The Bear-Rimini zone is located 2.5 kilometers northwest of the Hinge zone and hosts the LP fault which is thought to have an 18-kilometer strike length. The shallowest gold intercept from the zone was taken from a depth of 53 meters and returned 0.5 meters grading 759.38 g/t gold.
After recognizing a significant hydrothermal alteration zone in the previous round of regional drilling, a new zone of shallow high-grade gold associated with silicification of host rocks related to a crustal-scale structure which is called the LP fault was discovered,. The fault marks a contact between mafic and felsic/intermediate rocks and is spatially associated with an 80-meter to 200-meter-wide quartz sericite zone associated with highly anomalous to high-grade gold mineralization. The LP fault transects the property for approximately 18 kilometres of strike length. The new Bear-Rimini zone joins the Hinge zone as a significant new gold discovery and will be an additional focus of drilling through the remainder of 2019.
- The Bear-Rimini Zone is located 2.5 kilometres northwest of the Hinge Zone.
- The new discovery is hosted by a new exploration target, the “LP Fault”, and adjacent lithologies. Airborne geophysics completed by Great Bear shows the LP Fault and a parallel structure, the “North Fault”, are interpreted to transect the property for 18 kilometres of strike length as shown on Figure 1.
- DNW-011 intersected intervals of gold mineralization across 110 metres of core length and were strongest in a coarse quartz crystal lapilli tuff unit in the northern footwall of the fault. This is the first drill hole in the project’s history to target this tuff unit. Complete assays from DNW-011 are provided in Table 2 at the end of this release.
- The LP Fault is interpreted as a major gold mineralization control and hydrothermal fluid conduit during Archean age gold mineralization. The generally 1 kilometre wide area between the LP and North Faults may represent a significant structural dilation zone where gold rich hydrothermal fluids accumulated.
- The LP Fault has a projected depth of 14 kilometres, extending to base of the continental crust/upper mantle as defined by the Lithoprobe Survey of the Red Lake district, as shown on Figure 2. A similar deep-seated structural feature was interpreted by the Survey to be spatially and genetically associated with the majority of gold mineralization along the main Red Lake mine trend (Zeng and Calvert, 2006) where over 30,000,000 ounces of gold have been produced.
- The LP Fault parallels highway 105, the main access corridor to Red Lake and is 1 to 3 kilometres from a powerline and paved road, and it is a 30 minute drive from the main Red Lake gold mine operated by Newmont Goldcorp Corp.
The Yuma zone was discovered as Great Bear sampled historical drill cores that were taken in a 1.4-kilometer step-out drill hole completed by a previous operator. The hole intersected mineralization that is thought to be connected to the LP fault. Samples taken from the area returned 5.5 meters grading 4.07 g/t gold including 0.5 meters grading 36.90 g/t gold. Great Bear has fast-tracked re-logging and sampling of all available historical drill cores from areas north of the LP fault zone and follow-up drilling is currently underway.
- Historic drill hole DC-12-07 (drilled in 2007 by past operators) is a 1.4 kilometre step-out to the southeast along the LP Fault from Great Bear’s Bear-Rimini discovery hole DNW-011, and was the only other hole to be drilled to-date into the footwall of the LP Fault.
- The final metres of DC-12-07 intersected silicified volcanic rocks visibly similar to those which yielded high-grade gold at the Bear-Rimini discovery. Lower-grade gold mineralization was also intersected higher up the hole within the LP Fault, as was also the case in the Bear-Rimini Zone.
- Great Bear’s geologists noted sparse fine visible gold within strongly silicified felsic volcanic rocks towards the end of DC-12-07, where the Company projected the Bear-Rimini Zone’s on-strike gold mineralization could occur. Past operators had recorded this interval as un-mineralized and it had not been sampled.
- Great Bear sampled the previously uncut core, which assayed 5.5 metres of 4.07 g/t gold beginning at 193.50 metres down-hole, including 2.0 metres of 10.57 g/t gold and including 0.5 metres of 36.90 g/t gold. The historical hole had been terminated prematurely.
Figure 1: Map zoomed into approximately 5 kilometres strike length of the LP Fault at Dixie, showing the Bear-Rimini and Yuma Zones. The location of the nearby Dixie Limb and Hinge Zones are also shown.
The new high-grade “Auro” Zone was drilled at a 2.6 kilometre step-out to the southeast of the Bear-Rimini Discovery area, and 1.2 kilometres southeast of the Yuma Zone along the LP Fault. Highlights include 10.65 g/t gold over 17.25 metres, and the following:
- The Auro Zone is located less than one kilometre to the northeast of the Dixie Limb and Hinge Zones.
- Previously, Great Bear described the Auro Zone as the “DNE” target area, and historical drill intercepts within the LP Fault at this location include 24.6 metres of 0.86 g/t gold. Historical drill holes were located less than 100 metres from Great Bear’s new high-grade discovery.
- Various gold intervals were intersected along 307 metres of core length in discovery drill hole BR-020, as shown in Table 1. Gold mineralization projects to within metres of surface, below shallow gravel cover.
- The same geological units were intersected at the Auro Zone as at the Yuma and Bear-Rimini Discovery Zones, showing apparent continuity of the host stratigraphy and structures along the 3.2 kilometres of strike extent of the LP Fault tested to date. Gold was intersected at the predicted geological contact, as had occurred at the Bear-Rimini and Yuma Zones.
Table 1: Assay intervals from Auro Zone discovery hole BR-020.
*Widths are drill indicated core length, as insufficient drilling has been undertaken to determine true widths at this time.
Average grades are calculated with un-capped gold assays, as insufficient drilling has been completed in the Auro Zone to determine capping levels for higher grade gold intercepts. Average widths are calculated using a 0.10 g/t gold cut-off grade with < 3 m of internal dilution of zero grade.