Earthquake source parameters at the sumatran fault zone: Identification of the activated fault plane
Fifteen earthquakes (Mw 4.1–6.4) occurring at ten major segments of the Sumatran Fault Zone (SFZ) were analyzed to identify their respective fault planes. The events were relocated in order to assess hypocenter uncertainty. Earthquake source parameters were determined from three-component local waveforms recorded by IRIS-DMC and GEOFON broadband lA networks. Epicentral distances of all stations were less than 10°. Moment tensor solutions of the events were calculated, along with simultaneous determination of centroid position. Joint analysis of hypocenter position, centroid position, and nodal planes produced clear outlines of the Sumatran fault planes. The preferable seismotectonic interpretation is that the events activated the SFZ at a depth of approximately 14–210 km, corresponding to the interplate Sumatran fault boundary. The identification of this seismic fault zone is significant to the investigation of seismic hazards in the region.
KeywordsSumatran Fault Zone three-component local waveform inversion earthquake source parameters fault plane
Unable to display preview. Download preview PDF.
- McCarthy A.J., Elders C.F., Cenozolc Deformation In Sumatra: Oblique Subduction and the Development of the Sumatran Fault System. In: Fraser, A.J., Matthews, S.J., Murphy, R.W. (Eds.), Petroleum Geology of Southeast Asia. Geol. Soc. Spec. Pubs, 1997, 126, 355-363Google Scholar
- Natawldjaya D.H, Neotectonlcs of the Sumatra Fault and Paleogeodesy of the Sumatra Subduction Zone, PhD thesis, California Institute of Technology Pasadena, USA, 2002Google Scholar
- Yeats R., Sieh K., Allen C., The Geology of Earth-quakes, Oxford University Press, New York, 1997Google Scholar
- Lasitha S., Radhakrishna M., Sanu T.D., Seismically active deformation in the Sumatra-Java Trench-arc region: Geodynamic Implications, Current Science, 2006, 90, 690–696Google Scholar
- Santosa B.J., Analyzing the seismogram of earthquakes on Sumatra-Java Subduction plane at CHTO observation station, Journal MIPA, 2005, 13, 23–29Google Scholar
- Klein F.W, HYPOINVERSE, a program for VAX and Pro-350 computers to solve for earthquake locations and magnitudes, U.S. Geological Survey Open-File Report, 1985, 85–515Google Scholar
- Goldstein P., Snoke A., SAC Availability for the IRIS Community, IRIS Consortium, DMS Electronic Newsletter, 2005, 7,www.iris.edu/news/newsletter/vol7no1/page1.htmGoogle Scholar
- Kikuchi M., Kanamori H., Inversion of complex body waves — III, Bull. Seism. Soc. Am., 1991, 81, 2335–2350Google Scholar
- Coutant O., Program of numerical simulation AXI-TRA, Laboratoire de Géophysique Interne et Tectonophysique Report, University of Joseph Fourier, 1990 (in French)Google Scholar
- Zen Jr. M., Dahrin D., Diament M., Harjono H., Karta K., Deplus C., Gerard M., Lassal O., Malod J., Martin A., Mantawai-90 cruise result: the Sumatra oblique subduction and strike slip fault zones. In: Prasetyo H. (Ed.), Geodynamic Processes in the Forearc Sliver Plate and General Topics, Indonesian Assoc. of Geophys., Bandung, 1991, 46Google Scholar
- Kerry S., Natawidjaya D., Neotectonics of the Sumatra fault, Indonesia, Journal of Geophysical Research, 2002, 105, 298–309Google Scholar