略论华北地块北缘显生宙三类不同的造山作用

华北地块北缘显生宙发育3种不同类型的造山作用。古生代,华北地块北缘处于古亚洲洋构造域,造山作用属陆缘俯冲-碰撞型,形成以EW向至NEE向为主的褶皱、逆冲推覆构造及韧性剪切带等构造类型。造山机制与古亚洲洋板块向南俯冲-碰撞导致近SN向构造动力的挤压作用密切相关。中生代,华北地块北缘处于西滨太平洋构造域,造山作用以陆内挤压型为主,形成以NE-NNE向与近EW向为主的多期不同方向的褶皱、逆冲断裂、推覆构造、韧性剪切带及局部地区的固态塑性流变构造等构造类型;造山动力以古太平洋(或Izanagi)板块西向俯冲导致NW-NWW向强烈挤压力为主。新生代,华北地块北缘虽仍属西滨太平洋构造域,但造山作用以陆内伸展型为主,裂谷作用与陆内伸展构造居主导地位,褶皱变形微弱,张性-张扭性断裂活动显著,形成现今盆-山构造地貌格局;造山动力以NW-NWW向主张应力为主。造山类型的两次重大转换分别发生于早、中三叠世与晚白垩世。 

THREE DIFFERENT TYPES OF PHANEROZOIC OROGENESIS OF NORTHERN BORDER AREA OF NORTH CHINA CRATON

Three different types of Phanerozoic orogenesis are identified in the northern border area of North China Craton.In the Paleozoic era,the northern border area of North China Craton belonged to the tectonic domain of south peri-Paleozoic ocean and is characterized by subduction-collision orogenesis,leading to the formation of EW-to ENE-trending folds,thrust faults,nappes and ductile shear zones etc.In the Mesozoic era,it was located in the interior of east Eurasia continent and belonged to west peri-Pacific tectonic domain and underwent intracontinental compression orogenesis separated by 6 periods of regional unconformity,more than 5 periods of regional volcanic eruption and plutonism,and strong compressional deformation,producing E-W-,NE-, and NNE-trending folds,thrust faults,nappes,ductile shear zones in the whole area,and structural systems of solid state plastic flow and ring structures in some local areas due to northwestward to westward increasing compression arising mainly from the subduction of the Pacific plate.In the Cenozoic era,it experienced intracontinental extensional orogenesis marked by widespread rifting and extensional faulting with weak folding,giving rise eventually to the present-day tectonogeomorphic features of basins and ranges.This regional extension is believed to be caused by the westward motion of Eurasia plate from the subduction zone.
The transfer of these orogenesis types occurred respectively in the early-middle Triassic and late Cretaceous.