The Application of GATEM in Water-Conducting Channels Survey in High Plateau Area

Abstract Characterizing complex water-conducting channels in high plateau karst regions is critical for mitigating engineering risks associated with fragile geological structures. Conventional geophysical surveys are hindered by this challenging environment: ground-based methods are limited by steep terrain, while airborne electromagnetics (AEM) often lack the required investigation depth and can be cost-prohibitive. Here, we demonstrate the efficacy of the ground-airborne transient electromagnetic (GATEM) method for mapping water-conducting channels within a geologically complex karst zone on the eastern margin of the Qinghai-Xizang Plateau. GATEM synergizes a high-power, ground-based electric dipole source for deep penetration with a drone-borne magnetic field receiver for rapid, terrain-independent data acquisition. A comprehensive processing workflow—including noise attenuation, full-field apparent resistivity imaging, terrain correction, and time-to-depth conversion—was implemented to generate robust subsurface models. The resulting models reveal coherent, low-resistivity anomalies that spatially correlate with known fault zones and stratigraphic boundaries. These features are interpreted as likely preferential groundwater pathways, offering critical insights for infrastructure planning and geological hazard mitigation. Our findings establish GATEM as a cost-effective, high-resolution geophysical tool for hydrogeological characterization in challenging plateau environments.