2019 Volume 19 Issue 5 Pages 5_34-5_45
Nowadays, scenario-based strong motion prediction is strongly required quantitatively to show its variation or uncertainty. We focus on the variation or uncertainty of source parameters such as area and stress drop of strong motion generation area (SMGA). Repeating M6-class plate-boundary earthquakes occurring off Kesennuma, northeast Japan, were analyzed. The latest event on May 13, 2015 (M6.8) has 2 SMGAs, and each event in 1973, 1986 and 2002 has one SMGA. SMGA1 of the 2015 event and SMGAs of the 1973, 1986, and 2002 events are close to each other in space, and their spatial extent was almost same. The variation in the estimated stress drop of SMGA is approximately less than 1.6 times of the smallest event.
