ID 62129
Title Transcription
トクシマケン アナブキガワ ジョウリュウ コヤダイラ ノ チシツ ト チケイ
Title Alternative
The geology and geomorphology in Koyadaira, upper stream of Anabukigawa area, East Shikoku, Japan
Author
Kitamura, Shin-ichi University of Tokushima
Motoyama, Shigeki Tokushima City Highschool
Tsujino, Yasuyuki Tokushima Prefectural Museum
Nakao, Ken-ichi Tokushima Prefectural Museum
Ozawa, Hiroaki Naruto University of Education
Keywords
剣山
御荷鉾緑色岩
秩父北帯
上韮生川-鮎喰川断層
斜面崩壊
Content Type
Departmental Bulletin Paper
Description
The Mikabu and Chichibu belts in the Anabukigawa arre were studied with respect to their composition,
boundaries and the relation with landslides. The main body of the Mikabu Greenstones is composed of the
MORB-type tholeiite, and the Hawaiian and Polynesian-type alkaline basalts. The greenstones are dominated by
dolerite intrusions into bedded-cherts. The coincidence of the chemical composition attributes the Taigo and
Nakano greenstone bodies to the Mikabu Greenstones. The limestone phyllite of the Mt. Tsurugi was dated by
the occurrence of Late Carboniferous conodonts. The co-occurrence of conodonts and crinoids suggests that the
limestone originates from the tropical reef settings.The Fujinoike-dani Valley and the southern slope along the
Anabukigawa River are characterized by the frequent occurrence of landslides and collupse of forest road-cuts.
Because the faults,that cut the North Chichibu Belt,an d bounds from the Mikabu Greenstone Belt as well as the
Kaminirogawa-Akuigawa Fault that obliquely cut them later,are concentrated in the Fujinoike-dani Valley and
the southern slope along the Anabukigawa Riiver.The landslides are concentrated along the valley walls of the
Anabukigawa River where Mikabu Greenstones and the Sanbagawa green and pelitic schists occur. The
distribution of landslides in the area is controlled by the lithology (distribution of greenstone and schists),the
coincidence of their dipping with valley wall, the contents of swelling clay minerals in the weathered materials,
and the changes in rock properties of pelitic schists due to weathering.
Journal Title
徳島大学総合科学部自然科学研究 = Natural Science Research, The University of Tokushima
ISSN
09146385
NCID
AN10065859
Publisher
徳島大学総合科学部
Volume
22
Start Page
29
End Page
44
Sort Key
29
Published Date
2008-12-24
EDB ID
FullText File
language
jpn
departments
Science and Technology