甘肃省成县李家沟铅锌矿床成矿特征及成因机制

李家沟铅锌矿床产于中泥盆统安家岔组厂坝层中级变质的碎屑岩加碳酸盐岩建造中。矿体呈层状、似层状，与围岩整合产出。矿石具条带状、块状构造。地层、岩石、岩相古地理和相变带是主要控矿因素。矿石硫化物它集重破，铅同位素基本上属较均匀单阶段演化的正常铅。矿体方解石与围岩方解石的氧、碳同位素值相近。原始成矿溶液为高盐度的氯化物型热卤水。该矿床应属地下热卤水喷益一沉积变质层状铅锌矿床。

GEOLOGY AND METALLOGENIC MECHANISM OF THE LIJIAGOU Pb-Zn DEPOSIT IN CHENGXIAN COUNTY, GANSU PROVINCE

The Lijiagou Pb - Zn deposit is hosted in mediate - graded metanorphosed clastic rocks and carbonate formation of AnjiachaFormation of Middle Devonian.The orebodies occur in laye or quasi - layer confermable to host.Ores are characterized by massive andbanded structures. The strata rocks, lithofacies and paleogeography and facies transition are the main ore - controlling factos.Heavy sulphuris enriched in sulfides; The Pb isotope belongs to normal lead with single stage evolution characteristics.The O and C isotopes of calcite fromores is similar to that from host rocks.The primary ore - forming fluid is chloride brine with high salinity. This deposit is of origin of brineexhalation - sedimentation - jmetamorphic strata- form deposit.