1976 Guatemala earthquake

Last updated
1976 Guatemala earthquake
GuateQuake1976Patzicia.jpg
Relief map of Central America.jpg
Bullseye1.png
UTC  time1976-02-04 09:01:46
ISC  event 717474
USGS-ANSS ComCat
Local dateFebruary 4, 1976 (1976-02-04)
Local time03:01:43
Magnitude7.5 Mw
Depth5 kilometres (3 mi)
Epicenter 15°19′N89°06′W / 15.32°N 89.10°W / 15.32; -89.10 Coordinates: 15°19′N89°06′W / 15.32°N 89.10°W / 15.32; -89.10
Fault Motagua Fault
Type Strike-slip
Areas affected Guatemala
Max. intensity IX (Violent) [1]
Casualties23,000 fatalities, 76,000 injured

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. [1]

Contents

Cities throughout the country suffered damage, and most adobe type houses in the outlying areas of Guatemala City were destroyed. The earthquake struck during the early morning (at 3:01 am, local time) when most people were asleep. This contributed to the high death toll of 23,000. Approximately 76,000 were injured, and many thousands left homeless. Some of the areas affected went without electricity and communications for days.

The main shock was followed by thousands of aftershocks, some of the larger ones causing additional damage and loss of life. [2]

Seismic data

The quake's epicentre was located near the town of Los Amates, in the eastern part of the Motagua Fault, a left-lateral strike-slip fault that forms part of the tectonic boundary between the North American plate and the Caribbean plate. [1] Ground shaking was felt during approximately 39 seconds, and caused visible rupturing over 230 km along the Motagua fault, while the inferred length of faulting—based on aftershock registration—was estimated at 300 km. Average horizontal displacement along the Motagua fault was 100 cm, with a maximum displacement of 326 cm. [1]

Maximum seismic intensity (MM IX) was located in the Mixco area, some sections of Guatemala City and in Gualán. A seismic intensity of MM VI covered an area of 33,000 km². [1] Soil liquefaction and sand boils were observed in several locations with high seismic intensity. The main quake activated secondary fault zones, including the Mixco fault, located in a densely populated area just north-west of Guatemala City.

Victims and damage

The most heavily affected area covered some 30,000 km², with a population of 2.5 million. Some 23,000 people were reported dead and 77,000 wounded. Approximately 258,000 houses were destroyed, leaving about 1.2 million people homeless. 40% of the national hospital infrastructure was destroyed, while other health facilities also suffered substantial damage. [3]

International reaction

Immediately after the earthquake, the then president Kjell Eugenio Laugerud García invited most of the foreign ambassadors to tour the affected regions by helicopter, which prompted them to quickly ask for help in their home countries. For example, the United States of America rebuilt most of the roads, and Canada and Belgium each rebuilt a village.[ citation needed ]

Aftershocks

Several aftershocks, ranging from 5.2 to 5.8 Mw caused additional casualties and hampered relief efforts.

DateOrigin TimeCoordinatesLocationDepthMagnitude
Feb. 04 197609.30.28.3 14°42′N90°36′W / 14.7°N 90.6°W / 14.7; -90.6 7 km NNE of Mixco 5 km5.8 Mw
Feb. 06 197604.11.03.3 14°36′N91°06′W / 14.6°N 91.1°W / 14.6; -91.1 6 km SSE of San Lucas Tolimán 5 km4.8 Mw
Feb. 06 197618.11.59.2 14°18′N90°12′W / 14.3°N 90.2°W / 14.3; -90.2 11 km ENE of Cuilapa 5 km5.2 Mw
Feb. 06 197618.19.17.7 14°42′N90°36′W / 14.7°N 90.6°W / 14.7; -90.6 5 km ENE of San Pedro Sacatepéquez 5 km5.8 Mw
Feb. 08 197608.13.51.9 15°42′N88°30′W / 15.7°N 88.5°W / 15.7; -88.5 13 km SE of Puerto Barrios 5 km5.7 Mw
Feb. 09 197611.44.46.7 15°18′N89°06′W / 15.3°N 89.1°W / 15.3; -89.1 30 km WSW of Morales 5 km5.1 Mw
Feb. 10 197606.17.43.0 15°00′N89°42′W / 15.0°N 89.7°W / 15.0; -89.7 18 km WNW of Zacapa 5 km4.7 Mw
Mar. 07 197602.54.05.4 14°54′N90°54′W / 14.9°N 90.9°W / 14.9; -90.9 14.5 km SW of Joyabaj 5 km4.8 Mw
Mar. 07 197603.15.40.3 14°42′N90°30′W / 14.7°N 90.5°W / 14.7; -90.5 Chinautla (9 km North of Guatemala City)5 km4.9 Mw
Source: Wayerly Person, William Spence, and James W. Dewey. Main event and principal aftershocks from teleseismic data. In: Guatemalan Earthquake of February 4, 1976, A Preliminary Report.

