Abstract
Measurements by a Geodimeter 6BL have been carried out annually since 1977, in the evening within a few hours around sunset, at Tokatomi, Inuyama, Hamanako, Sangane and Mukaiyama base-line network in the southern part of central Japan . Strain rates along base-lines are given by assuming a linear variation in length. During the period between 1977 and 1982, the maximum shear strain rates observed at these five base-line networks amount to 0.1-0.7?Estrain/y, which are consistent with the triangulation results during the late 60-100 years by Geographical Survey Institute . On the other hand, axes of principal strain observed at these networks show various direction and only a part of them is consistent with the results by Geographical Survey Institute. Accumuration of horizontal strains in the southern part of cental Japan, seems to be irregular in time and space.
