Earth Planets Space, Vol. 55 (No. 4), pp. e1-e4, 2003E-LETTER
Mita Rajaram and S. P. Anand
Indian Institute of Geomagnetism, Colaba, Mumbai 400 005, India
(Received December 27, 2003 Revised March 6, 2003 Accepted March 31, 2003)
Aeromagnetic data, covering 600,000 km2 of Central India, have been analysed for the first time to throw light on the various tectonic blocks of the region, ranging in age from the Archean to the present. Existing geotectonic models are based on inadequate data and studies of relatively small regions. From the aeromagnetic data, we use the analytic signal and Euler deconvolution, to elucidate the subsurface structure of the region and redefine the tectonic elements. Contrary to the belief that the Central Indian shear defines the edge of the Central Indian craton, we find that the Sukinda thrust merges with the Tan shear to demarcate the edge of the Bastar and Eastern Ghat blocks by a shear that extends for approximately 1000 km in length. We call this the Main Peninsular shear. Magnetic anomaly data can thus play a crucial role in understanding the tectonic elements of a region with large surface cover.
Key words: Aeromagnetic anomalies, analytic signal, Euler solutions, Peninsular India, Tectonic elements.