R1: Characterization and description of minerals (Joint Session with The Gemmological Society of Japan)

[R1P-03] Chemical features of high-salinity fluid inclusions in quartz crystals from Oohinata acidic rocks, Nagano prefecture.

*Masanori Kurosawa¹, Takuya Tsuda² (1. Life Environ. Sci., Univ. Tsukuba, 2. Grd. Sch., Univ. Tsukuba)

Keywords:fluid inclusion, daughter crystal, SEM, granite, hydrothermal fluid

Daughter minerals in polyphase fluid inclusions of quartz crystals from quartz veins at the Oohinata acidic rocks, Nagano, Japan, were analyzed with a SEM–EDS to examine chemical features of highly-saline and sulfidic hydrothermal fluids from granitoids associated with polymetallic ore deposits in Japan. Many crystals of rock salt, sylvine, pyrite, chalcopyrite, anhydrite, feldspar, muscovite, rutile, barite, sphalerite, fluorite, loellingite, galena, molybdenite, monazite, and vanadium-rich hematite were observed as daughter crystals in the inclusions.