In order to provide references of the subduction process of the Paleo‐Pacific Plate beneath the Jiamusi Block, this paper studied the clastic rocks of the Nanshuangyashan Formation using modal analysis of sandstones, mudstone elements geochemistry, and detrital zircon U–Pb dating. These results suggest the maximum depositional age of the Nanshuangyashan Formation was between the Norian and Rhaetian (206.8 ±4.6 Ma, mean standard weighted deviation (MSWD) = 0.17). Whole‐rock geochemistry of mudstone indicates that source rocks of the Nanshuangyashan Formation were primarily felsic igneous rocks and quartzose sedimentary rocks, which were mainly derived from the stable continental block and a magmatic arc. Detrital zircon analysis showed the Nanshuangyashan Formation samples recorded four main age groups: 229–204 Ma, 284–254 Ma, 524–489 Ma and 930–885 Ma, and the provenances were attributed to the Jiamusi Block and a Late Triassic magmatic arc near the study area. Furthermore, the eastern Jiamusi Block was a backarc basin, affected by the subduction of the Paleo‐Pacific Plate in the Late Triassic, but the magmatic arc related to the subduction near the study area finally died out due to tectonic changes and stratigraphic erosion.

中文翻译：

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古太平洋板块俯冲到佳木斯地块：来自佳木斯地块东部早期中生代沉积岩的证据

为了对佳木斯地块下古太平洋板块的俯冲作用提供参考，本文通过对砂岩，泥岩元素地球化学和碎屑锆石U-Pb年代的模态分析研究了南双鸭山组碎屑岩。这些结果表明，南双鸭山组的最大沉积年龄在Norian和Rhaetian之间（206.8±4.6 Ma，平均标准加权偏差（MSWD）= 0.17）。泥岩的全岩地球化学表明，南双鸭山组烃源岩主要为长英质火成岩和石英质沉积岩，主要来源于稳定的陆块和岩浆弧。碎屑锆石分析表明，南双鸭山组样品记录了四个主要年龄组：229-204 Ma，284-254 Ma，524–489 Ma和930–885 Ma，物源归因于研究区附近的佳木斯地块和晚三叠世岩浆弧。此外，东部佳木斯地块是晚三叠世古太平洋板块俯冲作用的后弧盆地，但由于构造变化和地层侵蚀，与俯冲有关的岩浆弧最终消失了。