ECLOGITES OF THE MAKSYUTOV COMPLEX, SOUTHERN URALS: GEOCHEMISTRY AND THE NATURE OF THE PROTOLITH

Abstract

Petrochemical and geochemical data make it possible to characterize the nature of the protolith of a boudin from the lower unit of the Maksyutov Complex. The eclogite was determined to have developed after igneous rocks from a single tholeiitic source. Their normative composition corresponds to quartz-bearing hypersthene basalt. The distribution character of incompatible HFSE confirms that the eclogites inherited the composition of their magmatic protolith and points to similarities between the protolithic rocks and enriched tholeiites of the E-MORB type. The uncovered petrochemical and geochemical differences between the eclogites were caused by the crystallization differentiation of basaltic melt in hypabyssal environments during its intrusion into the continental crust prior to subduction onset.