华北块体(地台)北缘几个地质问题的探讨及其成矿作用

本文以卫星图象信息为依据,结合野外调研,提出并确定了华北块体北缘存在:块体缝合线,褶皱-逆掩断层带,后孤碰撞带(断裂带),台槽过渡带,岩浆弧,以及燕山-喜山期的NNE向岩浆活动带、断陷带(断陷盆地)等双重构造的新认识。并在此基础上,对华北块体北缘与深成岩浆岩,燕山期岩浆活动带(包括火山岩带)有关的铀矿化作用的独特构造环境及“岩浆”型,断陷带中和面型等主要铀矿床成矿模式和铀成矿带的划分及其划分依据作了研究和探讨。并以铀矿床的实例作为佐证。

DISCUSSION ON SEVERAL GEOLOGICAL PROBLEMS AND URANIUM METALLOGENY ON THE NORTHERN BORDER OF THE NORTHERN CHINA BLOCK(PLATFORM)

According to the information from tne satellite images and and the field investigations the following geological events on the northern border of the Northern China Block are recognized and confirmed, such as suture zones between blocks, folding-reversed fauh zones, back-arc collision zones(faulted zones), transitional zone between platform and geosyncline, magmatic arc and the double structure composed of NNE trending magmatic active belt and fault-depression belts(basins) of Yenshan-Ximalaya age. On these bases the following problems, such as the unique structural environment of uranium mineralization related to abyssal magmatic rocks and Yenshan magmnatic active zone(including volcanic belt) on the northern border of the Northera China Block,the metallogenetic models for uranium deposits of "magmatic type" and neutralized surface type "in fault-depression zone and the classification of uranium metallogenetic belts and the criteria for such classification are studied and discussed. Several uranium deposits are givenvfor illustration.