Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

Along the southern margin of the Damara mobile belt are over 60 ultramafic bodies. Field and laboratory studies indicate that these fulfil the criteria for Alpine serpentinites, i.e. (a) the bodies occur in a linear belt parallel to the axis of the Damara mobile belt; (b) the bodies were tectonically emplaced; (c) olivine covers a limited composition range (Fo90-F09s). A large data base of chemical analyses of serpentinites derived from layered complexes, Alaskan complexes, komatiites and Alpine complexes was subjected to multivariant analyses. It was shown that there is a difference in chemistry in rocks from these four groups, and that the Damara serpentinites most closely resemble Alpine material.