地質学雑誌
Online ISSN : 1349-9963
Print ISSN : 0016-7630
ISSN-L : 0016-7630
報告
愛媛県久万高原町の三波川変成岩類中に新たに見つかった“粗粒な”変塩基性岩体
仲田 光輝楠橋 直齊藤 哲大藤 弘明奈良 正和
著者情報
ジャーナル フリー
電子付録

2019 年 125 巻 6 号 p. 447-452

詳細
抄録

A “coarse-grained” metabasite body has recently been discovered within the Sambagawa metamorphic rocks in Kumakogen Town, Ehime Prefecture, Southwest Japan. The metabasite is exposed at only a few outcrops, although gravel-sized clasts from the metabasite are also found in the overlying conglomerate beds of the Eocene Hiwadatoge Formation. The metabasite rocks generally have a weak foliation compared with the well-developed foliation in the surrounding Sambagawa crystalline schists. The metabasite includes white to gray “porphyroclasts” (composed mainly of albite and zoisite) within a greenish-brown matrix (including actinolite and chlorite). Rock textures and modal mineral compositions of the metabasite gravels in the Hiwadatoge Formation are more varied than those found in outcrops of the metabasite unit itself. Mineral assemblages found in the metabasite and the surrounding mafic schist show that both rock units were metamorphosed under conditions corresponding to greenschist facies.

著者関連情報
© 2019 日本地質学会
前の記事 次の記事
feedback
Top