Seismic Activity Around Kokopo, Papua New Guinea

The M7.5 earthquake of 29 March 2015 struck 53 km southeast of Kokopo at 23:48 local time, at a focal depth of 41 km. This event forms part of a sequence of strong shocks that have repeatedly affected the region since 2000. Kokopo lies on the northeastern tip of New Britain within the Bismarck Archipelago. The area occupies a complex plate-boundary zone where the Solomon Sea Plate subducts beneath the South Bismarck Plate. Rapid convergence, combined with strike-slip faulting along the Bismarck Sea seismic lineation, produces frequent moderate-to-large earthquakes at shallow to intermediate depths. The subduction interface and overlying crustal faults both contribute to the observed seismicity. Since 1 January 2000, four earthquakes of magnitude 7.5 or greater have occurred within 100 km of Kokopo. On 16 November 2000 an M8.0 event, known as the 2000 New Ireland earthquake, nucleated 94 km from the 2015 epicenter. The same day an M7.8 shock was recorded 81 km away. The M7.5 of 29 March 2015 occurred at the reference location itself. Most recently, an M7.6 earthquake struck 75 km northeast of Kokopo on 14 May 2019. These events illustrate the persistent seismic hazard associated with the regional plate-boundary system. Historical records and instrumental catalogs confirm that the Kokopo–Rabaul area experiences recurrent strong shaking. The combination of thrust and strike-slip mechanisms, together with the proximity of population centers to active faults, sustains elevated risk. Continued monitoring by regional seismic networks remains essential for understanding rupture patterns and improving hazard assessments. References
USGS Earthquake Catalog (events 2000–2019)
Global CMT Catalog
Geological Survey of Papua New Guinea seismic bulletins