Geodetic Measurements with GPS in Matsumoto Basin, Central Japan (1992-1996)

Abstract

Since 1992, geodetic measurements with GPS have been conducted in Matsumoto basin, Nagano Prefecture, central Japan. The Matsumoto basin is located on the Itoigawa-Shizuoka Tectonic Line, which is recently regarded as a plate boundary between the Eurasian plate and the North American plate. From the present GPS results of the Matsumoto basin, the principal strains measured at the northern area including the Omachi-city were a north-northwest contraction of 2.8±2.3×10^-7/yr and an east-northeast extension of 1.9+2.7×10^-7/yr during 1994-1996. While, at the southern area of the Matsumoto basin including the Matsumotocity, the principal strains measured there were a north-northwest extension of 2.8 t 1.8×10^-7/yr and an eastnortheast extension of 0.6±1.2×10^-7/yr during 1993-1996.