Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"U/Th dating"”.
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U-Th Dating of lacustrine carbonates
… have been hindered by poor chronology. Uranium-thorium (U-Th) dating has the potential to fill a gap in current geochronological tools for such archives, but past attempts have been confounded by poor understanding of the complex makeup of lacustrine carbonates, leading to misguided conclusions …
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Deep-lake carbonates and speleothems as high-resolution archives of paleohydrology in the Bonneville Basin, UT
… focus on developing precisely dated records from the Bonneville Basin, a large basin in the eastern U.S. Great Basin. This region is known to have been highly sensitive to hydroclimate changes during the past glacial period; closed-basin lakes in this region have been studied for over a century. …
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GEOCHEMISTRY AND PETROGRAPHY OF SPELEOTHEMS FROM TURKEY AND IRAN: PALAEOCLIMATE AND DIAGENESIS
Abstract Speleothems contain key archives of palaeoclimatic information, which can be interpreted through multiple geochemical and petrographic proxies, and precisely dated by Uranium Series dating. As U/Th dating is only viable for samples up to approximately 700 kyr of age, U/Pb dating must be …
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U-series dating, geochemistry, and geomorphic studies of travertines and springs of the Springerville area, east-central Arizona, and tectonic implications.
… CO2 springs and related travertine deposits of the Springerville area of east-central Arizona provide an exceptional field laboratory for understanding travertine-depositing spring systems. U-series dating of travertines provides an opportunity to unravel paleohydrologic and neotectonic …
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Applying U-Th Disequilibrium to Dating Siliceous Sinter
Continental hydrothermal systems are critical avenues for the crustal transport of heat and mass captured for geothermal energy and mineral exploration. Thus, understanding their temporal evolution and longevity is important for resource characterization. In particular, high temperature reservoirs …
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Insular adaptations in the appendicular skeleton of Sicilian and Maltese dwarf elephants
This thesis investigates the evolution of Pleistocene insular proboscideans from the centralwestern Mediterranean (Palaeoloxodon species from Sicily, Malta, Favignana) and a mammoth (Mammuthus lamarmorai) from Sardinia, with a particular emphasis on the anatomy of the limbs. Differences in the …
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Basic studies for the incorporation of uranium in sediments
… Investigation on sorption interactions with soil, sediments and rocks are important to understand uranium mobility, in order to correct U/Th dating methods in open systems. Uranium immobilization is possible due to reduction U(VI) to U(IV), adsorption or co-precipitation. Under oxidizing …
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Multi-timescale mechanics of an active low-angle normal fault
… moderately-to-highly extended regions. Slip on these high-offset low-angle normal faults remains perplexing due to their apparent misorientation relative to Andersonian principal stress directions. Classic fault mechanical theory predicts that normal faults should frictionally lock up and become …
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Dating and Interpretation of Secondary Carbonate Deposits from the Last Interglacial
The age of secondary carbonate deposits has been determined via U/Th dating. According to the investigation of speleothems from the high Alpine Spannagel Cave (Zillertal Alps, Austria), a first warming occurred 135,000 years (135 kyr) ago. Sinter growth was interrupted from 130 kyr to 126 kyr, …
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Travertine from Egypt's Western Desert: a terrestrial record of North African paleohydrology and paleoclimate during the late Pleistocene
The "Green Sahara" pluvial phases that alternated with North African hyper-aridity during the Pleistocene are well recognized in tropical and Mediterranean marine records. However, comparatively few studies have investigated the terrestrial expression of these pluvials, in part because of the …