Alkaline Rocks and Carbonatites of the World

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

Megiscane Lake

stripes

Occurrence number: 
031-00-141
Country: 
Canada
Region: 
Quebec
Location: 
Longitude: -75.6, Latitude: 48.57
Carbonatite: 
Yes

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. Spectrochemical analyses gave 0.56% SrO, 0.14% BaO, 0.13% CeO and 0.13% LaO.

Age: 
K-Ar on biotite gave 973±36 Ma and on hornblende 978±40 Ma (Wanless et al., 1972).
References: 

CHARBONNEAU, B.W. 1973. A Grenville Front magnetic anomaly in the Megiscane Lake area, Quebec. Paper, Geological Survey of Canada, 73-29: 1-20.
WANLESS, R.K., STEVENS, R.D., LACHANCE, G.R. and DELABIO, R.N. 1972. Age determinations and geological studies: K-Ar isotopic ages, Report 10. Paper, Geological Survey of Canada, 71-2: 1-96.

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