The timing of the collision between the Songnen–Zhangguangcai Range Block (SNZRB) and the Jiamusi Block (JMSB) is poorly constrained; however, detrital zircons may provide crucial information on the history of this collision. This study focuses on the Yangmugang and Tumenling formations of the Yimianpo Group in the southeastern SNZRB, which were previously thought to have been deposited during the closure of the Mudanjiang Ocean. Detrital zircon U-Pb dating was carried out to constrain the age, provenance, and tectonic setting of the Yangmugang and Tumenling formations, and ultimately the timing of the final closure of the Mudanjiang Ocean. The detrital zircon grains in the two formations yield similar age spectra, with two major age peaks at 275 Ma and 280 Ma, 512 Ma and 525 Ma, respectively. Given the age of the youngest group and that of a granite intrusion, the Yangmugang and Tumenling formations were probably deposited during the middle Permian. The detrital zircon ages also suggest that the Paleozoic igneous rocks distributed across the eastern SNZRB were the major source of the zircons in the formations. Combined with evidence for synchronous arc magmatism, this shows that the Yangmugang and Tumenling formations were likely deposited at a convergent margin and that the collision between the SNZRB and JMSB occurred after the late Permian.

松嫩—张广才山脉地块（SNZRB）与佳木斯地块（JMSB）碰撞的时间约束较差；然而，碎屑锆石可能提供关于这次碰撞历史的重要信息。本次研究重点关注新北裂带东南部伊面坡群的杨木岗组和土门岭组，这些组以前被认为是在牡丹江洋闭合期间沉积的。进行了碎屑锆石 U-Pb 测年，以确定杨木岗和土门岭地层的年龄、物源和构造背景，并最终确定牡丹江洋最终闭合的时间。两个地层中的碎屑锆石颗粒产生相似的年龄谱，两个主要年龄峰值分别为 275 Ma 和 280 Ma、512 Ma 和 525 Ma。鉴于最年轻组的年龄和花岗岩侵入体的年龄，杨木岗和土门岭地层可能沉积于二叠纪中期。碎屑锆石年龄也表明，分布在 SNZRB 东部的古生代火成岩是地层中锆石的主要来源。结合同期弧形岩浆作用证据，表明杨木岗组和土门岭组很可能沉积于会聚边缘，SNZRB与JMSB的碰撞发生在晚二叠世之后。