Explosion Seismic Observations in Eastern Kyushu, Japan, II. : Ajimu-Tano Profile.

A seismic refraction survey was conducted along a profile from Ajimu, Oita Prefecture, to Tano, Miyazaki Prefecture, on November 14, 1996. This profile is almost the same as the profile of the survey conducted in 1994. The total length of the Ajimu-Tano Profile was about 230km, and three shots and 236 temporary observation sites were arranged along the profile. Charge size of all shots was 500kg. Record signals of the observation sites in a distance range of less than 120km were of good quality. Travel times of first arrivals indicated the complex velocity structure of the shallow part of the crust. Reflected waves from the deeper part of the crust or the upper mantle were also clearly observed. Analysis of the high-quality data sets obtained in the 1996 and 1994 experiments might reveal a fine image of the crust in this area