热液沸腾作用与金矿化的关系及其找矿意义

RELATIONS BETWEEN THE HYDROTHERMAL BOILING ACTION AND GOLD MINERALIZATION AND THEIR SIGNIFICANCES

在热液沸腾过程中,pH值升高,CO_2、H_2S等气体逸失,温度下降。金常常富集在沸腾面附近,故沸腾面的圈定对于金矿的找矿勘探及预测有重要意义。与沸腾作用有关的金矿床,除典型的浅成低温热泉型金矿外,一些与碱性岩有关的金矿、隐爆角砾岩型金矿、斑岩型金矿及一些中—低温岩浆热液型金矿中也发现有沸腾矿物包裹体存在,说明热液沸腾作用在金矿形成过程中很可能是一种较普遍的成矿作用。对热液沸腾作用的研究将有助于金的沉淀机制及成矿预测研究工作。

pH increases and CO2, H2S and other gases diffuse as the temperature is decreasing because of the boiling. Gold deposition occurs in the vicinity of the boiling surface. Therefore, the boiling surface has an important significance in prospecting. The gold deposits related to the boiling action contain several types connected with alkalic rock, explosion breccia rock and porphyry besides the typical hot-spring and epithermal gold deposits. Moreover, the boiling inclusions can be found in epi-mesothermal gold deposits related to magmatite. All of these findings indicate that the boiling action may be a wide ore-forming event in the forma- tion of gold deposits. The study on it will benefit the research work on gold deposition mechanism and ore-prospecting.