江西坳脚下钨矿床地质特征及其成因探讨

Geological Characteristics and Genesis of Tungsten Deposits of Aojiaoxia Tungsten Deposit in Jiangxi

江西坳脚下钨矿地处南岭成矿带之于山钨锡多金属成矿亚带,属夕卡岩型钨矿床。夕卡岩型钨矿体中流体包裹体的均一温度范围在320~500℃;石英脉型钨矿体中的石英矿物的流体包裹体的温度出现3个阶段,其一是350~390℃,其次是220~290℃,频率峰值出现在130~190℃;氧化物矿化阶段的包裹体较少、时间短。研究认为,成矿流体温度和物质组成发生变化是成矿分异的重要原因,钨在流体中以钨酸形式运移,与碳酸盐地层发生反应时温度降低促使其沉淀成矿。

Aojiaoxia tungsten deposit,located in Yushan tungsten-tin polymetallic metallogenic sub-belt of Nanling metallogenic belt,can be classified as skarn type tungsten deposit.The uniform temperature range of fluid inclusions in skarn tungsten ore body is 320~500℃;The temperature of fluid inclusions of Shi Ying minerals in Shi Ying vein tungsten ore body appears in three stages,one is 350~390℃,the other is 220~290℃,and the frequency peak appears in 130~190℃;There are few inclusions and short time in oxide mineralization stage.It is considered that the change of temperature and material composition of ore-forming fluid is an important reason for ore-forming differentiation.Tungsten moves in the form of tungstic acid in the fluid,and the temperature decreases when it reacts with carbonate formation,which promotes its precipitation and mineralization.