Yuji Ichiyama
Japan Agency for Marine-Earth Science and Technology
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Yuji Ichiyama.
Geology | 2012
Yuji Ichiyama; Akira Ishiwatari; Jun-Ichi Kimura; Ryoko Senda; Hiroshi Kawabata; Yoshiyuki Tatsumi
The Sorachi-Yezo belt, central Hokkaido, Japan, is composed of voluminous tholeiitic basaltic volcanics, and has been thought to be accreted fragments of an oceanic plateau formed in the Late Jurassic Pacific Ocean. Picrites have been reported as pillow lava and hyaloclastite from the Sorachi-Yezo belt. These picrites are characterized by very magnesian olivine phenocrysts (up to Fo [=100* Mg/(Mg+Fe)] = 94.1), which indicate that the primary magma was unusually Mg rich. The estimated MgO of the primary magma and the mantle potential temperature are as high as 29 wt% and 1700 °C, respectively, comparable to those of the Neoarchean komatiites, and higher than those of the Gorgona komatiites and picrites. The rare earth element patterns of the Sorachi-Yezo picrites are divided into two groups that are chemically akin to the Neoarchean komatiites and Gorgona komatiites and picrites, indicating different melting regimes in an extremely hot mantle plume. The Sorachi-Yezo picrites provide evidence for extremely high temperature magmatism, like that of Archean komatiite, caused by melting of the hottest mantle plume among the Phanerozoic oceanic large igneous provinces.
Lithos | 2008
Yuji Ichiyama; Akira Ishiwatari; Kazuto Koizumi
Lithos | 2006
Yuji Ichiyama; Akira Ishiwatari; Yuka Hirahara; Kenji Shuto
Island Arc | 2006
Akira Ishiwatari; Yuki Yanagida; Yibing Li; Teruaki Ishii; Satoru Haraguchi; Kazuto Koizumi; Yuji Ichiyama; Masaru Umeka
International Geology Review | 2004
Akira Ishiwatari; Yuji Ichiyama
Contributions to Mineralogy and Petrology | 2005
Yuji Ichiyama; Akira Ishiwatari
Island Arc | 2004
Yuji Ichiyama; Akira Ishiwatari
Contributions to Mineralogy and Petrology | 2014
Yuji Ichiyama; Akira Ishiwatari; Jun-Ichi Kimura; Ryoko Senda; Tsuyoshi Miyamoto
Mineralogy and Petrology | 2014
Betchaida D. Payot; Shoji Arai; Henry J. B. Dick; Natsue Abe; Yuji Ichiyama
Island Arc | 2007
Yuji Ichiyama; Akira Ishiwatari; Kazuto Koizumi; Yoshito Ishida; Sumiaki Machi