GEOCHEMICAL STUDY ON TECTONIC SETTING FOR NEOPROTEROZOIC GRANITOIDS, NORTHERN MARGIN OF SONGNEN MASSIF, CHINA

The characteristics of granitoids petrology and geochemistry in the north margin of Songnen Massif indicates that the Neoproterozoic granitic bodies have typical rock association and ortho-succession magmatic evolution series belonging to convergent plate boundary. The Keluo pluton is I-type granite and formed in a tectonic setting of the continental arc. The Shuanghe pluton is S-type granite and formed in the zone of the intercontinental collision. The Jiutoushan and the Liutun units formed in post-orogenic and epeirogenic uplift periods, respectivly. The tectonic magmatism suggests that the plate tectonics had operated in the north margin of Songnen Massif in the Neoproterozoic.