Abstract The telluric electromagnetic sounding in Panxi and Longmenshan areas andtheir neighbouring districts has detected an intracrustal low resistivity layerburied 11-37km below the surface with thickness of 5.5-11km and resistivityof several to tens of ohms, which is likely produced by partially molten graniticsubstances. This layer nearly disappears along the Panxi and Longmenshanmajor structural belt. The thickness of lithosphere in western Sichuan is deter-mined to be 80-143km, and the lithosphere west of the above two major stru-ctural belts obviously becomes thicker. Along the major structures there existdeep-seated high resistivity anomalies, which are apparently consistent with thegravity and magnetic anomalies. lt is thought that these deep-seated high re-sistivity anomalies are probably brought about by mantle substances which flow-ed upward in large quantities at early stage, and that they must have hadintimate relationship with the most important mineralization in this area, thusdeserving further investigation.
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