The Baie-des-Moutons intrusion is a ring complex predominantly of syenitic composition. However, the syenites are only marginally alkaline as indicated by the presence sometimes of green rims on pyroxenes (R.F. Martin, personal communication, 1983).
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Within an area of about 24x11 km west of Castignon Lake numerous dykes and diatremes of carbonatite and meimechite cut early Proterozoic (Aphebian) sediments of the Labrador trough (Dimroth, 1970). There are about a dozen diatremes of which the largest is approximately 950x900 m.
Three nepheline syenite intrusions lying some 65 km northwest of Schefferville, and close to the Goodwood River, are foliated and lineated parallel to the enclosing Superior Province gneisses, but also form dykes cutting them, so must have been intruded prior to the Kenoran Orogeny.
North of Cawood a body of nepheline-bearing gneiss, about 1.5 km across, is surrounded by marble, but contacts are not exposed. Most of the occurrence consists of homogeneous gneiss with 5-20% biotite and amphibole and some 10% nepheline.
Carbonatite occurs at Dam Lake 15 km north-northeast of Quinnville (031-00-114).
In the Haycock Mine the iron mineralization is related to veins adjacent to which is a zone of fenitization. This involves development of phlogopite, eckermannite, apatite, aegirine, hematite, calcite, baryte and quartz. Thought to be contemporaneous with the Meach Lake carbonatites.
A small body of carbonatite lies 1.9 km north-northeast of Quinnville. Unfortunately the outcrop was built over before it could be studied in detail.
Intruded into igneous and metamorphic rocks of the Grenville Province close to the fault defining the northern margin of the Ottawa Graben, the Chatham-Grenville stock consists of two early syenites and two later granite intrusions.
A carbonatite body of approximately 6x2 km elongated northeast- southwest is intruded into granite gneiss along the Grenville Front. The carbonatite is a coarse grained black, massive rock of green pyroxene, red-brown biotite, magnetite, pyrite and a little apatite.
Currie (1976a, p. 135) reports the presence of carbonatite dykes in road-cuts along the highway west of Baie-Comeau. The country rocks are fenitized.