湖南沃溪金矿区及其外围烃汞叠加晕找矿方法的应用效果

为解决沃溪矿区鱼儿山矿段及其外围的红岩溪—马儿桥矿段深部找矿问题,在区内开展了构造叠加晕和烃汞综合气体测量试验工作。通过对已知矿区鱼儿山矿段的不同地质体、不同标高烃汞组分演化规律和矿体上部土壤形成的地球化学烃汞异常的特征研究,总结土壤地球化学异常场结构、叠加特点及其空间对应关系来开展深部找矿预测,并对外围的红岩溪—马儿桥预测区开展烃汞叠加晕找矿方法的综合研究。经研究发现:红岩溪—马儿桥矿段土壤地球化学场存在两种不同类型叠加场,一类是深源叠加场,Au与烃类组分相关性较好,烃类异常组分齐全,同时Au、Hg异常较好,具有深源成矿热液叠加,深部找矿潜力较大;二类是同生叠加场,Au与烃类组分相关性较差,元素组合相对简单,缺少烃类组分异常,找矿意义不大。烃类异常模式以对偶双峰异常模式为主,在烃类异常双峰之间的低值区发育有较好的烃汞类综合叠加异常,说明深部具有平行盲脉存在。经钻探验证,深源叠加场深部见真厚度8.58 m、平均品位3.55×10^-6的金矿体,而同生叠加场只见有金矿化,故本次研究取得了良好的预测效果。

The application of hydrocarbon and superimposed halo method to the Woxi gold deposit,Hunan Province

In order to solve the problem of deep prospecting in the Yuershanore ore block and its peripheral Hongyanxi-Ma'erqiaooreblock in the Woxi mining area,the authors carried out the tests of structural superimposition halo and hydrocarbon mercury comprehensive gas measurement in this area.Based on the study of the evolution law of hydrocarbon and mercury components in different geological bodies and different elevations and the characteristics of geochemical hydrocarbon and mercury anomalies formed in the upper soil of the orebody,the authors summarized the structure and superposition characteristics of soil geochemical anomaly field as well as the corresponding relationship with space so as to carry out the deep prospecting prediction.In addition,the test of the hydrocarbon and mercury superposition halo was carried out in the Hongyanxi-Ma'erqiao prediction areain the periphery.Based on the comprehensive study of prospecting methods,it is found that there are two different types of superposition fields in the soil geochemical field of Hongyanxi-Maherqiao ore block:one is deep source superposition field,where the correlation between Au and hydrocarbon components is good,the hydrocarbon anomaly components are complete,the Au and Hg anomalies are good,with deep source ore-forming hydrothermal superposition,and the deep prospecting potential is great;the other is syngenetic superposition field,where the correlation between Au and hydrocarbon components is poor,the element combination is relatively simple,and there is no hydrocarbon component anomaly,exhibiting little significance for ore prospecting.The hydrocarbon anomaly mode is dominated by dual bimodal anomaly mode,and there is a good hydrocarbon mercury comprehensive superposition anomaly in the low value area between the two peaks of hydrocarbon anomaly,indicating that there is a parallel blind vein in the depth.Drilling verification shows that the deep source superposition field has a gold orebody with a real thickness of 8.58 m and an average grade of 3.55×10^-6 gold,while the syngenetic superposition field only has gold mineralization.Good prediction results have been achieved.