摘要
柯坪断隆新生代推覆构造是南天山南缘冲断系统的一部分,断隆上多排逆冲岩席被数条横向断裂复杂化,致使不同地段岩席排数不等,各排岩席在走向上的对应关系不明,形成了十分奇特的山弯构造。逆冲岩席的变形特点是南天山新生代造山运动的重要表征。笔者通过卫星影像分析和野外路线地质调查,对横向断裂切割各排逆冲岩席之切点部位的构造特征及岩席内部中小型构造所显示的成因信息进行了详细分析,据此,对复杂岩席在走向上进行了连接,对其数量进行了识别。在此基础上,提出了复杂岩席成因的斜冲褶皱模式,即在北西向应力场持续作用下,岩席向南东斜冲,并在其水平位移分量作用下,沿走向发生褶皱和斜冲错断;横向断裂是多排岩席褶皱翼部扭性断层的发展和连通。
Cenozoic nappe structures in the Kalpin fault uplift constitute a part of southern South Tianshan marginal thrust system. The number of nappe sheets is different from place to place, and the corresponding relationship of the nappe sheets in different parts is not clear because of the disturbance of the dip faults, which forms an unique orocline. The Cenozoic orogenic movement of southern South Tianshan is largely characterized by the deformation of the nappe sheets. By means of TM image interpretation and field geological investigation, the structural features at the intersects between the dip faults and the nappe sheets and the minor structures which can show the formation information of the nappe sheets were studied in detail. On the basis of the study, the disturbed nappe sheets in different parts of the uplift were connected successfully and the number of the nappe sheets was identified as well. A tectonic model has been suggested, which holds that the disturbed nappe sheets resulted from folding and fault slipping in the striking direction of the nappe sheets when they thrusted southeast under the NW-striking maximum principal compression stress, and the dip faults originated from the minor faults that occurred in the wings of the folded nappe sheets.
出处
《中国地质》
CAS
CSCD
北大核心
2009年第2期322-333,共12页
Geology in China
基金
核工业地质局基础地质研究项目(遥D0701)资助。
关键词
柯坪断隆
推覆岩席
走向连接
成因分析
Kalpin fault uplift
nappe sheet
nappe sheet connection
formation mechanism
