A multi-analysis remote-sensing approach for mapping groundwater resources in the karstic Meo Vac Valley, Vietnam

Remote sensing data can be integrated with analyses of topography, structural geology, hydrogeology and geophysics. The integration gives premises for the delineation of zones of potential groundwater resources in strongly fractured and karstified deep aquifers in the uplifted Meo Vac Highland, northern Vietnam. Remote sensing analysis outlines geological faults with hydrogeological significance. These faults are combined with a derived lineament density map, interpreted analysis of surface flow direction and existing hydrogeological data, resulting in indications of groundwater flow direction. An analysis of the SPOT 5 band ratio 4/1, together with indications of surface-flow direction in low terrains, results in a determination of underground cavern passages. The delineated zones of potential groundwater resources are verified by detailed hydrogeological field surveys and geophysical measurements. Remote sensing analysis is shown to effectively contribute to the investigation of groundwater resources for a hydrogeologically complex area.