Decadal- to orbital-scale climate variability in the Indo-Pacific Warm Pool during the past ca. 650,000 years

本次续签提案范围内拟议的调查为ICDP在印度尼西亚资助的“Towuti钻井项目”(TDP)做出了贡献。它们适用于2015年春季在Towuti湖TDP 2站点钻探的整个约137米厚、可能有65万年历史的湖泊沉积物记录，Towuti湖位于印度-太平洋暖池中心的苏拉威西岛。将对岩心复合体进行多学科的年代地层学、沉积学、地球化学和矿物学分析，以便(I)有助于沉积物记录的年代测定，(Ii)破译Towuti湖的长期发展及其形成和来自其他Malili湖的河流输入的开始，(Iii)以高达十年的分辨率重建过去约8万年来受降水控制的从Mahalano河流入的河流，(Iv)确定Towuti湖水位波动的维度和潜在原因，(V)为了解Towuti湖的混合和分层的变化提供输入以及(Vi)为S流域风化条件和土壤侵蚀的重建做出贡献。这项研究应得到对表层沉积物样品的调查的支持，这些样品是在钻探过程中采集的，并提供了有关现代沉积过程的重要信息。因此，该项目提供了部分独特的古环境和古气候数据，补充了其他国际项目对托武蒂湖的各自研究，并为相关生物项目提供了重要的背景信息。

The investigations proposed within the scope of this renewal proposal contribute to the ICDP funded ´Towuti Drilling Project´ (TDP) in Indonesia. They apply to the entire, ~137 m thick and presumably 650,000 years old lake sediment record that was drilled in spring 2015 at TDP site 2 in Lake Towuti, which is located on Sulawesi Island in the center of the Indo-Pacific Warm Pool. Multidisciplinary chronostratigraphical, sedimentological, geochemical, and mineralogical analyses shall be carried out on the core composite, in order (i) to contribute to the dating of the sediment record, (ii) to decipher the long-term development of Lake Towuti, with its formation and the onset of riverine input from other Malili lakes, (iii) to reconstruct the precipitation-controlled riverine inflow from the Mahalano River during the past ~80,000 years with up to decadal resolution, (iv) to identify the dimension and potential reasons for lake-level fluctuations in Towuti, (v) to provide input to the understanding of the variability in mixing and stratification of Towuti, and (vi) to contribute to the reconstruction of weathering conditions and soil erosion in the lake´s catchment. This research shall be supported by the investigation of surface sediment samples, which were recovered during the drilling campaign and which provide important information on modern sedimentation processes. The project thus promises partly unique paleoenvironmental and paleoclimatological data that complement respective research by other international projects on Lake Towuti, and important background information for the associated biological projects.