R1: Characterization and description of minerals

[R1P-11] The characteristic growth habits of phillipsite formed in Chichijima, Ogasawara Islands

「発表賞エントリー」

*Yuki Inoue¹, Mana Yasui², Hiroshi Hagiya¹, Atsushi Yamazaki ² (1. Tokyo City Univ., 2. Waseda Univ.)

Keywords:Phillipsite , Step growth, Boninite, Chichijima

Descriptions of various zeolites in the boninite and related rocks in Ogasawara Islands Chichijima and Anijima are reported.In this study, we focused on the characteristic crystal growth structure of phillipsite zeolite in the cavity of the volcanic rock of Chichijima. As a result of SEM-EDS analysis, at least three or more growth modes were observed. The extraframework cations of phillipsite filling in the rock cavity changes from the onset of growth to Na-rich, K-richi and Ca-rich in relation to the change in crystal habit.