Late Quaternary history of Issyk Kul, Kyrgyzstan, inferred from surface, outcrop, and abyssal core sediments

伊塞克湖是世界第二大高山湖泊，位于吉尔吉斯斯坦天山山脉的一个深盆地。该湖提供了跨越数百万年的大陆性气候记录，这可能是任何其他来源无法比拟的。2011年，一个由ICDP资助的研讨会召开，会议表明，为了确定ICDP完整提案的具体钻探位置和深度，有必要对湖盆进行额外的科学调查，包括地震和沉积学研究。这里提出的项目将按照研讨会报告的要求，提供湖盆中缺失的沉积学信息。该项目的主要目的是更详细地研究伊塞克库的地表沉积物分布及其南岸晚第四纪露头，这些露头显示了约43 - 25 ka之间的湖平面高地。此外，该项目旨在首次从水深超过500米的Issyk Kul深海部分恢复6-10米长的沉积物序列，包括间冰期（全新世）和末次冰期沉积物。对（生物）地球化学、矿物学和粒度特征及其下核变化的调查，以及与地表和露头沉积物信息的相关性，将有助于检验伊塞克库尔是否能够提供气候变化和大气环流模式变化的连续高分辨率记录，以及当地高山冰川和大陆冰盖推进的相位关系。以及构造和气候变化在影响流域侵蚀速率中的作用。该项目旨在克服对Issyk Kul深海部分沉积特征和沉积速率的缺失，并提供盆地中部潜在深层钻探地点的信息，这很可能是唯一的地点，它包含了盆地的整个历史，可以追溯到几个亿年前。该项目是重新启动ICDP伊塞克库尔倡议的基础。这将有助于形成一个新的国际科学家团队，包括以前倡议的成员，也包括新成员，并在湖盆建立一个深层钻探。

Lake Issyk Kul is the world’s second largest mountain lake and occupies a deep basin in the Tien Shan range, Kyrgyzstan. The lake offers a record of continental climate spanning millions of years that is likely unmatched by any other source. An ICDP funded workshop took place in 2011 and revealed that additional scientific investigations comprising seismic and sedimentological studies in the lake basin are necessary to define specific drilling locations and depths for an ICDP full proposal.The here proposed project will provide missing sedimentological information from the lake basin, as it is requested in the workshop report. The main objectives of this project are to study in more detail the surface sediment distribution in Issyk Kul and Late Quaternary outcrops at its southern shore, which indicate lake level high-stands between ca. 43 and 25 ka. Moreover, the project aims to recover, for the first time, 6-10 m long sediment sequences comprising interglacial (Holocene) and Last glacial sediments from the abyssal part of Issyk Kul at water depths of more than 500 m. The investigation of (bio-)geochemical, mineralogical, and grain-size characteristics and their downcore variations and a correlation of the information with that derived from surface and outcrop sediments will help to examine, if Issyk Kul can provide a continuous high-resolution record of climate change and shifts in atmospheric circulation patterns, in phase relationships of local Alpine glaciers and continental ice sheet advances, and the roles of tectonics and climate change in affecting erosion rates in the catchment. This project seeks to overcome the missing knowledge of sedimentation characteristics and sedimentation rates from the abyssal part of Issyk Kul and to provide information on potential deep drilling sites in the central part of the basin, which is most likely the only site, which contains the entire history of basin back to several Myr ago. The project is fundamental to re-activate the ICDP Issyk Kul initiative. It will help to form a new team of international scientists, including members of the former initiative, but also new members, and to establish a deep drilling in the lake basin.