The Sako Target was discovered during the due diligence examination of the Property in September 2010. The target is located in the northwest-trending axis of a large geophysically inferred fold defined by iron formation which had been displaced from, or altered within, the fold nose. Two outcrops were sampled that contained 2.15 g/t Au and 1.55 g/t Au from siliceous, white, hard, deformed and altered, felsic porphyries with 1% to 3% disseminated pyrite in contact with iron formation. Other outcrops in the fold axis consist of a mixture of quartz-feldspar porphyry, quartz-sericite-carbonate schist, argillite, iron formation, and gabbro. All of the rocks in the fold axis are highly deformed and schistose.
Secondary hydrothermal alteration of the rocks to mineral assemblages rich in quartz, carbonate, chlorite, and sericite is ubiquitous in all of the rocks in the fold axis, such that, the rocks are referred to as “pipeline rocks”. This is because they are a northwest-trending shear zone (i.e. the Pistol Bay Corridor), through which there has been a massive amount of hydrothermal fluid flow attendant with deformation. Much of the stratigraphy of the Sako target consists of banded, quartz-carbonate-sericite schist and proto-mylonite, which is sometimes gold bearing where it contains more than a few percent pyrite. The most prospective rocks in this shear zone are silicified felsic porphyries and a discontinuous, tectonically dismembered iron formation which is hosted, and intruded by, felsic porphyries.
The silicified porphyries or “high silica rocks” are white, very hard, fine to medium-grained, massive and sometimes stand out topographically as rounded mounds of glacially-polished outcrops. The silicified porphyries are gold bearing wherever they contain secondary iron carbonate, fine quartz stockworks and more than approximately 1% fine grained disseminated pyrite.
The iron formation is finely laminated chert, magnetite, and argillaceous bands. It is commonly demagnetized and mineralized with quartz stockworks, secondary pyrite, hematite, carbonate, and gold. The primary stratigraphy of the shear zone appears to be a volcanic sequence of felsic pyroclastic or volcaniclastic rocks and porphyries interdigitated with argillite and iron formation and intruded by gabbro and quartz-rich porphyries. The north boundary of the shear zone is along the north side of the Sako grid, almost coincident with the road, and the south boundary of the shear zone is not known; it has a minimum width of two kilometres in the Sako Target area and it trends northwest to the Vickers Zone. Ten drill holes comprising a total of 1,562.14 metres were completed at the Sako Target in 2011, 2012, and 2014.
Rock samples in the central part of the Sako Grid
|Sample||Grams gold per tonne||Description|
|893696||87.20||outcrop of silicified iron formation with gossan, wall rock to quartz stockwork, 60% pyrite|
|893697||5.98||angular local float of quartz-sericite-pyrite schist, 50% pyrite|
|893698||2.49||subcrop of quartz-sericite-pyrite schist, 40% pyrite, trace galena|
|893803||0.70||subcrop of quartz-sericite-carbonate breccia, 5% pyrite|
|893804||0.70||subcrop of high silica rock, 40% pyrite|
|893805||38.10||subcrop of high silica rock, 40% pyrite|
|893806||2.49||angular float of high silica rock, 20% pyrite, trace galena|
|893813||<0.05||iron formation outcrop, demagnetized, 3% pyrite|
|893815||11.90||0.50 metre quartz vein in gossanous quartz-sericite schist, 3% pyrite, trace galena|
|893816||0.50||quartz-sericite schist outcrop, 2% pyrite|
Rock samples in the eastern part of the Sako Grid
|Sample||Grams gold per tonne||Description|
|893742||1.47||high silica rock, 1 to 2% pyrite|
|893730||4.79||sericite-carbonate schist, 20% quartz, 3 to 5% pyrite|
|893732||0.23||high silica rock, 2% pyrite|
|893731||0.24||iron formation, strongly magnetic, trace pyrite|
|893721||2.38||high silica rock, 3 to 5% pyrite, 3 to 5% arsenopyrite|
|893720||0.13||foliated, carbonatized argillite, 1 to 2% pyrite|
|893719||6.33||high silica rock, 10% pyrite|
|893716||0.52||high silica rock, 2% pyrite|
|893715||0.71||high silica rock, 1 to 3% pyrite|
The magnetic anomalies of the Sako Target are very low amplitude and low relief, much like the Vickers Target, six kilometres to the west. In 2013, Northquest completed an IP and resistivity survey on a 21.7 line-kilometre geophysical grid. Gold-bearing rock samples and drill holes are associated with a strong chargeability anomaly more than 1 kilometre long and 250 metres wide in the central part of the grid. In the west, the IP anomaly has two west-trending branches that converge in the east to resemble a wishbone. The south limb of the anomaly has all of the drill holes completed to date and appears to be coincident with high silica rocks and iron formation. The north limb is associated with high silica rocks and is untested by drilling. A second, northeast- trending IP anomaly 500 metres long and 200 metres wide is present east of the wishbone anomaly but completely concealed by moraine and untested by drilling. The resistivity anomalies are somewhat similar to the IP anomalies with a wishbone-like central anomaly and a concealed, northeast-trending eastern anomaly. The high resistivity central anomaly coincides with high silica rocks on the north limb, which are untested by drilling, and with high silica rocks and iron formation on the south limb of the wishbone which is where all of the drill holes and all of the gold-bearing rock samples are from.
