摘要
中生代发生在东北亚地区的蒙古-鄂霍次克造山作用一直是国内外地学界十分关注的大地构造事件.综合利用油气勘探新获取的地震反射、钻井、测井等资料,在海拉尔盆地贝尔凹陷早白垩世断陷层序之下识别出一套卷入强烈挤压变形的构造层.构造解析表明它主要由一条北东东向的逆掩断层及其相关的冲断-褶皱变形系统构成.地层岩性特征和碎屑锆石U-Pb测年结果显示,这是一套沉积于晚侏罗世末期的陆相湖盆碎屑岩建造,区域上应归属上侏罗统塔木兰沟组;结合上覆早白垩世断陷盆地的发育和邻区同期变质核杂岩体隆升剥露时代,提出海拉尔盆地这期冲断-褶皱变形事件发生在早白垩世早期（ca.145~133Ma）,是晚中生代蒙古-鄂霍次克洋闭合后进入强烈陆内造山作用的构造变形记录.
The Mesozoic Mongol-Okhotsk orogeny in Northeast Asia is a significant tectonic event which has attracted interest of many geologists.A tectonic unit involved in strong contractional deformation has been identified under the Early Cretaceous rifting sequences in the Beier depression of the Hailar basin,based on the newly obtained petroleum exploration data including seismic reflection,drilling and well logging.Structural analyses show that the structural system is composed of one major ENE trending overthrust fault and associated thrusting-folding deformations.Lithological and stratigraphic characteristics and dating results of detrital zircon U-Pb show that the strata consist of Late Jurassic terrigenous clastic rock,as a part of the Upper Jurassic Tamulangou Formation in this region.Considering the time of the development of overlying faulted basins and the emplacement of coeval metamorphic core complexes in surrounding area,it is suggested that the thrusting-folding event of the Hailar basin mainly occurred during early stage of the Early Cretaceous（145-133Ma）,which is a key structural record resul-ted from the Mongol-Okhotsk collisional orogeny during the Late Mesozoic.
出处
《地球科学（中国地质大学学报）》
EI
CSCD
北大核心
2016年第7期1141-1155,共15页
Earth Science-Journal of China University of Geosciences
基金
国家自然科学基金项目(Nos.41272231,41330207)
国家重大科技专项课题(No.2011ZX05009-001)
中央高校基本科研业务费专项资金资助项目(No.2016QNA3013)