See also

Notes

Related Research Articles

New Madrid Seismic Zone Major seismic zone in the southern and midwestern United States

The New Madrid Seismic Zone, sometimes called the New Madrid Fault Line, is a major seismic zone and a prolific source of intraplate earthquakes in the southern and midwestern United States, stretching to the southwest from New Madrid, Missouri.

1886 Charleston earthquake

The 1886 Charleston earthquake occurred about 9:50 p.m. local time August 31 with an estimated moment magnitude of 6.9–7.3 and a maximum Mercalli intensity of X (Extreme). The intraplate earthquake 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. Very little to no historical earthquake activity had occurred, which is unusual for any seismic area.

1993 Scotts Mills earthquake

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.

2004 Al Hoceima earthquake February 2004 earthquake in Morocco

The 2004 Al Hoceima earthquake occurred on 24 February at 02:27:47 local time near the coast of northern Morocco. The strike-slip earthquake measured 6.3 on the moment magnitude scale and had a maximum perceived intensity of IX (Violent) on the Mercalli intensity scale. Between 628 and 631 people were killed, 926 were injured, and up to 15,000 people were made homeless in the Al Hoceima-Imzourene-Beni Abdallah area.

1972 Nicaragua earthquake December 1972 earthquake in Nicaragua

The 1972 Nicaragua earthquake occurred at 12:29:44 a.m. local time on December 23 near Managua, the capital of Nicaragua. It had a moment magnitude of 6.3 and a maximum MSK intensity of IX (Destructive). The epicenter was 28 kilometers northeast of the city centre and a depth of about 10 kilometers. The earthquake caused widespread casualties among Managua's residents: 4,000–11,000 were killed, 20,000 were injured and over 300,000 were left homeless.

1983 Coalinga earthquake

The 1983 Coalinga earthquake struck at 4:42 p.m. Monday, May 2 of that year, in Coalinga, California,

1983 Borah Peak earthquake

The 1983 Borah Peak earthquake occurred on October 28, at 8:06:09 a.m. MDT in the western United States, in the Lost River Range at Borah Peak in Central Idaho.

2009 Swan Islands earthquake

The 2009 Swan Islands earthquake occurred on May 28 at 02:24:45 AM local time with a moment magnitude of 7.3 and a maximum Mercalli intensity of VII. The epicenter was located in the Caribbean Sea, 64 kilometres (40 mi) northeast of the island of Roatán, 19 miles northeast of Port Royal, Isla de Bahias, 15 miles northwest of Isla Barbaretta, and 130 kilometres (81 mi) north-northeast of La Ceiba. Three aftershocks followed the earthquake within magnitude 4 range.

1986 Chalfant Valley earthquake

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.

2011 Guerrero earthquake

The 2011 Guerrero earthquake struck with a moment magnitude of 5.7 in southern Mexico at 08:24 local time on 5 May. It was positioned west of Ometepec, Guerrero, with a focal depth of 24 km (14.9 mi), and was lightly felt in many adjacent areas.

1979 Imperial Valley earthquake

The 1979 Imperial Valley earthquake occurred at 16:16 Pacific Daylight Time on 15 October just south of the Mexico–United States border. It affected Imperial Valley in Southern California and Mexicali Valley in northern Baja California. The earthquake had a relatively shallow hypocenter and caused property damage in the United States estimated at US$30 million. The irrigation systems in the Imperial Valley were badly affected, but no deaths occurred. It was the largest earthquake to occur in the contiguous United States since the 1971 San Fernando earthquake eight years earlier.

