鄂西-湘西北地区铅锌矿矿源层对铅锌矿床产出定位的制约

自鄂西至湘西北一线,自北至南铅锌矿的产出层位逐渐抬高。通过对该区矿源层的分析研究发现,矿源层层位控制了铅锌矿的产出层位,北部鄂西地区矿源层为震旦系下统陡山沱组含泥碳质碎屑岩,南部湘西地区矿源层为寒武系下统牛蹄塘组含泥碳质碎屑岩。以地层不整合界面和盆地演化的充填系列为成矿单元,下部碎屑岩地层中的铅锌矿源层制约了上部碳酸岩地层中的铅锌矿的产出定位,矿床就位是热液、矿源层、导矿构造、储矿空间、屏蔽层等多因藕合、临界转换的结果,其成因为盆源热液矿床。

Constraints of Lead-Zinc Source Bed to Lead-Zinc Deposits in Western Hubei to Northwestern Hunan

From western Hubei to northwestern Hunan,the product position of lead-zinc ore increases from north to south.It is found that the source bed position controls the product position of lead-zinc deposit,as it is argillaceous carbonaceous clastic rock in lower Sinian System Doushantuo Formation in the north of western Hubei.In the south of western Hunan,the source bed could be argillaceous carbonaceous clastic rock in lower Cambrain System Niutitang Formation.When the stratigraphic unconformity interface and filling system of basin are the ore forming units,the occurrence and location of lead-zinc ore in carbonatite stratum upside are limited by the source bed of lead-zinc ore in clastic rock stratum underpart.The deposit position is the result of coupling and critical transformation by hydrotherm,source bed,report mine construction,storage space and shielding layer.The lead-zinc deposit is classified as the basin-derived hydrothermal deposit.