The Rhyolite Creek map area is on the northeastern side of the Nisling Range. Summits and ridges in this part of the Nisling Range are between 1400 m and 1800 m above sea level. Much of the upland surface is treeless and is covered with weathered bedrock colluvium. Upland surficial deposits are affected by active periglacial processes such as cryoturbation, nivation and solifluction.

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The Irvine Lake and Gravel lake map-areas (NTS 105B/10,11) lie within the northern Omineca Belt, west of the Tintina-Northern Rocky Mountain Trench (NRMT) fault. The eastern part of the area is underlain by Proterozoic to early Paleozoic metasedimentary rocks of Cassiar terrane, a fragment of the North American miogeocline which has been displaced northward on the Tintina-NRTM fault. The western part of the area is underlain by basaltic metavolcanics, serpentinized ultramafic rocks, metagabbro, and cherty and calcareous metasediments of the Slide Mountain terrane. Unfoliated to weakly foliated granitic intrusives (Marker Lake and Cassiar batholiths and Cabin Creek and Gravel Creek stocks) occur throughout the area intruding both the Cassiar and Slide Mountain terranes. Slide Mountain and Cassiar terranes are juxtaposed by an east-verging thrust referred to in this area as the Zak fault. Southwest of Irvine Lake, the thrust places serpentine, basaltic meta-volcanics, and an undeformed dioritic intrusion onto a footwall consisting of the Proterozoic Tsaydiz Formation and older units. Northwest of Irvine Lake, near Shootamook Creek, the thrust places cherty metasediments of the allochthon onto marble and quartzite inferred to be lower Cambrian Rosella and Boya Formations, respectively. The northern end of the Cassiar batholith extends into the southwestern corner of Irvine Lake map area. Its northeastern contact with rocks of Slide Mountain terrane is a subvertical, northwest-southeast trending mylonite zone several tens of metres wide. Mesoscopic structures including S-C fabrics and shear bands prove dextral displacement parallel to a variably plunging, but commonly sub-horizontal stretching lineation. The mylonite zone lies along a pronounced topographic lineamnet which extends from the trace of the Cassiar fault south of the Alaska Highway northwestwardly into the Irvine Lake map-area rather than veering to the west as previously mapped. Mineral occurrences in this area are primarily near the contact of granitic intrusions and carbonate rocks. Carbonate rocks hosting the deposits belong to the upper Proterozoic Ingenika Group (Swannell, Tsaydiz and Espee formations) rather than the Lower Cambrian Atan Group as has been inferred for nearby deposits in the Rancheria district. Other, non-carbonate-hosted mineral occurrences include a porphyry Mo prospect and Ag, Pb, Zn veins.

Surficial geological map (1:50,000 scale) of Matson Creek and Ogilvie map areas, central Yukon (NTS 115N/9 and 115O/12) including marginal notes on surficial geology and geomorphology.

Surficial geological map (1:50,000 scale) of Stewart River Valley, central Yukon parts of NTS map sheets 115O/2,3,6,7 including marginal notes on surficial geology, geomorphology and placer occurrences.

Thirty-Seven Mile Creek map area, northwest of Whitehorse, straddles the contact between Coast Plutonic Complex and rocks attributed to northern Stikine Terrane. Late Triassic Little River granodiorite and Late Paleocene (57 Ma) Annie Ned granite underlie the western part of the map area. Upper Triassic to Middle Jurassic volcanic and sedimentary rocks of the Lewes River and Laberge groups underlie the eastern part of the map. The contact between Coast Plutonic Complex and Stikine Terrane is marked by the Takhini deformation zone - a region of greenschist, gneiss, mylonite, and amphibolite whose protolith is volcanic rocks of Lewes River Group. Potential mineral deposits in this map area include epithermal and mesothermal quartz veins, and magnetite skarns.

The Talbot Creek map area straddles the Ruby and Nisling ranges. Broad treeless uplands dominate the landscape with summits reaching 2100 m above sea level in the Ruby Range and 1800 m above sea level in the Nisling Range. Upland surfaces are covered with weathered bedrock colluvium and sporadically distributed till deposits from former alpine glaciers and ice sheets. Upland surficial deposits are affected by active periglacial processes such as cryoturbation, nivation and solifluction.

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Surficial geological map (1:50,000 scale) of Garner Creek map area, west-central Yukon (NTS 115O/13) including marginal notes on surficial geology and geomorphology.

Geological map (1:50,000 scale) of southeastern Ogilvie Mountains area, central Yukon (NTS 116A/10) including geological cross sections and mineral occurrences.