1979 Yapen earthquake

Earthquake in Papua Province, Indonesia 1979 Yapen earthquake 1979-09-12 05:17:51 usp00012wp 658645 Indonesia Papua#Indonesia September 12, 1979 14:17:51 WIT (Indonesia Eastern Standard Time) 7.5 w y7.9 s y 20 km mi 0 on -1.679 136.94 region:ID_type:event inline,title Strike-slip 8 2 m on 115 killed The 1979 Yapen earthquake occurred on September 12 at 05:17:51 UTC. It had an epicenter near the coast of Yapen Island in Irian Jaya, Indonesia. Measuring 7.5 on the moment magnitude scale and having a depth of 20 km, it caused severe damage on the island. At least 115 were killed due to shaking and a moderate tsunami. Tectonic setting The northern coast of New Guinea is situated in a region of east–west oblique plate convergence between the Australian and Pacific plates. The oceanic crust of the Pacific plate subducts obliquely beneath New Guinea and nearby islands along the New Britain Trench and Manokwari Trough.Tregoning P. Gorbatov A. Evidence for active subduction at the New Guinea Trench Geophysical Research Letters 2004 31 13 10.1029/2004GL020190 2004GeoRL..3113608T 26940540 free A large component of this oblique convergence is accommodated by east–west left-lateral shear at a rate of 80 mm/yr. The shear zone is approximately 300 km long and is a complex zone of faults. The Sorong, Koor, Ransiki and Yapen faults are the largest structures forming the shear zone.Watkinson Ian M. Hall Robert Fault systems of the eastern Indonesian triple junction: evaluation of Quaternary activity and implications for seismic hazards Geological Society, London, Special Publications 2016 441 1 71–120 10.1144/SP441.8 2017GSLSP.441...71W 132297395 https://pure.royalholloway.ac.uk/portal/files/29857358/Watkinson_and_Hall_accepted.pdf Earthquake The earthquake occurred due to left-lateral strike-slip faulting on the 420 km long Yapen Fault. The Yapen Fault is the fastest-slipping fault in the shear zone, estimated to move at a rate of 46 ± 12 mm/yr. It crosses east–west through Cenderawasih Bay. Seismologist Emile A. Okal estimated that the rupture produced up to 2 m of displacement on an east-southeast–west-northwest fault. The total rupture length was 75 km × 35 km. A study in 2002 estimated the rupture to be 80 km × 15 km and producing up to 7 m of slip.Henry C. Das S. The Mw 8.2, 17 February 1996 Biak, Indonesia, earthquake: Rupture history, aftershocks, and fault plane properties Journal of Geophysical Research 2002 107 B11 ESE 11-1-ESE 11–16 10.1029/2001JB000796 2002JGRB..107.2312H https://www.earth.ox.ac.uk/~johne/teaching/pdfs/henry-das02.pdf It was followed by an aftershock sequence trending east–west.Seno Tetsuzo Kaplan David E. Seismotectonics of western New Guinea Journal of Physics of the Earth 1988 36 3 107–124 10.4294/jpe1952.36.107 https://www.researchgate.net/publication/270804736 free A cluster of aftershocks occurred north of the mainshock, at Pandaidori, displayed reverse faulting. This aftershock sequence is thought to be triggered by stress transfer. Damage Shaking from the mainshock killed 15 people and demolished at least 1,000 homes. Despite being a strike-slip earthquake, slip of up to 2 m was sufficient to generate a moderate tsunami near the coastline. Waves measuring 2 m was recorded at Biak. The tsunami killed at least 100 people on Yapen Island. A fisherman on Biak was among the fatalities after being swept away by the waves. In West Yapen District, 76 homes were destroyed and flooded by the tsunami. Many residents had to hold themselves onto stable objects during the shaking. Ground cracks occurred. Many churches and homes collapsed. In two villages, all homes were destroyed. A large fissure up to 1.5 km was reported in Serui. In Menawi, 254 homes were seriously damaged. A further 90 homes and a school were destroyed at Randawaya II.Retia Kartika Dewi Rizal Setyo Nugroho Hari Ini dalam Sejarah: Gempa Yapen, Papua 8,1 M, 16.500 Warga Kehilangan Rumah Today in History: Yapen Earthquake, Papua 8.1 M, 16,500 Residents Lost Their Homes https://www.kompas.com/tren/read/2020/09/12/092055165/hari-ini-dalam-sejarah-gempa-yapen-papua-81-m-16500-warga-kehilangan-rumah?page=all 17 June 2022 Kompas 12 September 2020 id After the earthquake, local government officials in Jayapura were not notified about the earthquake due to a local event. It was only after news was transmitted to Garuda Indonesia in Sentani were they informed. The Indonesian Minister of Home Affairs appointed the Governor of Irian Jaya to respond immediately to the affected area. A total of 16,500 residents were displaced. See also List of earthquakes in 1979 List of earthquakes in Indonesia References M 7.9 – 55 km S of Biak, Indonesia https://earthquake.usgs.gov/earthquakes/eventpage/usp00012wp/executive United States Geological Survey 17 June 2022 ISC-GEM Global Instrumental Earthquake Catalogue (1904–2018) http://www.isc.ac.uk/iscgem/index.php ISC 2022 International Seismological Centre Version 9.0 10.31905/D808B825 free Katalog Gempabumi Signifikan dan Dirasakan https://www.bmkg.go.id/gempabumi/katalog-gempabumi-signifikan.bmkg Meteorology, Climatology, and Geophysical Agency 11 August 2021 25 July 2021 https://web.archive.org/web/20210725043658/https://www.bmkg.go.id/gempabumi/katalog-gempabumi-signifikan.bmkg dead Historical Seismicity and Seismotectonic Context of the Great 1979 Yapen and 1996 Biak, Irian Jaya Earthquakes http://www.earth.northwestern.edu/people/emile/PDF/EAO118.pdf E. Okalyear=1999 Pure and Applied Geophysics 1999 154 3–4 10.1007/s000240050247 633–675 1999PApGe.154..633O 128554047 https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-more-info/4842 Significant Earthquake Information National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information 1972 NOAA National Centers for Environmental Information 10.7289/V5TD9V7K 10 June 2022 Data Set Global Historical Tsunami Database National Geophysical Data Center / World Data Service (NGDC/WDS) https://www.ngdc.noaa.gov/hazel/view/hazards/tsunami/event-more-info/2119 10.7289/V5PN93H7 NOAA National Centers for Environmental Information Data Set 10 June 2022 External links 947787 Category:1979 earthquakes Earthquake Category:Yapen Islands Category:Tsunamis in Indonesia Category:1979 in Indonesia Category:Papua (province) Category:Schouten Islands Category:Earthquakes in Western New Guinea Category:1970s tsunamis Category:Strike-slip earthquakes