The
Great Sumatran fault 1900 km in length is a major
strike-slip fault zone that cuts through the island of Sumatra. It accommodates the right-lateral strike-slip component of the highly oblique collision zone between the
Indo-Australian plate and the
Sunda plate. The
Sunda megathrust carries the dip-slip component of the collision with the upper portion of the over-riding plate separated from the Sumatran fault zone by a small crustal sliver near the volcanic arc. The Great Sumatran fault is considered an example of slip partitioning. The fault runs through the north in
Banda Aceh and ends in the south near the Sunda Strait. The Fault runs northwestward with ranging slip rates of 38 ± 4 mm/yr commonly cited for
Aceh, however, some geodetic data believe that the elastic strain in the area is at around 16 ± 6 mm/yr and 20 ± 6 mm/yr across the parallel Aceh and Seulimeum segments from 2005 to 2010. In the Sianok segments, near the epicenter of the 1926 event, it is proposed to have slip rates of 10–11 mm/yr as well as 27–28 mm/yr for the Renun segment near Toba. The latter proposes that it has a slip rate of about 23 ± 3 mm/yr based on the deflections of the rivers nearby the young Toba tuff. The Toru segment has a slip rate of 7–14 mm/yr which also traverses near the Sibuabuali volcano. The Angkola segment, parallel to the Toru segment, observe slip-rates of about 17 ± 6 mm/yr. In the south, the slip-rates of the Musi segment have a recorded geological slip-rate of 11 ± 5 mm/yr and lastly, the slip-rates for the Kumering segment were a preliminary 6 ± 4 mm/yr, later revised to 5.5 ± 1.9 mm/yr. In total, the slip rate of the Sumatran Fault System at this latitude could be greater than the reliably constrained minimum slip rate of 7–14 mm/yr. Throughout the years, many destructive earthquakes have occurred as caused by the different segments of the Great Sumatran fault such as the
1943 Alahan Panjang earthquakes in the same region as the 1926 event, the
1994 Liwa earthquake from the Kumering segment in the south, the
1995 Kerinci earthquake from the Siulak segment, and the most recent event, the
March 2007 Sumatra earthquakes from the Toru segment. == Earthquake ==