UTC time | 1982-12-13 09:12:51 |
---|---|
ISC event | 586778 |
USGS-ANSS | ComCat |
Local date | December 13, 1982 |
Local time | 12:12:51 SAST |
Magnitude | 6.2 Mw [1] [2] |
Depth | 10 km (6.2 mi) [1] [2] |
Epicenter | 14°38′N44°18′E / 14.64°N 44.3°E [1] |
Type | Dip-slip (normal) |
Areas affected | Yemen |
Max. intensity | MMI VIII (Severe) [3] |
Casualties | 2,800 dead [3] 1,500 injured [4] |
The 1982 North Yemen earthquake hit near the city of Dhamar, North Yemen (now part of Yemen) on December 13. Measuring 6.2 on the moment magnitude scale, with a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale, as many as 2,800 people were killed and another 1,500 injured. The shock occurred within several hundred kilometers of a plate boundary in a geologically complex region that includes active volcanoes and seafloor spreading ridges. Yemen has a history of destructive earthquakes, though this was the first instrumentally recorded event to be detected on global seismograph networks.
The southwestern portion of the Arabian plate lies adjacent to the Afar Triple Junction (an area of spreading ridges) near the Red Sea. The triple junction marks the intersecting point of the Arabian, African, and Somali plates. Spreading initiated around 5 mya and persists at 6–7.5 mm per year in the southern Red Sea and ~10 mm per year in the eastern Gulf of Aden. Earthquake activity is normally focused at the undersea ridges, but infrequent small to moderate events occur on land in the interior of the Arabian plate within 200–300 km (120–190 mi) of the centerline of the Red Sea in Yemen, as well as farther to the northwest in the 'Asir Region of Saudi Arabia. [5]
There were 30 specific years where individual or multiple earthquakes were documented in Yemen for the 1,240 years prior to 1982. During the 20 century, in 1909, a shock resulted in the deaths of 300 people and damaged 400 homes; in 1941, two shocks, Ms 5.8 and 6.2, killed 1,200 and destroyed 1,400 homes. Other, minor, events occurred in 1955 and again in 1959. [3]
The event was a first in several classifications. It was the first instrumentally located earthquake in the southern Arabian Peninsula since 1959 and the first shock that resulted in fatalities since 1941. The earthquake was also the first in the area to be detected teleseismically on the Worldwide Standard Seismograph Network and the Global Digital Seismograph Network. [6]
Because the shock occurred 200 kilometers (120 mi) from the Red Sea Rift, it was described by Langer et al. as a "plate marginal", rather than an intraplate event. Analysis of the source parameters revealed that the main shock was a complex normal faulting event, and consisted of two equal sized shocks, separated by about 12 seconds. It was compared to the 1983 Coalinga and 1984 Morgan Hill earthquakes, both of which were events in California which had similar dual shock characteristics. [6]
An east-west trending zone 45 km (28 mi) long and 35 km (22 mi) across was assigned VIII (Severe) on the Mercalli intensity scale. This zone covered a 1,400 km2 (540 sq mi) area. There, masonry stone and mud brick dwellings partially or totally collapsed, accounting for the majority of deaths. Single floor concrete masonry buildings were cracked but structurally resilient. Damage was greater to buildings situated on bedrock rather than young sedimentary layers. While there were no major landslides, individual rocks as large as 0.6 m (2 ft 0 in) across toppled in areas with steep terrain. Intensity VII (Very strong) enveloped the meizoseismal area, extending 75 km (47 mi) and 65 km (40 mi) in the east–west and north–south directions, respectively. [7]
The shallow mainshock occurred in a highly populated area 70 kilometers (43 mi) south of Sana'a. The primary event and its aftershocks created a zone of destruction between Ma'bar and Dhamar, where older villages were heavily damaged, with adobe or rubble masonry homes suffering the most. Homes and villages that were adjacent to steep slopes or cliffs were susceptible to rockfalls and landslides, but damage was much less pronounced away from the epicentral area, and modern city centers with properly engineered structures were only slightly affected. [8]
The National Earthquake Information Center reported that 2,800 people died and that another 1,500 were injured. [4] Other estimates for the total deaths range from 1,600 to 3,000. [5] [9] About 63 mi (101 km) from Sanaa, the village of Dhuran Anis lost at least 335 residents. The state information minister also said 150 schoolchildren died when their school was levelled, [10] and a collapsing mosque killed 40 attendees. [11] In all, nearly 300 villages were severely damaged or destroyed and about 700,000 were made homeless. [4] The earthquake was felt in North Yemen and much of South Yemen as well as into Saudi Arabia. [3]
Beginning sixteen days after the mainshock a portable seismograph network consisting of mostly analog units was deployed in the epicentral area. Six days of recording, capturing thousands of aftershocks, were obtained under its final and optimum configuration. Two of the larger events, the December 29 M5.3 event and the January 8 M4.6 event, were also recorded teleseismically during this period. [12]
The initial search and rescue efforts were hampered by communication problems and road conditions. Chaos and looting also ensued in some of the devastated places. Relief teams from Saudi Arabia and Palestinians who fled Lebanon following the Israeli invasion also assisted local rescuers. [10]
Several Arab states immediately attended to the disaster by deploying relief teams and supplies. Saudi's defence minister, Sultan bin Abdulaziz, said 36 aircraft flew to Yemen, carrying aid such as medicine and a field hospital. [10] Other nearby states also provided medical personnel, blood and equipment. [13] Other nations including Kuwait, Qatar, the United Arab Emirates, West Germany, Switzerland, and the Netherlands also offered aid. The Saudi Arabia-backed International Red Cross contributed significantly to the international response. [14]
The 1886 Charleston earthquake in South Carolina occurred about 9:50 p.m. local time August 31. It caused 60 deaths and $5–6 million in damage to 2,000 buildings in the Southeastern United States. It is one of the most powerful and damaging earthquakes to hit the East Coast of the United States.
