古太平洋板块在欧亚大陆下开始俯冲的时间一直是地学领域争论的问题之一。前人研究主要集中在东北火成岩和构造混杂岩方面，而对沉积建造及古地理环境的研究几乎处于空白。佳木斯地块是东北亚陆缘重要的构造单元之一，其东缘发育有晚三叠世南双鸭山组和早侏罗世大秃山组，属于海陆交互相-陆相碎屑岩沉积建造，动、植物化石丰富，其沉积建造形成和演化动力学机制的深入研究是探讨东亚陆缘构造体制转换的有效途径。本项目拟通过对该区晚三叠世和早侏罗世沉积地层的形成时代、物源、建造组合、生物组合以及岩石地球化学分析，查明佳木斯地块东缘早中生代地层的时空间展布，判定沉积古地理环境及其动力学背景，最终揭示古太平洋构造体系的启动时间。

It remains a controversial that the onset timing of the Palaeo-Pacific plate subduction beneath the Eurasian continent. The previous researches on the transition of tectonic regimes in the eastern Asian continental margin focus mainly on igneous rocks and accretionary complex, few are involved in the sedimentary formation and Palaeogeographic environments. The Jiamusi Massif is one of the important tectonic units in the East Asian continental margin. The Late Triassic Nanshuangyashan Formation and the Early Jurassic Datushan Formation occur in its eastern margin, and consist of clastic sedimentary formation of alternating marine and terrestrial to terrestrial sedimentary facies, with abundant animal and plant fossils. The further study on the dynamic mechanism of formation and evolution of these early Mesozoic sedimentary formations is of important implications for revealing transition timing of tectonic regimes in the east Asian continental margin. This program focuses mainly on the geochronology, provenance, sedimentary formation, biotic assemblages, and petrogeochemistry of the Late Triassic and the Early Jurassic strata, with the aim of constraining the depositional timing, their spatial distribution, sedimentary palaeogeographic environments, and geodynamic setting, and finally revealing the onset timing of the Paleo-Pacific plate subduction beneath the Eurasia.