中国浅成低温热液金矿床

浅成低温热液金矿床在中国传统上称为陆相火山岩型金矿床,主要发现在中国东部,后来在北疆地区也有新的发现.根据产出的大地构造背景,它们集中分布在3个带,并分属于3个成矿时期.它们包括:(1)新生代台湾东部岛弧带;(2)晚古生代北疆岛弧带;(3)中生代沿中朝克拉通北界的大陆边缘带;(4)中生代中国东南沿海地区的大陆边缘带.绝大多数矿床是低硫化型的,只有3个是高硫化型的,另有1个是与碱性岩系有关的Au-Te型矿床.除了中国最大的金矿床金瓜石矿床外,迄今为止中国大陆上的浅成低温热液金矿床总的来说只有较小的经济重要性.在中国东部发现的浅成低温热液金矿床的总储量,与区内广泛分布的中生代陆相火山岩十分巨大的体积极不相称.较古老的成矿年龄,中国东部的中生代和北疆的晚古生代,是中国大陆浅成低温热液金矿床的一个鲜明的特点.根据中国的成矿条件和保存条件的分析,以及与美国西部和俄国东部的对比,提出了中国浅成低温热液金矿床成矿潜力的一个初步评估.北疆可能有较大的寻找浅成低温热液金矿床的潜在重要性.

Epithermal gold deposits of China

Epithermal gold deposits have been found mainly in eastern China and recently in the northern Xinjiang Region.They are grouped into four belts based on their tectonic settings and belong to three mineralization episodes.They include:(1)the Cenozoic eastern Taiwan island arc belt;(2)the Late Paleozoic North Xinjiang island arc belt;(3)the Mesozoic continental margin belt along the northern border of the Sino-Korean Craton;and(4)the Mesozoic continental margin belt of SE China coastal area.Most of the reviewed deposits are of low sulfidation type,three are of high sulfidation type,and one is of Au-Te type related to alkaline rock series.Except the Chinkuashih deposit,the largest gold deposit in China,the epithermal gold deposits in general are of less economic importance at present in the mainland of China.The total reserve of epithermal gold deposits discovered in eastern China is not compared with the huge volume of widespread subaerial volcanic rocks of Mesozoic age.Relatively old mineralization age,Mesozoic in eastern China and Late Paleozoic in North Xinjiang,is an apparent feature of epithermal gold deposits in the mainland of China.Based on the analyses of metallogenic condition and preservation in China,and the comparison with western USA and eastern Russia,a preliminary assessment on the potential of epithermal gold deposits of China has been presented.Northern Xinjiang may be potentially significant for finding epithermal gold deposits.