1992 Flores earthquake and tsunami

Destructive tectonic event in Indonesia August 2025 1992 Flores earthquake and tsunami 1992-12-12 05:29:26 usp0005j5a 257091 1992 12 12 yes 13:29 WITA (Indonesia Central Standard Time) Indonesia Flores#Indonesia 7.7 w y 27.7 km on 8.480 S 121.896 E inline,titleSignificant Earthquakes of the World https://earthquake.usgs.gov/eqcenter/eqarchives/significant/sig_1992.php USGS August 9, 2025 https://web.archive.org/web/20090912001941/http://earthquake.usgs.gov/eqcenter/eqarchives/significant/sig_1992.php September 12, 2009 July 16, 2008 dead Yes (26 m ft on) IXhttps://content.bmkg.go.id/wp-content/uploads/Katalog-Gempabumi-Merusak-1821-2024.pdf BMKG August 15, 2025 Katalog Gempabumi Signifikan & Merusak id https://web.archive.org/web/20250810052927/https://content.bmkg.go.id/wp-content/uploads/Katalog-Gempabumi-Merusak-1821-2024.pdf 10 August 2025 Flores Indonesia 2,080 – 2,500 dead 500 – 2,144 injured 1.086 ghttps://earthquake.usgs.gov/earthquakes/eventpage/usp0005j5a/map?shakemap-code=usp0005j5a&shakemap-source=atlas&shakemap-pga=true&shakemap-stations=true&shakemap-mmi-contours=false M 7.8 - 37 km WNW of Maumere, Indonesia earthquake.usgs.gov USGS 2025-04-27 116.03 cm/s yes 6.1 b yM 6.1 - 33 km WNW of Maumere, Indonesia https://earthquake.usgs.gov/earthquakes/eventpage/usp0005j5f/executive earthquakes.usgs.gov USGS August 13, 2025 The 1992 Flores earthquake and tsunami occurred on 12 December on the island of Flores in Indonesia. With a magnitude of 7.7 and a maximum Mercalli intensity of IX (Violent), it was the largest and the deadliest earthquake in 1992 and in the Lesser Sunda Islands region, with at least 2,500 people killed. The earthquake generated an unusually large tsunami for its size; a submarine landslide may explain this phenomenon. Submarine rockfall was observed near the site of the earthquake. Observed runups (height above normal sea level) were mostly around 3 – 4 m on, with higher runups on Babi Island, Bou-Tanabeten, and Riangkroko village. The earthquake was caused by slip on the Flores Thrust fault. This fault dips to the south underneath Flores Island, and is part of the back-arc thrust of Indonesia. The epicenters of most earthquakes on the Flores Thrust are on Flores Island. The area often experiences large earthquakes, with multiple impacting the area since 1992, such as the 2018 Lombok earthquakes, which were produced by the Flores thrust. The Flores thrust itself has produced at least six tsunamigenic earthquakes since 1800. Tectonic setting alt=Several islands are visible, forming a map of southern Indonesia. Lines are drawn parallel to the island, indicating differing levels of slab depth.|thumb|A tectonic map of the Java area and areas further east.Indonesia lies on the Pacific Ring of Fire, an area of significant volcanic and tectonic activity. The archipelago is located between the Eurasian, Pacific and Australian tectonic plates.18 March 2011 RI sits on Pacific 'ring of fire' : official https://en.antaranews.com/news/69302/ri-sits-on-pacific-ring-of-fire--official live https://web.archive.org/web/20180806145803/https://en.antaranews.com/news/69302/ri-sits-on-pacific-ring-of-fire--official 6 August 2018 6 August 2018 Antara News The Flores area in particular contains both strike-slip faults and thrust faults.Handayani Lina Proceedings of the Proceedings of the 7th Mathematics, Science, and Computer Science Education International Seminar, MSCEIS 2019, 12 October 2019, Bandung, West Java, Indonesia 2020 978-1-63190-256-7 1 Seismic Hazard Analysis of Maumere, Flores: a Review of the Earthquake Sources 10.4108/eai.12-10-2019.2296247 April 1, 2025 https://eudl.eu/pdf/10.4108/eai.12-10-2019.2296247 The Flores backthrust is north of the island arc of Indonesia, and is formed by the subduction of the Indo-Australian plate underneath the Eurasian plate west of Lombok while being formed by the Australian