The 1993 Scotts Mills earthquake, also known as the "Spring break quake", occurred in the U.S. state of Oregon on March 25 at 5:34 AM Pacific Standard Time. With a moment magnitude of 5.6 and a maximum perceived intensity of VII on the Mercalli intensity scale, it was the largest earthquake in the Pacific Northwest since the Elk Lake and Goat Rocks earthquakes of 1981. Ground motion was widely felt in Oregon's Willamette Valley, the Portland metropolitan area, and as far north as the Puget Sound area near Seattle, Washington.
The 1976 Guatemala earthquake struck on February 4 at 03:01:43 local time with a moment magnitude of 7.5. The shock was centered on the Motagua Fault, about 160 km northeast of Guatemala City at a depth of 5 kilometers (3.1 mi) near the town of Los Amates in the department of Izabal.
The 2008 Illinois earthquake was one of the largest earthquakes ever recorded in the Midwest state of Illinois. This moderate strike-slip shock measured 5.2 on the moment magnitude scale and had a maximum Mercalli intensity of VII (Very strong). It occurred at 04:36:59 local time on April 18 near Bellmont and Mount Carmel, Illinois, within the Wabash Valley Seismic Zone. Earthquakes in this part of the country are often felt at great distances.
The 1992 Big Bear earthquake occurred at 08:05:33 PDT on June 28 in Big Bear Lake, California, with a moment magnitude of 6.5 and a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale. The earthquake occurred at a relatively shallow depth of 5 kilometers (3.1 mi).
The Dasht-e Bayaz and Ferdows earthquakes occurred in Dashte Bayaz, Kakhk and Ferdows, Iran in late August and early September 1968. The mainshock measured 7.1 on the moment magnitude scale and had a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. Damage was heavy in the affected areas with thousands of lives lost in the first event and many hundreds more in the second strong event.
In the early morning hours of August 16, 1931, a powerful earthquake occurred in West Texas with a maximum Mercalli intensity of VIII (Severe). Estimates of its magnitude range between 5.8 and 6.4 mb, making it the most powerful earthquake ever recorded in Texas history. Its epicenter was near the town of Valentine, Texas; there, the earthquake caused damage to many homes and buildings. The earthquake may have been caused by movement along oblique-slip faulting in West Texas, the most seismically active region in the state. Shaking from the earthquake was perceptible within a 400 mi (640 km) radius of the epicenter, affecting four U.S. states and northern Mexico. Several foreshocks and aftershocks accompanied the primary temblor, with the aftershocks continuing until at least November 3, 1931. The main earthquake caused no fatalities, though several people sustained minor injuries; the damage in Valentine amounted to $50,000–$75,000.
The 1986 Chalfant Valley earthquake struck southern Mono County near Bishop and Chalfant, California at 07:42:28 Pacific Daylight Time on July 21. With a moment magnitude of 6.2 and a maximum Mercalli intensity of VI (Strong), the shock injured two people and caused property damage estimated at $2.7 million in the affected areas. There was a significant foreshock and aftershock sequence that included a few moderate events, and was the last in a series of three earthquakes that affected southern California and the northern Owens Valley in July 1986.
The 1995 Colima–Jalisco earthquake occurred on October 9 at 15:35 UTC with a moment magnitude of 8.0 and a maximum Mercalli intensity of VIII (Severe). The shock occurred off the coast of Jalisco, Mexico, where a tsunami was triggered that affected a 200 km (120 mi) stretch of the coast. The earthquake could be felt in Mexico City and in high-rise buildings in Dallas and Houston. In Mexico, the Cihuatlan-Manzanillo was the most severely affected area. At least 49 people died and 100 were injured.
