The epicenter, epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.
The Peru–Chile Trench, also known as the Atacama Trench, is an oceanic trench in the eastern Pacific Ocean, about 160 kilometres (99 mi) off the coast of Peru and Chile. It reaches a maximum depth of 8,065 m (26,460 ft) below sea level in Richards Deep and is approximately 5,900 km (3,666 mi) long; its mean width is 64 km (40 mi) and it covers an expanse of some 590,000 km2 (230,000 sq mi).
Many major earthquakes have occurred in the region of the Kamchatka Peninsula in far eastern Russia. Events in 1737, 1923 and 1952, were megathrust earthquakes and caused tsunamis. There are many more earthquakes and tsunamis originating from the region.
The 2001 southern Peru earthquake occurred at 20:33:15 UTC on June 23 with a moment magnitude of 8.4 and a maximum Mercalli intensity of VIII (Severe). The quake affected the Peruvian regions of Arequipa, Moquegua and Tacna. It was the most devastating earthquake in Peru since the catastrophic 1970 Ancash earthquake and globally the largest earthquake since the 1965 Rat Islands earthquake.
The 2006 Kīholo Bay earthquake occurred on October 15 at with a magnitude of 6.7 and a maximum Mercalli intensity of VIII (Severe). The shock was centered 21 kilometers (13 mi) southwest of Puakō and 21 km (13 mi) north of Kailua-Kona, Hawaiʻi, just offshore of the Kona Airport, at a depth of 38.2 km (23.7 mi). It produced several aftershocks, including one that measured a magnitude of 6.1 seven minutes after the main shock. The Pacific Tsunami Warning Center measured a nondestructive tsunami of 4 in (100 mm) on the coast of the Big Island.
The 2008 Peloponnese earthquake killed two people, injured more than 220 and left at least 2,000 people homeless in north western Peloponnese, Greece, on June 8. The earthquake hit the area at 1525 EET, with a moment magnitude of 6.5, according to the Athens Geodynamic Institute. It was strongly felt as far away as in Athens and in parts of southern Italy. The US Geological Survey reported that the quake had a magnitude of 6.4. The epicenter of the tremor was located about 15 miles (32 km) southwest of the Greek port city of Patras, at a depth of 16 km. Interior Minister Prokopis Pavlopoulos dispatched rescue and recovery teams, the Red Cross and units of the army in order to assess the damage and the needs of survivors in the earthquake affected areas.
A deep-focus earthquake in seismology is an earthquake with a hypocenter depth exceeding 300 km. They occur almost exclusively at convergent boundaries in association with subducted oceanic lithosphere. They occur along a dipping tabular zone beneath the subduction zone known as the Wadati–Benioff zone.
The 2013 Okhotsk Sea earthquake occurred with a moment magnitude of 8.3 at 15:44:49 local time on 24 May. It had an epicenter in the Sea of Okhotsk and affected primarily Asian Russia, especially the Kamchatka Peninsula where the shaking lasted for five minutes.
An earthquake measuring 8.0 struck Peru and the surrounding areas on 26 May 2019 at 02:41 local time. It had a maximum perceived intensity of VII on the Modified Mercalli intensity scale in the towns of Yurimaguas and Lagunas. Two people died and a further 30 were injured. It was the strongest earthquake in 2019 by magnitude.
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.
The 2013 Craig, Alaska earthquake struck on January 5, at 12:58 am (UTC–7) near the city of Craig and Hydaburg, on Prince of Wales Island. The Mw 7.5 earthquake came nearly three months after an Mw 7.8 quake struck Haida Gwaii on October 28, in 2012. The quake prompted a regional tsunami warning to British Columbia and Alaska, but it was later cancelled. Due to the remote location of the quake, there were no reports of casualties or damage.
The 1993 Kushiro–Oki earthquake was one of two large earthquake to strike the Japanese island of Hōkkaido within the same year. The earthquake with a magnitude of 7.6 Mw or 7.8 MJMA struck at 11:06 UTC or 08:06 pm JST on January 15 near the town of Ashoro. Shaking reached a maximum intensity of IX (Violent) on the Mercalli intensity scale, causing considerable damage, and was felt throughout the island, into northern Honshu, Sakhalin, and the Kuril Islands. As a result of the tremors, two people were killed and more than 600 were wounded.
The 1906 Manasi earthquake (玛纳斯地震), also known as the Manas earthquake occurred in the morning of December 23, 1906, at 02:21 UTC+8:00 local time or December 22, 18:21 UTC. It measured 8.0–8.3 on the moment magnitude scale and 8.3 on the surface-wave magnitude scale. The epicenter of this earthquake is located in Manas County, Xinjiang, China. An estimated 280–300 people died and another 1,000 more were injured by the earthquake.
The Nemuro-Oki earthquake in scientific literature, occurred on June 17 at 12:55 local time. It struck with an epicenter just off the Nemuro Peninsula in northern Hokkaidō, Japan. It measured 7.8–7.9 on the moment magnitude scale (Mw ), 8.1 on the tsunami magnitude scale (Mt ) and 7.4 on the Japan Meteorological Agency magnitude scale (MJMA ).
On April 13, 1923 at 15:31 UTC, an earthquake occurred off the northern coast of the Kamchatka Peninsula in the USSR, present-day Russia. The earthquake had a surface-wave magnitude (Ms ) of 6.8–7.3 and an estimated moment magnitude (Mw ) of 7.0–8.2. This event came just two months after a slightly larger earthquake with an epicenter struck south of the April event. Both earthquakes were tsunamigenic although the latter generated wave heights far exceeding that of the one in February. After two foreshocks of "moderate force", the main event caused considerable damage. Most of the 36 casualties were the result of the tsunami inundation rather than the earthquake.
The 1889 Chilik earthquake occurred on July 11 on the Gregorian calendar, or June 30 on the Julian calendar at 15:14 local time in the Tien Shan mountains. The earthquake measured an estimated Mw 7.9–8.0 on the moment magnitude scale and was assigned a maximum intensity of X (Devastating) on the MSK 64 and Rossi-Forel scales. Over 92 people across Kazakhstan, Kyrgyzstan and China were killed.
The 1979 Petatlán earthquake, also known as the IBERO earthquake occurred on March 14 at 05:07 local time in the Mexican state of Guerrero. The earthquake had a surface wave magnitude of Ms 7.6 or moment magnitude of Mw 7.4 and maximum Modified Mercalli intensity of VIII (Severe). The epicenter, onshore, was located 12 km south southeast of Vallecitos de Zaragoza.
The 1933 Sumatra earthquake or Liwa earthquake occurred in West Lampung Regency, Lampung Province, Indonesia on June 25. The earthquake had an estimated surface-wave magnitude (Ms ) of 7.7 occurring at a shallow depth of 20 km. It had an epicenter onshore, devastating the city of Liwa. At least 76 people were reported killed, although the death toll may have been in the thousands. Aftershocks followed, including one which was strong enough to cause additional fatalities. The mainshock also triggered a nearby volcanic eruption two weeks later, killing some people.
On 22 January 1988, a sequence of destructive earthquakes measuring 6.2, 6.3, and 6.6 struck southwest of Tennant Creek, Australia which was felt as far north as Darwin and in other regions of the country. The largest event of the sequence was the largest earthquake ever recorded in mainland Australia since records began in 1800. An intensity of IX (Violent) was observed. Despite the large magnitude of the earthquakes and a close proximity to a town, in a country where earthquakes of this size are not common, damages were limited. Thousands of aftershocks were reported and felt across Northern Territory.
