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pp.100-122
Intermediated-basic plutons in Jirisan area consist of Pre-Cambrian anorthosite and gabbro, and Jurassic diorite and syenite. Many of bodies of massif type anorthosite are multi-intrusion and intruded by gabbroic rock which compose gabbro, norite, troctolite and leucogabbro. Younger intermediated plutons intruded into older basic plutons and formed contaminated zone at margin of basic plutons. Plagioclase of these plutons is of labradorite(An_(56∼60)) to bytownite(An_(60∼86)) in anorthosite, andesine(An_(35∼49)) in diorite and andesine(An_(30∼41)) in syenite: Continuous variation of anorthosite amount in these plutons suggest that basic and intermediated plutons are a series of differentiated product from two co-magma. Pyroxenes are correspond to salite of CPX, and hypersthene of OPX, and show continuous variation of component diopside to hedenbergite in salite and enstatite to ferrosilite in hypersthene. Variation of these component indicate these plutons are also a series of differentiated product from co-magma. Two synchronous plutons plotted on Harker diagram and AMF diagram show mostly similar trend to Daly's values and calcalkali rock series. Accoding to REE(La/Yb)_(cn) and Eu/Sm, it is concluded that intermediated-basic pluton having enriched LREE than HREE and emplaced by the tectonic setting in continent and/or continental margin.
