The Lembang Fault (Indonesian: Sesar Lembang) is an active fault located 10 km north of the city of

Bandung Bandung is the capital city of the West Java province of Indonesia. Located on the island of Java, the city is the List of Indonesian cities by population, fourth-most populous city and fourth largest city in Indonesia after Jakarta, Surabay ...

on the

Indonesian Indonesian is anything of, from, or related to Indonesia, an archipelagic country in Southeast Asia. It may refer to: * Indonesians, citizens of Indonesia ** Native Indonesians, diverse groups of local inhabitants of the archipelago ** Indonesian ...

island of

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

. This sinistral slip fault is estimated to measure 29 km in length. While no historical earthquakes have occurred, the fault is thought to be possible of generating a magnitude () 6.5 to 7.0

earthquake An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they ...

in the future. Because of the potential for large and damaging earthquakes on the fault, the

Meteorology, Climatology and Geophysics Agency Meteorology, Climatology, and Geophysical Agency (, abbreviated BMKG) is an Indonesian non-departmental government agency for meteorology, climatology, and geophysics. History Its history began on 1841 with individual observation conducted by ...

(BMKG) has been monitoring activity on the fault.

Activity

Paleoseismic Paleoseismology is the study of ancient earthquakes using geologic evidence, such as geologic sediments and rocks. It is used to supplement seismic monitoring to calculate seismic hazard. Paleoseismology is usually restricted to geologic regim ...

trenching along the fault in a 2019 study uncovered three earthquakes in the 15th century, 2300–60 BCE and 19,620–19,140 BP with a recurrence interval of 170 to 670 years.

Threat

The

Indonesian Institute of Sciences The Indonesian Institute of Sciences (, or LIPI) was the governmental authority for science and research in Indonesia. It consisted of 47 research centers in the fields ranging from social to natural sciences. With the enactment of Presidential D ...

has urged that the Government of Indonesia educate the residents in nearby population centers about the dangers of a damaging earthquake on the fault. In 2019, the BMKG said that 22 seismic monitoring devices would be installed around that fault to monitor its activity and detect movements. Earthquakes can cause IDR 51 Trillion ($3.5 Billion) worth of damage, exceeding that of the

2004 Indian Ocean earthquake and tsunami On 26 December 2004, at 07:58:53 local time ( UTC+7), a major earthquake with a magnitude of 9.2–9.3 struck with an epicentre off the west coast of Aceh in northern Sumatra, Indonesia. The undersea megathrust earthquake, known in the sci ...

. It is estimated that around 2.5 million homes would be affected, including one million lightly damaged. Another million others seriously damaged and 500 thousand homes collapsed. An estimated four million would be displaced and 180,000 injured and 80,000 may be killed.

References

{{Reflist Seismic faults of Indonesia