老矿区深部资源量预测的地球化学方法——以江西九江城门山铜矿深部铜资源量预测为例

Resources prediction geochemical method in deep area for old orefield—a case study of Chengmenshan copper deposit about copper deep area resources prediction,Jiujiang County,Jiangxi Province,China

老矿区面临着提高资源保障能力和保证矿山长远发展的挑战,对其深部资源量进行预测具有重要的现实意义。以江西城门山铜矿深部铜资源量的预测为例,以富Cu地质体为资源量计算对象,通过函数拟合积分和三维地质体可视化模型,探讨用面金属量积分法和三维地质体块段法进行深部铜资源量预测的原理和具体操作流程。最后尝试利用这2种方法计算第一空间(0～-500m)和预测第二空间(-500～-1000m)的资源量。结果表明:第一空间2种方法均可行,计算结果与传统的储量计算结果十分接近;第二空间资源量预测以三维地质体块段法为宜。当铜矿体边界品位指标分别为0.3%和0.2%时,三维地质体块段法预测深部资源量为57.97×104t和137.58×104t,深部铜资源量主要集中在似层状含Cu黄铁矿中(Ⅰ号矿体)。

In order to improve resource base and guarantee long-term development for old mines, resources predicting and calculating for deep area are imperative under current situation. This paper has researched into Chengmenshan copper （Cu） deposit about Cu deep resources prediction, Firstly certain Cu-enriched geological body has been selected as research target, then by applying fitted function and three-dimension （3D） geological visualization modeling, principles and detailed process by means of integral planar metal quantity and 3D geological body block method are discussed. Two methods has been managed to calculate resources in the range from 0m to -500m （the first space range） and -500m to -1000m （the second space range） in depth respectively. Both of them are feasible for the first space and the results are quite similar compared with the results by traditional method, while 3D block method is preferable for the second space. In conclusion, when the ore cut-off grade index is 0.3% and 0.2% respectively, by using the second method, corre- sponding results are 57.970×10^4t and 137.580×10^4t; besides, deep resources are mainly concentrated in layer-like Cu-enriched pyrite （namely No. I ore body）.