2019 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 19 - Sep 23, 2019Kyushu University Ito Campus
2019 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 19 - Sep 23, 2019Kyushu University Ito Campus
[S1-08]TEM observation of microtexture of the groundmass pyroxene crystals in the ejecta of the Shinmoedake 2011 eruption「発表賞エントリー」
*Shota Okumura1, Akira Miyake1(1. Kyoto Uni. Sci)
Keywords:
Pyroxene,Nanolite,Shinmoedake,TEM,Microtexture
In the ejecta of Shinmoedake 2011 eruption, groundmass pyroxene crystals have the composite texture of Opx and Cpx. We observed their microtexture by TEM. The diffraction patterns and STEM-EDS analysis reveal that Cpx (Aug, Pig) are attached to an Opx layer on both {100} planes with the same c-axis. The existence of the crystals with the twinning Cpx indicates epitaxial growth of Cpx. Although the crystals have a relatively wide range of composition, smaller crystals tend to be rich in Fe.