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Full-Text Articles in Physical Sciences and Mathematics
Post-Impact Light Vapor Incorporation During Lunar Formation Based On Triple Oxygen Isotopes, Erick J. Cano
Post-Impact Light Vapor Incorporation During Lunar Formation Based On Triple Oxygen Isotopes, Erick J. Cano
Earth and Planetary Sciences ETDs
Initial triple oxygen isotope analyses of lunar samples showed them to be indistinguishable from Earth, which led to numerous papers aimed at explaining the similarities. Recent high-precision analyses suggested either a subtle enrichment in Δ'17O or virtually no difference between the Earth and Moon. Herein we expand on previous studies by correlating the triple oxygen isotope measurements with different lunar lithologies. We show that these data can be explained by mixing between a light vapor phase, generated during the Giant Impact, and the residual material from the proto-lunar impactor ‘Theia’. There is a general decrease in Δ'17 …
Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter
Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter
USF Tampa Graduate Theses and Dissertations
Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …
A Speleothem Record Of Climate Variability In Southwestern North America During Marine Isotope Stage 3, Justin G. Peinado
A Speleothem Record Of Climate Variability In Southwestern North America During Marine Isotope Stage 3, Justin G. Peinado
Earth and Planetary Sciences ETDs
During Marine Isotope Stage 3 (MIS-3) of the last glacial period, there were rapid transitions between warm and cold climates referred to as Dansgaard-Oeschgerr (DO) events. In Southwestern North America (SWNA), two speleothem paleoclimate records document changes in moisture source delivery in response to DO-events during MIS-3, but do not address potential changes in effective moisture for the region. In this study, we introduce a new high-resolution speleothem paleoclimate record from Carlsbad Cavern in the Guadalupe Mountains. The speleothem, sample BC-5, grew continuously from 46-31 kya during the latter half of MIS-3, based on U-Th dating. We also tied stable …
Hydrogen, Carbon, And Oxygen Isotopes In Prosopis Sp. Trees: A New Climate Proxy For Holocene Paleoclimate In The Atacama Desert, Chile, Elizabeth Joy Olson
Hydrogen, Carbon, And Oxygen Isotopes In Prosopis Sp. Trees: A New Climate Proxy For Holocene Paleoclimate In The Atacama Desert, Chile, Elizabeth Joy Olson
Graduate Research Theses & Dissertations
The spatial ubiquity of trees in terrestrial ecosystems worldwide facilitates the use of stable isotope research in tree-rings to address a wide-range of interdisciplinary questions related to climate, ecology, archaeology, and hydrology. This dissertation focuses on the development and application of Prosopis tamarugo tree-ring stable isotope records as a paleoclimate proxy for the Atacama Desert, Chile. Current paleoclimate proxies from this region lack the spatial and temporal resolution to quantify a causal mechanism for observed Holocene hydroclimate variability. P. tamarugo tree-ring isotopes provide a high-resolution proxy that facilitates the reconstruction of hydroclimate variability at a regional scale. In order to …