RELATIONSHIP BETWEEN JADEITITE AND RODINGITE IN SERPENTINITE COMPLEX

Abstract

Jadeitite is a well known but rare rock type that is found only in a few places in the world. Jadeites are always found in the subduction and subsequent continental collision zone, associated frequently with blueschist facies and occasionally with eclogite facies. Based on the investigation of mineral assemblages, bulk chemical composition, microscope textures and the occurrences of the distribution of jadeitites worldwide, three types of jadeitite have been classified in the text. These, which all oecur in tectonic rock inclusions in serpentinite body, are jadeitite veins produced from metasomatic process along the fractures in the serpentinites; massive jadeitites resulted from metamorphic process, and jadeitites formed from mixing processes of metasomatism and metamorphism. In addition, the paper highlights the relationship between jadeitites and rodingites during serpentinization by studying chemical characteristics and evolution of the fluid for forming these two rocks, and proposes a model for the formation of jadeitite in ocean-floor and in the super subduction zone (SSZ) background.