Mesozoic granitic rocks of South Korea : Trace element evidence regarding their differentiation. 2 REE patterns.

To understand the mode of differentiation of the Jurassic and Cretaceous granitic magmas in South Korea, a neutron activation analysis has been made to measure the REE abundance of the granitic rocks.We used the Rayleigh fractionation model as a crystallization model of the granitic melts.Since the model calculations fit the REE data for the Cretaceous granitic rocks very well, it is suggested that the Cretaceous granitic magma in South Korea were mainly differentiated by fractional crystallization.Because the REE patterns for the Jurassic granitic rocks do not show large negative Eu anomalies, it is difficult to consider that the Jurassic granitic magmas were chiefly differentiated by fractional crystallization.