The 1995 Hyogoken-nanbu earthquake created 10km-long surface fault ruptures on the northwest coast of Awaji-shima. Due to right-lateral and vertical faulting, characteristic tectonic microforms appeared on the land surface.
This report presents large-scale detailed maps and stereo photographs of four sites where various small-scale faulted and deformed landforms such as pressure ridges, bulges, and so on were observed. Analyses of such microforms expressed in the detailed maps with contour intervals of 2cm or 10cm-and stereo photographs led to two conclusions.
1. Distribution of bulges and depressions on the southeastern block of the fault suggests that the southeastern block moved mainly toward the southwest against the northwestern block. This shows a good agreement with the results of geodesic measurement.
2. Pressure ridges are often separated by tension cracks or faults. This means that during the formation of tectonic microforms, pressure ridges were built up in the earlier stage due to non-faulting phase, followed by tensile or shearing separation in the soft materials in response to increased fault displacement.
