|Author:||Hammouche et al., 2011|
|Type area:||Merville Lake area (NTS sheet 23P02)|
|Geological province:||Churchill Province|
|Geological subdivision:||Mistinibi-Raude Lithotectonic Domain|
|Lithology:||Monzonite and granite|
This unit was defined as the “Cabot Lake and Résolution Lake Intrusion” by Taner (1992) to describe two foliated and mylonitized monzonitic to granitic intrusions. Danis (1991) also used the term “Cabot Lake Granite” in the SE corner of sheet 23P02. The work of Hammouche et al. (2011, 2012) assigned several intrusions to this unit based on their petrographic, geochemical and geophysical similarities. They also elevated the unit to the suite rank and renamed it the “Lac Cabot Suite”.
The Lac Cabot Suite is associated with strong positive aeromagnetic anomalies; it consists of monzonite and granite, locally quartz monzodiorite. These rocks are either foliated to mylonitic or little deformed. Their grain size varies from coarse to fine, and significant grain size reduction associated with mylonitization is visible in places. Rocks are pinkish grey in fresh exposure and light pink in altered surface. They have a porphyroclastic to augen texture with 2cm to 4 cm long K-feldspar phenocrystals. They contain biotite (≤10%), some hornblende, epidote and magnetite. The granitic facies also contains muscovite (≤5%). Sphene (≤4%) generally occurs as a rim around magnetite. Chlorite replaces micas and plagioclase is variously sericitized. Apatite, zircon and allanite are present in accessory amounts. Taner (1992) also mentions the presence of late alteration minerals such as chlorite, carbonate and prehnite.
Thickness and Distribution
The Lac Cabot Suite forms a series of intrusions 0.7 km to 4 km wide by 1 km to 7 km long, specifically in the SW part of the Mistinibi-Raude Lithotectonic Domain (Charette et al., 2019). These intrusions cover a total area of ~66 km2.
Does not apply.