in active hydrothermal systems. This thesis introduces multiple studies to better understand which method of fracture creation dominates Brothers volcano. Data from …

Benthic Habitat Mapping Of Mountain Top Bank Within The Northern Gulf Of Mexico Through Integrated Geophysical And Visual Data Analysis, Bethany Pertain

Master's Theses

Mesophotic coral ecosystems (MCEs) are among the seafloor ecosystems that have been poorly studied throughout the world’s oceans, but they are a vital and diverse ecosystem that should be prioritized for future mapping and ecological studies. Priority should be given to them because they possess natural, social, and economic values, and face a variety of threats, all of which, if not better understood will result in the loss of this unique ecosystem. Insights into these ecosystems, among other deep-sea environments, are lacking due to difficulty accessing them, inherent lag between data collection by an autonomous system and observation by a …

Melt Inclusion Record Of Submarine Caldera Formation On Axial Seamount, Juan De Fuca Ridge, Destiny Kapule

Master's Theses

This study contributes to understanding magmatic processes and the plumbing system of submarine volcanoes before, during, and after caldera formation with the use of melt inclusions (MIs). Major, trace and volatile geochemistry from both olivine and plagioclase-hosted MIs taken from volcaniclastic deposits around Axial Seamount reveal information about the storage conditions, ascent rates and eruption styles of magmas. Magma crystallizes in the subsurface, capturing MIs, and ascends where some host glasses may interact with seawater during eruption. Oversaturation in volatiles and low vesicularity show quick ascent rates. By analyzing chemical data within a pre-existing stratigraphic context this study can assess …

Structure, Construction, And Emplacement Of The Northern Margin Of The Late Cretaceous Sonora Pass Intrusive Suite: North-Central Sierra Nevada Batholith, California, Victoria A. Arnold

Master's Theses

Of the four voluminous, normally zoned Late Cretaceous intrusive suites of the Sierra Nevada batholith, the >1,000 km², ~96-88 Ma Sonora Pass intrusive suite is the oldest, northernmost, and least studied. It contains the marginal, equigranular Kinney Lakes hornblende-biotite granodiorite and the inner, porphyritic Topaz Lake biotite granodiorite. From this research, the Lake Alpine granodiorite is now considered the outermost part of the Sonora Pass intrusive suite. The suite intruded Early Cretaceous plutons and metasedimentary rocks. The Kinney Lakes and Lake Alpine granodiorites were constructed by multiple phases, as were the plutonic host rocks. The granodiorites are marked by schlieren …

Spatiotemporal Dynamics And Biogeochemical Responses In A Tidally Restricted Moro Cojo Slough, Ryan Chiu

Master's Theses

Four years of observational data for Moro Cojo Slough (MCS), a Mediterranean climate estuary in central California, linked anthropogenic nutrient loading and hydrological modifications to a shift in net ecosystem metabolism (NEM) that differs from the characteristic net heterotrophic behavior of most estuarine systems. A lack of precipitation and limited flushing during the dry seasons, as evidenced from hypersaline waters, contribute to high ecosystem respiration rates that drove NEM to nearly balanced or net autotrophic. During the wet seasons, increased runoff and nutrient loading due to precipitation elevated primary production rates within MCS, characterizing the system as net autotrophic. Box …

The Anatomy And Phylogeny Of A New Large Plioplatecarpine Mosasaur From The Campanian Bearpaw Shale Of Montana (Usa), Richard A. Carr

Master's Theses

In 2018, a large and associated plioplatecarpine mosasaur skull, pectoral girdle, and rib cage, whose total body length may have exceeded five meters, was uncovered in the Late Campanian Bearpaw Shale of Northeast Montana (USA). Phylogenetic analysis of this specimen, MOR 10855, recovers this individual as a basal member of the genus Plioplatecarpus. This specimen, is unique in that it is estimated to be nearly twice the size of any of the other species of Plioplatecarpus found in the Western Interior Seaway during this part of the Cretaceous. While the included phylogenetic study suggests MOR 10855 represents a new …

Timing Of Diversification, Dispersal, And Biogeography Of Parrots In The Genus Amazona (Psittaciformes: Psittacidae) Throughout The Caribbean, Visualized In Gis, Christopher Kingwill

Master's Theses

Avian fossil records from across the Caribbean (Greater and Lesser Antilles) demonstrate higher avian diversity prior to extinction events due to climate change at the end of the Pleistocene and human impact across the Caribbean throughout the Holocene. Amazon parrots (Amazona) are a diverse genus of New World parrots found throughout Central and South America, as well as the Caribbean. Their phylogeny and evolutionary history, specifically for Caribbean species, has been debated in terms of source areas in Central and South America and the timing of and number of colonization events to different islands that preceded diversification into …

Developing The Housing Attribute And Spatial Index (Hasi) Tool To Identify Characteristic Neighborhoods Using Variable Importance Factors Calculated Utilizing Random Forest Regression Modeling In Arcgis Pro, William A. Wallace

Master's Theses

The purpose of this research is to examine the functionality in utilizing Random Forest Regression (RFR) Variable Importance (VI) values in characterizing neighborhoods based on the attributes of existing housing units by creating an automated GIS tool. An important concept that has been implemented in the past in real-estate valuation is the concept of Hedonic Price Modeling (HPM), which uses regression techniques to identify the impacts that individual attributes have on the cost of a good in a heterogenous market outside of mere utility. The benefit of this research is to produce a tool that automates the RFR process such …

The Relationship Between Climate Social Vulnerability And Asthma, Diane Nunez

Master's Theses

Asthma is a chronic respiratory disease that affects millions of people worldwide, the incidence and severity of asthma is influenced influenced by various factors, including air masses, and weather conditions. Asthma can also disproportionately affect different sociodemographics groups, leading to inequalities and injustices. This study used statistical analysis and GIS to analyze the spatial distribution of asthma calls and their relationship to sociodemographic traits in Wichita, KS, Tulsa, OK, and Oklahoma City, OK, and the seasonal distribution of asthma calls and their relationship to air masses. Results show that the relationship between asthma prevalence is higher among certain sociodemographic groups, …