Wood textures in Jinman copper deposit in western Yunnan and their geneticimplications

Jinman vein copper deposit in western Yunnan occurs in a salt-bearing red e lastic rock formation composed of sandstone, siltstone and shale. Wood text ure is considerably developed in the ores. The metallic minerals making up the wood textures mainly include pyrite, chalcopyrite and bornite, Studies on the samples and examination of their micrographs and electron micrograph s have confirmed that they belong to xenoxylon, reflecting that the ore-hos ting rock series is the product of sedimentation in the terrestrial environ ment. Organic geochemistry and sulfur and carbon isotopic composition data indicate that the formation of the deposit is substantially related with un derground hot brines and biological processes.