Fiji is a group of volcanic islands in the South Pacific, lying about 4,450 kilometres (2,765 mi) southwest of Honolulu and 1,770 km (1,100 mi) north of New Zealand. Of the 332 islands and 522 smaller islets making up the archipelago, about 106 are permanently inhabited. The total land size is 18,272 km2 (7,055 sq mi). It has the 26th largest Exclusive Economic Zone of 1,282,978 km2 (495,361 sq mi).
The Ring of Fire is a region around much of the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur. The Ring of Fire is a horseshoe-shaped belt about 40,000 km (25,000 mi) long and up to about 500 km (310 mi) wide.
A convergent boundary is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a plane where many earthquakes occur, called the Wadati–Benioff zone. These collisions happen on scales of millions to tens of millions of years and can lead to volcanism, earthquakes, orogenesis, destruction of lithosphere, and deformation. Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere. The geologic features related to convergent boundaries vary depending on crust types.
Vanua Levu formerly known as Sandalwood Island, is the second largest island of Fiji. Located 64 kilometres to the north of the larger Viti Levu, the island has an area of 5,587.1 square kilometres (2,157.2 sq mi) and a population of 135,961 as of 2007.
Viti Levu is the largest island in the Republic of Fiji. It is the site of the nation's capital, Suva, and home to a large majority of Fiji's population.
The Cascadia subduction zone is a 960 km fault at a convergent plate boundary, about 112-160 km off the Pacific Shore, that stretches from northern Vancouver Island in Canada to Northern California in the United States. It is capable of producing 9.0+ magnitude earthquakes and tsunamis that could reach 30m. The Oregon Department of Emergency Management estimates shaking would last 5-7 minutes along the coast, with strength and intensity decreasing further from the epicenter. It is a very long, sloping subduction zone where the Explorer, Juan de Fuca, and Gorda plates move to the east and slide below the much larger mostly continental North American Plate. The zone varies in width and lies offshore beginning near Cape Mendocino, Northern California, passing through Oregon and Washington, and terminating at about Vancouver Island in British Columbia.
A submarine, undersea, or underwater earthquake is an earthquake that occurs underwater at the bottom of a body of water, especially an ocean. They are the leading cause of tsunamis. The magnitude can be measured scientifically by the use of the moment magnitude scale and the intensity can be assigned using the Mercalli intensity scale.
The 2000 New Ireland earthquakes occurred off the coast of New Ireland Province, Papua New Guinea on November 16 and 17.
The Philippine Fault System is a major inter-related system of geological faults throughout the whole of the Philippine Archipelago, primarily caused by tectonic forces compressing the Philippines into what geophysicists call the Philippine Mobile Belt. Some notable Philippine faults include the Guinayangan, Masbate and Leyte faults.
The 1906 Aleutian Islands earthquake occurred at 00:11 UTC on August 17. It had an estimated seismic moment of 3.8 x 1028 dyn cm−1, equivalent to a magnitude of 8.35 on the moment magnitude scale. This earthquake was followed thirty minutes later by the 1906 Valparaíso earthquake in Chile, but the two events are not thought to be linked. Due to the remote location, there are no reports of damage associated with this earthquake. A transpacific tsunami reported from Japan and Hawaii was triggered by the Chilean event, rather than the Aleutian Islands earthquake.
The 1917 Bali earthquake occurred at 06:50 local time on 21 January. It had an estimated magnitude of 6.6 on the surface wave magnitude scale and had a maximum perceived intensity of IX (Violent) on the Mercalli intensity scale. It caused widespread damage across Bali, particularly in the south of the island. It triggered many landslides, which caused 80% of the 1,500 casualties.
The 2013 Solomon Islands earthquake struck Temotu Province within Solomon Islands on 6 February with a moment magnitude of 8.0 and a maximum Mercalli intensity of VIII (Severe). The epicentre was close to the Santa Cruz Islands within Temotu Province at the boundaries of the Indo-Australian and Pacific tectonic plates, causing local evacuations, a tsunami of 11 m (36 ft) and killing at least nine people.
