Doctoral Dissertation Research: Reconstruction of Late Quaternary Climate Patterns from Lacustrine, Aeolean, and Alluvial Deposits of the Salt Basin in West Texas

9405247柯里为了更好地了解未来气候变化的可能方向和后果，地理学家和其他地球科学家必须首先识别和了解过去发生的气候变化的动态。古气候变化可以通过研究地貌系统的响应来分析，地貌系统的记录保存在不同地貌的地层记录和其他特征中。这一博士论文研究项目将研究德克萨斯州西部盐湖晚第四纪期间的环境变化。来自普拉亚盆地及其附近曾经是湖床的许多不同地点的沉积物将被收集起来，并使用各种测年程序进行分析。将对Playa底板下的地层剖面进行检查，以确定湖泊沉积物中包含的物质，从而提供短期气候变化的证据。游乐场旁边的外围部分包含石膏沙丘沉积中风沙活动的证据。沿普拉亚边缘的其他特征，如唾液和海滩脊，允许解释深水湖泊过程。在远离游乐场的地方，风和流水产生的地貌记录了形成环境的可变性。将用于分析来自样品地点的材料的研究技术包括热释光和光学模拟发光(TL/OSL)测年、放射性碳测年和稳定同位素速率分析。这项研究将为大平原南部气候和景观变化的年表提供有价值的新见解。通过这样做，它将进一步全面了解上一次大冰川之后北美的环境变化，从而促进对地球系统历史的理解，这是美国全球变化研究计划的一个主要方面。作为博士论文改进奖，该奖项也将支持一个有前途的学生建立一个强大的独立研究事业。

9405247 CURREY In order to better understand the possible direction and consequences of future climate changes, geographers and other earth scientists must first identify and understand the dynamics of climatic changes that have occurred in the past. Paleoclimatic changes can be analyzed through examination of the responses of geomorphic systems, records of which are preserved in stratigraphic records and other characteristics of different landforms. This doctoral dissertation research project will examine environmental change during the late Quaternary Period in the Salt Basin of western Texas. Deposits from a number of different sites in and near playa basins that once were lakebeds will be gathered and analyzed using a variety of dating procedures. Stratigraphic sections beneath the floor of the playa will be examined to identify materials contained within lake sediments, thereby providing evidence of short-term climatic shifts. Peripheral sections beside the playas contain evidence of aeolian activity in gypsum dune deposits. Other features along the playa margin, such as spits and beach ridges, permit interpretation of deep-water lacustrine processes. Further away from the playas, landforms produced by wind and running water record variability of formative environments. Among the research techniques that will be used to analyze materials derived from sample sites are thermoluminescence and optically simulated luminescence (TL/OSL) dating, radiocarbon dating, and stable isotope rate analysis. This research will provide valuable new insights about the chronology of climate and landscape change in the southern Great Plains. In doing so, it will further the comprehensive picture of environmental change in North America in the wake of the last major glaciation, thereby advancing understandings of Earth system history, a major facet of the U.S. Global Change Research Program. As a doctoral dissertation improvement award, this award also will pr ovide support to enable a promising student to establish a strong independent research career.