This paper clarified the deformation mechanism of a shallow landslide in a Tertiary deposit with 3 to 5 meters of maximum snow depth based on the results of two years of monitoring. Landslide activity was low from spring to summer ; however, it increased from autumn to the early snow season, and the extensional deformation increased with it. The creep of the landslide, which stopped briefly in midwinter, started moving at a slow speed without deformation in the snowmelt season. The following

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... ee factors were apparently involved in controlling such deformation:1) increase in shear strength by snow load, 2) net effect of snow pack, and 3)consolidation of the sliding surface by long-term loading of snow pack.