Abstract

We have carried out magnetotelluric (MT) study along the 240 km long Chitrakoot - Faizabad profile across the Central Ganga Basin for mapping of the basement structure and extent of the Faizabad Ridge. Broadband MT data have been acquired at 20 sites with inter-station spacing of 8-10 km. The subsurface electrical resistivity image has been obtained by Occam inversion of these data, which reveals very thin sedimentary cover between Chitrakoot and Allahabad. At Allahabad, the basin thickness suddenly increases to more than 2 km and a grabentype structure is seen. Further north, around Amethi the basement comes up to about a km and then increases to more than 2 km around Faizabad. Between Amethi and Faizabad, the thickening of sediments is consistent with the flexure related basin formation. A relatively shallow basement along this profile compared to the results of Manglik et al. (2015) indicates that the Faizabad Ridge is present in this section of the Ganga Basin. More MT data would be required further north to explore the northern extent of the Faizabad Ridge.