Tracking the Evolution of Magmas from Heterogeneous Mantle Sources to Eruption

This contribution reviews the effects of source heterogeneities, melt-rock reactions and intracrustal differentiation on magma chemistry across mid-ocean ridges, intraplate settings subduction zones using experimental studies natural data. We compare melting behaviors pyroxenites peridotites their relative contributions to magmas as functions composition, mantle potential temperatures lithospheric thickness. also discuss fate chemically distinct melts derived from heterogeneities they travel through a peridotitic mantle. Using nearly 60,000 major element compositions volcanic rocks, melt inclusions, crystalline cumulates, we assess broad petrogenetic trends in large global dataset possible. Consistent with previous studies, ridge basalts (MORBs) cumulates favor first-order control crystal-liquid segregation, while trace emphasize role reactions, highlighting decoupling between two. Ocean island (OIB) show larger compositional variability than MORB, partly attributed variations pyroxenite proportions source. However, estimated vary considerably heterogeneity model thermal structure For arcs, highlight current views downgoing slab into primary arc magmas, overriding lithosphere magmatic chemical filter repository voluminous cumulates. Our approach simultaneously looking at database + deep crustal rocks diverse tectonic underscores challenge deciphering signal versus intracrustal/lithospheric processes.