库车盆地中新生代构造演化: 磷灰石裂变径迹证据

通过对库车河剖面14个样品磷灰石裂变径迹的测试, 研究了库车盆地及其源区的构造演化.根据表观年龄和地层年龄关系, 将结果分成8个退火样品和6个碎屑样品.退火样品年龄从北向南从136~93.7 Ma, 记录了构造发育自造山带向盆地扩展的运动样式.其中09dk-6, 09dk-7, 09dk-8和09dk-11未通过X2检验, 分析认为与后期构造活动有关, 分解得到最年轻的年龄组记录了库如力向斜, 捷斯德里克背斜和阿合断层分别在74.4 Ma、24.2 Ma和50.8 Ma的最新一期活动.碎屑磷灰石得到了250 Ma、160 Ma和100 Ma3个明显的静态峰.结合热模拟研究表明, 研究区存在250 Ma、160 Ma、100 Ma和20 Ma四期构造隆升, 是对亚洲南缘多期地体碰撞增生的响应. 

Mesozoic-Cenozoic Tectonic Evolution of the Kuqa Basin: Evidence from Apatite Fission-Track Data

Fourteen samples were collected from the Kuqa River section for apatite fission track analysis in order to investigate the thermal history of the Kuqa Basin and its sedimentary provenance. By comparing the apparent ages of samples with the related strata ages, the samples can be divided into two groups: the annealed group and the detrital group (unreset samples).The AFT ages become younger from 136 Ma to 93.7 Ma from the Tianshan Mountain to the Kuqa Basin, probably recording a basin-ward propagation of the thrust-fold belt. Samples 09dk-6, 09dk-7, 09dk-8 and 09dk-11 failed the X2 test likely due to the subsequent tectonic deformation. The youngest ages extracted from these samples probably record the latest activities of the Kuruli Syncline, Jiesidelike Anticline and the A'ge Fault at 74.4 Ma, 24.2 Ma and 50.8 Ma, respectively. The detrital samples have three peak ages at 250 Ma, 160 Ma and 100 Ma respectively. Thermal history modeling reveals four periods of denudation at 250 Ma, 160 Ma, 100 Ma and 20 Ma in the Kuqa basin and the Tianshan Mountains. The multi-stage denudation is linked to far-field effects resulted from the collision and accretion of terranes along the southern Asian continental margin.