High-resolution Stratigraphy: Application to Hydrologic- Climatic Reconstruction in Southwestern United States

这是一项研究的更新，旨在建立一个气候参考部分，用于检查末次盛冰期（约 35Ka 至 12.5ka）之前、期间和之后发生的异常大且快速的气候变化的同步性。 新墨西哥州中部水文封闭的埃斯坦西亚盆地特别适合作为参考剖面，因为它以前位于极锋急流之下，因为它不间断的高分辨率地层和古生物记录，因为它记录了对气候强迫的强烈、清晰和可测量的响应。 丰富的介形虫和花粉可用于 AMS 测年。 由于积累率高、生物扰动弱，采样间隔对气候变化的实际分辨率小于十年。 对沉积物成分、氧 18 和碳 13 以及水化学（介形类物种丰度）的近距离（约 50 年）分析，以及质量平衡计算和水文模型将用于在几个世纪到几千年的时间尺度上量化 P-E。 与以更紧密的间隔分析的成分和其他变化相关的灰度图像将表征年际至世纪尺度的气候变化。 记录的气候变化模式包括约 2000 年的高位和低位、非常强的约 200 至 250 年、蒙德规模振荡和约 20 年的周期。 基于AMS测年的更准确的年龄模型和年代地层学将确定Estancia地点在盛冰期和同位素第三阶段后期记录的异常大且快速的气候波动的时间。Estancia参考部分将是第一个完整的、基于陆地的高分辨率年代学，用于记录这一重要时间间隔内的气候变化。 它将作为关联和解释区域气候变化以及半球和全球气候事件的基础。

This is a renewal of research to establish a climatic reference section for examining the synchroneity of the exceptionally large and rapid changes in climate that occurred before, during, and after the last glacial maximum (~35Ka to 12.5ka). The hydrologically closed Estancia basin in central New Mexico is especially well suited as a reference section because of its previous location under the Polar Front Jet Stream, because of its uninterrupted high-resolution stratigraphic and paleontologic record, and because it recorded a strong, clear, and measurable response to climate forcing. Abundant ostracodes and pollen are available for AMS dating. The sampling interval, owing to a high accumulation rate and weak bioturbation, has a practical resolution for changes in climate of less than a decade. Closely spaced (~50- yr) analyses of sediment composition, oxygen 18 and carbon 13, and hydrochemistry (ostracode species abundance), along with mass- balance calculations and a hydrologic model will be used to quantify P-E on the time scale of centuries to millennia. Gray- scale images linked to compositional and other changes analyzed at more closely spaced intervals will characterize interannual to century-scale climatic variability. Patterns of recorded climatic variability include ~2000-yr highstand and lowstands, very strong ~200-to 250-yr, Maunder-scale oscillations, and ~20-years cycles. A more accurate age model and chronostratigraphy based on AMS dating of abundant ostracodes will determine the timing of the unusually large and rapid climatic fluctuations recorded at the Estancia site during the glacial maximum and during the later part of isotope stage 3. The Estancia reference section will be the first complete, land-based high-resolution chronology for changes in climate during this important time interval. It will serve as the basis for correlating and interpreting regional shifts in climate as well as hemispheric and global climatic events.