3D geological modeling and stratified skarn target prediction in the Jiama deposit, Tibet

The Jiama deposit in Tibet is a very typical polymetallic deposit in the Gangdise metallogenic belt.Through theoretical prediction and research, it is believed that concealed porphyry-skarn ore bodies are developed in the deep part of the ore-concentrated area.However, the exploration model based on the borehole coverage of the mining area has a low degree of prediction of the potential target in the peripheral area.Based on the density, magnetic properties, resistivity, and polarizability data of 45 borehole cores in the Jiama deposit, the three-dimensional magnetotelluric sounding data covering the Jiama deposit and its periphery were analyzed.Based on GOCAD software, the stratum lithology-geophysical three-dimensional visualization integrated model of the Jiama deposit was constructed through discrete smooth interpolation and stochastic simulation algorithms.Combined with the results of 2D geological interpretation of 11 magnetotelluric(MT) profiles, the development characteristics of 3D skarn bodies below 3000 m were finely depicted and verified with the Jiama Scientific Deep Drill JMKZ-1 which was not involved in the modeling.The results show a consistency agreement.Besides, based on the skarn metallogenic model, combined with the analysis of the electrical parameters of the Jiama deposit and adjacent areas, as well as the electrical characteristics of the three-dimensional skarn, the favorable target area of stratified skarn in Jiama deposit is predicted.The results can provide a demonstration of 3D modeling technology for the evaluation of deep resource potential and reserves increasing in the mining area.