STUDIES OF ORGANISM ON MINERALIZED-ALTERATION ZONES OF Au-Sb-W DEPOSIT, WESTERN WOXI, HUNAN, CHINA

Based on the geological characteritics of the deposit, some natures of organism in ore wall rocks have been studied. With the action of hydrothermal solution, the main mineral-forming components Au⁺ and Au³⁺ are reduced by organism, and the organism turns into CO₂. Unaltered wall rocks, altered wall rocks of W mineralization and altered wall rocks of Au and/or Sb mineralizations have different forms of pyrolytic chromatogram, pyrolytic parameters and maturities of organism. In unaltered rocks, the maximun pyrolytic temperature, productivity index, degradating potentiality and hydrocarbon index of the organic matter are low, and the organic maturity is the lowest of the all rocks (in unmature region). The procession of the release of pyrolytic hydrocarbon is a sudden change;In W altered rocks,the organ ic carbon content is high, the type index is low, and the organic maturity is high (in the oil region). There are two times of unsudden release of pyrolytic hydrocarbon in the rock; In Au and/or Sb altered rocks, the maximum pyrolytic temperature, soluble content of hydrocarbon, yield index, effective carbon, degradation potentiality and hydrocarbon index are high, and the organic maturity is the highest (in the gas region). The pyrolytic hydrocarbon is, released unsuddenly.