Delineation of intra crustal horizon in Eastern Dharwar Craton – An aeromagnetic evidence

• Published in: Journal of Asian earth sciences 2011-01, Vol.40 (2), p.534-541
• Main Authors: Rama Rao, Ch, Kishore, R.K., Pradeep Kumar, V., Butchi Babu, B.
• Format: Article
• Language: English
• Subjects: Eastern Dharwar Craton; Mafic intrusive; Regional aeromagnetic anomaly field; Shear wave velocity
• ISSN: 1367-9120; 1878-5786
• DOI: 10.1016/j.jseaes.2010.10.006

► A prominent crustal layer at a depth of 12 km in the EDC has been delineated by aeromagnetics. ► This crustal layer is associated with perceptible variations in magnetic susceptibility and had discernible shear wave velocity structure. ► The crustal layer is inferred to be the bottom of the upper crust in the part of EDC. A correlative study of two mutually independent geophysical properties like magnetic susceptibility variations and shear wave velocity structure of the crust has been carried out in a part of the Eastern Dharwar Craton of Indian peninsular shield. Analysis of the aeromagnetic anomaly field over an area of 35,000 km 2 comprising the peninsular gneissic basement complex and a part of Cuddapah Basin has resulted in identification of two distinct magnetic horizons: one at a depth of 2 km and the other at a depth of 12 km. Correlation of these results with the inferences made by the inversion of Rayleigh wave phase velocity and other geophysical studies has confirmed the presence of a crustal layer at a depth of 12 km. This horizon has been inferred to be the depth to the lower boundary of the upper crust in this region.