摘要
文中研究了矿床的O.S.H.C稳定同位素和稀土元素地球化学特征。指出成矿溶液主要来源于大气降水,部分来自岩浆热液;矿床中的硫一部分来源于地层,另一部分来自柴胡栏子闪长岩株;金以氯的络合物搬运,成矿溶液与围岩的反应是金富集成矿的重要原因。
Chainhulanzi gold ore deposit is of quartz vein—bearing altered rock type Au deposit occurring in Archean metamorphic rocks in the north of Inner Mongolia Anteklise. Marble and graphite—bearing mica—quartz schist are the main host rock with gradational relation to ore bodies which are cut off by chemical analysis. Close relation between the deposit and the diorite stock to north is indicated by REE pattern of the deposit. δ^(34)S of sulfide in the deposit is closely related to the occurrence of sulfide. For veinlet sulfide in quartz vein and skarn is ranged as 7.6—11, 2‰; stratiformed sulfide, —3.1 to 1.5‰; sulfide in sericite schist and graphite—bearing schist, —3.1 to —1.5‰; sulfide in altered rocks and mineralized rocks, 3.1 to 4.3‰. This indicates that S is multiple sourced, some from the Archean metamorpic rock, some from the diorite stock. δ^(18)O value of ore—bearing quartz vein falls in the range of 15.0 to 16.0‰; for ore fluid, 4.0 to 6.0; δD value of quartz inclusion is —93.8, —101.6, —109.7‰ respectively with average of —102‰ which is far from the area of magma fluid and metamorphic fluid and fall in area of meteoric water in plot. In δD—δ^(18)O plot δ^(18)O points are away from meteoric line and drift to right. This may be resulted from O—isotope exchange between meteoric water with very few magma water under low water/rock ratio(0.37—0.50). High salinity of quartz inclusion, (average. 16), low content of sulfide (5％) and most of them are free of gold in ore deposit, intense alteration in wall rocks reveal that gold is transported in Cl—complexes, when interaction between ore fluid and marble and the graphite in the wall rock took place Ph value of ore fluid increases and fo_2 and temperature decrease causing disintegration of Cl—complex and precipitation of gold.
出处
《地质找矿论丛》
CAS
CSCD
1991年第1期67-75,共9页
Contributions to Geology and Mineral Resources Research
