新疆维权银多金属矿床地质特征及找矿方向

Geological characteristics and prospecting orientation of Weiquan silver-polymetallic deposit,Xinjiang

文章通过对维权银多金属矿床地质特征的认识,结合矿区矿石、岩石地球化学、稀土元素、微量元素以及硫同位素特征,初步认为该矿床为一个钙矽卡岩型银多金属矿床。区域性韧-脆性大断裂影响带中的华力西晚期花岗岩类岩体与石炭纪含钙质岩系的接触带附近是成矿有利部位;钙矽卡岩带、多金属矿化(孔雀石化、铅锌矿化等)、化探Cu、Pb、Zn、Ag等多金属异常组合、高磁+高重力+高极化+低阻的物探"三高一低"异常组合是最佳找矿标志。区内北部应主要寻找与剪切带成矿作用有关的金矿,南部应主要寻找矽卡岩型铜银多金属矿。

Located in the south of Late Paleozoic Jueluotage island arc belt within the active belt of the north margin of Tarim plate, the Weiquan silver-polymetallic deposit found in 2000 is a middleized silver deposit associated with copper, lead and zinc. The ore bodies occur in the skarnized limestone intercalated with tuff, pebbly sand-stone intercalated with tuff, and limestone intercalated with sandstone. Based on a study of geological and geochemical characteristics, REE, trace elements and sulfur isotopes of ores and rocks, the authors consider that the Weiquan silver-polymetallic deposit is a calcareous skarn type superimposed silver-polymetallic deposit. The favorable ore-forming place is near the contact zone between Late Variscan granitoids and Carboniferous calcium-bearing rocks within the influencing belt of regional tough-brittle large fault. The best prospecting indicators are calcareous skarn belt, polymetallic mineralization, geochemical anomalies of Cu, Pb, Zn, Ag and geophysical anomalies of high magnetism, low resistivity, high polarizability and low gravity. Based on these prospecting criteria, it is held that gold deposits related to shear zones may be found in the north, and skarn type eopper-silver-polymetallic deposits are likely to be discovered in the south.