Physical Sciences and Mathematics Commons^™

Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella

USF Tampa Graduate Theses and Dissertations

Warm, intermediate-depth Southern Ocean waters are implicated in recent Antarctic ice mass loss. Direct observations of Antarctic Ice Sheet (AIS) retreat are temporally limited, necessitating paleoceanographic records of ocean-ice interactions during past warm climate intervals. Deepsea and ice-proximal sediments record orbitally-paced glacial-interglacial fluctuations in AIS volume during the Plio-Pleistocene (last 5 million years; Ma), but the total contribution of the AIS and the role of ocean heat in these fluctuations remain unresolved. To address the response of Antarctica’s ice sheets to changing ocean temperatures during the Plio-Pleistocene, International Ocean Discovery Program (IODP) Expedition 374 recovered sediments from the Ross Sea …

Mid-Holocene Speleothem Climate Proxy Records From Florida And Belize, Anna L. Pollock

USF Tampa Graduate Theses and Dissertations

As global temperatures rise due to anthropogenic climate change, water resources, thus economies, are threatened. A geologically recent period of increased temperatures is the mid-Holocene and an investigation of its climate may allow for a better understanding of future precipitation and changes to regional water resources. The regions of interest are tropical Northern Central America and subtropical North America with Belize and Florida representing each climate zone. By reconstructing mid-Holocene climate in Florida and Belize, I hope to provide a better understanding of how increased temperatures and a reduced latitudinal temperature gradient impacts both precipitation patterns and variability. Today, drivers …

Layer-Bounding Surfaces In Stalagmites As Keys To Better Paleoclimatological Histories And Chronologies, Loren Bruce Railsback, Pete D. Akers, Lixin Wang, Genevieve A. Holdridge, Ny Riavo Voarintsoa

International Journal of Speleology

Petrographic recognition of layer-bounding surfaces in stalagmites offers an important tool in constructing paleoclimate records. Previous petrographic efforts have examined thickness of layers (a possible proxy for annual rainfall) and alternation of layers in couplets (a possible indicator of seasonality). Layer-bounding surfaces, in contrast, delimit series of layers and represent periods of non-deposition, either because of exceptionally wet or exceptionally dry conditions.

Two types of layer-bounding surfaces can be recognized according to explicitly defined petrographic criteria. Type E layer-bounding surfaces are surfaces at which layers have been truncated or eroded at the crest of a stalagmite. Keys to their recognition …

Annually Laminated Speleothems: A Review, Andy Baker, Claire L. Smith, Catherine Jex, Ian J. Fairchild, Dominique Genty, Lisa Fuller

International Journal of Speleology

This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.

Climatic And Structural Controls On The Geomorphology Of Wadi Sana, Highland Southern Yemen, Joshua Michael Anderson

USF Tampa Graduate Theses and Dissertations

Middle Holocene climate change forced significant environmental response and influenced human activities throughout southern Arabia. Climate models and proxy data indicate that climate along the southern Arabian peninsula changed from a moist phase, spanning the early to middle Holocene, to an arid phase, which persisted for the last ca. 5,000 years. A weakening and southward shift of the Southwest Indian Monsoon System, forced by northern hemisphere insolation variations in the precession band and/or glacial boundary conditions, is suggested as the mechanism for the abrupt shift to more arid conditions. Geoarchaeological evidence suggests that agriculture was more widespread and evolved alongside …

Activators Of Luminescence In Speleothems As Source Of Major Mistakes In Interpretation Of Luminescent Paleoclimatic Records, Y. Y. Shopov

International Journal of Speleology

This work summarizes the main results of the operation of the International Program “Luminescence of Cave Minerals” of the commission on Physical Chemistry and Hydrogeology of Karst of UIS of UNESCO in the field of activators of speleothem luminescence. It discusses Activators of Luminescence in Speleothems as a source of major mistakes in the interpretation of luminescent paleoclimatic records. It demonstrates the existence of 6 types of luminescence of speleothems and cave minerals in dependence of the type of the luminescence center and its incorporation in the mineral. 24 different activators of photoluminescence of speleothem calcite and 11 of aragonite …

Paleocollapse Structures As Geological Record For Reconstruction Of Past Karst Processes During The Upper Miocene Of Mallorca Island, P. A. Robledo Ardila, J. J. Durán, L. Pomar

International Journal of Speleology

Paleocollapse structures and collapse breccias are one of the major features for paleokarst analysis and paleoclimate record. These are affecting the Llucmajor and Santanyí carbonate platforms. These platforms, of southern and eastern Mallorca respectively, are a good example of progradation reef platform in the western Mediterranean. The Santanyí platform is constituted of two sedimentary units, both affected by paleocollapse structures: (1) The Reef Complex attributed to the upper Tortonian-lower Messinian; (2) Santanyí Limestone attributed to the Messinian. There are abundant paleocollapse outcropping in the Reef Complex and Santanyí Limestone units. These structures have been produced by roof collapse of caverns …

The Role Of The Environmental Archaeologist In The Study And Reconstruction Of Cave Palaeoclimate, Maria Gkioni

International Journal of Speleology

Man and environment are engaged in a continuous battle to impose themselves on one another. The results are found in environmental modifications or climatic oscillations and, as far as man is concerned, in the different character of cultural remains. Man responds to environmental changes by migrating or evolving technological innovations, both of which leave important remains that the archaeologist is called on to recognise and interpret during and after an excavation. They both also reflect the sociocultural responses to climatic stress. This paper refers to a specific case study, caves, which housed man and his activities from the very early …