DescriptionIjolite (Oka Carbonatite Complex, Early Cretaceous, 124-125 Ma; Oka Niobium Mine, Quebec, Canada) (14822252052).jpg
Ijolite sample (5.1 cm) with calcite, nepheline, pyroxene, and titanium mineral(s).
The Oka Carbonatite Complex is located in Quebec, Canada. It’s a large body of alkaline igneous rocks intruded through Precambrian metamorphics. The Oka occurs in the western part of the Canadian Shield’s Monteregian Hills Province. Published research indicates that Oka rocks cooled from magma produced by partial melting of upper mantle rocks (inferred to be metasomatized garnet lherzolites). The rocks in the complex contain some rare elements, including economic concentrations of niobium (Nb). Several mines exploit Oka rocks for their Nb content. Oka rocks include coarsely-crystalline calciocarbonatites (a.k.a. sövites; a.k.a. C1 calciocarbonatites), alnoites, ijolites, and okaites.
Age: mid-Barremian Stage, mid-Early Cretaceous, 124-125 million years.
Locality: Oka Niobium Mine, southeastern part of the Oka Hills, Oka Hills Inlier, Deux-Montagnes County, just west of Montreal & Laval, far-southern Quebec Province, southeastern Canada.
de partager – de copier, distribuer et transmettre cette œuvre
d’adapter – de modifier cette œuvre
Sous les conditions suivantes :
paternité – Vous devez donner les informations appropriées concernant l'auteur, fournir un lien vers la licence et indiquer si des modifications ont été faites. Vous pouvez faire cela par tout moyen raisonnable, mais en aucune façon suggérant que l’auteur vous soutient ou approuve l’utilisation que vous en faites.
https://creativecommons.org/licenses/by/2.0CC BY 2.0 Creative Commons Attribution 2.0 truetrue