The North Sphaler showing area is underlain by Upper Triassic Stuhini Group rocks, which have been intruded by Late Triassic to Early Jurassic monzonitic intrusions, Eocene granitic dikes, sills and stocks and Miocene basaltic and rhyolitic dikes.
In 1989, four contour soil lines were run on the north side of Sphaler Creek by Lorica Resources to test for a projected strike extension of the Gully zone. The North Sphaler Zone, a gold-bearing quartz-chlorite-sulphide vein, was found near one of the two anomalous areas on these lines and trenched.
The showing comprises a 50 to 60 centimetre wide quartz-pyrite-arsenopyrite-sphalerite vein enclosed by intense chlorite altered andesitic tuff and or agglomerate. Chip samples 463825 and 463826, taken across 7.2 metres of vein and alteration from the North Sphaler zone, averaged 2.13 grams per tonne gold and 0.58 per cent zinc (Assessment Report 19479).
Sample 463825 produced a value of 5.4 grams per tonne silver over 5.5 metres (Assessment Report 20956).
Refer to North zone (104G 022) for details of the Trek property work history, of which the North Sphaler showing is part of.