Verity (Lempriere)
A number of bands and lenses of carbonatite up to 35 m thick lies conformably in mica and hornblende gneisses, and are cut by feldspar-rich pegmatites. An outcrop of sodalite syenite occurs just to the northeast of the area.
A number of bands and lenses of carbonatite up to 35 m thick lies conformably in mica and hornblende gneisses, and are cut by feldspar-rich pegmatites. An outcrop of sodalite syenite occurs just to the northeast of the area.
Alkaline rocks are found in a number of small outcrops along the Rayfield River, but are completely surrounded by younger Miocene- Pliocene plateau olivine basalts.
A northeast-southwest-trending dyke of alnoite, averaging 1.2 m in thickness, cuts sedimentary and volcanic rocks of the Nicola Group (Triassic).
Alkaline rocks occur in an elliptical pluton 3x1.5 km elongated east-west, and a smaller crescent-shaped body to the south.
Nepheline syenite gneisses are found as a conformable horizon 15- 300 m thick on the west flank of the Frenchman's Cap Dome. Beneath are quartzites, which overlie migmatitic gneisses forming the core of the Dome, and above are pelitic schists, paragneisses and calc-silicate gneiss.
On the southeast side of the Frenchman's Cap Dome lies a series of nepheline-bearing gneisses complexly folded within a sequence of biotite, diopside and sillimanite schists and gneisses, amphibolites, quartzites and some calc-silicate rocks. The alkaline gneisses comprise three units.
Nepheline syenite gneiss occurs in the core of a recumbent nappe, where it forms a conformable lenticular body with the central thickest portion high on Trident Mountain. The gneiss, in addition to nepheline, includes perthitic K-feldspar, albite, biotite and aegirine.
Two occurrences of nepheline syenite are reported either side of the lower reaches of the Sullivan River, and a third possible occurrence some 13-15 km to the southeast.
Sodalite veins are reported by Currie (1976a, p. 101) to occur at Mount Laussedat, 77 km northwest of the Ice River Complex.
Currie (1976a, p. 101) reports the occurrence of trachyte at Mount Hunter, 29 km northwest of the Ice River Complex, to which it may be genetically related.