@article{MuksinHaberlandBaueretal.2013,
  author    = {Muksin, Umar and Haberland, Christian and Bauer, Klaus and Weber, Michael H.},
  title     = {Three-dimensional upper crustal structure of the geothermal system in Tarutung (North Sumatra, Indonesia) revealed by seismic attenuation tomography},
  series = {Geophysical journal international},
  volume    = {195},
  journal   = {Geophysical journal international},
  number    = {3},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0956-540X},
  doi       = {10.1093/gji/ggt383},
  pages     = {2037 -- 2049},
  year      = {2013},
  abstract  = {The geothermal potential in Tarutung is controlled by both the Sumatra Fault system and young arc volcanism. In this study we use the spatial distribution of seismic attenuation, calculated from local earthquake recordings, to image the 3-D seismic attenuation of the area and relate it with the temperature anomalies and the fluid distribution of the subsurface. A temporary seismic network of 42 stations was deployed around Tarutung and Sarulla (south of Tarutung) for a period of 10 months starting in 2011 May. Within this period, the network recorded 2586 local events. A high-quality subset of 229 events recorded by at least 10 stations was used for the attenuation inversion (tomography). Path-average attenuation (t(p)*) was calculated by using a spectral inversion method. The spread function, the contour lines of the model resolution matrix and the recovery test results show that our 3-D attenuation model (Q(p)) has good resolution around the Tarutung Basin and along the Sarulla graben. High attenuation (low Q(p)) related to the geothermal system is found in the northeast of the Tarutung Basin suggesting fluid pathways from below the Sumatra Fault. The upper part of the studied geothermal system in the Tarutung district seems to be mainly controlled by the fault structure rather than by magmatic activities. In the southwest of the Tarutung Basin, the high attenuation zone is associated with the Martimbang volcano. In the Sarulla region, a low-Q(p) anomaly is found along the graben within the vicinity of the Hopong caldera.},
  language  = {en}
}
@article{MuksinHaberlandNukmanetal.2014,
  author    = {Muksin, Umar and Haberland, Christian and Nukman, Mochamad and Bauer, Klaus and Weber, Michael H.},
  title     = {Detailed fault structure of the Tarutung Pull-Apart Basin in Sumatra, Indonesia, derived from local earthquake data},
  series = {Journal of Asian earth sciences},
  volume    = {96},
  journal   = {Journal of Asian earth sciences},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {1367-9120},
  doi       = {10.1016/j.jseaes.2014.09.009},
  pages     = {123 -- 131},
  year      = {2014},
  abstract  = {The Tarutung Basin is located at a right step-over in the northern central segment of the dextral strike-slip Sumatran Fault System (SFS). Details of the fault structure along the Tarutung Basin are derived from the relocations of seismicity as well as from focal mechanism and structural geology. The seismicity distribution derived by a 3D inversion for hypocenter relocation is clustered according to a fault-like seismicity distribution. The seismicity is relocated with a double-difference technique (HYPODD) involving the waveform cross-correlations. We used 46,904 and 3191 arrival differences obtained from catalogue data and cross-correlation analysis, respectively. Focal mechanisms of events were analyzed by applying a grid search method (HASH code). Although there is no significant shift of the hypocenters (10.8 m in average) and centroids (167 m in average), the application of the double difference relocation sharpens the earthquake distribution. The earthquake lineation reflects the fault system, the extensional duplex fault system, and the negative flower structure within the Tarutung Basin. The focal mechanisms of events at the edge of the basin are dominantly of strike-slip type representing the dextral strike-slip Sumatran Fault System. The almost north south striking normal fault events along extensional zones beneath the basin correlate with the maximum principal stress direction which is the direction of the Indo-Australian plate motion. The extensional zones form an en-echelon pattern indicated by the presence of strike-slip faults striking NE SW to NW SE events. The detailed characteristics of the fault system derived from the seismological study are also corroborated by structural geology at the surface. (C) 2014 Elsevier Ltd. All rights reserved.},
  language  = {en}
}