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Seismic-stratigraphic analysis of shelf-margin delta/slope fan and basin floor fan on high-latitude and middle-latitude margins (Ross Sea, Weddell Sea and Alabama/West Florida shelf): Paleoclimatic and eustatic implications
This dissertation consists of three chapters describing seismic stratigraphic studies in three very different continental margin settings. The first chapter discusses the northwestern Ross Sea, the second discusses the southeastern Weddell Sea and the third discusses the Alabama/west Florida margin. The purpose was to investigate stratigraphic ...
Marine geology of the northwestern Weddell Sea and adjacent coastal fjords and bays: implications for glacial history
Sedimentologic, compositional, and cleat shape analyses reveal that piston cores obtained on the northwest Weddell See continental shelf penetrated residual glacial marine sediments adjacent to Seymour Island, compound glacial marine sediments north of 64
Sedimentological Investigations of Paleo-Ice Sheet Dynamics in West Antarctica
Modern Pine Island and Thwaites Glaciers, which both drain into Pine Island Bay, are some of the fastest moving portions of the cryosphere and may be the most unstable ice streams in Antarctica. I examined over 133 cores to conduct a detailed sedimentological facies analysis. These data, augmented by new radiocarbon and 210Pb dates, and bathymetric ...
The evolution of the Brazos and Colorado fluvial/deltaic systems during the Late Quarternary: An integrated study, offshore Texas
The evolution of the Brazos and Colorado fluvial/deltaic systems over the last 190,000 years is examined. The data set includes high-resolution seismic data, lithostratigraphic data from offshore platform borings, cores and gamma-ray logs, biostratigraphic data, oxygen isotope data, and radiocarbon dates. Major periods of fluvial/deltaic deposition ...
The Texas mud blanket: Understanding fine-grained sediment flux in the NW Gulf of Mexico during the previous transgression
The evolution and source of the Texas Mud Blanket (300 km3) was determined from 26 new radiocarbon dates and from ∼3000 km of 2D seismic data. Sediment flux (km3/ka) was calculated from this combined dataset. XRD reveals its origins are mostly from the Colorado and Brazos Rivers. Between LGM and 17 ka, sediments filled the deepest accommodation ...
Glacial and tectonic development of the Antarctic Peninsula
Intermediate resolution seismic data were used to investigate the glacial history of the Pacific-Antarctic continental shelf. The objective was to determine the nature of ice sheet erosion and deposition on the continental shelf and to use these observations to reconstruct the glacial history of the region. Forearc regions underwent compression and ...
Modern sedimentary dynamics and Quaternary glacial history of Marguerite Bay, Antarctic Peninsula
Piston cores and single-channel seismic data were acquired in Marguerite Bay, Antarctic Peninsula, to determine modern sedimentary conditions and recent glacial history of the area. Seismic data in the bay shows a rugged seafloor, having numerous deep troughs and a marked lack of sediment cover, with a thin layer of sediment over crystalline basement ...
Seismic facies investigation and late Quaternary glacial history of the Chilean shelf and fjords and Antarctic Peninsula fjords
High-resolution seismic data collected in inland waters Chile and the Antarctic Peninsula (41$\sp\circ$S-65$\sp\circ$S) were interpreted using seismic facies analysis. Piston cores provide some lithologic control on the interpretation of the seismic data. These data span a latitudinal transect that encompasses temperate, subpolar and polar climatic ...
Turbidite deposition on the Bellingshausen Abyssal Plain: sedimentologic implications
A number of piston cores from the Bellingshausen abyssal plain contain gravel and sand units which are interpreted as turbidites deposited in submarine channels. Middle and outer fan deposits are lacking, although core coverage in the region is sufficient
The Antarctic Peninsula ice sheet since the Last Glacial Maximum
Antarctic is the coldest, driest, and most poorly understood climate system on the planet. Data within these pages contributes to the understanding of the Antarctic Peninsula region, a global warming "hot spot" roughly the size of the state of Texas. This dissertation has been organized into three chapters; the first chapter addresses the size and ...