松本盆地の第四紀地質の概観 : 松本盆地の形成過程に関する研究(1)

概要

論文の詳細を見る
The Matsumoto Basin Research Group was organized in March, 1971, to clarify the geological history of the Matsumoto Basin. The results of studies obtained during the last year are as follows. 1) A geological map on the Quaternary of the Matsumoto Basin was constructed for the first time. 2) The crystal ash beds in the Nashinoki Loam Formation are correlated to the so-called biotite pumice beds (B_1, B_2, B_3) around Yatsugatake Volcano, while the crystal ash may had been erupted from the volcano around Kumonotaira to the north of Mt. Mitsumatarenge in the midst of the granitic rock area of the Japanese Northern Alps. 5) The Nashinoki Gravel Formation is the products of the first, large scale deposits filling up of the Basin with gravel. It shows that the formation of the Basin set out first in that age. 4) Simultaneously with the accumulation of the Nashinoki Gravel (or the subsidence of the Basin), the Northern Alps began to rise and the peculiar volcano (with the crystal ash) started its activity.
日本地質学会の論文
1972-12-25