COLLABORATIVE RESEARCH: A Detailed Chronology of the Loess-Paleosol Record of the Last Glacial/Interglacial Cycle in the North American Midcontinent

摘要/ abstract摘要：北美中大陆黄土沉积的末次冰期/间冰期黄土-古土壤详细年代学记录是第四纪长期气候变化最重要的陆地记录之一。从黄土沉积物中提取过去环境条件的高分辨率记录，只要沉积物能够准确地确定年代。本文拟应用三种独立的测年技术（10Be测年、AMS14C测年和光激发光测年），建立内布拉斯加州东部最后两个冰期/间冰期旋回黄土的高分辨率年代学。这一年代学将使我们能够准确估计这一时期大气中的尘埃通量，评估北美中大陆竞争黄土来源的相对贡献，并确定内布拉斯加州东部最后一次间冰期（Sangamon）土壤所代表的时间长度。

ABSTRACTCollaborative Research: A detailed chronology of the Loess-Paleosol Record of the last glacial/Interglacial Cycle in the North American MidcontinentLoess deposits represent one of the most important terrestrial records of long-term Quaternary climatic change. High-resolution records of past environmental conditions can be extracted from loess deposits provided that the deposits can be accurately dated. We propose to apply three independent dating techniques (10Be inventory, AMS14C, and Optically Stimulated Luminescence) to develop a high-resolution chronology for loess of the last two glacial/interglacial cycles in eastern Nebraska. This chronology will enable us to make accurate estimates of dust flux to the atmosphere over this time period, to evaluate the relative contribution of competing loess sources in the North American Midcontinent, and to determine the length of time represented by the last interglacial (Sangamon) soil in eastern Nebraska.