R4: Mineral sciences of the Earth surface

[R4-06] Interlayer structure changes of experimentally weathered phlogopite

*Sayako Inoue¹, Kenji Tamura², Kei Midorikawa^2,3, Toshihiro Kogure⁴ (1. Ehime Uni. GRC, 2. NIMS, 3. Hosei Univ., 4. Uni. Tokyo)

Keywords:phlogopite, weathered mica, interlayer structure, HRTEM

We investigated the interlayer structure of experimentally altered phlogopite. The structure of Al-phlogopite consists of vermiculite-type structure with interlayer hydrated Al and chlorite-type structure with Al hydroxide interlayer sheet. HRTEM showed that two types of interlayer Al coexist within a single interlayer region. When the interlayer Al of this sample was re-exchanged with K, the Al hydroxide interlayer sheet remained, resulting in the formation of the wedge-shaped interlayer space.