The Matano fault is a major active WNW-ESE trending left lateral strike-slip fault on the island of Sulawesi. It extends for about 190 km from near the southern end of the Palu-Koro Fault in the west, to Kolono Bay on the east coast of the island. [1] [2]
The fault zone is subdivided into six main segments. From west to east, these are the Kuleana, Pewusai, Matano, Pamsoa, Ballawi and Geresa segments. [2] Lake Matano is formed as a pull-apart basin in a releasing stepover between the Pamsoa and Matano segments of the fault zone. The fault zone extends offshore to the east and may link to the Tolo Thrust and/or the South Sula Fault. [1]
Together with the Palu-Koro Fault, this fault zone forms part of the boundary between two of the major crustal blocks that form the island, the North Sula Block to the north and east and the Makassar Block to the south and west. The current slip rate along the Matano Fault is estimated to be in the range 17 to 28 millimetres (0.67 to 1.10 in) per year. [3] [1]
No earthquake has been recorded along the Matano fault zone for at least 200 years. Paleoseismic investigations on some of the segments have revealed evidence of past ruptures. Five faulting events have been detected along the easternmost Geresa segment of the fault, three in the last 1,000 years. The most recent is dated to between 1432 and 1819 with a rupture length of ~110 km and an estimated magnitude of ~7.4 Mw . The recurrence interval interpreted from these observations is 335±135 years, suggesting that a further rupture is likely due. [1]
This is a brief summary of the geology of Indonesia. Indonesia is located between two major tectonic plates, the Australian Plate and the newly-separated Sunda Plate.
The East Anatolian Fault is a ~700 km long major strike-slip fault zone running from eastern to south-central Turkey. It forms the transform type tectonic boundary between the Anatolian Plate and the northward-moving Arabian Plate. The difference in the relative motions of the two plates is manifest in the left lateral motion along the fault. The East and North Anatolian faults together accommodate the westward motion of the Anatolian Plate as it is squeezed out by the ongoing collision with the Eurasian Plate.
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The Awatere Fault is an active dextral strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone. The 1848 Marlborough earthquake was caused by rupture of the whole of the eastern section of the Awatere Fault.
The 1996 Biak earthquake, or the Irian Jaya earthquake, occurred on 17 February at 14:59:30 local time near Biak Island, Indonesia. The earthquake, which occurred on the New Guinea Trench, had a moment magnitude of 8.2 and a maximum Mercalli intensity of IX (Violent). The run-up height of the generated tsunami reached 7.7 m (25 ft). The disaster left at least 108 people dead, 423 injured, and 58 missing. It damaged or destroyed 5,043 houses which subsequently made another 10,000 homeless. At Korim, 187 houses were destroyed. Various countries and organizations provided aid and relief in the aftermath of the earthquake.
The 1968 Sulawesi earthquake struck Indonesia on August 14. It had a Richter magnitude of 7.4, spawned a large tsunami, and killed roughly 200 people.
On 28 September 2018, a shallow, large earthquake struck in the neck of the Minahasa Peninsula, Indonesia, with its epicentre located in the mountainous Donggala Regency, Central Sulawesi. The magnitude 7.5 quake was located 70 km (43 mi) away from the provincial capital Palu and was felt as far away as Samarinda on East Kalimantan and also in Tawau, Malaysia. This event was preceded by a sequence of foreshocks, the largest of which was a magnitude 6.1 tremor that occurred earlier that day.
The Palu-Koro Fault or Palu-Koro Fault System is a major active NNW-SSE trending left-lateral strike-slip fault zone on the island of Sulawesi in Indonesia. It caused the 2018 Sulawesi earthquake and tsunami.
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The western coast of West Sulawesi was struck by a major earthquake on 23 February 1969 at 00:36 UTC. It had a magnitude of 7.0 Mw and a maximum felt intensity of VIII on the Modified Mercalli intensity scale. It triggered a major tsunami that caused significant damage along the coast of the Makassar Strait. At least 64 people were killed, with possibly a further 600 deaths caused by the tsunami.
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An earthquake occurred 112 km, offshore, north of Maumere in the Flores Sea on December 14. The quake had a moment magnitude of 7.3 according to the United States Geological Survey (USGS). One person was killed and 173 others suffered injuries.
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The region of Ningxia was struck by a major earthquake on the morning of 14 October 1709. It had an estimated magnitude of 7.5 Ms and a maximum felt intensity of X (extreme) on the Modified Mercalli intensity scale. The city of Zhongwei was badly damaged, including a section of the Great Wall. A total of 2,032 people were killed.
The Keichō–Fushimi earthquake struck Japan on September 5, 1596. The earthquake measuring 7.5 ± 0.25 MJMA produced intense shaking across the Kansai region. Devastation was recorded in Kyoto and over 1,200 people perished.