The 1940 El Centro earthquake occurred at 21:35 Pacific Standard Time on May 18 in the Imperial Valley in southeastern Southern California near the international border of the United States and Mexico. It had a moment magnitude of 6.9 and a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. It was the first major earthquake to be recorded by a strong-motion seismograph located next to a fault rupture. The earthquake was characterized as a typical moderate-sized destructive event with a complex energy release signature. It was the strongest recorded earthquake in the Imperial Valley, causing widespread damage to irrigation systems and killing nine people.
The 1995 Gulf of Aqaba earthquake occurred on November 22 at 06:15 local time and registered 7.3 on the Mw scale. The epicenter was located in the central segment of the Gulf of Aqaba, the narrow body of water that separates Egypt's Sinai Peninsula from the western border of Saudi Arabia. At least 8 people were killed and 30 were injured in the meizoseismal area.
The 1930 Irpinia earthquake occurred at 00:08 UTC on 23 July, chiefly in an area known as Irpinia. It had a surface-wave magnitude of 6.6 and a maximum intensity of X . The event caused 1,404 deaths and 4,624–7,000 injuries. The epicenter was near the boundaries between the regions of Basilicata, Apulia, and Campania.
The 1872 North Cascades earthquake occurred at 9:40 p.m. local time on December 14 in central Washington Territory. A maximum Mercalli intensity of VIII (Severe) was assessed for several locations, though less intense shaking was observed at many other locations in Washington, Oregon, and British Columbia. Some of these intermediate outlying areas reported V (Moderate) to VII shaking, but intensities as high as IV (Light) were reported as far distant as Idaho and Montana. Due to the remote location of the mainshock and a series of strong aftershocks, damage to structures was limited to a few cabins close to the areas of the highest intensity.
The 1969 Sharm El Sheikh earthquake occurred on March 31 off the southern Sinai Peninsula in northeastern Egypt. The epicenter was located near Shadwan island, southwest of the city of Sharm El Sheikh, at the confluence of the Red Sea and the Gulf of Suez. This normal-slip shock measured 6.6 on the moment magnitude scale, had a maximum reported intensity of VII on the Mercalli intensity scale, and was responsible for several deaths and injuries.
The 1979 Coyote Lake earthquake occurred at 10:05:24 local time on August 6 with a moment magnitude of 5.7 and a maximum Mercalli Intensity of VII. The shock occurred on the Calaveras Fault near Coyote Lake in Santa Clara County, California and resulted in a number of injuries, including some that required hospitalization. Most of the $500,000 in damage that was caused was non-structural, but several businesses were closed for repairs. Data from numerous strong motion instruments was used to determine the type, depth, and extent of slip. A non-destructive aftershock sequence that lasted throughout the remainder of the month was of interest to seismologists, especially with regard to fault creep, and following the event local governments evaluated their response to the incident.
The 1980 Eureka earthquake occurred on November 8 at 02:27:34 local time along the northern coastal area of California in the United States. With a moment magnitude of 7.3 and a maximum Mercalli intensity of VII, this strike-slip earthquake was the largest to occur in California in 28 years. Although damage was considered light, several loss estimates equaled or exceeded $2 million, and six injuries resulted when two vehicles came down with the partial collapse of a highway overpass on US 101 in Fields Landing. The north coast of California experiences frequent plate boundary earthquakes near the Mendocino Triple Junction and intraplate events also occur within the Gorda plate.
The 1981 Sirch earthquake occurred at 00:22 local time on July 28. It had a magnitude of 7.1 on the surface-wave magnitude scale and a maximum perceived intensity of IX (Violent) on the Mercalli intensity scale. The epicentre was in the province of Kerman in eastern Iran. The earthquake caused the destruction of Kerman and serious damage to towns and villages in the surrounding area. The estimated number of deaths is 1,500, with a further 1,000 injured, 50,000 homeless, and extensive damage in the Kerman Region.
On December 22, 1983, an earthquake with a magnitude of 6.3 struck northern Guinea, killing around 300 people, and injuring 1,500. Around 200 people went missing. An earthquake of this magnitude was unusual for this region of West Africa, which was previously believed by most seismologists to be aseismic. The earthquake destroyed 5,000 houses. It had an intensity of IX (Violent) on the Mercalli intensity scale, although USGS reported it as VIII (Severe). The earthquake caused cracks in the ground, and an entire cavern to collapse.
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 1941 Sa'dah earthquake or the Jabal Razih earthquake occurred on January 11 in Razih District of the Mutawakkilite Kingdom of Yemen. The earthquake had a surface-wave magnitude of 5.8–6.5 and a shallow focal depth. Despite the moderate size of this earthquake, an estimated 1,200 people perished and at least 200 injured. With a maximum MSK-64 intensity assigned at VIII, it destroyed many villages and collapsed homes in the region of North Yemen.
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