2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

Sep 15 - Sep 19, 2021Online
日本鉱物科学会年会
2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

Sep 15 - Sep 19, 2021Online

[R8-03]Constraint on deformation temperatures of the Karasaki mylonite, western Shikoku

*Yoshihiro Nakamura1, Kazuhiro Miyazaki1(1. Geological Survey of Japan, AIST)

Keywords:

Karasaki mylonite,Sanbagawa metamorphic rock,EBSD

Karasaki mylonite preserves asymmetric type I crossed girdles with maxima around poles to the rhomb planes, which have small opening angles between 41° and 57°. The type I crossed girdle pattern in the Sanbagawa metamorphic rock has similar opening angle of 51°. The quartz c-axis opening angles indicate deformation temperatures of 330–440 ± 50 °C, and 400 ± 50 °C based on quartz opening angle thermometry. Estimated deformation temperatures are well consistent with peak temperatures of 421 ± 41 ℃ determined from RSCM thermometry.