中国华北地台二叠纪前陆盆地的发现及其证据

根据受宇地系统场控制的突发性海侵形成的碳酸盐岩－碎屑岩旋回层序界面进行的等时性旋回层序对比，建立了纵穿华北地台晚石炭世＝二叠纪的等时性旋回层序格架，首次发现了华北地台从晚石炭世至二叠纪已经由稳定克拉通盆地转化为具冲断造山楔挤压的前陆盆地，主要证据有：从紫松阶中晚期，隆林阶至栖霞阶，北华北各旋回层序已成为具有前渊造山带物源性质的巨充填层序和反粒序层序（PS6－PS28），在南华北同时限各下超层序的底部均发现具补偿性的深海相泥岩和硅质岩，在南部出现属前陆前隆带的后阶型缓坡碳酸盐岩序；二叠纪沉积盆地的冲断造山带物源性质的普遍存在，似瘤状硅质结核，凝灰岩，凝灰质沉积，以及具有浊积滑塌重力流复理石的沉积共生序列；多期次广泛发育的火山岛弧－孤后火山喷发事件；反极性时和古纬度的变化等，以上证据均支持从早二叠世以来华北板块与西伯利亚－兴蒙褶皱带发生聚敛碰撞形成冲断带和前陆盆地，证明了华北地台在二叠纪已成为具有弧后性质的前陆盆地。

DISCOVERY AND EVIDENCE OF THE FORELAND BASIN IN THE NORTH CHINA PLATFOR MIN THE PERINIAN PERIOD

The symchronous cyclic sequence stratigraphy in the Peri nian was contrasted by the sedimentary sequence boundary of the carbonate rock-silicoclastics rock,resulted in the suddent occurrence of transgression controlled by the Cosmic-Earth system. It is discovered firstly that the North China platform had been transformed from stable Cratonic basin to the sequeezed foreland basin of trust orogenic wedge since Late Carboniferous to Early Perinian. The main evidence is that,①there is the huge thick infilled sequence and inverse graded sequence from mid-late Zisong stage (CS6-PS4 sequence),Nonglin stage and Xixia stage(PS6-PS28) in the northern part of the North China;②and at the same time, the non-compensated marin mudstones and siliceous stones deposited in the infilled sequences downlap bottom of the infilled sequence of the southern area of the North China are discovered;and ③ the backstepping ramp carbonate sequences belong to the forebuldge of appeared in the southern part of the North China. Wide existence of recycle-orogenic trust sources such as nodular-like siliceous concretion,tuff,tuffaceous deposition, the sedimental parragenetic series of slumping,turbidite, gravity flow and flysch in the sedimentary basin during the Perinian period; inmultipe times and wide development of the volcanic island arc and volcanic eruption event, the variation of the reversal of magnetic field and paleolatitude, etc.all indicate that the North China platform, Siberia-Xingmeng fold belt and convergent, collision and trust belt and foreland basin exist; and also prove that the Perinian North China platform is a foreland basin of the backarc property.