Alkaline Rocks and Carbonatites of the World

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

Level Mountain

stripes

Occurrence number: 
031-00-197
Country: 
Canada
Region: 
British Columbia
Location: 
Longitude: -131.32, Latitude: 58.42
Carbonatite: 
No

Level Mountain, north-western British Columbia, is a volcano belonging to the Northern Cordilleran Volcanic Province. The highest point is Meszah Peak at 2166 m and the whole complex covers an area of ~1800 km2. The mountain is a composite volcano composed of both a mafic shield component and a bimodal stratovolcano cap. Alkaline and peralkaline eruptives are present in both, with alkali basalt and ankaramite (pyroxene-rich basanite/alkali basalt) comprising the bulk of the shield, and trachybasalt, trachyte, peralkaline trachyte, pantellerite, comendite, and rhyolite forming the stratovolcano. Four distinct stratigraphic units of mafic lava flows comprise the shield stage, whereas dome stratigraphy is composed of five bimodal packages of flows and ejecta with felsic compositions dominating at >80%, mostly made up of comendite and peralkaline trachyte. Geochemical data including whole rock major and trace elements and Sr isotope data can be found in Hamilton (1981). Geomagnetic data can be found in Hamilton and Evans (1983) and further descriptions in Wood & Kienle (2001).

Age: 
6.5 Ma to “very recent” from palaeomagnetics (Hamilton & Evans, 1983)
References: 
HAMILTON, T.S., 1981. Late Cenozoic alkaline volcanics of the Level Mountain Range, northwestern British Columbia: geology, petrology, and palaeomagnetism. Doctoral Thesis, University of Alberta HAMILTON, T.S. & EVANS, M.E., 1983. A magnetostratigraphic and secular variation study of Level Mountain, northern British Columbia. Geophysical Journal International, 73, pp 39-49. WOOD, C.A. & KIENLE, J., 2001. Volcanoes of North America: United States and Canada. Cambridge University Press pp 121-123
Map: 
Fig 1. Regional map showing distribuition of flows and cones/domes at Level Mountain (Hamilton and Evans, 1983, Fig 1.)
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith