The 1954 Chlef earthquake struck El Asnam Province in

French Algeria French Algeria ( until 1839, then afterwards; unofficially ; ), also known as Colonial Algeria, was the period of History of Algeria, Algerian history when the country was a colony and later an integral part of France. French rule lasted until ...

on 9 September at . The shock measured 6.7 on the

moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mwg, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. was defined in a 1979 paper ...

and had a maximum Mercalli intensity of XI (''Extreme''). It destroyed

Chlef Chlef () is the capital of Chlef Province, Algeria. Located in the north of Algeria, west of the capital, Algiers, it was founded in 1843, as Orléansville, on the ruins of Roman ''Castellum Tingitanum''. In 1962, it was renamed al-Asnam, but ...

, then named Orléansville, leaving over 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.

Geology

Powerful earthquakes strike Algeria annually, ranging in

Mercalli intensity scale The Modified Mercalli intensity scale (MM, MMI, or MCS) measures the effects of an earthquake at a given location. This is in contrast with the seismic magnitude usually reported for an earthquake. Magnitude scales measure the inherent force or ...

intensity from VI (''Strong'') to XI (''Extreme''). Chlef was hit by another major earthquake in 1980 which killed 3,500 people. The

Atlas Mountains The Atlas Mountains are a mountain range in the Maghreb in North Africa. They separate the Sahara Desert from the Mediterranean Sea and the Atlantic Ocean; the name "Atlantic" is derived from the mountain range, which stretches around through M ...

area faces aseismic deformation (change in shape not originating from movement of faults), with only marginal plate shifting each year. Both Chlef earthquakes originated from the same

reverse fault In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic f ...

zone. The 1954 earthquake measured 6.7 on the

according to the

International Seismological Centre The International Seismological Centre (ISC) is a non-governmental, nonprofit organisation charged with the final collection, definitive analysis and publication of global seismicity. The ISC was formed in 1964 as an international organisation ...

and had a depth of . There is evidence of

crustal shortening Thrust tectonics or contractional tectonics is concerned with the structures formed by, and the tectonic processes associated with, the shortening and thickening of the crust or lithosphere. It is one of the three main types of tectonic regime, t ...

along a NW-SE trend near the epicenter, but the structure of any faults is poorly understood.El-Robrini, Gennesseaux, and Mauffret, pg 171. Because Algeria has a thin shelf and a steep coastal slope, submarine

landslide Landslides, also known as landslips, rockslips or rockslides, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, mudflows, shallow or deep-seated slope failures and debris flows. Landslides ...

s are quite common, especially during earthquakes.El-Robrini, Gennesseaux, and Mauffret, pgs 171–2. During the 1954 earthquake, five underwater telephone cables in the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

were cut by an avalanche, three recording the exact time of impact.

Damage and casualties

Shaking extended west to

Mostaganem Mostaganem () is a port city in and capital of Mostaganem (province), Mostaganem province, in the northwest of Algeria. The city, founded in the 11th century lies on the Gulf of Arzew, Mediterranean Sea and is 72 km ENE of Oran. It is consi ...

, south to

Tiaret Tiaret () or Tahert () is a major city in northwestern Algeria that gives its name to the wider farming region of Tiaret Province. Both the town and region lie south-west of the capital of Algiers in the western region of the Hautes Plaines, i ...

, and east to

Tizi Ouzou Tizi Ouzou or Thizi Wezzu (, Kabyle: Tizi Wezzu) is a city in north central Algeria, and capital of Tizi Ouzou Province and Tizi Ouzou District. It is among the largest cities in Algeria. It is the second most populous city in the Kabylia reg ...

, and many

aftershock In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in Epicenter, the same area of the Mainshock, main shock, caused as the displaced Crust (geology), crust adjusts to the effects of the main shock. Large earthq ...

s followed the earthquake, including a major tremor at 22:18

UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communica ...

on 16 September which further damaged Orleansville. The main shock ruptured of rock, ripping faults and creating visible fissures in the ground along the Dahra

Massif A massif () is a principal mountain mass, such as a compact portion of a mountain range, containing one or more summits (e.g. France's Massif Central). In mountaineering literature, ''massif'' is frequently used to denote the main mass of an ...

. Survivors described a sensation of rotating along an axis and that the rubble reminded them of "bombed cities in Europe." The

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...

lists the 1954 quake among the deadliest earthquakes in history.

Agence France-Presse Agence France-Presse (; AFP) is a French international news agency headquartered in Paris, France. Founded in 1835 as Havas, it is the world's oldest news agency. With 2,400 employees of 100 nationalities, AFP has an editorial presence in 260 c ...

(AFP) reported that it was the worst earthquake in North African history.

Aftermath

The

French Army The French Army, officially known as the Land Army (, , ), is the principal Army, land warfare force of France, and the largest component of the French Armed Forces; it is responsible to the Government of France, alongside the French Navy, Fren ...

on the spot largely participated in the relief and triggered the first airlift

aeromedical evacuation Aeromedical evacuation (AE) is the use of military transport aircraft to carry wounded personnel. The first recorded British ambulance flight took place in 1917 in the Sinai Peninsula some 30 miles south of El Arish when a Royal Aircraft ...

in Africa.

Bell 47 The Bell 47 is a single-rotor single-engine light helicopter manufactured by Bell Helicopter. It was based on the third Bell 30 prototype, which was the company's first helicopter designed by Arthur M. Young. The 47 became the first heli ...

G helicopters, three

Amiot AAC.1 The Junkers Ju 52/3m (nicknamed ''Tante Ju'' ("Aunt Ju") and ''Iron Annie'') is a transport aircraft that was designed and manufactured by German aviation company Junkers. First introduced during 1930 as a civilian airliner, it was adapted int ...

Toucan and two

Douglas DC-3 The Douglas DC-3 is a propeller-driven airliner manufactured by the Douglas Aircraft Company, which had a lasting effect on the airline industry in the 1930s to 1940s and World War II. It was developed as a larger, improved 14-bed sleeper ...

evacuated 396 victims, including 147 on the first day, avoiding any traffic jams on site.Ollivier et Monjauze, « Le service de santé de l’Air en Algérie », Regards sur la France, no 7 « Le service de santé des armées en Algérie 1830-1958, numéro spécial », octobre-novembre 1958, p. 257-264.

Orléansville Chlef () is the capital of Chlef Province, Algeria. Located in the north of Algeria, west of the capital, Algiers, it was founded in 1843, as Orléansville, on the ruins of Roman ''Castellum Tingitanum''. In 1962, it was renamed al-Asnam, but aft ...

was devastated by the earthquake; a fifth of it wholly destroyed, it was rebuilt and renamed El Asnam and later Chlef. While Algeria had set earthquake resistance regulations as early as 1717, it was the 1954 earthquake that ushered in fully comprehensive reforms for seismic-resistant design.

References

Sources

External links

* {{Earthquakes in the 1950s 1954 disasters in Algeria 1954 earthquakes September 1954 in Africa

1954 Events January * January 3 – The Italian broadcaster RAI officially begins transmitting. * January 7 – Georgetown–IBM experiment: The first public demonstration of a machine translation system is held in New York, at the head ...