云南维西山加铜矿床地质特征及成因浅析

Geology and Genesis Analysis of Shanjia Copper Deposit in Weixi, Yunnan

维西山加铜矿位于三江成矿带,Ⅴ—Ⅶ号矿体均赋存于花开左组碎屑岩夹碳酸盐岩中,位于近南北向张性断层F3破碎带中;Ⅷ号矿体赋存于景星组碎屑岩中,位于北西向张性断层F5破碎带中。矿体呈脉状、透镜状产出,严格受断裂构造的控制。矿床中矿质在沉积成岩时已初步富集,后经地下热卤水对富含铜的沉积层进行溶滤和搬运,在有利的地层和构造薄弱部位进行充填、交代而形成矿床。此外,用爆裂法和均匀法对孔雀石、辉铜矿进行测温,其成矿温度在175~250℃之间,应属中低温热液矿床。

Weixi Shanjia copper ore is located in Sanjiang metallogenic belt. Ⅴ—Ⅶ ore are all existed in the clastic rocks and carbonate rocks of Huakaizuo group in nearly SN-trending extension fault F3 crushed zone. Ⅷ ore is existed in the clastic rocks of Jingxing group in NW-trending extension fault F3 crushed zone. The ore body is in veined and lentoid shape and is Strictly controlled by fracture structure. The minerals in the ore had been gathered preliminarily in sediment and diagenesis. Later, the settled layer rich in copper was leached and handled by underground geothermal brine, and then formed ore after filling and metasomatism. Besides, burst and uniform method are used to test the temperature of malachite and molybdenite, whose mineralization temperature is between 175~250℃, belonging to medium low temperature thermal liquid ore deposit.