Andesine megacrysts in alkali basalts from Japan |
| |
Authors: | Ken-ichiro Aoki |
| |
Institution: | (1) Institute of Mineralogy, Petrology and Economic Geology, Tohoku University, Sendai, Japan |
| |
Abstract: | Andesine megacrysts up to 3 cm in size occur sporadically in certain alkali basalts and allied mafic rocks in southwestern Japan. They are sometimes accompanied by megacrysts of mafic minerals and ultramafic and mafic inclusions. Nine andesines have been chemically analysed.From the petrography and chemistry and the results of high pressure experimental work, it is suggested that andesine megacrysts crystallized from alkali basalt magma under dry conditions at a depth of about 30 to 60 km. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|