Late Oligocene-Miocene intra-continental mountain building of the Harke Mountains, southern Chinese Tian Shan: Evidence from detrital AFT and AHe analysis
Late Oligocene-Miocene intra-continental mountain building of the Harke Mountains, southern Chinese Tian Shan: Evidence from detrital AFT and AHe analysis
复制标题
中国南部天山哈克山脉晚渐新世-中新世陆内造山运动：来自碎屑AFT和AHe分析的证据
DOI：
10.1016/j.jseaes.2019.104198
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发表时间：
2020-04-15
影响因子：
3
通讯作者：
Wang, Ying
中科院分区：
文献类型：
--
作者：
Jia, Yingying;Sun, Jimin;Wang, Ying
天山山脉是中亚最大的大陆内山带，在不同地区经历了历时性的隆升历史。该山脉现今地壳缩短速率也呈现出沿走向变化的特征，自西向东减小。哈克山脉位于天山南部中部，地壳缩短率相对较低，但在天山山脉中地势最高。本研究旨在还原哈克山脉新生代造山史。对库车坳陷古新世—上新世沉积物和现代冰碛岩进行了碎屑APT和AHe分析。26 ~ 23 Ma碎屑AFT年轻年龄分量滞后时间的突然增加表明，南天山隆升开始于晚渐新世—早中新世，这与天山山脉的区域构造活动相一致。晚中新世，哈克山基底在10 ~ 6 Ma间经历了一次快速发掘。将研究结果与已有的构造资料进行对比，认为研究区的强烈掘出与晚中新世整个天山山脉的剧烈变形相对应，这可能是塔里木与天山的加速辐合所导致的。
As the largest intra-continental mountain belt in Central Asia, the Tian Shan mountain range underwent a diachronous uplift history in different regions. The present crustal shortening rate of this mountain range is also characterized by an along-strike variation and decreases from west to east. The Harke Mountains, located in the middle part of the southern Tian Shan, accommodate a relatively lower crustal shortening rate but host the highest topography of this mountain range. This study aims to restore the Cenozoic mountain building history of the Harke Mountains. Detrital APT and AHe analyses were conducted for Paleocene-Pliocene sediments and modern moraines in the Kuqa depression. An abrupt increase in the lag time of the detrital AFT young age components at 26-23 Ma indicates that the uplift of the southern Tian Shan initiated in the Late Oligocene-Early Miocene, which is consistent with the regional tectonic activation of the Tian Shan mountain range. In the Late Miocene, the basement of the Harke Mountains underwent rapid exhumation from 10 to 6 Ma. Comparing our result with previously published tectonic data, we infer that the intense exhumation in our study area corresponds to the intensified deformation of the whole Tian Shan mountain range in the Late Miocene, which was probably driven by the accelerated convergence between the Tarim and Tian Shan.