The November 2022 Magnitude 7.0 Earthquake in the Solomon Islands

On 22 November 2022 at 02:03 local time, a magnitude 7.0 earthquake struck 18 km southwest of Malango in the Solomon Islands. The event originated at a shallow depth of 14 km, producing strong ground shaking across parts of Guadalcanal and nearby islands. According to records of strong earthquakes since 1 January 2000, this remains the only magnitude 7.0 or greater event in the immediate vicinity, occurring directly at the listed location. The Solomon Islands lie within a tectonically complex segment of the southwestern Pacific, where convergence between the Pacific Plate and the Australian Plate drives ongoing deformation. The islands form part of an intra-oceanic arc system characterized by rapid subduction, back-arc spreading, and strike-slip faulting. This setting produces frequent seismicity at shallow to intermediate depths, with the November 2022 event consistent with typical shallow thrust or reverse faulting along the plate interface or adjacent crustal structures. Historical seismic activity in the region reflects this dynamic environment. The arc has experienced multiple great earthquakes in the past century, often accompanied by tsunamis, yet the two-decade period leading to 2022 recorded no other magnitude 7.0 events within the immediate Malango area. The 2022 shock therefore stands as a notable occurrence within the modern instrumental catalog for that specific locale. Geological studies of the Solomon Islands arc highlight its youthful crust and active volcanism, with exposed ophiolitic sequences and coral reef terraces recording recent uplift. These features underscore the long-term effects of plate convergence at rates exceeding 10 cm per year in places. Shallow crustal earthquakes such as the 2022 event can contribute to incremental deformation and localized uplift along the forearc. Post-event assessments indicated limited structural damage and no significant tsunami generation, attributable to the moderate magnitude and focal depth. The Solomon Islands government and regional monitoring agencies continue to emphasize preparedness given the persistent seismic hazard posed by the surrounding plate boundaries.

References

USGS Earthquake Catalog (event parameters and historical listing since 2000).