博格达二叠纪区域伸展背景下的滑塌堆积特征  

Structure features of olistostrome under Permian extension environment in Bogda Mountain Region

作　　者：郭威[1,2] 周鼎武[3] 欧阳征建[4] 周小虎[1] 

机构地区：[1]西北大学地质学系,陕西西安710069 [2]长安大学地球科学与资源学院,陕西西安710054 [3]山东科技大学地球信息科学与工程学院,山东青岛266510 [4]中国石油天然气股份有限公司长庆油田分公司,陕西西安710021

出　　处：《西北大学学报（自然科学版）》2011年第4期658-662,675,共6页Journal of Northwest University（Natural Science Edition）

基　　金：国家重点基础研究发展规划基金资助项目(2001CB409801);国家自然科学基金资助项目(49472135;40472115)

摘　　要：目的探究博格达地区重要转折期的沉积环境和构造特征。方法通过对博格达山南缘地区祁家沟、天池滑塌堆积构造和博格达山北缘白杨河滑塌堆积构造的研究,结合对博格达山及其两侧盆地的侵入岩和火山岩同位素定年和岩石地球化学分析进行研究。结果二叠系沉积时,博格达地区处于区域伸展的裂谷、断陷环境,断陷—裂谷盆地既控制了近源快速的粗碎屑沉积,又控制了板内裂谷环境的基性岩浆侵位和火山喷发、溢流。结论博格达地区早二叠世构造环境发生重大转折,由碰撞造山挤压环境转入造山期后拉张环境。Aim To study the depositional environment and tectonic features at key turning point in Bogda region. Methods The systematical study to structure of olistostromes distributed in areas of Qijiagou and Tianchi in the southern margin of Bagada Mountains and Baiyanghe area in the northern margin of Bogada Mountains, combined with the isotope dating and geochemical analysis on intrusive rocks and volcanic rocks distributed in basins at both sides of Bogda Mountains. Results Bogda region was the environment of regional extension and rift during Permi- an. Rift depression basin controlled not only rapid deposition of coarse detritus, but also intrusion, eruption and o- verflow of basie rocks under inter-plate rift environment. Condusion In early Permian, the tectonic environment of Bogda area changed significantly from the collision orogeny environment to the post-orogenic extensional environment.

关 键 词：博格达 二叠纪 滑塌堆积 构造特征 

分 类 号：P542[天文地球—构造地质学]