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. [1] [2] There are many more earthquakes and tsunamis originating from the region.
The southern part of the Kamchatka peninsula lies above the convergent plate margin where the Pacific Plate is subducting beneath the Okhotsk Plate along the line of the Kuril–Kamchatka Trench. The rate of convergence between the two plates is about 86 mm per year. [3] Earthquakes are generated by rupture along the megathrust boundary between the two plates, within the descending Pacific Plate and within the overriding Okhotsk Plate. The northern part of the peninsula lies away from the convergent boundaries of the Kuril–Kamchatka Trench and the Aleutian Trench but across the boundary between two blocks within the North American Plate, the Kolyma-Chukotka and Bering Sea microplates. This boundary accommodates both active shortening and right lateral strike-slip across a series of large SW–NE trending faults. [4]
The epicentre of the 1737 earthquake was located at 52°30′N159°30′E / 52.5°N 159.5°E . This earthquake occurred at a depth of 40 km (25 miles). A magnitude of 8.3 Ms (9.0Mw) has been estimated. [5]
An earthquake of estimated magnitude 9.0 Mw , with an epicenter just offshore, which triggered a large tsunami. [6]
On February 3, 1923, an estimated magnitude 8.3–8.5 Mw earthquake with an approximate location of 54°00′N161°00′E / 54.0°N 161.0°E triggered a 25-foot tsunami that caused considerable damage in Kamchatka, with a reported 3 deaths. [7] [8] The tsunami was still 6 meters (20 feet) high when it reached Hawaii, causing at least one fatality. [7] There was another earthquake and tsunami in April 1923, which caused locally high tsunami runup near Ust' Kamchatsk, leaving a deposit studied by Minoura and others. [9]
The main earthquake struck at 16:58 GMT (November 5, 04:58 local time) on November 4, 1952. Initially assigned a magnitude of 8.2, the quake was revised to 9.0 Mw in later years. [10] A large tsunami resulted, [11] causing destruction and loss of life around the Kamchatka peninsula and the Kuril Islands. Hawaii was also struck, with estimated damage of up to US$1 million and livestock losses, but no human casualties were recorded. Japan reported no casualties or damage. The tsunami reached as far as Alaska, Chile, and New Zealand. [7] [12]
The hypocentre was located at 52°45′N159°30′E / 52.75°N 159.5°E , at a depth of 30 km (18.6 miles). The length of the subduction zone rupture was 600 km (373 miles). Aftershocks were recorded in an area of approximately 247,000 km2 (90,367 square miles), at depths of between 40 and 60 km (25 and 37 miles). [13] [14] A recent analysis of the tsunami runup distribution based on historical and geological records give some indication as to the slip distribution of the rupture. [15]
A magnitude Mw 8.0 earthquake occurred on May 4, at a hypocentral depth of 20 km, with a maximum felt intensity of VIII MSK. [6]
The region of Koryak Autonomous Okrug was struck by an Mw 7.6 earthquake on April 20 (April 21 local time). It was followed by a large number of aftershocks, including two of Mw 6.6. [16] This was a reverse faulting event along the boundary between two microplates within the North American Plate. The event caused a 140 km long zone of surface rupture. [17]
The Mw 7.5 earthquake occurred on March 25. The earthquake was the largest to occur in Russia since the 2013 Okhotsk Sea earthquake. [18] It was initially reported as 7.8 Mw , before being downgraded to 7.5. [19]
This shock was a result of near-trench intraplate compressional faulting within the descending Pacific Plate. The epicenter was in the area of the large-slip region of the 1952 Severo-Kurilsk earthquake, which was an M 9.0 megathrust event. Large compressional activity is more common before, and long after, major compressional events along coupled zones, suggesting interplate strain accumulation. [20]
In Petropavlovsk-Kamchatsky, 285 miles (460km) away from the epicenter the intensity was felt at 5, objects were falling in buildings and people ran out into the street for safety. [21] [22]
A tsunami warning was issued immediately after the earthquake. The Pacific Tsunami Warning Centre initially said hazardous tsunami waves were possible within 1,000km of the earthquake’s epicentre. It said earthquakes of this strength in the past had caused tsunamis far from the epicentre. [23] A tsunami of about 0.5 m (1.6 ft) struck Kamchatka. [24]
Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthquakes are the planet's most powerful, with moment magnitudes (Mw) that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes.
