ACADSTAFF UGM
| Title | : | The M6.3 Yogyakarta Earthquake of May 27, 2006 Source Mechanism Using Teleseismic Body Wave Inversion |
| Author | : |
HIJRAH SAPUTRA (1) Dr. Wahyudi, M.S. (2) Iman Suardi (3) Dr.rer.nat. Wiwit Suryanto, S.Si., M.Si. (4) |
| Date | : | 10 2020 |
| Keyword | : | Asperity finite fault source, normal fault, point source, strike-slip, teleseismic. I Asperity finite fault source, normal fault, point source, strike-slip, teleseismic. I |
| Abstract | : | Teleseismic body wave inversion has been used to determine the source parameters of the Yogyakarta earthquake on May 27, 2006. Until now, it is suspected that the Yogyakarta earthquake was caused by the Opak’s fault with a strike-slip fault mechanism. However, some field evidence and previous research indicate that the type of fault caused by the earthquake is not a pure strike-slip. This study aims to prove andt o determine the characteristics of the Yogyakarta earthquake using teleseismic body wave inversion. In this study, we use the vertical (Z) component of teleseismicbody wave data from the IRIS data repository. The distance between the station and the source used in this study is about 30o– 90o.For modelling purposes, we used a point source and finite fault source. The moment tensor inversion for the point source mechanism find the fault parameters have a strike 232o, dip 86o, and rake -13o, withaseismic moment of 0.581E + 19 Nm (equivalent with Mw = 6.3, moment magnitude). The depth of the source is 12 km, with the variance of the observed and synthetic wave form is 0.36.The finite fault mechanism gives a parameter for the source with a strike216o,dip 54o,andrake-31o having aseismic moment of 0.246E+20Nm and the source depth of 12 km. The variance was 0.26. The type of fault obtained from this modeling is a normal fault, with a source duration of about 60seconds. The asperity obtained from this inversion has three asperities zones, located in the north, south, and the dip direction of the hypocenter. The maximum slip occurs at the third asperities, which is in the direction of the dip. The maximum energy occurs in the dip direction so that the dominant direction of movement of the fault is a dip. From this study it is concluded that the main cause of the Yogyakarta earthquake was not the Opak fault,but a fault on the east side of the Opak’s river fault. |
| Group of Knowledge | : | Geofisika |
| Original Language | : | English |
| Level | : | Internasional |
| Status | : |
Published
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