1958 Volume 1958 Issue 36 Pages i-4
A set of splendid sorted polygons was found in the shallow depression on the ridge near Mt. Tomuraushi in the Central Highland of Hokkaido. The spot is located at 2 km north of the highest peak (2,141 m above m.s.l.) of Mt. Tomuraushi (43.5° ca. N; 142.75° ca. E), and is at the level of about 1,840 m in height. As has been known, TROLL published in 1944 his opinion that sorted polygons might be classified into two types, i.e. the polar type and the tropical type with respect to climatic features over the world. The diameters of the polygons on Mt. Tomuraushi vary from 1.0 to 1.5 m, therefore the polygons should be referred to the polar type of TROLL'S classification. Both types of sorted polygons, however, can be seen occurring side by side on the mountains in Japan, and the polygons of polar type are essentially on the level ground where water is enough to make soils like porridge. Water in the ground is probably an essential element in determining the size of the polygons. Several other examples in Hokkaido and Honshu are also shown in the photographs.