plate and Banda Arc south of Rote Island.Xiaodong Yang Singh Satish Tripathi Anand January 6, 2020 Did the Flores backarc thrust rupture offshore during the 2018 Lombok earthquake sequence in Indonesia? https://academic.oup.com/gji/article/221/2/758/5757908 Geophysical Journal International 221 2 758–759 10.1093/gji/ggaa018 free 2024-02-12 subscription It is characterized by intermediate-depth down-dip subduction.Eric S. Jones Gavin P. Hayes Melissa Bernardino Fransiska K. Dannemann Kevin P. Furlong Harley M. Benz Antonio Villaseñor June 30, 2014 USGS Open-File Report 2010–1083-N: Seismicity of the Earth 1900–2012 Java and Vicinity https://pubs.usgs.gov/of/2010/1083/n/ 2025-03-30 pubs.usgs.gov It is a part of the larger backthrust of the back-arc region of Indonesia. Earlier marine geophysical studies have suggested that the back-arc backthrust consists of two regions: the Wetar thrust and the Flores thrust. However, newer research suggests that the whole thrust is continuous, spanning a distance of about 2000 km mi on. The Sunda and Australian plates converge at a rate of 80 mm/yr, in which the Sunda megathrust takes 70 mm/yr of the movement. The remaining 10 mm/yr rate is accommodated by the Flores back-arc thrust. It runs off the north coast of the Lesser Sunda Islands, in the Banda Sea.Sarjan Achmad Nugraha Andri 1 22 April 2021 Delineation of Upper Crustal Structure Beneath the Island of Lombok, Indonesia, Using Ambient Seismic Noise Tomography https://dr.ntu.edu.sg/bitstream/10356/151064/2/feart-09-560428.pdf Frontiers in Earth Science 9 2 560428 2021FrEaS...9..269S 10.3389/feart.2021.560428 16 October 2021 free 16 October 2021 https://web.archive.org/web/20211016052732/https://dr.ntu.edu.sg/bitstream/10356/151064/2/feart-09-560428.pdf dead The area is seismically active, with 79 earthquakes larger than w6.0 recorded in the area between 1900 and 2022. Eleven of those quakes generated tsunamis.Citrosiswoyo Wahyudi Mulyadi Yeyes 1 July 2024 Numerical Modelling of the Potential Hazard Due to Future Flores Back Arc Thrust Earthquake Generated Tsunami https://www.researchgate.net/publication/382708658 April 6, 2025 ResearchGate 2 In addition, the area has generated at least six tsunamigenic quakes of s>=6.5 since 1800.Felix Raquel P. Hubbard Judith A. Bradley Kyle E. Lythgoe Karen H. Li Linlin Switzer Adam D. 2022-05-18 Tsunami hazard in Lombok and Bali, Indonesia, due to the Flores back-arc thrust https://nhess.copernicus.org/articles/22/1665/2022/ Natural Hazards and Earth System Sciences English 22 5 1665–1682 2022NHESS..22.1665F 10.5194/nhess-22-1665-2022 1561-8633 March 31, 2025 free 20.500.11820/4c931103-5dc4-462f-b358-9daf214ddb61 free There exists substantial tsunami risk associated with the back-arc thrust of Indonesia. The lesser-studied eastern part of Indonesia has been hit by more tsunamis than the more-studied western part.Pranantyo Ignatius Heidarzadeh Mohammad Cummins Phil May 2021 Complex tsunami hazards in eastern Indonesia from seismic and non-seismic sources: Deterministic modelling based on historical and modern data https://www.researchgate.net/publication/351374631 ResearchGate March 31, 2025 Despite back-arc thrust tsunamis not being as common as megathrust tsunamis, they can still inflict severe damage. The eastern segment of the Flores thrust ruptured in the 1992 Flores earthquake, while the western segment has remained intact. However, the only instrumentally recorded quake caused by the Flores thrust was the 1992 quake. Earthquake The earthquake was the result of shallow thrust faulting along a fault located in the back-arc region between the Sunda and Banda island arcs. The Flores Thrust represents a back-arc thrust fault that accommodated tectonic deformation between the Australian and Sunda plates. This structure runs for over 1,500 km. Its eastern segment was responsible for producing the earthquake.Felix Raquel P. Hubbard Judith