北山成矿带金矿成矿规律与远景

METALLOGENIC REGULARITY AND PROSPECT OF GOLD DEPOSITS OF BEISHAN MINERALIZATION BELT

位于新(疆)甘(肃)交界的北山成矿带属于北山古生代裂谷—造山带,呈NEE—EW—NWW向展布.在该裂谷带及其两侧基底岩系中分布着不同类型金矿床(点),根据矿床成因可分为:热液石英脉型、火山-次火山热液型、变质热液层控型、构造蚀变岩型及矽卡岩型金矿床.控矿因素:韧性、韧-脆性断裂,火山岩-碎屑岩地层,华力西、加里东期中酸性、中基性岩浆岩,成矿时代为华力西晚期、印支期和燕山期,与该期构造同或准同步.据此认为:坡子泉—明锡山、金窝子—照壁山、拾金坡—金厂沟、方山口—营毛沱、老硐沟—洗肠井、老金厂—金场沟、白墩子—石板墩、小西弓—金庙沟井和小宛南山—万字沟等找矿远景区.

The Beishan mineralization belt at the boundary between Gansu and Xinjiang goes along NEE-EW-NWW trending Beishan rift-orogeny. Various types of gold deposits are present in the basement rocks within the rift zone and along both sides. The genetic types of gold deposits include hydrothermal quartz-vein type, volcanic-subvolcanic hydrothermal type, metamorphosed hydrothermal stratotype, structurally-altered rock type and skarn type. The gold deposits are controlled by ductile, ductile-brittle faults, volcanic-clastic strata, Variscan and Calodonian intermediate-acidic, intermediate-basic magatic rocks. The mineralization is of late Variscan, Indonian and Yanshanian ages which synchronize or sub-synchronize with structures. Accordingly, the following areas are thought to be prospect areas, including Poziquan-Minxishan, Jinwozi-Zhaobishan, Shijinpo-Jinchanggou, Fangshankou-Yinmaotuo, Laotonggou-Xichangjin, Laojinchang-Jinchanggou, Baidunzi-Shibandun, Xiaoxigong-Jinmiaogoujin and Xiaowannanshan-Wanzigou.