托斯台逆断裂-褶皱带晚第四纪活动特征

ACTIVITY CHARACTERISTICS OF TUOSITAI REVERSE FAULT-FOLD ZONE IN LATE QUATERNARY

托斯台逆断裂-褶皱带位于乌鲁木齐山前坳陷的西部，为近东西向展布的新生代逆断裂．背斜带。它主要由北单斜带、中部背斜带和南单斜带3个构造带组成，在各构造带均发育逆活动断裂。地震勘探资料显示，南单斜带与中部背斜带为滑脱体，逆断裂在深部沿滑脱面与清水河子深断裂相汇。研究表明，北单斜带与中部背斜带逆断裂断错了晚更新世堆积物，在晚更新世有显著的活动；南单斜带逆断裂断错了全新世堆积物，在全新世时期有最新活动。中部背斜带逆断裂晚更新世以来水平缩短速率为0．6～1．3mm／a；南单斜逆断裂全新世水平缩短速率为0．2～0．6mm／a。

Tuositai reverse fault-fold zone lies in west of depression in front of the mountain, Urumqi, it is EW direction cenozoic reverse fault-anticline zone. The northern monoclinal zone, middle anticline zone and southern monoclinal zone compose it, reverse active fault develop in the 3 zone. The datum of seismic prospect shows, sourthern monoclinal zone and middle anticline zone are surge bodies, reverse fault along the surge surface in the deep converge with Qingshuihezi fault. Some studies shows, the reverse fault of northern monoclinal zone and middle anticline zone break the deposit of late pleistocene, and found they are active obviously ; the reverse fault of sourthern monoclinal zone break deposit of holocene, there are new activity in holocene. The level shortening rate of reverse fault of middle anticline zone is from 0. 6 to 1.3 mm/a since late pleistocene ; level shortening rate of reverse fault of southern monoclinal zone is from 0. 2 to 0. 6 mm/a in holocene.