抄録
The Quaternary clay which occurs along the margin of the Kitami basin, Hokkaido, -to be called Kitami clay-has been known as very sensitive as those of the “Quick clay” in southern Scandinavia and eastern Canada.
The present geological study proved that this clay resembles to the varved clays as shown by its properties as follows:
1. The clay assumes thin bedded and intercalated in the Kutcharo volcanic ash formations.
2. About half of the specimens of the fossil diatoms in the clay is of lacustrin fresh, and another half is of high land lacustrin type.
3. The radiocarbon dating of the wood fragments from the clay gave the age from 23, 000 to 26, 800 years B. P., corresponding to Main Wurm Glacial stage.
4. The caly beds consist of the alternating lamina of summer silty layer and winter peaty layer.
5. By X-ray diffraction and differential thermal analysis, the clay minerals of the clay are identified mainly as halloysite accompanied with minor amount of kaolinite. This mineral composition greatly differs from the “Quick clay” mentioned above, inspite of the sensitive characteristics of the crude clay.