The target for the 2011 Sako Prospect drilling consisted of several large exposures of pyritic- quartz sericite schist that contain gold bearing iron formation and within a regionally extensive northwest trending deformation zone that has a nominal width of about 900 m. Northquest completed four diamond drill holes aggregating 632.9 m. Three additional holes totalling 454.46 m were drilled in 2012 (Gow, 2012) and three more holes totalling 474.30 m were drilled in 2014 (North, 2015).
Ten drill holes comprising a total of 1,562.14 metres were completed at the Sako Target in 2011, 2012, and 2014. It is worth noting that all of the gold bearing drilling intersections obtained so far were discovered the “old fashioned way” by simply drilling wildcat holes under gold-bearing outcrops without the aid of remote sensing or geophysical methods of any kind. This is the kind of basic exploration that was done 100 years ago in southern Canada when the first gold mines of the Abitibi belt were discovered, and it underscores both; i) the immature stage of exploration of this area, and ii) the potential for the discovery of large, easy to find, near surface gold deposits.
Summary of weighted average grade of gold in all drill holes from the Sako Target
|Hole||Length (m)||Azimuth||Inclination||From (m)||To (m)||Intersection Length (m)||Au (g/t)|
Note: Intersection lengths are core lengths and do not necessarily represent the true width of the mineralized zone. Weighted average grades are calculated from assays of drill core with nominal sample lengths of 1.0 metres. The detection limit of the assay method is 0.05 to 0.002 ppm gold. Some of the samples within the intersected lengths reported in the table are below the detection limit and the assay value for those samples used in the weighted average grade calculation is zero. NSV means no significant values, n/a means not applicable.
PB-11-13 had the best drilling intersection in 2011 of 2.00 g/t over 6.17 m. The hole was drilled below an outcrop that contains 1.55 g/t in a grab sample of siliceous, sericitized, porphyritic felsic rock. Moreover, in the vicinity of PB-11-13, there are a few small outcrops where grab samples contain up to 4.62 g/t from similar rock types and from fragments of banded iron formation.
Three follow up drill holes were completed in 2012. PB-12-01 is an undercut of PB-11-13 and intersected long intervals of low grade gold including 0.24 g/t over 50.21 m and 0.74 g/t over 11.26 m. PB-12-02 was drilled 50 metres east of PB-12-01 and intersected 1.76 g/t over 15.53 m (including 28.60 g/t over 0.73 m) plus 0.43 g/t over 28.12 m. PB-12-03 was drilled 50 metres west of PB-12-01 and intersected three long intersections grading greater than 0.25 g/t including 0.79 g/t over 15.49 m. An interpretation is that the intersected widths and grade of gold encountered in the drill holes increases to the east where there has been no drilling and where there are few outcrops. In summary, gold-bearing rocks have been intersected in drill holes over a strike length of 600 metres and gold bearing surface samples and drill holes are associated with a largely untested IP/resistivity anomaly, the holes that were drilled into the anomaly in 2014 did not intersect gold-bearing rocks.
Plan of future exploration work
Future work may consist of follow up drilling east of PB-12-02, and testing the stratigraphy between the Sako grid and the Vickers Target.
Property Compilation with the location of the Sako Target on TMI
Compilation of the Sako Target with the Tikka target on TMI Detail of the Sako Target on chargeabilityDetail of the Sako Target on resistivityCompilation showing both the Sako and Vickers grids, drill holes, rock samples with and chargeability on the grids and TMI