青海祁连两类火山成因硫化物矿化蚀变带地球化学特征及找矿标志

GEOCHEMICAL CHARACTERISTICS AND PROSPECTING INDICATORS IN TWO TYPES OF VOLCANOGENIC SULFIDE MINERALIZATION ALTERATION ZONES IN QILIAN COUNTY, QINGHAI PROVINCE

研究区发育火山成因块状黄铁矿矿床和铅锌铜多金属硫化物矿床及其相应的两类矿化蚀变带．黄铁矿矿化蚀变带以亏损Ｐｂ，Ｚｎ，Ｃｕ，Ａｇ，Ｓｒ，Ｂａ，Ｍｎ及Ｋ，Ｎａ，Ｍｇ等元素，且多为负异常，元素无明显共生组合规律为特点；多金属矿化蚀变带则以富集多金属元素及伴生元素，富Ｋ，Ｍｇ，贫Ｎａ为特征，而且多元素共生组合好，异常强度高而宽度窄，下盘晕强于上盘晕．同时，总结了两类矿化蚀变带地球化学找矿标志。

Series of volcanogenic massive pyrite and Pb_Zn_Cu multi_metallic sulfide deposits and associated alteration zones exist in the research area. The pyrite alteration zone is deficient in Pb, Zn, Cu, Ag, Sr, Ba, Mn as well as K, Na, Mg, usually expressed as negative anomalies and lack of regular associations. The multi_metallic mineralization alteration zones are characterized by high concentrations of ore elements and associated elements, rich in K and Mg, poor in Na with a full range of element association, intensive anomalies and narrow width. The footwall haloes are more intensive than the hanging haloes. Geochemical prospecting indicators for the two types of mineralized alteration zones are formulated, and evaluation of ore_bearing potential of these major alteration zones in the study area is given.