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Full-Text Articles in Physical Sciences and Mathematics
Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman
Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman
USF Tampa Graduate Theses and Dissertations
The East Antarctic Ice Sheet (EAIS) contains ~53 meters of sea level equivalent (SLE) ice, and observations suggest it is sensitive to ongoing and past climate change. The EAIS has traditionally been considered insensitive to climate perturbations because it is largely grounded above sea level. However, aerogeophysical surveys, oceanographic observations, and models indicate that large areas of the EAIS are grounded below sea level and contain 19.2 m SLE. Marine-based parts of the EAIS are thought to be located on inland-sloping beds that drain through marine terminating outlet glaciers, indicating large areas of the EAIS may be more sensitive to …
Reconstructing Surface Water Carbonate Ion Concentration Changes In The Eastern Equatorial Pacific Across Glacial Transitions, Lenzie Gail Ward
Reconstructing Surface Water Carbonate Ion Concentration Changes In The Eastern Equatorial Pacific Across Glacial Transitions, Lenzie Gail Ward
OES Theses and Dissertations
Today, the eastern equatorial Pacific (EEP) plays a critical role in the global CO2 budget as a major source of CO2 to the atmosphere, but recent studies suggest the region may shift to a sink for atmospheric CO2 under different climate states. Here, I focus on two transitional periods, the last deglaciation (25 kyr to present) and last glaciation (the Marine Isotope Stage (MIS) 5a-4 transition, 96 to 60 kyr), to investigate how the carbon system in the EEP responds to major climate changes. I measured B/Ca ratios in the planktic foraminifera Globigerina bulloides from core MV1014-17JC …
Diatoms And Their Response To Tectonic Gateway Changes: Case Studies From Southern Hemisphere Sites, Jason James Coenen
Diatoms And Their Response To Tectonic Gateway Changes: Case Studies From Southern Hemisphere Sites, Jason James Coenen
Graduate Research Theses & Dissertations
This dissertation covers three major transitions in Earth's climate system throughout theCenozoic (the past 65 million years of Earth's history). The progressive breakup of the super continent Pangea and the ultimate change in ocean circulation (and redistribution of heat) as a result of tectonic events dating back to the Mesozoic, primed Earth's climate system for cooling and ultimately bipolar glaciation. Climate transitions in three distinct environments were studied using absolute diatom abundance, diatom assemblages, and geochemical tracers of diatoms (i.e., biogenic silica weight%). Two geographic regions are the focus of this dissertation work. Region one is the Ross Embayment of …
Neogene Dinoflagellate Cysts From The Tropical Americas, Damian Cardenas
Neogene Dinoflagellate Cysts From The Tropical Americas, Damian Cardenas
Doctoral Dissertations
"Marine palynomorphs, mainly dinoflagellate cysts and acritarchs, constitute excellent proxies for biostratigraphic and paleoceanographic studies in neritic sequences. Neogene marine palynological studies have mostly focused on the Northern Hemisphere, resulting in the scarcity of dinoflagellate cysts and acritarchs from tropical latitudes. Forty samples encompassing the late Chattian-late Burgidalian time interval (~24.1- 17.3 Ma) in the Southern Caribbean were analyzed for their marine palynological contents. A biostratigraphic scheme for the region is proposed and includes the upper Chattian-lower Aquitanian Minisphaeridium latirictum Interval Zone (~23.9-22.0 Ma), the upper Aquitanian Achomosphaera alcicornu Interval Zone (~22.0-20.3 Ma), and the Burdigalian Cribroperidinium tenuitabulatum Interval Zone …