GEOLOGICAL AND PETROLOGICAL STUDY ON MAGNESIAN ANDESITES IN ISLAND ARC

1.博宁岛玻安岩的研究。Shiraki和他的同事在阿尼吉马的Takinoura发现了最富镁的斜长石玻安岩。它含有玻安岩中最富FO和NiO的橄榄石，镍在橄榄石和液体之间的分配系数高达12。Maruyama等人。汇编了阿尼吉马的地质学。黑田东彦和他的合作者发表了一项关于含铁辉石英安岩的岩石学研究，这是与玻安岩形成岩浆的最新区别。色头池火山岩带中的红柱石及相关岩石研究。Shiraki et al.在山口县东南部发现了大量的镁质安山岩，并对其进行了详细的地质、岩石学、矿物学和地球化学研究。Shiraki和Nomura报道了岐阜县米诺卡莫市下中新统八谷组中的一种镁质安山岩。其他地区镁质安山岩的研究。Shiraki et al.Shijo和Kato分别描述了琉球群岛伊里奥莫特-吉马和库姆-吉马的镁质安山岩。Nanao和Sakaguchi在Hisatsu火山岩的原始岩浆中发现了镁质安山岩。高桥在伊豆半岛西山群底部发现了镁质安山岩。古山、佐藤等人描述了日本海一侧的镁质安山岩。分别是冈村和吉田。

1. Study on Bonin Island boninites. Shiraki and co-worker discovered the most Mg-rich, clinoenstatite boninites in Takinoura, Ani-jima. This contains the most Fo- and NiO-rich olivine in the boninites, and the partition coefficient of Ni between olivine and liquid revealed a high value of 12. Maruyama et al. compiled the geology of Ani-jima. Kuroda and co-investigator published a petrological study on ferropigeonite-bearing dacites, which are the latest differentiates from boninite-forming magma.2. Study on sanukites and related rocks in the Setouchi volcanic belt. Shiraki et al. discovered a large number of magnesian andesites in southeastern Yamaguchi Prefecture and carried out detailed geological, petrological, minetalogical and geochemical studies on them. Shiraki and Nomura reported a magnesian andesite from the lower Miocene Hachiya formation in Minokamo-shi, Gifu Prefecture.3. Study on magnesian andesitet from other region. Shiraki et al. and Shijo and Kato described Magnesian andesites from Iriomote-jima and Kume-jima, Ryukyu Islands, respectively. Nanao and Sakaguchi found magnesian andesites in primitive magmas of the Hisatsu volcanic rocks. Takahashi discovered magnesian andesites in the base of the Nishina group in Izu Peninsula. Magnesian andesites in the Japan Sea side were described by Furuyama, Sato et al. and Okamura and Yosida, respectively.