A. Bradley Kyle E. Lythgoe Karen H. Li Linlin Switzer Adam D. Tsunami hazard in Lombok and Bali, Indonesia, due to the Flores back-arc thrust Nat. Hazards Earth Syst. Sci. 2022 22 5 1665–1682 10.5194/nhess-22-1665-2022 free 2022NHESS..22.1665F 20.500.11820/4c931103-5dc4-462f-b358-9daf214ddb61 free The earthquake occurred at 05:29 UTC and was followed by several serious aftershocks.December 12, 1992 Indonesia Earthquake Dec 1992 UN DHA Situation Reports 1 - 9 https://reliefweb.int/report/indonesia/indonesia-earthquake-dec-1992-un-dha-situation-reports-1-9?OpenDocument= August 9, 2025 Reliefweb Department of Humanitarian Affairs Extensive soil liquefaction was observed along the Flores Sea, including in the Maumere Port, where it caused "extensive damage".December 28, 1992 Preliminary Report - Flores Island, Indonesia Earthquake of December 12, 1992 https://openjicareport.jica.go.jp/pdf/11143419_05.pdf August 13, 2025 Japan International Cooperation Agency A peak ground acceleration of 1.0860 g and a peak ground velocity of 116.03 cm/s were observed. In total, 102Jufriansah Adi Khusnani Azmi Pramudya Yudhiakto Afriyanto Mulya March 27, 2023 Comparison of aftershock behavior of the flores sea 12 december 1992 and 14 december 2021 https://www.researchgate.net/publication/377456099 Journal of Physics: Theories and Applications 7 1 65–74 10.20961/jphystheor-appl.v7i1.71609 free – 148March 24, 1993 Indonesia Flores Earthquake Reconstruction Project https://documents1.worldbank.org/curated/en/263861468039852272/pdf/multi-page.pdf April 1, 2025 World Bank 7 aftershocks with magnitudes above w3.0 were recorded. The largest recorded aftershock was rated b6.1. It has been estimated that a 140 x 40 km on area with two major slip regions was ruptured in the quake.Pranantyo Ignatius Cummins Phil July 2019 Multi-Data-Type Source Estimation for the 1992 Flores Earthquake and Tsunami https://www.researchgate.net/publication/330117953 April 1, 2025 ResearchGate 11 Tsunami alt=Large amounts of dead, dry branches are seen on a dry, sandy surface. There are green palm trees everywhere in the background.|thumb|Damage caused by the tsunami The tsunami was reported to have arrived within five minutes of the earthquake. Wave run-up heights of 3–4 m occurred along the eastern coast of Maumere. The maximum run-up height was measured at Riangkroko village at 26 m; the tsunami killed 137 villagers. Located along the Nipah River, the tsunami traveled 600 m inland. It washed away the whole village and stripped away coconut trees, leaving only roots. In another village 6 km north, Bou-Tanabeten, the tsunami run-up was 12 m. Along other locations hit by tsunamis on Flores Island, most trees remained standing. At Wuhring, a village 5 km from Maumere, 3 m waves swept through the village and killed 100 people. On Babi Island, the tsunami left human remains hanging on trees; 263 deaths occurred on the island, representing nearly a quarter of the island's population, and two villages were badly damaged. The maximum run-up on the island was recorded at 7.3 m. Wave reflection off Flores Island may have partly contributed to the tsunami's destructive effects on Babi Island.Yeh Harry Imamura Fumihiko Synolakis Costas Tsuji Yoshinobu Liu Philip Shi Shaozhong 1993 The Flores Island tsunamis Eos 74 33 369–373 1993EOSTr..74..369Y 10.1029/93EO00381 Babi Island was likely inundated by two separate tsunami episodes.Minoura K. Imamura F. Takahashi T. Shuto N. 1997-06-01 Sequence of sedimentation processes caused by the 1992 Flores tsunami: Evidence from Babi Island https://doi.org/10.1130/0091-7613(1997)0252.3.CO;2 Geology 25 6 523–526 10.1130/0091-7613(1997)025<0523:SOSPCB>2.3.CO;2 1997Geo....25..523M 0091-7613 subscription The earthquake produced the deadliest and largest tsunami in the Flores Sea area in modern history. The tsunami has been described as having "enormous size", suggesting a potential submarine