Shallow dipping structure associated to the Cimandiri Fault: evidence from single station teleseismic receiver function analysis

• Published in: Journal of physics. Conference series Vol. 817; no. 1; pp. 12074 - 12079
• Main Authors: Syuhada, Anggono, T
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 10.04.2017
• Subjects: Dipping; Function analysis; Geological faults; Modelling; Physics; Subduction (geology)
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/817/1/012074

The Cimandiri fault zone is located in the eastern part of the boundary between the oblique subduction of the Indo-Australian plate along Sumatera and the frontal subduction along Java. Even though some geological and geophysical investigations have been conducted and focused on this area, the geometry of the fault zone remains poorly resolved. To provide better constraints on the geometry of the Cimandiri fault zone, we analyze teleseismic receiver functions from single permanent seismic station located in the fault zone. We observe that the computed receiver functions show back azimuthal variation in the amplitude converted waves at the first 2 second of receiver functions providing clear evidence for the presence of complicated shallow structure. We implement forward modelling technique using synthetic seismograms with the same parameters as the observed receiver functions. The modelling reveals at least 2 km thick low velocity zone dipping N-E at 30°, which might be correlated to the Cimandiri fault.