Airborne IP: examples from the Mount Milligan deposit, Canada, and the Amakinskaya kimberlite pipe, Russia
Andrea Viezzoli 1 Vlad Kaminski 1 21 Aarhus Geophysics, ApS, Lollandsgade 52, Aarhus, DK-8000, Denmark.
2 Corresponding author. Email: vlad.kaminski@aarhusgeo.com
Exploration Geophysics 47(4) 269-278 https://doi.org/10.1071/EG16015
Submitted: 7 February 2016 Accepted: 29 May 2016 Published: 8 July 2016
Abstract
There have been multiple occurrences in the literature in the past several years of what has been referred to as the induced polarisation (IP) effect in airborne time domain electromagnetic (TDEM) data. This phenomenon is known to be responsible for incorrect inversion modelling of electrical resistivity, lower interpreted depth of investigation (DOI) and lost information about chargeability of the subsurface and other valuable parameters. Historically, there have been many suggestions to account for the IP effect using the Cole-Cole model. It has been previously demonstrated that the Cole-Cole model can be effective in modelling synthetic TDEM transients. In the current paper we show the possibility of extracting IP information from airborne TDEM data using this same concept, including inverse modelling of chargeability from TDEM data collected by VTEM, with field examples from Canada (Mt Milligan deposit) and Russia (Amakinskaya kimberlite pipe).
Key words: airborne EM, airborne IP, inversion, kimberlite, mineral exploration, modelling, porphyry.
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