甘肃岗岔—克莫地区蚀变岩特征与找矿预测

岗岔—克莫金矿区位于西秦岭北缘夏河—合作成矿带,具浅成低温热液型矿床特征,初步显示深部可能具有斑岩成矿系统存在。利用短波红外光谱矿物分析技术对岗岔—克莫金矿区蚀变岩特征的研究表明,矿区内发育的蚀变矿物主要有白云母、伊利石、蒙脱石、高岭石、地开石、绿泥石、绿帘石和次生石英等。近矿蚀变类型主要为绢英岩化。矿区内以下家门沟口为中心向外依次发育了中心带(绢英岩化带)、过渡带(泥化带)和外围带(青磐岩化带)。此外,伊利石结晶度以下家门沟口为中心向外具有明显的降低趋势。研究结果指示下家门沟口可能是矿区的热液活动中心。

Altered Rock Characteristics and Gold Prospecting of Gangcha-Kemo Area in Gansu Province

The Gangcha-Kemo gold deposit in the Xiahe-Hezuo region is located on the northern margin of the west Qinling orogen.The deposit is of epithermal type with possible occurrence of deeper porphyry mineralization system.We studied the rock alteration features of the gold deposit with the short-wave infrared spectral(SWIR)mineral analysis technique.The results indicate that local alteration minerals include mainly muscovite,illite,montmorillonite,kaolinite,dickite,chlorite,epidote and quartz.Phyllic alteration is developed mainly around the orebody.The central phyllic zone,transitional argillic zone,and the peripheral propylitic zone are developed successively away from the Xiajiamengoukou area.Besides,illite crystallinity has shown obvious decreasing trend outward from Xiajiamengoukou.This shows that Xiajiamengoukou likely represents the hydrothermal center.