焼岳火山の中尾火砕流堆積物とそれらの放射性炭素年代
1974 年 13 巻 1 号 p. 1-7
詳細
1974 年 13 巻 1 号 p. 1-7
In this paper, authors discuss on 14C data of some samples obtained from the Nakao pyroclastic flow deposits of Mt. Yakedake in the Northern Japan Alps.
The samples consist of stumps, buried soil and pieces of wood or charcoal. As shown in Tab. 1 and Fig. 2, some samples obtained from the upper part of the deposits are dated older than those from the lower. It is considered that the samples which show inconsistency with stratigraphical observation have been derived from the older formation by the avalanche type of pyroclastic flow.
In conclusion, the Nakao pyroclastic flow deposits are divided to three members stratigraphically, whose ages are determined after 14C dating of stumps and buried soil in situ.
