Electrical resistivity imaging of Mohand anticline of Siwalik range: a tectonic appraisal

Abstract

The results of a pilot resistivity sounding experiment undertaken in the Siwalik belt and contiguous Indo-Gangetic Foredeep (IGF) are presented and their lithotectonic significance is discussed akin to the Mohand anticlinal structure. The inferred large lateral resistivity contrast near Ganeshpur delineates the concealed Mohand thrust. The observed resistivity doublet is compatible with the transition in the clast-size and clast-matrix ratio of conglomerate to sandstone. This correspondence provides strong geophysical support to the proposed four stage evolutionary model of the Mohand Siwalik basin on the basis of the facies association and palaeocurrent data. Cyclic pattern of resistivity distribution seen in the Mohand-Sherpur sector of IGF is considered tomanifest episodic character of tectonic events in the Himalayan orogeny.