Abstract
Kirigamine Plateau is a volcanic plateau of aspite type in Central Japan and its height is about 1, 300 m to 1, 900 m above the sea. Japanese archaeologists have discovered several sites of pre-ceramic age on this plateau recently.
The authors have investigated to know the time when the sites were formed and the natural environment of the time. The results are summarized as follows;
1) The culture of the sites is divided into the blade type industry and the mixed type industry which contain the moderate number of point and knife.
2) Viewed through the analysis of the deposits, it is thought that the former was formed in the duration from the latest glacial period to the earlier part of post-glacial period. In the duration, the climatic condition was colder and drier than those of the present time and the active frost action affected on this plateau. In the duration when the latter was formed, the peri-glacial frost phenomena was almost ended by climatic change.
