北极海冰变化不仅显著影响全球变化，而且其对全球变化响应异常敏感。然而，全新世北极海冰演化机制仍不明确。北极东西伯利亚陆架是北冰洋季节性海冰形成的关键源区，其沉积连续且速率较高，可记录高分辨率的全新世海冰演化信息。本项目以该陆架上LV77-36-1岩心沉积物为主要研究材料，在放射性碳年代地层框架、沉积环境和潜在物源区沉积学分析基础上，利用粒度、粘土矿物、Sr-Nd同位素和海冰生物标志物IP25及甾醇等指标，探讨全新世不同时期研究区沉积物来源及其沉积机制，并以此为基础，从无机和有机地球化学两方面重建全新世北极东西伯利亚海冰演化历史。最后，运用数值模拟手段，结合现代海冰理论研究成果，重点探究中全新世以来海平面相对稳定时期（~7.0 ka）北极东西伯利亚海冰演化的主控因素及其对全球气候变化的响应机制。该项目将加深对北冰洋陆架沉积机制的认识，并可为预测未来全球变暖背景下北冰洋海冰演化提供历史依据。

Arctic sea ice not only significantly influences global changes but also sensitively responds to their variations. However, the controlling mechanisms of Holocene Arctic sea ice evolutions remain unclear until now. The East Siberian shelf is one of the most important source areas of the Arctic seasonal sea ice. Based on the relatively high sedimentation rate on the continental shelf, the high-resolution and continuous variations in sea ice during the Holocene Epoch can be recorded in the sedimentary strata. In this project, one sediment core, named LV77-36-1, which was collected from the East Siberian shelf during the period of the first joint Arctic cruise between China and Russia, will be used as a major material. Coupled with the age model on the base of radiocarbon age data, the paleoenvironmental analyses, and the sedimentary analyses of potential source areas, this project tends to apply the grain sizes, clay minerals, and Sr-Nd isotopes of terrigenous sediment to trace the sediment source, and thus to study the Holocene deposition mechanisms of the study area in the context of sea-ice evolution during different periods. On this basis, the project tends to apply the results of sediment source analyses and sea-ice biomarkers IP25 and sterol to qualitatively and semi-quantitatively reconstruct the variations in sea ice on the Arctic East Siberian Shelf during the Holocene Epoch from the perspectives of inorganic and organic proxies, respectively. Finally, the modern climate theories will be combined and the numerical modeling will be utilized to reveal the major controlling factors of sea-ice evolution on the Arctic East Siberian Shelf and its response to the global climate changes since 7.0 ka when the sea level was highstand and changed slightly. Thus, the findings of this project will help us not only to further understand the Arctic continental shelf sedimentary process but also to provide the geological references to forecast the future evolution of Arctic sea ice in the context of global warming.