库鲁克塔格南部山前带中-新生代构造演化史--来自磷灰石裂变径迹的证据

摘要

Based on analysis of apatite fission track data and thermal history modeling, and combined with field geological survey, the Meso—Cenozoic tectonic evolution history in the southern piedmont zone of Kuruktag has been studied. Results showed that the formation had the characteristics of keeping the Kelatong attitude from Kuruktag uplift to the southern pied-mont direction. The age of apatite in the southern piedmont zone of Kuruktag recorded the two tectonic cooling events in 182Ma and 167—142 Ma, and the simulation of fission track thermal history indicated that Hercynian tectonic uplifted, Early—Middle Jurassic formation descended, Late Jurassic—Early Cretaceous tectonic uplifted, and Late Cenozoic tectonic uplifted, etc. Comprehensive study showed that the southern piedmont zone had been affected commonly by the early tec-tonic uplift that created in Hercynian and Yanshan movement, the Himalaya movement mainly caused the strong thrust at the upper part of fault. From the viewpoint of deposition, the deposition center of early—middle Jurassic is located in the ancient position of Queerqueke mountain.%通过对磷灰石裂变径迹数据的分析和热史模拟，结合野外地质调查，研究了库鲁克塔格南部山前带中—新生代构造演化史。结果显示，从库鲁克塔格隆起到南部山前带方向，地层具有稳定克拉通地层产状的特征。库鲁克塔格南部山前带磷灰石年龄记录了182Ma和167—142Ma两期构造冷却事件，裂变径迹热史模拟反映出海西期构造抬升、早—中侏罗世埋藏沉降、晚侏罗世—白垩纪初构造抬升和新生代晚期构造抬升等演化阶段。综合研究表明，南部山前带普遍受到海西期和燕山运动早期构造抬升的影响，喜马拉雅运动主要造成了研究区断裂上盘的强烈逆冲推覆；早—中侏罗世埋藏沉降阶段，从沉积角度看，沉积中心位于却尔却克山所在的古位置。