Dépôt numérique
RECHERCHER

The application of rapid potential field methods for the targeting of IOCG mineralisation based on physical property data, Great Bear magmatic zone, Canada.

Hayward, Nathan; Enkin, Randolph; Corriveau, Louise; Montreuil, Jean-François et Kerswill, John (2013). The application of rapid potential field methods for the targeting of IOCG mineralisation based on physical property data, Great Bear magmatic zone, Canada. Journal of Applied Geophysics , vol. 94 . pp. 42-58. DOI: 10.1016/j.jappgeo.2013.03.017.

Ce document n'est pas hébergé sur EspaceINRS.

Résumé

New techniques for the integration of gravity and aeromagnetic data through rock physical property relationships are tested for the rapid location of potential iron oxide-copper-gold (IOCG) exploration targets across the Great Bear magmatic zone (GBMZ). These techniques are based on the recognition of coincident or near-offset magnetic and gravity anomalies associated with IOCG deposits, resulting from their intense and combined iron-oxide and alkali alteration. In the GBMZ, the NICO (Au-Co-Bi-Cu) deposit is an atypical magnetite-group IOCG hosted within an intensely hydrothermally-altered metasedimentary sequence. Prospectivity maps for the NICO area are derived from the integration of high-resolution aeromagnetic and surface gravity data with physical property measurements of magnetic susceptibility and density. Method 1 combines the pseudo-gravity (derived from the aeromagnetic data) and Bouguer gravity data to determine the locations of superimposed high anomalies. Method 2 estimates the apparent susceptibility and density subsurface distribution based on vertical prism models of the magnetic and gravity data. The apparent susceptibility data are transformed to apparent density using physical property relationships. The two apparent density datasets are then combined to determine the location of coincident magnetic and gravity derived anomalies. The results of these methods are supported by, and compared with, similar prospectivity maps generated through weights of evidence techniques. At NICO, the prospectivity maps accurately locate the deposit and nearby occurrences. Despite the lower resolution of the regional gravity data, application of the techniques across the GBMZ is successful at locating mineralised IOCG systems including the magnetite-group systems at Grouard, Fab, DeVries and Cole Lake, the magnetite to hematite-group systems of the Port Radium-Echo Bay district, and has highlighted possible targets for future exploration.

Type de document: Article
Mots-clés libres: gravity; Great Bear; IOCG; magnetic; physical properties; potential field
Centre: Centre Eau Terre Environnement
Date de dépôt: 10 avr. 2018 18:22
Dernière modification: 26 nov. 2020 16:28
URI: https://espace.inrs.ca/id/eprint/4233

Gestion Actions (Identification requise)

Modifier la notice Modifier la notice