Physical Sciences and Mathematics Commons^™

Behavior Of Rare Earth Elements And High-Field Strength Elements During Peridotite - Seawater Interaction, Carl Pasquale Frisby

Theses and Dissertations

Serpentinized abyssal peridotites are evidence for active communication between the Earth’s hydrosphere and the upper mantle, where exchange and retention of both major and trace elements occur. Rare earth elements (REE) and high-field strength elements (HFSE: Ti, Zr, Hf, Nb, Ta) are generally thought of as immobile during serpentinization. In partially serpentinized abyssal peridotites, clinopyroxenes typically retain radiogenic Nd and Hf isotopic signatures that have been used to infer the composition and high temperature processes in the upper mantle. However, bulk rock Nd isotopes in some serpentinized abyssal peridotites less radiogenic values that approach that of seawater, which has been …

From Near And Far: Utilization Of In-Situ And Remotely Sensed Satellite Data From Nasa And Noaa, Jessica Rochelle Price Sutton

Theses and Dissertations

Satellite remote sensing observations have been used for numerous studies to better understand physical and biological properties over varying spatial and temporal scales. Depending on the satellite and sensor, the satellite-derived observations can provide high spatial and temporal resolution for many important physical and biological variables. While there are many limitations in utilizing satellite remote sensing products, there are also many advantages. This dissertation investigates three different applications for satellite remote sensing products to address climatological and ecological concerns. This dissertation is motivated by two overall research questions: (1) How can satellite remote sensing products be used to address important …

Platinum Decoupling From Pge In Peridotitic Sulfides From The St. Elena Ophiolite In Costa Rica, Jessica A. Holm

Theses and Dissertations

The platinum group elements (Os, Ir, Ru, Rh, Pt, Pd) are important petrogenetic tracers of mantle processes and the Re-Os isotope system an important tool for tracing ancient depletion and refertilization processes in the mantle. A key characteristic of these elements is that they are siderophile and chalcophile, and their abundance in the Earth’s mantle is thought to be controlled by sulfides. Existing thermodynamic data suggests that at reducing conditions similar to those found at the early stages of serpentinization, PGE may exist as alloys in the mantle. While numerous studies report on the bulk peridotite PGE and sulfide PGE …

Small Mud And Sand Filled Paleochannels Offshore Charleston, Sc, Erin Smoak

Theses and Dissertations

The spatial variations of Quaternary sediments on the continental shelf record the progression of depositional environments during the latest sea-level rise, and are fundamental controls on submarine groundwater discharge (SGD) flow. SGD on continental shelves is an important but poorly constrained process. Spatial variations of lithologies on continental shelves, such as sand-filled paleochannels, are assumed to play a fundamental role in controlling where SGD occurs but coincident seismic mapping and sedimentological data are rare. Here we combine seismic mapping of paleochannel locations with sediment cores to examine the sedimentary characteristics of paleochannel fill and interfluvial deposits. To establish paleochannel locations …

Ecohydrology And Groundwater Dynamics In A Salt Marsh Island, Andrea L. H. Hughes

Theses and Dissertations

Tidal salt marshes are extraordinarily productive and valuable ecosystems that provide via groundwater a not insignificant portion of coastal solute and nutrient budgets. Among the many goods and services they provide are habitat for diverse wildlife, protection for coastal communities during storms, and protection for coastal surface waters by filtering anthropogenic pollutants. One threat to the health of tidal salt marshes along the East Coast have been episodes of Acute Marsh Dieback (AMD) from 1999 to 2001. Dieback was observed at North Inlet salt marsh from 2000 to 2001. Since salt marsh hydrology is dominated by the local tidal regime, …

An Integrated Structural Analysis On Seismic Of A Paleo Mound Development (Woolsey Mound, Northern Gulf Of Mexico), Ricardo Tomas Troco Kabila

Theses and Dissertations

Woolsey Mound is ~1 km diameter thermogenic gas hydrate and cold seep (GHCS) complex system. It is located at ~900 m water depth in the Mississippi Canyon Lease Block 118 (MC–118) on the upper continental slope of the northern Gulf of Mexico (GOM). Due to its complex geology, widespread hydrate seepage activity and presence of benthic habitat, the mound serves as a permanent research site for a multidisciplinary seafloor observatory, thus providing insights into the dynamics of shallow fluid expulsion, their spatial and time variations and possible geological forcing mechanisms.

This study utilizes a set of high resolution 2D autonomous …

Alongshore Momentum Balance Over Shoreface-Connected Ridges, Fire Island, Ny, Conor Ofsthun

Theses and Dissertations

Bathymetric variations, such as shoreface-connected ridges (SFCRs), modify inner shelf circulation, altering the significance of and relationships between alongshore momentum balance terms. The inner shelf of Fire Island, NY provides a study site representative of SFCRs around the world. During the winter of 2014, hydrodynamic observations (~12 m depth) from 6 ADCPs, 3 SeaGauge pressure sensors, 2 tide gauges, and 2 meteorological buoys were collected over a region of the inner shelf spanning a full wavelength of one such SFCR. Analysis of the data, under westward wind forcing, revealed a predominantly alongshore circulation with localized offshore (onshore) current veering over …

Utilization Of Satellite-Derived Salinity For Enso Studies And Climate Indices, Caroline Mary Corbett

