The first-order levelling and triangulation were performed from 1952 to 1955 in the Sourthern Part of Hokkaido after the great earthquake of "Tokachi-oki" , Mar. 1952. As the old survey was carried out about fifty years ago , the difference between new and old surveys not only represents the deformation accompanying the earthquake , but also com prises the secular variation of the land. Vertical displacements of the crust is perspicuous in the Fig. 2. It seems that in Hokkaido the land is

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... ed to the south-east on the whole. The Fig. 6 shows that the horizontal displacements of the triangulation stations are small.