The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1, 1946. The shock measured 8.6, Mt 9.3 or 7.4. It had a maximum Mercalli intensity of VI (Strong). It resulted in 165–173 casualties and over US $26 million in damage. The seafloor along the fault was elevated, triggering a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–138 ft (14–42 m). The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers. Despite the destruction to the Aleutian Island Unimak, the tsunami had almost an imperceptible effect on the Alaskan mainland.
The Okhotsk Plate is a minor tectonic plate covering the Kamchatka Peninsula, Magadan Oblast, and Sakhalin Island of Russia; Hokkaido, Kantō and Tōhoku regions of Japan; the Sea of Okhotsk, as well as the disputed Kuril Islands. It was formerly considered a part of the North American Plate, but recent studies indicate that it is an independent plate, bounded on the north by the North American Plate. The boundary is a left-lateral moving transform fault, the Ulakhan Fault originating from a triple junction in the Chersky Range. On the east, the plate is bounded by the Pacific Plate at the Kuril–Kamchatka Trench and the Japan Trench, on the south by the Philippine Sea Plate at the Nankai Trough, on the west by the Eurasian Plate, and on the southwest by the Amurian Plate.
The Aleutian Trench is an oceanic trench along a convergent plate boundary which runs along the southern coastline of Alaska and the Aleutian islands. The trench extends for 3,400 kilometres (2,100 mi) from a triple junction in the west with the Ulakhan Fault and the northern end of the Kuril–Kamchatka Trench, to a junction with the northern end of the Queen Charlotte Fault system in the east. It is classified as a "marginal trench" in the east as it runs along the margin of the continent. The subduction along the trench gives rise to the Aleutian Arc, a volcanic island arc, where it runs through the open sea west of the Alaska Peninsula. As a convergent plate boundary, the trench forms part of the boundary between two tectonic plates. Here, the Pacific Plate is being subducted under the North American Plate at a dip angle of nearly 45°. The rate of closure is 7.5 centimetres (3 in) per year.
The 1957 Andreanof Islands earthquake occurred at 04:22 local time on March 9 with a moment magnitude estimated between 8.6 and 9.1 and a maximum Modified Mercalli intensity of VIII (Severe). It occurred south of the Andreanof Islands group, which is part of the Aleutian Islands arc. The event occurred along the Aleutian Trench, the convergent plate boundary that separates the Pacific Plate and the North American plates near Alaska. A basin-wide tsunami followed, with effects felt in Alaska and Hawaii, and strong waves recorded across the Pacific rim. Total losses were around $5 million.
The 2006 Kamchatka earthquake occurred on April 21, 2006 at 12:25 PM local time. This shock had a moment magnitude of 7.6 and a maximum Mercalli intensity of X (Extreme). The hypocenter was located near the coast of Koryak Autonomous Okrug at an estimated depth of 22 km, as reported by the International Seismological Centre. This event caused damage in three villages and was followed by a number of large aftershocks. Two M6.6 earthquakes struck on April 29 at 16:58 UTC and again on May 22 at 11:12 UTC. These earthquakes caused no deaths; however, 40 people were reported injured.
The 1952 Severo-Kurilsk earthquake struck off the coast of the Kamchatka Peninsula. The 9.0 Mw earthquake triggered a major tsunami that hit Severo-Kurilsk, Kuril Islands, Sakhalin Oblast, Russian SFSR, USSR, on 5 November 1952 at 04:58 local time. This led to the destruction of many settlements in Sakhalin Oblast and Kamchatka Oblast, while the main impact struck the town of Severo-Kurilsk. It was the most powerful earthquake ever recorded in Russia, and the fifth most powerful earthquake ever recorded in the world since modern seismography began in 1900.
