The Motase Southwest showing is hosted in Lower Jurassic Telkwa Formation (Hazelton Group) tuffs, andesites and agglomerates. Near the mineral occurrences the volcanic rocks are cut by steep, light grey feldspar porphyry and quartz porphyry dikes. Porphyritic granodiorite was reported on the Pac 17 and 18 claims.

The Motase group of thirty-five claims lay astride the about 5 kilometres northeast of the southeast corner of the map-area at 56 degrees north 127 degrees west. It was staked by M.S. Lougheed, during the summer of 1945, on behalf of Yukon North-west Explorations, Limited, and prospected and geologically mapped by that company during the same season. The claims are underlain mainly by red, green, grey, and buff, andesitic lavas, tuffs, and agglomerates of the Takla group. Near the known mineral occurrences these dip about 15 degrees southwest and are cut by steep, light grey feldspar porphyry and quartz porphyry dikes, which may be phases of the Kastberg intrusions.

Two mineralized areas form the Motase prospect (104D 002), one about 300 metres northwest of the other, and occupy parts of the precipitous northeast face of the mountain; a third, the Motase Southwest, is reported to occur about 500 metres southwest of the Motase on the relatively gentle southwest slope of the mountain. C.S. Lord reports that principal minerals, bornite and chalcocite, are associated with a little galena, pyrite, chalcopyrite, and possibly tetrahedrite (GSC Memoir 251). These occur mainly in the volcanic rocks. There they occupy minute fractures, or are disseminated throughout an inch or so of rock on either side of fractures, or are scattered through larger masses of rock apparently unrelated to fractures. Less commonly they have partly replaced the borders of porphyry dykes. The minerals are not equally concentrated or abundant in all rock layers.

WORK HISTORY

In 1945, thirty-five claims were staked on the showings in 5 kilometres east of Motase Lake by M.R. Lougheed for Yukon Northwest Explorations Limited. A program of prospecting, geological mapping, and sampling was carried out during the year. A selected sample, collected by the Geological Survey in 1941 from talus on the northeast side of the mountain contained assayed 0.17 gram per tonne gold, 437 grams per tonne silver and 14.9 per cent copper (Geological Survey Memoir 251, pages 62 and 63).

In 2007, Electrum Resources staked ridge area, encompassing the Motase (094D 002) and Motase Southwest occurrences. They conducted 1 day of prospecting over the Motase (094D 002) area. See that occurrence for related details.