On 9 December 2016 at 4:38 a.m. local time, the Solomon Islands region was rocked by an Mww 7.8 earthquake, centered 30 km off San Cristobal Island, about 61 km southwest of Kirakira, the capital of Makira-Ulawa Province. Initially registering magnitude 8.0, later downgraded to 7.8, the temblor prompted tsunami warnings that kept countries surrounding the Coral, Tasman and Solomon Sea on high alert, but was later cancelled. A large aftershock of magnitude 6.9 occurred shortly afterwards. This earthquake was largely felt, waking many residents who later ran to high ground for fears of a potential tsunami. The earthquake killed a child and affected some 34,000 people in Makira, South Malaita and Guadalcanal Island where many had lost their homes or had no access to basic needs. Earthquakes are common in this region, with little or no fatalities. This earthquake is tied with three other magnitude 7.8 earthquakes for the second largest earthquake of 2016. On 17 December, the Solomon Islands would be rattled again by a 7.9 magnitude earthquake, this time 54 km east of Taron, Papua New Guinea.
The 2018 Fiji earthquakes occurred on August 19, at 00:19:40 UTC and on September 6 15:49 UTC. The epicenters were located close to the Fijian island Lakeba, and around 270 km from the small town of Levuka on Ovalau. The first earthquake registered a magnitude of Mww 8.2, and is the largest earthquake of 2018. It had a focal depth of 600 km, making it the second largest earthquake ever recorded at a depth greater than 300 km; a tie with the 1994 Bolivia earthquake, and behind the 2013 Okhotsk Sea earthquake. The initial earthquake was caused by a normal fault below the South Pacific Ocean. An Mww 7.9 event struck the islands again on September 6 at a depth of 670 km; this earthquake was a mainshock of its own. Both earthquakes may be considered a doublet event.
On July 17 2017, an earthquake struck near the Komandorski Islands, east of the Kamchatka Peninsula in the Bering Sea at. Although there were no casualties from this earthquake, it was notable for a rare characteristic known as supershear, and is one of the few times a large supershear earthquake has been observed. It was preceded by a few foreshocks months earlier, and aftershocks that continued for nearly six months.
The 1920 Xalapa earthquake was the deadliest in Mexico's history prior to 1985—killing at least 648 people. It occurred on January 3 at 22:25 local time, during a period of political unrest in the country. Mudflows and landslides triggered by the shock destroyed buildings in rural towns across the states of Veracruz and Puebla, causing most of the deaths. The earthquake was attributed to a shallow fault in the Trans-Mexican Volcanic Belt. It measured moment magnitude 6.3–6.4 and had a hypocenter depth of <15 km (9.3 mi). The Mexican government took immediate action in the aftermath—providing assistance and establishing communication services. Severely damaged towns including Xalapa were rebuilt, while others had to be abandoned. Help to survivors also came from civil society groups, civilians, and the Catholic Church. The earthquake's aftershocks were studied by scientists to determine its seismological characteristics.
The 2021 Kermadec Islands earthquakes were a series of earthquakes with magnitudes of 8.1 and 7.4 that occurred at 19:28:31 UTC on 4 March 2021. The epicentres were located southeast of Raoul Island in the Kermadec Islands, part of the New Zealand outlying islands. The main magnitude 8.1 earthquake was preceded by a magnitude 7.4 foreshock and followed by a magnitude 6.1 aftershock. A separate, unrelated magnitude 7.3 earthquake occurred off the coast of the North Island of New Zealand, approximately 900 km to the south, several hours before the main quakes. More than a dozen aftershocks exceeded magnitude 6.
On the morning of January 5, 1699, a violent earthquake rocked the then Dutch East Indies city of Batavia on the island of Java, now known as the Indonesian capital city of Jakarta. Dutch accounts of the event described the earthquake as being "so heavy and strong" and beyond comparable to other known earthquakes. This event was so large that it was felt throughout west Java, and southern Sumatra.
The Hunter Fracture Zone is a sinistral (left-lateral) faulting fracture zone. It is located to the south and southwest of Fiji and starts where the southern part of the New Hebrides Trench ends due to the increasing obliqueness of convergence lending to more strike slip faulting than subducting. It terminates around the International Date Line. It defines part of the plate boundary between the New Hebrides and the Conway Reef Microplate with the Australian Plate, with the rest of the convergence being accommodated by subduction and rifting.
The 1882 Panama earthquake occurred on September 7 at around 03:50 (UTC-5). The earthquake measured a magnitude between 7.9 and 8.3 on the surface-wave magnitude scale, making it the largest earthquake recorded in Panamanian history. It struck the San Blas Islands and was strongly felt in the City of Colón as well as the capital of Panama City. The earthquake also produced a major tsunami that had a maximum run-up of 3 meters. In total, the earthquake killed 250 people, 75 of which were from the tsunami. The earthquake and tsunami also halted the construction of the Panama Canal by a few months.
