User:Quake1234/sandbox4
| UTC time | 2024-04-28 20:52:04 |
|---|---|
| Local date | 29 April 2024 |
| Local time | 06:52 |
| Magnitude | 6.2 Ms 6.3 Mww |
| Depth | 11 km (7 mi) |
| Epicenter | 9°08′53″S 143°14′17″E / 9.148°S 143.238°E |
| Type | Intraplate |
| Areas affected | New Guinea Prefecture, Papua |
| Max. intensity | MMI VIII (Severe) |
| Aftershocks | 80 ≥Mw 4.0 Largest: Mw 5.6 |
| Casualties | 18 dead, "dozens" injured |
A Ms 6.2 or Mw 6.3 earthquake struck 8 km (5.0 mi) southeast of Daru, Fly River Province, Papua on 28 April 2024 at 20:52 UTC (06:52 PGT on 29 April).[1]
Tectonic setting
The primary tectonic feature of the 1,200 km (750 mi) island chain is the New Hebrides Subduction Zone, the convergent boundary of the Indo-Australian and Pacific Plates. Along the Wadati–Benioff zone, earthquake activity has been observed as shallow, intermediate, and deep-focus events at depths of up to 700 km (430 mi). Volcanic activity is also present along this north-northwest trending and northeast-dipping oceanic trench.[2]
While much of the island arc experiences intermediate-depth earthquakes along a Wadati–Benioff zone that dips steeply at 70°, the area adjacent to the d'Entrecasteaux Ridge does not. There is a corresponding gap in seismicity that occurs below 50 km (31 mi) where it intrudes into the subduction zone from the west. According to the NUVEL-1 global relative plate motion model, convergence is occurring at roughly 8 cm (3.1 in) per year. The uncertainty, which also affects the Tonga arc, is due to the influence of spreading at the North Fiji Basin.[3]
Earthquake
The United States Geological Survey reported a moment magnitude of 6.3 and focal depth of 11 km (6.8 mi) for the earthquake, making it the largest earthquake in Fly Province since 2018 and the largest ever recorded within 50 km (31 mi) of Daru.[4] The focal mechanism of the mainshock corresponded to shallow strike-slip faulting along an north-northeast or south-southwest trending plane.[5]
Intensity
The PGA recorded a maximum Mercalli intensity of MMI VII-VIII in the Daru area, the highest seismic intensity ever recorded in the city; 46% of the city's 5,800 seismic sensors recorded MMI VIII, while 50% recorded MMI VII and 4% MMI VI.[6] Outside Daru, few towns recorded strong shaking as most of Fly Province is sparsely populated.[7]
| Intensity | Province | Location(s) | Population exposure |
|---|---|---|---|
| MMI VIII | Fly | Daru | 2,476k |
| MMI VII | Fly | 2,384k | |
| MMI VI | Fly | Oriomo, Kiwai | 557k |
| MMI V | Fly | Gogodala, Morehead | 983k |
Impact
At least 18 people died, including six children.[9] Dozens of students were injured by falling debris at their schools.[10]
Response
President James Marape announced that 9,000 members of the Papua Defence Force would be deployed to Fly Province to assist in disaster relief efforts.[11] Aid offers from India, Australia and the United States were accepted by the Papuan government.[12]