Using Trace Elements in Chromites to Constrain the Origin of Podiform Chromitites in the Thetford Mines Ophiolite, Quebec, Canada

摘要

The Thetford Mines Ophiolite is interpreted as a fragment of a fore-arc oceanic lithosphere. This complete ophiolitic sequence consists of a thick mantle sequence, a plutonic crustal component, and a volcano-sedimentary sequence dominated by boninitic lavas. One third of its 50 chromitite occurrences are podiform and are hosted in a dunitic envelop within the mantle tectonites.