landslide.12 December 1992, Mw 7.7, Flores, Indonesia - International Tsunami Information Center https://legacy.itic.ioc-unesco.org/legacy.itic.ioc-unesco.org/indexecb6.html?option=com_content&view=article&id=1101&Itemid=3127 2025-04-01 legacy.itic.ioc-unesco.org Major subaqueous slumping was observed near Leworaharag. In addition, there exists evidence of a submarine landslide or rockslide caused by the earthquake. Seismic stratigraphy was used to identify two areas of submarine rockfall likely caused by the earthquake.Budioni Kris Submarine Lanslides On The Sea Bottom Of Maumere Bay, Flores, Based On The Interpretation Of Seismic Reflection Records https://www.iagi.or.id/web/digital/17/SUBMARINE-LANDSLIDES-ON-THE-SEA-BOTTOM-OF-MAUMERE-BAY,-FLORES,-BASED-ON-THE-INTERPRETATION-OF-SEISMIC-REFLECTION-RECORDS.pdf April 1, 2025 IAGI 369 Submarine landslide-induced tsunamis have occurred in the past in Indonesia, with one notable example being the 1674 Ambon earthquake and megatsunami.Khusnani Azmi Jufriansah Adi Thalo Ota September 30, 2023 Tsunami event in Flores: literature review https://jurnal.uns.ac.id/jphystheor-appl/article/download/74625/42251 Journal of Physics: Theories and Applications 7 2 139–151 10.20961/jphystheor-appl.v7i2.74625 free Aftermath and relief efforts At least 2,500 people were killed or went missing near Flores, including 1,490 at Maumere and 700 on Babi. More than 500 people were injured and 90,000 were left homeless. 30,000 homes were destroyed in the earthquake.NCEI Hazard Earthquake Information https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-more-info/5343 April 1, 2025 NCEI 19 people were killed and 130 houses were destroyed on Kalaotoa. Damage was assessed at approximately US$100 million. Approximately 90% of the buildings were destroyed at Maumere, the hardest-hit town, by the earthquake and ensuing tsunami while 50% to 80% of the structures on Flores were damaged or destroyed. Electricity in the general area and the port of Maumere was shut down. Maumere's hospital was completely destroyed, and patients were treated in tents. Damage also occurred on Sumba and Alor. The Indonesian government sent rescue and relief missions to earthquake-stricken areas and declared the earthquake a national disaster through Presidential Decree (Keppres) Number 66 of 1992, due to its widespread impact and the need for cross-ministerial response and international assistance.Kriteria Penetapan Status Bencana Nasional di Indonesia dan Riwayatnya https://democrazy.id/kriteria-penetapan-status-bencana-nasional-di-indonesia-dan-riwayatnya/ DEMOCRAZY.ID 2025-11-30 2025-11-30 id The Indonesian Air Force provided assistance, mostly transporting medicine and clothing. Malaria and influenza rose significantly after the disaster. Babi Island survivors were evacuated since all the houses on the island were destroyed. International relief efforts were hindered by the onset of the rainy season. The Indonesian government also requested assistance from the international community. Agencies such as the Asian Development Bank, along with the World Bank, the Australian Agency for International Development, the Japanese Overseas Cooperation Fund, and others, made a coordinated effort to support reconstruction.October 2000 Project Performance Audit Report on the Flores Emergency Reconstruction Project (Loan 1241-INO[SF]) in Indonesia https://www.adb.org/sites/default/files/evaluation-document/35256/files/pe552.pdf August 9, 2025 Asian Development Bank See also 5 August 2018 Lombok earthquake 2026 Flores earthquake List of earthquakes in 1992 List of earthquakes in Indonesia References External links 257091 Flores Flores Category:Earthquakes in Indonesia Category:Geography of Flores Island (Indonesia) Category:Tsunamis in Indonesia Category:December 1992 in Indonesia Category:East Nusa Tenggara Category:1992 disasters in Indonesia Category:Flores (Indonesia)