2024 East Sepik earthquake

The island of New Guinea lies within the complex zone of collision between the Australian and Pacific plates. Within this overall setting, the active tectonics of northern Papua New Guinea is dominated by the effects of continuing collision between the Huon–Finisterre island arc terrane with the edge of the Australian continental margin. The overall shortening is focused into two zones of thrust faulting, the Ramu–Markham fault zone, which forms the southwestern boundary of the Huon–Finisterre terrane, and the Highlands Thrust Belt, which lies further southwest and deforms the Australian margin.^[3]

In April 2023, a magnitude 7.1 earthquake 21 km (13 mi) southeast of the March 2024 event killed eight people.^[4][5]

The earthquake occurred at 06:22:04 PGT (20:22 UTC), with an epicenter located 4 km (2.5 mi) north of Chambri Lake, or 36 km (22 mi) east-northeast of Ambunti. It also had a hypocenter 41.5 km (25.8 mi) deep. It had a maximum Modified Mercalli intensity of VII (Very Strong), and according to the PAGER service of the United States Geological Survey, shaking of intensities VI-VII (Strong-Very Strong) was felt by an estimated 487,000 residents in East Sepik and Sandaun Provinces.^[1] Tremors were also felt in Madang Province^[2] and in Goroka, Eastern Highlands Province.^[6]

The earthquake killed five people, injured 12 others^[7] and destroyed around 1,000 homes.^[8] East Sepik provincial police commander Christopher Tamari warned that the death toll could rise as emergency teams were trying to reach remote areas.^[9] Two of the deaths occurred in Angoram^[10] and another died in Gawi.^[11] Many more unconfirmed fatalities were reported in remote villages near the epicenter.^[12] At the time of the earthquake, the province was affected by severe flooding along the Sepik River, which exacerbated damage and casualties from the earthquake. Most houses in the area were made of wood and thatched roofing.^[13] Many residents were unable to flee when the earthquake struck, as the inundation reached the chest level in some areas. In the village of Sotmeri, which was experiencing major flooding at the time of the earthquake, all 45 houses collapsed,^[14] killing a three-year-old child who drowned after being pinned down by debris when their residence collapsed into floodwaters,^[11] while 50 houses were destroyed in the neighbouring village of Korogu.^[14] Fishermen out in the water said that waves started building up in rivers when the earthquake struck.^[14]

At Kamanibit village in Angoram District, 39 houses collapsed and were submerged beneath floodwaters,^[15] while another 11 houses collapsed in the nearby village of Jikinumbu, killing a seven-year-old girl and her mother.^[13] Thirty-five houses collapsed in Kawarari.^[16] In Yenjimangua, seven houses were destroyed while in Niaurange, eight houses collapsed into floodwaters.^[17] A landslide occurred in Yangoru-Saussia District, burying several gardens.^[18] In Maprik District, six casualties were recorded from Maprik town and two from Yangoru.^[14] A high school in the district was also damaged, while in Wewak, two oxygen cylinders at the Boram General Hospital exploded during the earthquake. A bridge connecting the town to the Papua New Guinea Defence Force garrison at Moem Barracks also collapsed.^[13]

Allan Bird, the governor of East Sepik, said that the earthquake had "damaged most parts of the province",^[13] with the worst affected areas being Angoram, Wosera-Gawi and Ambunti-Dreikikier Districts, as well as areas along the Sepik River and wetlands.^[19] The International Organization for Migration estimated that the earthquake and preceding floods displaced about 10,000 people and affected 400,000 others in East Sepik and Highlands Region, and left more than 1,000 houses destroyed.^[20] Eighty-six schools in Ambunti, Wosera-Gawi and Angoram suspended classes indefinitely due to the effects of the earthquake and floods.^[21]