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Remote Sensing technique with multi-sensor satellite images is found to be a useful tool in delineation of the palaeochannel network in arid to semi-arid regions in India. Principal Component Analysis method with fused images (optical and microwave data) shows a wide N-S trending Sutlej Palaeochannels (SPC) and narrow NE-SW trending palaeochannels in central Punjab. High-resolution Electrical Resistivity Tomography (HERT) survey and litholog data analysis provide good groundwater prospect zone of the palaeochannel. Interpretation of 2D resistivity tomograms with Wenner-Schlumberger method exhibit a thick zone of low resistivity layer (saturated coarse-grained sand) at a depth of 40 m. Integrated geo-tectonic study provides clue that the river migration of Sutlej River from N-S to E-W direction was due to a major tectonic upliftment in the Himalaya. Geochronological data analysis indicates that the avulsed channel of SPC was the main course of old Ghaggar River, linked to the ‘Lost Saraswati River’ in northwest India. [ABSTRACT FROM AUTHOR]

Occurrences of small base metal deposits are reported along the western margin of Aravalli Belt in India. Surface manifestation of one such deposit is found to occur as gossan zone within the host rock of amphibolite in Kalabar area of Rajasthan State. Assessment of this occurrence through drilling technology is a time-consuming exercise, more expensive and requires huge manpower. In the present study, an attempt has been made to rediscover the mineral deposit in Kalabar area using remote sensing and High-resolution Electrical Resistivity Tomography (HERT) techniques. Spectral data analysis with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor shows the characteristic mineral constituents of the gossan zone. 2D electrical resistivity tomograms helped in identifying a narrow vertical zone with low resistivity but high chargeability value up to a depth of 127.9 m. Geospatial analysis of the resistivity data provides the size of the sub-surface deposits. Several exploratory drillings confirm the existence of such deposit up to a depth of 180 m due to presence of highly conductive metallic ore body (Zn, Pb, Cu). Thus, a unique approach is adopted in mineral exploration technology through integrated analysis of surface to sub-surface information. HERT technique is found to be a cost-effective geophysical survey for identifying the geometry and type of shallow base metal deposits. • ASTER spectral data analysis has great potential in characterizing gossan zone. • HERT tomograms show narrow vertical zone of shallow base metal deposit upto 127.9 m. • GIS analysis of resistivity data used for estimation of the geometry of the ore body. • Validation of resistivity tomograms with drilling data and geochemical analysis. [ABSTRACT FROM AUTHOR]