塔里木盆地西北缘柯坪冲断带构造变形特征  

Structural deformation characteristics of the Kalpin thrust belt, NW Tarim

作　　者：王国林[1] 李曰俊[2] 孙建华[3] 黄智斌[3] 赵岩[2] 刘亚雷[2] 

机构地区：[1]中国石油大学地质资源与地质工程博士后流动站,北京102249 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国石油天然气股份有限公司塔里木油田分公司勘探开发研究院,新疆库尔勒841000

出　　处：《地质科学》2009年第1期50-62,共13页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家重点基础研究973项目（编号：2006CB202301）和中国科学院知识创新工程重要方向项目（编号：KCX3-SW-147）共同资助.

摘　　要：柯坪冲断带位于塔里木盆地西北缘，是新生代南天山褶皱冲断系的一部分。本文根据野外实际考察和地震剖面解释，总结了该冲断带的构造变形特征。它是发育于古生界中且以中寒武统膏盐层为主滑脱面的薄皮构造，是内部结构相对简单的叠瓦状冲断，因更新世才定型而具暴露式冲断前锋，有断层传播褶皱发育但已遭强烈剥蚀，前展式冲断。上新世晚期的冲断曾控制了磨拉石盆地发育（西域组砾岩），但该盆地已遭更新世的冲断推覆作用破坏。根据平衡剖面恢复，柯坪冲断带南部3排冲断层的总构造缩短量为29.1%～40.7%。The Kalpin thrust belt or Kalpin fold-and-thrust belt, located in the northwestern margin of the Tarim Basin, is a part of the South Tianshan fold-and-thrust system. On the basis of field investigation and seismic section interpretation, the main features of the Kalpin thrust belt could be summerized as the follows. 1 ）Only the Paleozoic rocks were involved into the thrusting, which meant that the major detachment fault was gypsum-salt layer in the Middle Cambrian. 2）The belt was characterized by imbricated thrusting, with a relatively simple inner texture. 3）The belt had an exposed thrust front, since it did not create till Pleistocene. 4）The fault-propagation folds once occurred, which were experienced violently denuded. 5）The belt was a piggyback one, with the thrusting expanded southwards. 6） A molasse basin once occurred during Pliocene, with the geological records being conglomerate of the Xiyu Formation, but the basin had been disrupted by the Pleistocene thrusting-nappe structuring. The Kalpin thrust belt consisted of the northern fold sub-belt and the southern thrust-nappe structural subbelt, and for the latter, the balanced section analysis revealved the minimal shortening rate being 29.1% to 40.7%.

关 键 词：柯坪冲断带 南天山褶皱冲断系 变形特征 更新世 塔里木西北缘 

分 类 号：P542[天文地球—构造地质学]