White Rock Minerals Ltd (ASX:WRM) has processed and modelled four lines of controlled-source audio-frequency magnetotellurics geophysics that were surveyed at the Last Chance gold target within the wider Red Mountain Project in Alaska during the 2020 field season.
The CSAMT geophysics survey was conducted by Zonge International Inc, one of the world’s leading geophysical contractors.
These initial four lines of CSAMT were surveyed to map the variability of rock resistivity across the core area of the large Last Chance target, to identify rock resistivity characteristics that could assist in interpreting the upper levels of the gold system and determine whether resistivity could be useful in targeting structure and alteration associated with mineralisation.
The significant subsurface structural data obtained from this work will prove useful for White Rock in planning follow-up drill targeting during the 2021 field season.
Method used to identify shallow targets
The CSAMT method can be used to identify targets at shallow levels where surface talus conceals the underlying geology and can also be used at depth where geological observations from reconnaissance mapping and drilling.
Surface geochemical results suggest that the Last Chance gold target lies within the upper brittle domain of a large orogenic and or intrusive related gold system (IRGS).
Survey to form important data set
This CSAMT resistivity survey will form an important data set alongside the other data collected during the company’s very first 2020 field season at Last Chance.
Together, the CSAMT resistivity data will be integrated with the airborne magnetic and radiometric data, the satellite multispectral data, reconnaissance geological mapping, detailed surface geochemistry and data from drill core including detailed geology, structure and multi-element geochemistry.
Once integrated, these quality datasets will be used to generate a 3D model of the geology, rock alteration and structure and provide White Rock with a quality interpretation of this overall gold system, its regional setting and a range of follow-up targets for the 2021 field season.