| Summary: | The Sumatran Fault has been subjected of scientific researches for decades. Katili (1967) is regarded
as the earliest work for defining The Sumatran Fault having transcurrent deformation in the light of
plate tectonics. Following the work of Katili (1967), Bellier and Sebrier (1994) proposed structural
interpretation of Sumatran Fault pull-apart basins using SPOT images. In 2000, Sieh and Natawidjaja
published their work concerning neotectonics of Sumatran Fault. Previous works emphasizes on
intensive segmentation of Sumatran Fault as distinctive feature. To address the segmentation of
Sumatran Fault, concerns should be paid to tectonic evolution of the area. Sumatra was built based
upon continental collisions from Late Paleozoic to Late Mesozoic. The collisions generated NW-SE
trending basement structure (Barber et al., 2005). Counterclockwise rotation of Sundaland on Middle
Miocene triggered the activation of Sumatran Fault in right-handed kinematics. Pre-existing basement
structure facilitated the deformation. Sumatran Fault has right-stepping geometry, so that several pullapart basins develop along the fault. This paper concerns with current interpretation of fault
configuration based on SRTM data. Interpretation runs from Aceh, Kutacane Graben, Toba Caldera,
Tarutung-Sarulla Basins, Barumun-Angkola Segments, Lake Singkarak, Muaralabuh-Sungai Penuh
Basins, Musi-Manna Segment, Lake Ranau, Suoh Valley, and Sunda Strait. Fault interpretation aims to
classify Sumatran Fault pull-apart basins in terms of structural mechanism and kinematic models.
Structural mechanism comprises fault-bend and oversteps basins. Meanwhile, kinematic models
emphasizes on fault configuration. New division of Sumatran Fault is proposed, applying structural
mechanism as the basis. Sumatran Fault can be packaged in three repetitions of fault-bend mechanism
followed by overstep one. Northern, central, and southern structural packages are elaborated in the
paper.
Kata kunci : Sumatran Fault, Basement Structures, Fault-bend Basin, Overstep Basin, Structural
Mechanism, Kinematic Model
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