The genetic mechanisms of the gold deposits in low-temperature mineralization area in southwestern Guizhou

Southwestern Guizhou area is considered highly prospective for gold deposits and an important low-temperature mineralization area on the southwestern margin of the Yangtze platform. It is referred to as a low-temperature mineralization area because it is relatively far from direct magmatic sources, and thus the magmatic exposures are rare in this area. The gold ore bodies are generally hosted in the stratial horizons of different ages, and controlled by deep faults. The mineralization temperatures are less than 300℃. The gold deposits consist dominantly of Carlin-type gold deposits, with subordinate tuff-type ones. These types of gold deposits are identical in the nature of primary ores and mineralization ages of ore deposits, and only quite variable in host horizons. The results of research in the study show that all the gold deposits in varying horizons in this area are obviously constrained by deep faults and deep-seated fluids. The gold deposits have multiphase and polyphyletic origins, and resulted from the reworking of crustal rocks by deep-seated fluids.