Namweon granite body is classified into four rock types in terms of mineral composition, texture and intrusion-emplacement ages. The four rock types are hornblende-biotite granodiorite, porphyritic granodiorite, biotite granodiorite and two mica granite. Geochemical and EPMA data of this rock body suggest that Namweon granite might be a series of magmatic differentiated products by mostly fractional crystallization and partly under nonequilibrium condition. Namweon granite shows different occurence pattern from Daebo granites which lie parallel to Sinian direction. The occurence pattern considers to be one of Songrim Disturbance. The geochronological data for Namweon granite is 211±3 Ma from whole rocks by Rb-Sr method and 203±10.2 Ma from hornblende by K-Ar method. All of these data indicate that igneous activity of Namweon granite continued from late Triassic to the beginning of Jurassic. It is concluded that the Namweon granite body is igneous complex produced by igneous activity during Songrim Disturbance.
Hong et al. (Tue,) studied this question.