摘要
依据帕米尔—西昆仑北麓新生代前陆褶皱冲断带 3条构造剖面的详细分析 ,发现帕米尔—西昆仑北麓除山根地带发育高角度断层外 ,基本上以低角度逆掩断层为主 ,形成与逆冲推覆构造相关的褶皱变形。乌泊尔地区表现为由山脉向塔里木盆地滑移的隐伏冲断层和上覆褶皱 ;苏盖特—齐姆根—甫沙地区表现为山前的三角带和向盆地扩展的两排背斜带。帕米尔—西昆仑北麓前陆褶皱冲断带的主要构造变形时间始于上新世早期 (距今约 4.6Ma) ,断层、褶皱的变形时代由山前向盆地逐步变新 ,变形强度由山脉向塔里木盆地逐步减弱。帕米尔—西昆仑北麓前陆褶皱冲断带的构造缩短量为 2 0～ 70km ,缩短率为 35 %～ 5 0 %。
The Pamir Western Kunlun foreland fold and thrust belt was very important to study intraplate deformation in central Asia and hydrocarbon exploration. Based on detailed structural analysis of three cross sections which synthesized by seismic profiles, outcrops and drilling data in the area, the structural characters were studied and structural models of the Pamir Western Kunlun foreland fold and thrust belt established. In the foreland fold and thrust belt there mainly were low angle blind thrusts in addition to high angle thrusts along the mountain's piedmont. Two structural styles were presented: the thrust related structures due to underlying thrusts slipping from orogen to foreland basin in the Wupor zone, and the triangle zones formed by stack of 2～3 imbricate thrust sheets which plugged in undeformed strata towards foreland basin by means of wedges, so as to creat three rows of folded belt in the Sugaite Qimugen Fusha zone. The main tectonic deformation in the Pamir Western Kunlun foreland fold and thrust belt started in Early Pliocene (about 4.6 Ma ago), and migrated gradually from the orogen to the foreland basin, with the faulting and folding becoming younger and weakened in the basin. The tectonic shortening amount increased from 23.3 km in the Wupor zone to 68 km in the Fusha zone, but the tectonic shortening rate kept in the range of 35%～50%. In addition, the possible hydrocarbon traps in the Pamir Western Kunlun foreland fold and thrust belt were analyzed.
出处
《地质科学》
CAS
CSCD
北大核心
2004年第2期260-271,共12页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家自然科学基金项目 (批准号 :49972 0 77)资助成果
关键词
前陆褶皱冲断带
地震剖面叠瓦逆掩席
三角带
构造缩短率
Foreland fold and thrust belt, Seismic reflection profiles, Imbricate thrust sheet, Triangle zone, Tectonic shortening rate, Pamir Western Kunlun
