柴达木盆地西部地区新生代演化特征与青藏高原隆升  

Cenozoic uplift of the Tibetan Plateau:Evidence from tectonic-sedimentary evolution of the Western Qaidam Basin

作　　者：王亚东[1,2] 张涛[2] 迟云平[2] 刘艳蕊[2] 张志高[2] 李仕远[3] 方小敏[4,2] 张跃中[3] 

机构地区：[1]中国科学院油气资源研究重点实验室,甘肃兰州730000 [2]兰州大学西部环境教育部重点实验室和资源环境学院,甘肃兰州730000 [3]中国石油天然气股份有限公司青海油田分公司勘探开发研究院.甘肃敦煌,736202 [4]中国科学院青藏高原研究所盆地与资源环境研究中心,北京100085

出　　处：《地学前缘》2011年第3期141-150,共10页Earth Science Frontiers

基　　金：中国科学院重要创新方向性项目(KZCX2-YW-104,KZCX2-YW-Q09-04);国家重点基础研究发展计划“973”项目(2005CB422001)

摘　　要：通过对柴达木盆地西部地区(柴西地区)地震剖面构造-沉积相演化的分析,结合基底岩性及区域构造运动历史,重建了柴西地区新生代构造-沉积动态演化框架。柴西地区新生代以来一直处在印欧板块碰撞所引起的青藏高原阶段性隆升的挤压构造背景下,经历了两大构造变形期:第一变形期主要发育在古近纪,变形高峰在下干柴沟组上段,第二变形期发育在新近纪—第四纪,变形强度日益加剧。剖面沉积相的变化体现柴西地区经历了水进—静水沉降—水退的过程,平面沉积相演变是沉积中心受构造运动控制的直接结果;受构造演化控制柴西地区以Ⅺ号(油狮断裂)和油北断裂为分界线,由南至北地表形态表现为3种不同样式:柴西南区断裂发育,柴西中部为英雄岭新生造山带,柴西北区主要发育冲断褶皱。柴西地区构造-沉积演化特征是对青藏高原阶隆升的响应,同时记录了青藏高原向北间歇性蔓延生长的过程。on the basis of the analysis of structure and sedimentary evolution of the seismic section in Western Qaidam Basin and combining the basement lithology,faults distribution and history of tectonic movement,we reconstructed the dynamical evolution framework of structure and sedimentation of Western Qaidam Basin during the Cenozoic.Our results suggested that Western Qaidam Basin was under the compression tectonic background of the Tibetan Plateau uplift caused by the collision of India and Eurasia in the Cenozoic and underwent two violent periods of tectonic deformation.The Western Qaidam Basin had undergone two periods of tectonic deformation.The first ocurred in the Paleocene,and reached the peak at the E23;the second was in the Neocene-Quaternary,and the deformation intensified rapidly.The forces transmitted from the south to the north,while the tectonic deformation spread from the west to the east,which indicated that the thrust of the Kunlun fault and the slip of the Altyn Tagh fault were controlled by the collision of the India-Asia Plate and the northward uplift of the Tibetan Plateau.Changes of the sedimentary facies indicatd that Western Qaidam Basin has undergone a process： Inflow-sedimentation-recession and the evolution of sedimentary facies were the result of tectonics.Separated by Youbei fault,in northern region of Western Qaidam Basin there existed thrust folders with the interphase upwarping and depression,generally with closed anticlines and relatively broad synclines,whose axial direction was consistent with the trend of Kunlun Mountains.Between Youbei fault and Ⅺ fault was the palingenetic Yingxiongling orogenic which made obvious elevation difference（about 800m） between the Yingxiongling region and the northern and southern Western Qaidam Basin.The characteristics of structure-sedimentation evolution in Western Qaidam Basin was in response to Tibetan Plateau uplift,and was a good record of intermittent spread of the Tibetan Plateau northward as well.

关 键 词：柴西地区 构造-沉积演化 沉积相 青藏高原隆升 

分 类 号：P542[天文地球—构造地质学]