The Fiji Seismology Unit has published its Earthquake Summary for December 2025, revealing that a total of 435 earthquakes were recorded within the month. Remarkably, the public only reported two felt tremors during this period.
The seismic activity varied in magnitude, ranging from a minimal 1.1 to a maximum of 5.7. Among the felt events, a notable magnitude 4.4 earthquake occurred on December 9, 2025, which was experienced in the Yasawas and parts of the Western Division, including Lautoka. The second felt tremor was stronger, recorded as a magnitude 5.7 on December 19, 2025, affecting areas in Vanua Levu and surrounding islands. This event led to a series of aftershocks, with the most significant measuring 4.4.
The Seismology Unit provided insight into the overall seismic landscape, highlighting a concentration of shallow earthquakes in northern Fiji, particularly around Vanua Levu, extending from the Yasawas to Cikobia Island along the Fiji Fracture Zone. The unit indicated that this level of activity is anticipated for the region due to its geological characteristics.
In addition to these events, deep earthquakes, found at depths between 300 to 600 kilometers, were primarily recorded east of Fiji, beneath the Lau Basin. This phenomenon reflects the ongoing subduction activity where the Pacific Plate moves beneath the Indo-Australian Plate.
Minor shallow seismic activity was also observed near Kadavu Island, southeast Viti Levu, and parts of Vanua Levu, particularly around Savusavu Bay. Additionally, the Seismology Unit noted a brief swarm of earthquakes near Naigani Island in Tailevu Province on December 7, with the strongest quake measuring 2.5; however, no felt reports emerged from this swarm.
The Fiji Seismology Unit reassured residents that such seismic activity levels are typical for Fiji, given the country’s positioning along busy tectonic boundaries. They urged the public to stay informed and prepared through official updates, underscoring the importance of being ready for natural events in this earthquake-prone region.