Title Transcription
オキ ドウゴ トキバリヤマ ルイソウ ノ カザン マメイシ
Title Alternative
Accretionary lapilli in the Tokibariyama Formation of Dogo,Oki Islands
File
language
jpn
Author
Yamasaki, Hirofumi
Description
Accretinary lapilli are found involcaniclastic rocks in the Tokibariyama Formation is composed of lava flows and volcaniclastic rocks ranging from intermediate to felsic in property. The volcaniclastic rocks containing the lapilli consist mainly of subaqueous pyroclastic flow deposits. The lapilli are commonly spheroidal and elliptical and range in size from l to 6 mm, but occationally broken. Each of them consits of a main part (an inner coaser part with or without a core and an outer finer part) and a surrounding outer shell part. Concentrically layered structure is usually observed in the cross section.A double lapillus (MOORE & PECK, 1962) and a lapillus with an inner coaser part in unique shape (Fig.5-5) are recognized . The lapilli are composed entirely of clastic volcanic materials similar to those of the matrix, but finer in grain size. Judging from the character of the internal structure and mode of occurrence, the lapilli were formed in the air and falled in to pyroclastic flow deposits during transporta, tion and/or deposition of them. Some of the lapilli are presumed to have been formed by agglutination of particles through the medium of ice.
Journal Title
Geological reports of Shimane University
Volume
6
Start Page
85
End Page
93
ISSN
0287816X
Published Date
1987-06-30
NCID
AN00054980
Publisher
島根大学理学部地質学教室
Publisher Aalternative
Department of Geology, Faculty of Science, Shimane University
NII Type
Departmental Bulletin Paper
OAI-PMH Set
Shimane University
Remark
1-11 / 1982-1992
大久保雅弘教授退官記念論誌集,野沢保教授退官記念論詰集