太行山东麓断裂带板内构造地貌反转与机制

The intraplate morphotectonic inversion along the Eastern Taihang Mountain Fault Zone,North China and its mechanism

华北克拉通前寒武纪基底可划分为东部地块、中部带和西部地块。中生代以来,华北克拉通发生减薄破坏,其破坏中心位于东部地块,而西部地块与中部带基本保持完整,其过渡带就是太行山东侧。太行山地区近乎平行发育着两条重要的断裂:太行山大断裂和太行山山前断裂,统称为太行山东麓断裂带。通过研究发现,太行山山前断裂是继承早前寒武纪构造带形成的断裂,控制着太行山与东部地块前寒武纪基底的差异,古新世以来发生板内构造地貌的负反转,构成渤海湾盆地的西界断裂。太行山大断裂则在燕山期时为重要的逆冲断裂,对太行山的隆起起着重要作用;中新世以来,伴随着山西地堑系的形成,太行山大断裂发生构造负反转,控制着一系列山间地堑的发育。新生代以来,该区构造演化特征整体表现为向西构造迁移的特点,是区域走滑伸展背景下的一种新的板内盆山关系。

The North China Craton can be divided into the Western and Eastern Blocks separated by the Trans-North China Orogen.Since the Mesozoic,the North China Craton underwent thinning and destruction.The destruction center is located in the Eastern Block,whereas the Western Block and the north-trending Trans-North China Orogen remained their integrity,and the transition zone between them is the eastern Taihang Mountains.Two subparallel important faults developed in the Taihang Mountain region,called the Taihang Mountain Large Fault and the Eastern Taihang Mountain Fault respectively,as the major faults of the Eastern Taihang Mountain Fault Belt.Previous studies revealed that the Eastern Taihang Mountain Fault is inherited from Precambrian tectonic belts controlling the differences of Precambrian crystalline basements between the Eastern Block and the Taihang Mountain Region.Since the Palaeocene,the Eastern Taihang Mountain Fault developed into negative morphotectonic inversion as a normal fault in the western margin of the Bohai Bay Basin.However,the Taihang Mountain Large Fault existed in the Yanshanian as a major thrust,and played an important role in the uplift of the Taihang Mountains.During the middle Miocene,along with the formation of the Shanxi graben system,the Taihang Mountain Large Fault underwent a negative structural inversion and controlled the development of a series of intermontane grabens.Since the Cenozoic,the tectonic migration in this region as a whole jumped toward the west,developing under regional strike-slipping and extension a new intraplate mountain-basin relationship.