Abstract:
This is an article in the field of earth sciences. Taka dome and Jianglang dome are located in the southern margin of Songpan-Ganzi block, and their geological characteristics indicate similar composition and metamorphic-deformation characteristics. Liwu, Heiniudong and Zhongsui deposits have been found in Jianglang Dome, while no similar deposits have been found in the same horizon of Taka Dome. To investigate the medium-deep part structure characteristics and mineralization of the Taka Dome, the geophysical electrical parameters and audio magnetotelluric sounding profiles of different strata of different ages were measured to obtain the electrical characteristics of the middle and deep subsurface. The results show that the overall characteristics of the dome are low and medium resistance on both sides, and high resistance in the core is mainly mixed with low resistance. The overall electrical characteristics are consistent with the spatiotemporal law of the dome structure. There are three main low-resistivity anomaly zones in the deep electrical profile, which are inferred to reflect the low-resistivity lithology, fault or structural fracture zone. The three main high-resistivity anomaly belts are inferred to be reflected by the upper member of the Mesoproterozoic Liwu Group (Pt
2l3) with complete medium-high resistivity characteristics in the Taka dome. The above understanding provides geophysical evidence for exploring the medium-deep geological spatial structure of the Taka Dome.