Examination of discernment technique of granitoids for hinterland analysis; An Example for Ryoke and Sanyo granites at Chubu district, central Japan

Hanamuro, Takahiro  ; Yasue, Kenichi; Shibata, Kenji; Umeda, Koji; Takatori, Ryoichi*

Petrographical and geochemical approaches were adopted by samples of the Inagawa Granite and Naegi-Agematsu Granite, distributed along upper river basin of Toki River. And gravel from upper layer of these rock bodies were investigated for identification of granitic rock bodies. Petrographic feature of these rock bodies are distinguished by hornblende or muscovite contents. Major element analyses of biotites by EPMA showed the samples from the Naegi-Agematsu Granite were rich in Fe relative to those from the Inagawa Granite. By using this method, the gravel from upper layer of these rock bodies is suggested to be from the Naegi-Agematsu Granite area. Therefore, chemical composition of biotite suggests good indicator for hinterland analysis in this case.