Feasibility of using magnetotelluric for sub-basalt imaging at Kachchh, India

Pandey, D.K., MacGregor, L.M., Sinha, M.C. and Singh, S.C. (2008) Feasibility of using magnetotelluric for sub-basalt imaging at Kachchh, India. Applied Geophysics, 5 (1), 74-82. (doi:10.1007/s11770-008-0008-4).

Abstract

Abstract: The magnetotelluric (MT) method has been among the favorite supporting tools for seismic imaging of sub-salt and sub-basalt targets. In this paper we present an example
from Kachchh, India (where basaltic rocks overlie Mesozoic sedimentary rocks) and discuss the feasibility of using MT as an exploration tool in a geological setting such as this. Our results highlight the difference in magnetotelluric response caused by the thin intrabasalt layering. The key issue addressed in this paper is what MT can and cannot provide in such geological settings. First, we compute apparent resistivity and phase response curves using representative resistivity-depth models and borehole data from the study area. Later, we compare these results to assess the plausibility of using MT to image the subvolcanic sediments at Kachchh. Finally we substantiate our discussion through one-dimensional inversion of the field observed MT data from this region that exhibits poor sensitivity of MT for thin basalt layers.

This record has no associated files available for download.

Contributors

Download statistics