摘要
上宫金矿赋存在中元古界熊耳群安山岩和玄武岩中，矿体受断裂破碎带控制。含矿热液在迁移过程中，与围岩发生了强烈的流体－岩石反应，造成Ａｕ、Ａｇ、Ａｓ、Ｓｂ等成矿及其相关微量元素和Ａｌ２Ｏ３、ＴｉＯ２、Ｎａ２Ｏ等常量元素含量增加，稀土元素及其总量急剧减少。流体－岩石反应第一阶段发生的温度和压力条件为３６５℃～３００℃和２８５～２００ＭＰａ，而大量金沉淀成矿时的温度和压力范围则分别为３２５℃～２４０℃和１６０～１００ＭＰａ。成矿热液类型及其演化比较简单，从初始的低盐度（９．５％～６．３％ＮａＣｌ）、ＸＣＯ２为０．１８～０．２４的含ＣＯ２流体演化为低盐度（５．９％～１．６％ＮａＣｌ）的水溶液流体。
The Shanggong gold deposit is contained within a ductile shear zone in
weak metamorphosed rocks of the middle Proterozoic Xionger Group. The ores occur as
veins or as lenticular bodies within altered basaltic andesitic host rocks. During fluid rock
interaction, the ore forming components were not equally mobile. Inner alteration zones are
characterized by additions in components such as Au、Ag、As、Sb and Al 2O 3、TiO 2、Na
2O, and by decreasing in REE. Fluid inclusion data suggest that temperature and pressure
during first stage of fluid rock interactions were 365℃ ￣ 300℃ and 285MPa ￣ 200MPa, and
325℃ ￣ 240℃ and 160MPa ￣ 100MPa in gold deposition stage. Primary fluids were
associated with a homogeneous H 2O CO 2 NaCl fluid containing 0 18 ￣ 0 24 X CO2 and
9 5% ￣ 6 3% NaCl, and changed to aqueous fluid with 5 9% ￣ 1 6% NaCl during gold
mineralizing stage. Fluid rock interactions were main reason for gold deposition.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
1998年第4期529-541,共13页
Acta Petrologica Sinica
基金
国家自然科学基金
关键词
金矿床
成矿过程
构造蚀变岩
流体-岩体反应
Gold deposit
Structure controlled alteration rocks
Fluid inclusion
Fluid rock
interaction
Ore genesis
Shanggong
