湘西沃溪金锑钨矿床矿化蚀变带特征研究

CHARACTERISTICS OF MINERALIZED ALTERATION ZONE IN WOXI Au—Sb—W DEPOSIT WESTERN HUNAN

本文结合沃溪金锑钨矿床地质背景,从矿化蚀变类型、矿化蚀变分带、地球化学、稀土元素、有机质,穆斯堡尔效应等几个方面详细的对矿化蚀变作用进行研究,并提出了找矿依据。

Woxi Au-Sb-W deposit is a large scale polymetallic deposit. Its orebodies fill in the interlayer fractures. Mineralization tends to be a little stronger with the increase in depth of the deposit. Alteration of different types are widely developed around orebodies. Decolourization developed along both sides of the veins, and all the orebodies are found within the decoloured shale zone. Muscovitization and silicification become stronger with the intensification of Au, Sb and/or W mineralization. The strength of pyritization is positively correlated with Au mineralization. Chloritization and carbonatization developed in the interlayer fractures indicate the weakening of mineralization or the thinning out of veins. The alteration in the deposit can be divided macroscopically into two zones: decoloured and undecoloured zones; and microscopically into Fe-Ti oxides, Mus+Q, Q, Mus+Py. Voin. Mus+Py, Q+Py. Mus+Chl, Chl+Mus+Q, Fe-Ti oxides from hanging wall to bottomwall. Different types of alteration are of different geochemical features. The tungstern-related alteration cause the rare earth elements migrate out from wall rock; while the gold and antimonyrelated alterations introduce some rare earth elements into the wall rocka. The alterated rocks bear lower organic matter than the unalterated ones.Different types of alteration can be used as an aid to mineral exploration and prospection.