青海抗得弄舍重晶石型金多金属矿床成矿地质特征

摘要

抗得弄舍重晶石型金多金属矿床为近几年在东昆仑成矿带东段新发现的典型的热水喷流沉积型金多金属矿床，目前该矿床金矿和铅锌矿的规模均已达大型以上，矿床的发现对东昆仑成矿带东段的找矿带来了新的生机和活力。该矿床以典型的热水沉积岩重晶石含金矿为特点，矿床受地层岩性和同生断裂构造双重控制，矿化与蚀变具有明显的空间分带特征。研究表明硫化物中的铅主要来自地幔，硫来自海水或者海相硫酸盐。指出成矿作用经历了早期喷流沉积成矿期，主要在中低温条件下形成铅锌硫化物矿；晚期热水沉积成矿期，主要在低温条件下形成重晶石和金矿；后期热液及构造活动对矿床有了进一步的富集和改造。%Kangdenongshe barite-type Au polymetallic deposit is a typical hydrothermal sedimentation-exhala-tion Au polymetallic deposit which is discovered in the eastern Kunlun metallogenic zone in recent years.By now the gold deposits and lead-zinc deposits in this deposit are ultra-large scale deposits and their potentials bring vigor and vitality to the prospecting of eastern Kunlun metallogenic zone.With the characteristics of a typical hydrothermal sedimentation barite-type Au deposit,the deposit is controlled simultaneously by strata lithological character and contemporaneous faulted structure,and the mineralization and alteration have obvi-ous characteristics of spatial zoning.The research indicates that the lead in sulfide comes from mantle,while sulfur comes from marine water or marine sulfate.It is argued that the mineralization process of the deposit can be divided into three stages:in early stage,lead and zinc sulfide ores are formed under low-medium tem-perature;in the later hydrothermal sedimentary mineralization stage,barite and gold ores are formed under low temperature;and in the last stage,the deposit is further concentrated and reformed by hydrothermal and tectonic activities.