Geophysical modeling of time domain electromagnetic and potential field data in the Equity silver polymetallic deposit: British Columbia, Canada

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Abstract

The Equity silver mine, located 38 km southeast of Houston, British Columbia, Canada, is a volcanic-hosted sulfide deposit associated with intrusive activity. The original prospect (locally referred to as the Sam Goosly prospect) was a new discovery found as a result of regional silt geochemical surveys conducted by Kennco Exploration (Western) Ltd in 1967. Further investigations confirmed the existence of two distinct mineralized zones, the Main zone and the Southern Tail zone. The purpose of this research is to provide useful three-dimensional (3D) physical property products that can directly be employed in locating and identifying feeder areas related to polymetallic mineralization in the Equity silver area in central British Columbia, Canada. In this research work, airborne gravity, magnetic and electromagnetic data from the study area were used. The data inversions were performed using the UBC-GIF GRAV3D, MAG3D and EM Flow, suite of algorithms for the gravity, magnetic, and AEM data respectively. The products were 3D inversion models of density contrast, magnetic susceptibility, and electrical conductivity, and integrated products combining the individual physical property models. For the study area, surface geological observations, 3D inversion results of airborne gravity, magnetic and electromagnetic data were integrated to build a 3D geological model to identify mineral targets. Finally, a prospect zone was discovered with higher density contrast and higher electrical conductivity property compared to the surrounding environment. The thickness of this part was found to be between 30 and 60 meters and extended to a depth of about 200 meters from the surface.

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References

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Volume 8, Issue 3
July 1401
Pages 213-228

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