ESH - Paleoclimatic Significance of the Wucheng Loess in China

9710051维罗苏布地球系统史的三个重要组成部分是米兰科维奇强迫、青藏隆起和全球冰量。这三种元素相互作用的陆地记录可以在中国黄土高原的古气候记录中找到。然而，大多数对中国黄土及其相关古土壤的研究都涉及到这个长达260万年的序列中的上三分之二。下部的三分之一，也就是所谓的武城组，有着非常不同的物理形态，现有的数据表明，它的成壤和磁性也与上面的三分之二不同。这些差异被认为反映了青藏高原隆升的影响越来越大，以及从以倾角和进动为主的米兰科维奇强迫向以偏心为主的米兰科维奇强迫的转变。这项建议代表了对吴城组进行基本的成土学、沉积学和矿物磁学调查的请求，目的是破译其古气候历史。我们相信，这一研究将作为中国黄土/古土壤序列其余部分研究的重要对立点，它将显著提高我们解释整个序列的古气候记录的能力，它将为海洋和陆地气候之间的耦合提供新的见解，并将为检验大气和海洋环流的计算机模型提供新的机会。

9710051 Verosub Three important elements of Earth Systems History are Milankovitch forcing, Tibetan uplift and global ice volume. A terrestrial record of the interaction of these three elements can be found in the paleoclimatic record of the Chinese loess plateau. However, most studies of the Chinese loess and associated paleosols have dealt with the upper two-thirds of this 2.6 million year-long sequence. The lower one-third, known as the Wucheng Formation, has a very different physical appearance, and the data that are available suggest that its pedogenic and magnetic properties are also different from the upper two-thirds. These differences are believed to reflect the increasing influence of the Tibetan uplift as well as a shift from Milankovitch forcing dominated by obliquity and precession to one dominated by eccentricity. This proposal represents a request for support to undertake fundamental pedogenic, sedimentologic, and mineral magnetic investigations of the Wucheng Formation with the goal of deciphering its paleoclimatic history. We believe that such a study will serve as an important counterpoint to studies of the rest of the Chinese loess/paleosol sequence, that it will significantly improve our ability to interpret the paleoclimate record of the entire sequence, that it will provide new insights about the coupling between marine and terrestrial climate, and that it will lead to new opportunities to test computer models of atmospheric and oceanic circulation.