Geoelectric Exploration for Concealed Graphite Zones within Laterite Capping in Karimukal Area, Ernakulam District, Kerala

This paper discusses the Self-Potential, resistivity and electromagnetic prospecting techniques used and the responses obtained over flaky graphite occurrences within laterite capping in Karimukal area, Ernakulam district Kerala. The three main factors controlling these responses are the size and concentration of the conductive body, depth from surface and the country rock.

Detailed Self-Potential (SP) surveys conducted in the area have delineated nine anomalous zones with peak negative values varying from - 145 to -680 mV having width of 30 to 50 m and extending in strike length of 100 to 300 m Graphite has been struck in five of these zones. Results of four more anomalics are yet to be tested Resistivity and Horizontal loop electromagnetic(HLEM) surveys over SP anomaly zones have yielded conductive zones, at shallow depths of 2-9 m Pitting carriedout over these zones revealed graphite occurrences at interpreted depths.