Preliminary Geophysical Surveys for Hematite Ore near Veldurthi, Kurnool District, A.P. India.

B. Madhusudan Rao; BVS Murthy; Nagaraju Bhattu; R. Sudarshan

Volume : V, Issue : I, January - 2015

Preliminary Geophysical Surveys for Hematite Ore near Veldurthi, Kurnool District, A.P. India.

B. Madhusudan Rao, Bvs Murthy, Nagaraju Bhattu, R. Sudarshan

Abstract :

The ENE trending Ramallakota– Kalva–Gani fault alignment in the Kumool Basin, extending intoarchaens in the west is a well–known geological feature with occurrence of important minerals. Abutting to this towards south a panoramic structure of a semi–circular basin is positioned about 30kms east of Veldurthi. Geological reports (SatyanarayanaRao.P .1972) reveal occurrences of diamonds in this basin. Recently traces of occurrences of hematite ore isnoticed by villagers in bore holes and stream cuttings. In view of this theauthors have conducted test geophysical surveys employing magnetic andelectrical resistivity methods. Supporting physical property measurements werealso made on samples collected from field. The magnetic field data weremeasured along three traverses, two nearly E– Wand one near N–S. Along traverse three, which is about 320 m long, electrical resistivityprofiling for the entire length and schlumberger soundings at five locationsalong this traverse were conducted. Spectral depths from the analysis ofmagnetic data and the resistivity sounding information helped identifying, thesubsurface layering of the geological successions starting from about twometers depth and up to 20 m depth. Magnetic and electrical resistivity profileshave corroborated well in showing the lateral variations in the lithology underthe soil cover and also possible structural features like faults. The lithological units occurring in the area are red soil on the top, Banganapalle sand stone, conglomerate and hematite ore, below which the local basement could be limestone or quartzites of Cuddapah sequence. The present test geophysical survey has clearly ought out the varying responses of different lithological units in the area and therefore further geophysical surveys in detail can be planned.