皖南浙西晚震旦世至早寒武世硅岩物源与环境类型初探

通过野外与室内的研究工作 ,认为皖南浙西地区晚震旦纪至早寒武纪的硅岩是复合成因的产物 ,其物源类型比较复杂 ,包括热水来源、生物来源及陆源输入 ,但以热水来源的SiO2 为主。产出的环境属于近洋脊与大陆边缘环境之间的过渡带。岩石学及地球化学的研究都证明了上述观点。

ORIGINS AND ENVIRONMENT TYPES OF CHERT IN WESTERN ZHEJIANG AND SOUTHERN ANHUI FROM LATE SINIAN TO EARLY CAMBRIAN

From Late Sinian to Early Cambrian, the western Zhejiang and southern Anhui belonged to southeastern margin of the Yangtze Platform. The chert was formed in rift fault basin between Yangtze continental and Huaxia continental.After through the fieldwork and laboratory research,the authors found that the cherts of western Zhejiang and southern Anhui are multiple genesis; their material source is complicated, including hydrothermal input, biogenic input and continental input. The forming environment belongs to near ridge and continental margin and the transform environment between them. The petrology and geochemistry studies proved the above opinions. In this paper ,the authors discuss the cause and origin of the cherts according to the new discriminating diagram to recognize various types of environment of the cherts.