Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Northwestern Quebec Dykes

stripes

Occurrence number: 
031-00-103
Country: 
Canada
Region: 
Quebec
Location: 
Longitude: -77.5, Latitude: 48.25
Carbonatite: 
No

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.

Age: 
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).
References: 

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.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith