VTEM airborne EM, aeromagnetic and gamma-ray spectrometric data over the Cerro Quema high sulphidation epithermal gold deposits, Panama*
Karl Kwan 1 Alexander Prikhodko 1 Jean M. Legault 1 3 Geoffrey C. Plastow 1 John Kapetas 2 Michael Druecker 2
+ Author Affiliations
- Author Affiliations
1 Geotech Ltd, 245 Industrial Parkway North, Aurora, Ontario, Canada L4G4C4.
2 Pershimco Resources Inc., 11 Perreault Street East, Rouyn-Noranda, Quebec, Canada J9X3C1.
3 Corresponding author. Email: jean@geotech.ca
Exploration Geophysics 47(3) 179-190 https://doi.org/10.1071/EG15080
Submitted: 26 August 2015 Accepted: 8 February 2016 Published: 10 March 2016
Abstract
In March 2012, a helicopter-borne versatile time-domain electromagnetic (VTEM), magnetic and radiometric survey was flown over the Cerro Quema high sulphidation (HS) epithermal gold deposits and the surrounding area. The Cerro Quema deposits are located in the Azuero Peninsula, Panama, approximately 8 km east of Güerita. The gold mineralisation is associated with clay-pyrite alterations topped by an acid-leached resistive cap, and the principal ores are pyrite-rich sulphides located within mineralised vuggy silica rocks.
The geophysical data over the Cerro Quema deposits have been analysed. The electromagnetic (EM) responses over the deposits are characterised by resistivity highs and chargeability lows, surrounded by resistivity lows and chargeability highs. Radiometric Th/K ratio highs and magnetic susceptibility lows are observed over the deposits. These geophysical signatures over the Cerro Quema deposits are characteristic responses from HS epithermal gold deposits.
The success of the VTEM survey points to the applicability of the regional helicopter electromagnetic, magnetic and gamma-ray spectrometry (EM-Mag-Spec) surveys for the exploration of similar HS epithermal gold deposits to depths < 500 m in weathered terrains.
Key words: AIIP, airborne EM, epithermal, gold, high sulphidation, magnetics, spectrometry (radiometrics).
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