南祁连党河南山花岗岩类地球化学及其金铜矿化

南祁连党河南山地区地处南祁连重要成矿带,金铜矿化广布,该矿化与中酸性花岗岩类关系密切.为揭示区域成矿地质背景,查明大地构造的时空演化,并深入研究该地区金铜矿化的成矿规律与控矿因素,对区内主要花岗岩体及其金铜矿化进行了系统的地质地球化学研究.研究表明,区内花岗岩类岩体包括扎子沟岩体、鸡叫沟岩体及贾公台岩体.综合岩相学、岩石化学及微量稀土元素地球化学特征,区内3个岩体均形成于I型活动陆缘环境,为中南祁连造山带加里东期构造岩浆活动的产物.扎子沟岩体与该区金铜矿化不构成物源关系,但其岩浆期后热水溶液可造成火山岩系金、铜组分活化迁移,并在有利构造场所富集成矿,鸡叫沟岩体和贾公台岩体分别是黑刺沟金矿和贾公台金矿的控矿母岩.

GRANITOID GEOCHEMISTRY AND GOLD - COPPER MINERALIZATION IN THE DANGHENANSHAN AREA, SOUTHERN QILIAN MOUNTAINS

Danghenanshan area in the southern Qilian Mountains is an important metallogenic belt.Gold and copper mineralization is common in the area,which is related with intermediate-acidic granitoids.In order to reveal the regional geologic setting of metallogenesis,find out the features of geotectonic evolvement,and study the metallogenic regularity and gold-copper ore-controlling factors,systematic geologic and geochemical studies of main granitic plutons as well as gold-copper mineralization have been made.It is concluded that granitoids include Zhazigou,Jijiaogou and Jiagongtai plutons in the area,and the granitoid characteristics of lithofacies,petrochemistry,trace element and REE geochemistry indicate that these three plutons are all I-type granitoids,formed in an active continental margin,and the results of tectonic movement and magmatism in the middle-south Qilian Mountains during Caledonian.Zhazigou pluton doesn't provide materials for gold and copper mineralization in the area,but its post-magmatic hydrothermal fluids can activate Cu and Au elements in volcanic rocks,and cause them to enrich in the advantageous place.Jijiaogou and Jiagongtai plutons are the ore-controlling rocks of Heicigou and Jiagongtai gold deposits respectively.