The 1959 Kamchatka earthquake occurred on May 4 at 19:15 local time with a moment magnitude of 8.0–8.3, and a surface wave magnitude of 8.25. The epicenter was near the Kamchatka Peninsula, Russian SFSR, USSR. Building damage was reported in Petropavlovsk-Kamchatsky. The maximum intensity was VIII (Damaging) on the Medvedev–Sponheuer–Karnik scale. The intensity in Petropavlovsk-Kamchatsky was about VIII MSK.
The 1907 Sumatra earthquake occurred on January 4 at 05:19:12 UTC. The estimated magnitude is 7.5–8.0 Ms, with an epicentre close to Simeulue, off Sumatra. It triggered a widespread and damaging tsunami that caused at least 2,188 deaths. The low observed intensity compared to the size of the tsunami has led to its interpretation as a tsunami earthquake. Higher levels of shaking observed on Nias are attributed to a large aftershock, less than an hour later. The tsunami gave rise to the S'mong legend, which is credited with saving many lives during the 2004 earthquake.
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.
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.
On January 30, 1973, at 15:01 (UTC–6), a magnitude 7.6 earthquake struck 35.3 km (21.9 mi) beneath the Sierra Madre del Sur range in the Mexican states of Colima, Jalisco and Michoacán. On the Mercalli intensity scale, the earthquake reached a maximum intensity of X (Extreme), causing serious damage in the region. At least 56 people were killed and about 390 were injured. The event is commonly referred to as the Colima 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 1737 Kamchatka earthquake occurred on October 17 or 16 near the southern tip of present-day Russia's Kamchatka Peninsula. The shock was felt at approximately 03:00 local time or 16:00 UTC by residents on the peninsula and Kuril Islands. The earthquake struck at a shallow depth of roughly 40 km beneath the peninsula. The earthquake had an estimated magnitude of 9.0–9.3 on the moment magnitude scale.
The 1982 Urakawa earthquake was a Mw 6.9 earthquake that struck off the coast of Urakawa, Japan on 11:32 (JST), March 21, 1982. The epicenter was 42.1°N 142.6°E. The earthquake was the largest earthquake in the history of the region. The earthquake caused 167 injuries and damage in Tomakomai and Sapporo.
An earthquake occurred off the coast of the Alaska Peninsula on July 28, 2021, at 10:15 p.m. local time. The large megathrust earthquake had a moment magnitude of 8.2 according to the United States Geological Survey (USGS). A tsunami warning was issued by the National Oceanic and Atmospheric Administration (NOAA) but later cancelled. The mainshock was followed by a number of aftershocks, including three that were of magnitude 5.9, 6.1 and 6.9 respectively.
The 2021 South Sandwich Islands earthquakes were a pair of powerful earthquakes, followed by many strong aftershocks which struck along the South Sandwich Trench in August 2021. The quakes measured 7.5 and 8.1 on the moment magnitude scale, according to the United States Geological Survey. The mainshock is tied with another event in 1929 as the largest earthquake ever recorded in this region, and is tied with the 2021 Kermadec Islands earthquake as the second largest earthquake of 2021.
The 1841 Kamchatka earthquake occurred in the Pacific Ocean on May 17 at 08:00 local time. The earthquake had an epicenter off the Russian Far East's Kamchatka Peninsula. With an estimated moment magnitude of 9.0 or higher, it is one of the largest to strike the region. A large tsunami with up to 15 meters in run-up along the coast.
The 1958 Kuril Islands earthquake or Etorofu earthquake was a Mw 8.3–8.4 earthquake that struck near the Kuril island of Iturup on November 6, 1958, at 22:58 UTC, or 09:58 on the 7th local time. The earthquake occurred as the result of shallow reverse faulting along the Kuril-Kamchatka Trench, and caused Modified Mercalli Intensity (MMI) X (Extreme) shaking, as well as a tsunami 5 m (16 ft) high. Iturup sustained significant damage as a result of the shaking and tsunami, with other locations along the Kuril Islands also reporting strong damage.