Longitude: -77.5, Latitude: 48.25
Dykes of possible nephelinitic affinities occur over a wide area of Quebec approximately between Mattawa and Bachelor Lake. The dykes are up to 60 cm thick and have been described principally from drill core. They comprise olivine (29-48%) and phlogopite (9-26%) phenocrysts in a matrix of calcite (13-39%), augite (0- 6%), perovskite (1-7%), magnetite, ilmenite and analcime.
K-Ar ages on phlogopite gave 1110 Ma for a dyke near Bachelor Lake and 1520 Ma for one from the Noranda area (Currie, 1976a, p. 117).
CURRIE, K.L. 1976a. The alkaline rocks of Canada. Bulletin, Geological Survey of Canada, 239: 1-228. WATSON, K.D. 1955. Kimberlite at Bachelor Lake, Quebec. American Mineralogist, 40: 565-79.
Earth > North America > Canada > Quebec