2012 Visayas earthquake earthquake

The 2012 Visayas earthquake occurred on February 6 at 11:49 PST with a body wave magnitude of 6.7 and a maximum intensity of VII (Destructive) off the coast of Negros Oriental, Philippines. The epicenter of the submarine blind thrust earthquake was approximately 72 kilometres (45 mi) north of the provincial capital of Dumaguete City.

1935 Helena earthquake

The 1935 Helena earthquake occurred at 22:48:02 MDT on October 18 in Montana, with an epicenter near Helena. It had a magnitude of 6.2 on the surface wave magnitude scale and a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale. The temblor on that date was the largest of a series of earthquakes that also included a large aftershock on October 31 of magnitude 6.0 and a maximum intensity of VIII. Two people died in the mainshock and two others died as a result of the October 31 aftershock. Property damage was over $4 million.

1786 Kangding-Luding earthquake

An earthquake occurred on 1 June 1786 in and around Kangding, in what is now China's Sichuan province. It had an estimated magnitude of about 7.75 and a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. The initial quake killed 435 people. After an aftershock ten days later, a further 100,000 died when a landslide dam collapsed across the Dadu river.

2013 Solomon Islands earthquake

The 2013 Solomon Islands earthquake struck northeast of Australia on 6 February with a moment magnitude of 8.0 and a maximum Mercalli intensity of VIII (Severe). Its epicenter was the Solomon Islands, at the boundaries of the Australian and Pacific tectonic plates, causing local evacuations and a tsunami of 1.5 m (4.9 ft) and killing at least nine people.

1954 Chlef earthquake

The 1954 Chlef earthquake struck Chlef Province in Algeria on September 9 at 02:04:43 local time. The shock measured 6.7 on the moment magnitude scale and had a maximum Mercalli intensity of XI (Extreme). It destroyed Chlef, then named Orléansville, leaving at least 1,243 people dead and 5,000 injured. Damage was estimated at $6 million. It was followed by multiple aftershocks. Algeria faces annual earthquakes and has undergone several changes to its earthquake building codes since its first earthquake engineering regulations from 1717.

1936 State Line earthquake Earthquake affecting Oregon and Washington, USA in July 1936.

The 1936 State Line earthquake struck at 23:08 Pacific time on July 15, 1936. The earthquake had an estimated magnitude of 5.8 and a maximum Mercalli intensity of VII (Very strong). The epicenter was near the Oregon/Washington state line approximately 6 miles (9.7 km) northwest of Milton-Freewater, Oregon and southwest of Walla Walla, Washington and was felt throughout the Pacific Northwest, including as far away as Bonners Ferry, Idaho near the Canadian border and by seismographs as far away as San Diego, California.

2019 Ridgecrest earthquakes July 4–5, 2019, earthquakes in California

The 2019 Ridgecrest earthquakes of July 4 and 5 occurred north and northeast of the town of Ridgecrest, California and west of Searles Valley, California. They included three main shocks of Mw magnitudes 6.4, 5.4, and 7.1, and many perceptible aftershocks, mainly within the area of the Naval Air Weapons Station China Lake. The first main shock occurred on July 4 at 10:33 a.m. PDT, approximately 18 km (11.2 mi) ENE of Ridgecrest, and 13 km (8.1 mi) WSW of Trona, on a previously unnoticed NE-SW trending fault where it intersects the NW-SE trending Little Lake Fault Zone. This quake was preceded by several smaller earthquakes, and was followed by more than 1,400 detected aftershocks. The M 5.4 and M 7.1 quakes struck on July 5 at 4:08 a.m. and 8:19 p.m. PDT approximately 10 km (6 miles) to the northwest. The latter, now considered the mainshock, was the most powerful earthquake to occur in the state in 20 years. Subsequent aftershocks extended approximately 50 km (~30 miles) along the Little Lake Fault Zone.

References