Chemistry and origin of trapped melts in ophiolitic peridotites

A detailed study has been performed of the major and trace-element compositions of minerals from: (1) plagioclase-bearing peridotites pertaining to different ophiolitic massifs (Internal Ligurides, Northern Apennine; Mt. Maggiore, Corsica) and (2) three olivine-cumulate samples from meter-scale magmatic pods within the Mt. Maggiore mantle ultramafics. This paper focuses on the major and trace element chemistry of clinopyroxenes and plagioclases, which are the main host of many trace elements (like REEs and Sr) in the investigated rocks. The major aims of this report are (1) to provide a detailed microtextural and chemical investigation on melt-peridotite interaction processes, as recorded in the studied ophiolitic peridotites and (2) to furnish data about the geochemical signature of the trapped melts, which are relevant to the understanding of melt dynamics in the upper mantle. (AIAA)