【摘要】 中国东北地区位于亚洲大陆东缘,发育中国乃至地球上最古老的地质记录、多个时代的古洋岩石圈残片和活动陆缘及陆间碰撞岩浆岩带,具有独特的盆山-山脉相间地貌特征,蕴藏着丰富的自然资源。迄今为止,对于该区古生代构造单元如何划分,一直存在截然不同的认识;对于该区中生代以来的构造格架,缺乏系统的论述。本文在简要介绍现今不同山脉和盆地等地理单元地质特征的基础上,基于断裂构造和地貌特征等方面的资料,把该区新生代构造单元划分为大兴安岭、小兴安岭、阴山-燕山和长白山等4个隆起带,海拉尔-锡林浩特、松辽、三江-兴凯湖和下辽河等4个断陷带。基于岩浆活动和沉积盆地分布,结合区域地球动力学背景,提出了该区晚三叠世至中侏罗世、晚侏罗世、早白垩世早期和早白垩世晚期至古新世等不同阶段构造单元划分的初步方案。基于对已有资料的综合研究,对该区古生代构造单元的特征、松辽盆地的基底组成、早古生代和晚古生代华北克拉通北部边界的位置以及古生代洋盆演化及结束时间等重大地质构造问题,进行了初步探讨,提出了阴山-燕山地区在古生代晚期由克拉通转化为陆缘活化造山带;松辽盆地基底具有与周缘造山系相同的地质组成;该区古生代构造单元是陆缘造山带与碰撞造山带的复合而不是地块拼贴;该区在二叠纪晚期遭受了碰撞造山并在华北北缘形成了高耸的近东西走向的碰撞造山带等新认识。根据洋岩石圈残片和古陆缘岩浆岩的分布,把该区古生代构造单元划分为大兴安岭、阴山-燕山、小兴安岭、张广才岭和老爷岭等5个造山系及华北克拉通,简要介绍了不同造山系的地质特征。更多还原

【Abstract】 The Northeast China is located in the eastern margin of the Asian continent,and characterized by occurrence of the oldest geological bodies in the China territory and even on the Earth,ancient oceanic relics with various geological ages from the Late Proterozoic through the Paleozoic to Early Mesozoic and Paleozoic to Mesozoic magmatic complexes with the affinity to the active continental margin and intercontinental collisional belt,unique basin-moutain landform,and abundant natural resources. However,up to now,it has been a hot-debated issue how the Paleozoic tectonic units of the region should be further divided,and lack of systematic discussion and statements on the Mesozoic and Cenozoic tectonic frameworks. In this paper,the geological features of various present geographic units are briefly stated,then,based on new data on fault structure and geomorphology,Cenozoic tectonics of the region is divided into Great Hinggan,Lesser Hinggan,Yinshan-Yanshan and Changbaishan uplifting belts,and Hailaer-Xilinhot,Songliao,Sanjiang-Xingkai lake and Lower Liaohe depressions. The evolution of tectonic frameworks in different stages from the Late TriassicMiddle Jurassic,through the Late Jurassic and Early Cretaceous,to the Late Cretaceous is preliminarily recontructed. Some key tectonic issues,such as features of Paleozoic tectonic units,basement composition of the Songliao basin,the location of the northern boundary of the North China craton in the Early and Late Paleozoic,and evolution and termination of Paleozoic ocean,are preliminarily discussed. Some new ideas are put forward,which include that the Early Paleozoic craton in Yinshan-Yanshan region was changed into the activated continent-marginal orogenic belt in the Late Paleozoic,that geological bodies in the basement of the Songliao basin is the same to those in the adjacent orogenic belts at its two sides,and Paleozoic tectonic units at two sides of the basin may be correlated and connected,that the Paleozoic tectonic units is characterized by accretionary orogenic belts with various geological ages rather than tectonic collage of stable continental blocks as stated in some publications,and that the intense collision took place in the area in the end of the Permian and led to occurrence of west-east extended high mountains in the northern margin of the North China craton. The Paleozoic tectonic units in the area are further divided into 5 orogenic systems named as Great Xingan,Yinshan-Yanshan,Lesser Xingan,Zhangguangcailing,and Laoyeling,respectively,and then,the geological features of those systems are briefly stated.更多还原