The Topsails complex is one of the largest granitoid bodies in Newfoundland covering an area of 125x50 km. At least four major granite types can be recognized of which only one is peralkaline.
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In the vicinity of Hare Hill, and Talk's Pond lying to the south, peralkaline granites, syenites and aplites with arfvedsonite and aegirine have been identified. Alkaline amphiboles are commonly replaced by biotite, sometimes with a little riebeckite.
A more or less continuously exposed batholith of 30x10 km with a number of outliers, the St Lawrence granite cuts sharply across Proterozoic lavas, pyroclastics and volcanogenic sediments that are conformably overlain by Cambrian sediments.
Numerous monchiquitic dykes occur along the coast and on islands in the southern part of Notre Dame Bay (Strong and Harris, 1974, Fig. 1_1). Titanaugite, biotite and olivine form phenocrysts and analcime is present in the groundmass and, with calcite, in ocelli.
This is an area of granodiorite, granite and syenite overlain by an extensive sequence of ash-flow tuffs. Some facies of the granites and syenites contain abundant riebeckite which Mercer et al. (1985) consider to be metasomatic, but K.L. Currie (personal communication, 1985) feels is not.
The La Scie intrusive complex comprises the Reddits Cove gabbro, the La Scie granite and the Seal Island Bight syenite, only the last being peralkaline.