The application of an integrated geogas prospecting for exploring rare metal deposits in the periphery of the Renli mining area, southern Hunan Province

In this study, six survey lines were deployed in the Huangbaishan survey area in the periphery of the Renli mining area in southern Hunan Province. An integrated geogas prospecting was applied to explore granite pegmatite-type rare metal deposits in the study area. Based on the characteristics of soil X-ray fluorescence and geogas anomalies above the known pegmatite veins in the mining area, this study captured five soil X-ray fluorescence anomaly zones aligning with the formation trend, with the (Nb+Ta+Rb) cumulative value obtained from X-ray fluorescence measurements as the primary prospecting indicator. The Nos. 1~4 anomaly zones exhibit consistent spatial positions with the known pegmatite veins. Accordingly, this study inferred the positions, trends, and lengths of possible pegmatite veins, and a possibility of extension for the known veins based on the anomaly length. The No. 5 anomaly zone discovered on the south side of the survey area, with a length exceeding 1 000 m, serves as a new prospecting target. Geogas prospecting was conducted along the No. 11 survey line in the middle of the No. 4 anomaly zone with a length of over 1 500 m, capturing the geogas anomalies of elements Li, Be, and Nb that reflect the deep mineralization information of pegmatite veins. This confirms that pegmatite veins in the survey area have significant extensions towards the deep part.