Deep structure characteristics on the western side of the Xuefeng Mountain: New evidence from megnetotelluric (MT) sounding

To understand the deep structure characteristics on the western side of the Xuefeng Mountain and to promote the selection of petroleum exploration strategic areas, the authors comparatively analyzed the faults, folds and the surface and subsurface stratigraphic distribution in the study area by using megnetotelluric(MT) sounding technology in combination with the geological and physical properties in this area to perform qualitative analysis and quantitative calculation. The results show that the subsurface tectonic unit division is basically identical with the surface tectonic unit division on the western side of the Xuefeng Mountain area. It is inferred that the huge thickness of the low resistance layer at the depth of the Xuefeng Mountain uplift region shown on the MT profile is probably the shattered layer caused by the repeated compression process. An investigation of the western part of the MT profile shows that, in the area west of the Xiushan Mountain, the low resistance marker beds is distinct, the thickness of the Sinian-Cambrian strata is great, the tectonic deformation is comparatively weak, and the lateral extension is stable; therefore, this area is considered to be a favorable area for petroleum exploration. This understanding provides important basis for the selection of petroleum exploration strategic areas in the marine lower assemblage.