Alkaline Rocks and Carbonatites of the World

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

Semlin

stripes

Occurrence number: 
031-00-027
Country: 
Canada
Region: 
British Columbia
Location: 
Longitude: -121.05, Latitude: 50.75
Carbonatite: 
No

A northeast-southwest-trending dyke of alnoite, averaging 1.2 m in thickness, cuts sedimentary and volcanic rocks of the Nicola Group (Triassic). The rock contains books of biotite 3 cm in diameter and phenocrysts of olivine, mainly serpentinized, and zoned augite in a groundmass of the same minerals together with melilite, perovskite, magnetite and calcite.

Age: 
Not known, possibly related to the extensive Miocene basalts occurring to the north.
References: 
DRYSDALE, C.W. 1914. Geology of the Thomson River Valley below Kamloops Lake, B.C. Summary Report for 1912, Geological Survey of Canada: 115-50.
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith