Archer Exploration Corp. announced that it has received very encouraging results from down hole electromagnetic (DHEM) surveys recently completed on its 100%-owned Grasset Ni-Cu-Co PGE project located in the Abitibi Greenstone Belt of Quebec, Canada. The downhole surveys were conducted by Abitibi Geophysics using the InfiniTEM® XL dual loop system and totaled 3,085 metres in five boreholes.

The surveys defined several deep-seated, strongly conductive targets along the H1 Horizon. Of particular interest are three strong and deep DHEM anomalous plates (Figure 1) best defined by the survey in hole GR-23-03. This hole, drilled in May 2023, yielded the best intersection to date within the H1 Horizon with 1.82% Ni over 4.60 metres, including 5.75% Ni over 0.60 metres (see news release dated June 15, 2023).

The three large conductors contain known mineralized intercepts in their periphery but remain largely untested. The size of the three modeled DHEM anomalies suggests a much better continuity at depth when compared to the numerous small plates detected closer to surfaceArcher Exploration Corp. announce that it has received very encouraging results from down hole electromagnetic (DHEM) surveys recently completed on its 100%-owned Grasset Ni-Cu-Co PGE project located in the Abitibi Greenstone Belt of Quebec, Canada.

The downhole surveys were conducted by Abitibi Geophysics using the InfiniTEM® XL dual loop system and totaled 3,085 metres in five boreholes. The surveys defined several deep-seated, strongly conductive targets along the H1 Horizon. Of particular interest are three strong and deep DHEM anomalous plates (Figure 1) best defined by the survey in hole GR-23-03.

This hole, drilled in May 2023, yielded the best intersection to date within the H1 Horizon with 1.82% Ni over 4.60 metres, including 5.75% Ni over 0.60 metres (see news release dated June 15, 2023). The three large conductors contain known mineralized intercepts in their periphery but remain largely untested. The size of the three modeled DHEM anomalies suggests a much better continuity at depth when compared to the numerous small plates detected closer to surface.

Average conductivity measurements of drill core that was near the conductive plates: Mudstone: 12 S/m; Massive pyrite: 58.6 S/m; Massive pyrrhotite + pentlandite (H1 in GR23-03): 38,026 S/m. This suggests that semi-massive to massive pyrrhotite (± pentlandite) is the most likely source of the highly conductive DHEM anomalies. The three newly modeled conductive plates identified begin 360 metres below surface and have not been previously drill tested. Physical property measurements were taken on drilling core near the target plates with a TerraPlus KT-10 Magnetic Susceptibility and Conductivity meter.

The measurements were done on potentially conductive lithologies close to the northern contact of the main ultramafics around the expected location of the extension of the H1 Zone. The average of 42 measurements on mudstone with disseminated graphite (mudstone) gave 12 S/m, with the being 248 S/m (holes GR23-02, GR23-05). Two measurements on the barren massive sulfides (60-80% pyrite) in hole GR23-02W1 gave 16.8 and 99.6 (average 58.6).

The conductivity value obtained on the massive pyrrhotite with pentlandite that assayed 5.75% nickel over 0.60 metres in hole GR23-03 was 38,026 S/m. This indicates that the mudstone and the massive pyrite are relatively poor conductors and unlikely sources of the strong DHEM anomalies at depth. Comparing those measurements to the conductivity of the DHEM plates (Table 1) suggests that the most likely source of the conductive plates is massive pyrrhotite +/- pentlandite. It should be noted that small lenses of barren pyrrhotite have also been identified in the mudstone in some holes.

It is thought that these may not be as extensive compared to nickel-bearing pyrrhotite in the ultramafics and could be filtered out by their location in the stratigraphy.