摘要
笔者通过野外和室内研究认为,吉南老岭群珍珠门组含矿碳酸盐建造其原岩为一套不纯的富含有机碳(质)和陆源碎屑的泥晶灰晶,并央有拉斑玄武质火山碎屑岩。其大地构造环境为大陆裂谷带。成矿物质初始来源于地幔。含矿建造经历了多次变质作用,其中950Ma的动力变质作用对成矿物质再分配起了决定性的作用。铅、锌元素沿走向和垂向分布不均匀,在错草沟—珍珠门一带含矿建造上部为矿化强富集区段,是进一步寻找“荒沟山式”铅-锌矿床的有利地段。整个含矿建造铅、锌丰度高于同类岩石克拉克值的10倍左右,不仅是贮矿层,也是矿源层。
The original rocks of the Proterozoic Zhezhumen ore-bearing carbonate formation are a sequence of impure micrite rich in organic carbon and terrigenous clas- ts, intercalated with tholeiitic pyroclastic rocks. The tectonic environment suggests a continental rift zone. The ore-forming materials were derived from the mantle. The formation had undergone polyphase metamorphism which eventually reached greenschist facies. Among other things, the dynamic metamorphism that occurred 950 Ma ago played a decisive role in the redistribution of ore-forming elements. The distribution of lead and zinc along strike and in a vertical direction is nonhomogeneous. The upper part of the formation in the Cuocaogou-Zhenzhumen area is a strong mineralization sector, where the Pb-Zn abundances are 4 or 5 times higher than the crustal Clarke value, so it is not only a host bed but also a source bed, and worthy of further searching for 'Huangshanggou type' Pb-Zn ore deposits.
出处
《地质论评》
CAS
CSCD
北大核心
1989年第1期30-40,共11页
Geological Review
