内蒙古干旱区赛乌素金矿氧化带及金表生地球化学研究

SUPERGENE GEOCHEMISTRY OF GOLD AND OXIFATION ZONE OF THE SAIN US GOLD DEPOSIT OF THE INNER MONGOLIA ARID CLIMATIC REGION

该矿是内蒙古干旱草原气候区典型的含金硫化物石英脉型矿床。研究表明:自全新世以来该氧化带一直处于干旱气候控制之下;金的表生演化除具有颗粒增大、形态复杂、品位变富和成色增高外,金、银出现双峰富集且基本处同一深度;这与潮湿气候区金、银以“单峰”富集及“上金下银”规律形成鲜明对比。太阳泵是金、银“双峰”富集的主要成因;金的下部富集与较低pH环境有关;伊利石2M_1是金、银上部富集峰主要成因之一。

The Sain Us gold deposit is a typical auriferous sulfide quartz vein deposit in the arid grassland climatic zone of Inner Mongolia The oxidation zone has been controlled by the arid climate since the beginning of Holocene. Gold supergene evolution is characterized by enlargement of gold grains, complication of the gold form, raising of the gold grade and increase of the gold fineness; besides it also shows that gold and silver have two enrichment peaks at the same depth, which is in sharp contrast to the unimodal enrichment of gold and silver and the regularity of occurrence of gold above and silver below in moist climate areas. Sun pumping is the main cause for the bi-modal enrichment of gold and silver. The lower enrichment peak gold is related with the low-pH environment. Illite 2 M1 is one of the main causes for the upper enrichment peak of gold and silver.