XFEM SIMULATION OF RUPTURE DIRECTION ON BRANCHING FAULT

Abstract

In the main shock of the 2016 Kumamoto earthquake, the rupture episode of the branching fault was inconsistent with conventional models. In the conventional models, rupture directions are assumed to be from major fault segments to their branches. In this study, we examined rupture patterns of branching fault systems by considering a variety of fault strengths and initial stress fields. In order to simulate the fault rupture including branching points, we proposed a new representation of enrich function for XFEM. The results suggest that ruptures can start from a branching point.