Theses and Dissertations

Conventionally, El Niño-Southern Oscillation (ENSO) is studied using sea surface temperature (SST) observations in the central and eastern equatorial Pacific Ocean. Recently, sea surface salinity (SSS) in the equatorial Pacific has been studied in relation to the phases of ENSO. Previously, SSS was observed in the equatorial Pacific using the Tropical Ocean Global Atmosphere (TOGA) / Tropical Atmosphere Ocean (TOA), the Argo float network, and Oceanic General Circulation Models (OGCM). The launch of NASA’s Aquarius Salinity Mission and ESA’s Soil Moisture Ocean Salinity (SMOS) opened a new era in which high resolution global near real-time SSS observations are readily available. …

Neuro-Fuzzy Classification Of Felsic Lava Geomorphology At Alarcon Rise, Mexico, Christina Hefron Maschmeyer

Theses and Dissertations

The Alarcon Rise is the only submarine oceanic spreading ridge setting where rhyolitic lavas have been found. This intermediate-rate spreading ridge provides a unique natural laboratory for studying the geomorphology of felsic submarine lava flows at oceanic spreading ridges. Seafloor observations of felsic lava indicate the flow morphology differs from typical submarine basaltic lava at the few other oceanic spreading ridges where differentiated compositions have been recorded. Morphologic variation between mafic and felsic lava flows, especially rhyolites, was also observed at Alarcon Rise.

The Monterey Bay Aquarium Research Institute conducted mapping surveys with autonomous underwater vehicle D Allan B. in …

Submarine Groundwater Discharge And The Configuration Of The Freshwater-Saltwater Interface At The Nearshore And Embayment Scales, Tyler Brandon Evans

Theses and Dissertations

Submarine groundwater discharge (SGD) rivals riverine discharge to the world’s oceans but remains poorly understood. Until the early 1990’s, geochemical budgets for the ocean were developed using material fluxes from rivers only. SGD has been shown to carry high concentrations of dissolved nutrients, metals and carbon. However, SGD is a difficult to measure, complex phenomenon driven by multiple physical processes. Groundwater flow and the resultant chemical exchange at the land-sea interface are heavily impacted by the hydrodynamic effects of mixing between variable-density fluids. In order to better understand SGD, investigations have focused on the configuration of the freshwater-saltwater interface in …

Three Dimensional Thermobaric Modeling Of A Gas Hydrate System, Amanda Quigley Williams

Theses and Dissertations

Seismic imaging is recognized as the most cost effective method for identifying the presence of gas hydrate resources. The base of the gas hydrate stability zone is recognized by the presence of regionally extensive bottom simulating reflectors (BSR). However, in some areas such as the Gulf of Mexico, regionally extensive BSRs are not found. In such cases, an understanding of the thermobaric conditions may be used to determine the location of gas hydrates and the base of the gas hydrate stability zone. The aim of this research is to combine seismic velocity analysis and thermal modeling to predict the base …

3d Seismic Depth Imaging And Velocity Model Building In Anisotropic Media: Serri Oil And Gas Field, Saudi Arabia, Ali Jomaah Alsalem

Theses and Dissertations

Seismic imaging is a significant element in hydrocarbon exploration to locate drilling prospects and it relies mainly on an accurate velocity model. Prestack depth migration (PreSDM) versus traditional post-stack time migration has become a common method for seismic velocity model building and imaging. This methodology accounts for seismic velocity anisotropy of the propagating waves in the subsurface with a higher level of accuracy in positioning the seismic events in their true positions in the subsurface.

In this thesis, we examine a 303 km2 of 3D seismic data acquired by Saudi Aramco in the Serri field of North-West Saudi Arabia. The …

Implications Of Hf-Nd Isotopes In West Philippine Basin Basalts For The Initiation And Early History Of The Izu-Bonin-Mariana Arc, Benjamin D. Hocking

Theses and Dissertations

Drilling at Site U1438, located immediately west of Kyushu-Palau Ridge (KPR), the site of IBM subduction initiation, penetrated 1,460 m of volcaniclastic sedimentary rock and 150 m of underlying basement. Biostratigraphic controls indicate a probable age for the oldest sedimentary rocks at around 55 Ma. This is close to the 48-52 Ma time period of IBM subduction initiation, based on studies in the forearc. There, the first products of volcanism are tholeiitic basalts termed FAB (forearc basalt), which are more depleted than average MORB and show subtle indicators of geochemical enrichment due to subduction. Site U1438 basement basalts share many …

Delineation Of The Lower Permian Gas Sand Via Calibrated Avo And Pre-Stack Seismic Inversions In Majhol Field, Saudi Arabia, Abdullah Alhashel

Theses and Dissertations

The lower Permian formation in the central region of Saudi Arabia is a key hydrocarbon siliciclastic reservoir. However, in Majhol field, the reservoir properties vary laterally due to diagenesis and facies changes. Conventional seismic interpretation has failed to map the heterogeneities of the reservoir properties that control the gas production of this field. Therefore, there was an opportunity to employ more advanced quantitative seismic techniques to delineate the productive gas sand facies in the field.

The Majhol field was initially planned to be developed as an unconventional tight reservoir. Well-1 was drilled based on conventional seismic interpretation on the crest …