碎屑矿物年代对佳木斯隆起隆升时间的制约

Exhumation time of Jiamusi-uplift of northeastern China constrained by ages of detrital minerals

对佳木斯隆起周缘的勃利盆地和鸡西盆地中的早白垩世穆棱组和滴道组砂岩样品进行了系统的碎屑锆石U-Pb同位素年代学和碎屑白云母40Ar/39Ar同位素年代学研究。结果表明,滴道组和穆棱组沉积时期,没有500Ma或大于500Ma的来自佳木斯地块基底的年龄纪录,暗示佳木斯隆起在早白垩世穆棱组沉积时期尚未隆起。黑龙江东部盆地群为统一的原型盆地,结合对该区白垩纪砂岩的矿物组成和砾石统计的研究成果,认为早白垩世末东山组沉积以后佳木斯隆起开始隆升,猴石沟组沉积时期佳木斯隆起已经隆升到一定高度并为其周缘盆地提供物源,同时随着佳木斯隆起的隆升,原来早白垩世的统一盆地遭到分割破坏,形成诸多相对独立的盆地。

According to U-Pb dating of the detrital zircons and ^40Ar/^39Ar detrital micas ages of sandstone samples in Boll basin and Jixi basin around Jiamusi-uplift, it can show that no age of 500 Ma represented the Jiamusi block＇s basement or over 500 Ma ages are found in the Didao Formation and Muling Formation＇s sandstones. It indicated that the Jiamusi-uplift have not yet uplifted during the deposition of the Muling Formation. The basin group in eastern Heilongjiang should be a large-scale epicontinental basin. Combing with the analysis of sandstone provenance and conglomerate provenance, the authors think that the Jiamusi-uphft began to uplift in the late period of Early Cretaceous, was up to some certain height in the early stage of Late Cretaceous, and afforded provenance to the surrounded basins. Meanwhile, the whole basin formed in the Early Cretaceous were broke into several separated basins, as a result of the uplifting of the Jiamusi uplift.