GRGC: Reconstruction of Water Balance Fluctuations During the Last Deglaciation Based on Glacial/Lacustrine Systems in the Western Great Basin

9417810菲利普斯最后一次冰川的结束是由一系列重大而突然的气候事件完成的。显然，大气中水蒸气输送的变化在冰川消融过程中发挥了关键作用。尽管这些事件显然导致了全球冰川条件的分离，但在北大西洋地区以外，人们对这一系列事件的细节知之甚少。在这个项目中，我们建议应用新的地质年代学和古水文学方法来解释单一的封闭流域的冰川和湖泊数据：大盆地西部的古欧文斯河系统。我们将应用质谱学U/Th和宇宙成因的~(36)Cl测年来完善现有的湖相沉积和末端盆地岸线的年代学。这一年表将与欧文斯河源头内华达山脉东部冰川沉积物和表面的宇宙成因36Cl和碳-14的年表进行比较。这些新的和改进的年表将使冰川和湖泊系统的事件序列能够相互比较。然后，将使用瞬时能量和质量平衡数值模型，根据气候驱动力对组合序列进行定量解释。最后，可以将重建的气候历史与最近的全球条件冰芯和海洋沉积物记录进行比较，以评估大陆环境中温度和水蒸气输送的变化如何反映了全球事件。

9417810 Phillips The end of the last glaciation was accomplished by a series of major and abrupt climatic events. It is clear that changes in the atmospheric transport of water vapor played a key role in the deglacial process. Although these events apparently resulted in a global secession of glacial conditions, the details of the sequence of events is poorly known outside the North Atlantic region. In this project we propose to apply new geochronological and paleohydrological methods to the interpretation of glacial and lacustrine data in a single, closed drainage basin: the paleo-Owens River system in the western Great Basin. We will apply mass spectrometric U/Th and cosmosgenic 36Cl dating to refining the existing chronology for lacustrine deposits and shorelines in the terminal basins. This chronology will be compared with one derived from cosmosgenic 36Cl and carbon-14 for glacial deposits and surfaces in the eastern Sierra Nevada, at the headwaters of the Owens River. These new and refined chronologies will allow the sequence of events for the glacial and lacustrine systems to be compared with each other. The combined sequence will then be quantitatively interpreted in terms of climatic driving forces, using a transient numerical energy and mass balance model. Finally, the reconstructed climatic history can be compared with recent ice core and marine sediment records of global conditions to assess how the global events were reflected by changes in temperature and water vapor transport in a continental setting.