Intra-Crustal Structure Inferred from Aeromagnetics in a Part of the Eastern Dharwar Craton and its Significance in Kimberlite Exploration

Kimberlites, in addition to being the principal source of industrial and precious diamonds, also serve as windows into the earth's mantle. Therefore, their discovery has academic and economic importance. Power spectral analysis of the aeromagnetic data of a part of the Eastern Dharwar Craton, comprising the western part of the Cuddapah basin and the adjoining crystallines, has brought out upwarping (anticlise) and downwarping (syneclise) of intra-crustal magnetic interface. The known kimberlite diatremes at Wajrakarur and Chigicherla are principally concentrated in zones overlying the domal upwarps of the magnetic interface and these zones perhaps delineate two distinct kimberlite fields. Exploration in such zones (zones overlying upwarp of magnetic interface) is recommended for verifying the validity of the relationship and location of additional kimberlites.