Effect of coast on magnetotelluric measurements in India

Abstract

Magnetotelluric soundings were carried out at 45 stations along a north-south profile near western coast of India. The magnetotelluric results in the E- and H-polarizatjons showed a significant difference in behaviour. Detailed two-dimensional modelling was carried out to study the effect of the western and eastern coasts of India on magnetotelluric measurements. The effect of the coast on magnetotelluric measurements was seen near the coa"t in both the polarizations. This effect was maximum in the vicinity of the coast in broad frequency range. It is suggested that magnetotelluric measurements in the coastal region of India should be carried out in the E-polarization for a reliable vertical resistivity profile.

Keywords

• Magnetotelluric method
• resistivity structure
• modelling
• India