JOHANNESBURG (miningweekly.com) – Prospectair Geosurveys of Gatineau, Québec, has completed about 1 977 linear kilometres, representing 50%, of a detailed helicopter-borne magnetic (MAG) and time-domain electromagnetic (TDEM) survey of TSX -V-listed Visible Gold Mines’ 100% owned 167 EXTENSION project in the region of the Plan Nord, in Québec.

The survey began on November 13, 2014, and is expected to comprise a data acquisition programme over 3 955 linear kilometres on two different survey blocks at 100 m line spacing. The MAG-TDEM geophysical survey should be completed before the end of the month, Visible Gold said in a statement on Wednesday.

Upon completion of the heliborne survey, consultant Joël Dubé, a specialist in geophysics, would generate anomaly-picking and interpretation maps. “These products will be key in providing prospective guidance on potential diamond drilling targets. A preliminary map will be available soon after the survey is completed and final maps, data and a report are expected within two weeks of completion of the data acquisition,” noted Visible Gold.

A Eurocopter EC120B aircraft equipped with the lightweight ProspecTEM system and a Geometrics magnetometer was being used to carry out the survey.

The company pointed out that this “cost-effective geophysical configuration” was well adapted for reconnaissance surveys with the objective of delineating conductors to a depth of about 150 m while maintaining excellent spatial resolution. “Detailed heliborne MAG-TDEM surveying technology offers excellent penetration results for detecting discrete conductive anomalies as well as mapping lateral and vertical variations in resistivity at depth.” 

Given the conductive and magnetic nature of the angular mineralised boulders found by Visible Gold along Road 167, the MAG-TDEM heliborne technology offered an adapted data combination, thus, increasing the chances of discovering the suboutcropping sources of these boulders.

In addition to the results previously announced on November 11, 2014, Visible Gold on Wednesday also reported the results of five boulders found in the area of KM150 of its 167 EXTENSION project.  Boulder 55916 indicated 10.8 g/t of gold, 9.2 g/t of silver and 0.23% copper; boulder 55866 0.74 g/t of gold, 13.5 g/t of silver, 0.35% copper and 0.36% zinc; boulder 55867 29.31 g/t of gold, 39 g/t of silver and 1% copper; boulder 55868 10.49 g/t of gold, 24.4 g/t of silver and 0.48% copper; while boulder 55869 presented 2.42 g/t of gold, 13.9 g/t of silver and 0.08% copper. 

Following the receipt of all sample results and of the MAG-TDEM geophysical survey, Visible Gold explained that its geological team would review the results and establish an exploration programme to define the bedrock sources of these mineralised boulders. A batch of 16 new mineralised boulders was sent to Techni-Lab Laboratories on November 7, 2014, and results from these boulders would be released as they became available.