The 1989 Malawi earthquake occurred on 10 March in central

Malawi Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeas ...

, with a

moment magnitude The moment magnitude scale (MMS; denoted explicitly with or Mw, 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. It was defined in a 1979 pape ...

of 6.3 and a maximum

Mercalli intensity The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

of VIII (''Severe''). It was preceded by a number of

foreshock A foreshock is an earthquake that occurs before a larger seismic event (the mainshock) and is related to it in both time and space. The designation of an earthquake as ''foreshock'', ''mainshock'' or aftershock is only possible after the full se ...

s, the largest being a 5.7 shock on the previous day. The earthquake was felt strongly throughout central Malawi, and also felt in parts of

Mozambique Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi ...

(

Niassa Niassa is a province of Mozambique. It has an area of 129,056 km2 and a population of 1,810,794 (2017). It is the most sparsely populated province in the country. Lichinga is the capital of the province. There are a minimum estimated 450,000 Ya ...

and

Tete Province Tete is a province of Mozambique. It has an area of 98,417 km² and a population of 2,648,941 (2017 census). Tete is the capital of the province. The Cahora Bassa Dam is situated in this province. Districts On March 21, 2013, Mozambi ...

s) and

Zambia Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most central point. Its neighbours are t ...

( Eastern Province). Nine people were killed, with many others injured or left homeless.

Geology

The 1989 Malawi earthquake was the result of a

dip-slip 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 tecton ...

in the Malawi rift system, part of the larger East African Rift. It is believed to have occurred at a depth of about , with the lack of

surface faulting In seismology, surface rupture (or ground rupture, or ground displacement) is the visible offset of the ground surface when an earthquake rupture along a fault affects the Earth's surface. Surface rupture is opposed by buried rupture, where the ...

being attributed to its occurrence at a relatively deep level. 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 ...

(ISC) placed the

epicentre 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. Surface damage Before the instrumental pe ...

of the 1989 Malawi earthquake at , although the accuracy of their determination was affected by the lack of

seismic station A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, Types of volcanic eruptions, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to f ...

s in the area – the closest was away, and there were only two within . It has been suggested that the

margin of error The margin of error is a statistic expressing the amount of random sampling error in the results of a survey. The larger the margin of error, the less confidence one should have that a poll result would reflect the result of a census of the e ...

for the epicentre is consequently around . The earthquake triggered landslides in the Manyani Hills, around east northeast of

Kasungu Kasungu is a town in the Kasungu District of the Central Region of Malawi. The population of Kasungu was 58,653 according to the 2018 census. Kasungu is approximately north-west of the capital of Malawi, Lilongwe, and is east of Kasungu N ...

Slumping Slumping is a technique in which items are made in a kiln by means of shaping glass over molds at high temperatures. The slumping of a pyrometric cone is often used to measure temperature in a kiln. Technique Slumping glass is a highly techni ...

of in length and in width was observed, and attributed to heavy rainfall earlier in the year combined with

deforestation Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated ...

-related soil exposure. There was also a large rock fall in the Chongomi Mountains of

Dedza District Dedza is a district in the Central Region of Malawi. It covers an area of 3,624 km.² to the south of the Malawi capital, Lilongwe, between Mozambique and Lake Malawi. The capital is Dedza. Geography The western part of the district is on t ...

, which resulted in hillside scarring. However, both of those areas were sparsely populated, and there were no reported casualties.

Damage and casualties

Nine people are known to have been killed as a result of the earthquake – six in

Dedza Dedza is the main township of Dedza District in the Central Region of Malawi. Description Dedza is located about 85 km south of Malawi's capital, Lilongwe, off the M1 road to Blantyre at a point where a trans-African highway from Johann ...

, two in Salima, and one in

Chitala ''Chitala'' is a genus of fish of the family Notopteridae. This genus contains six species, in which some are important in aquaculture and the aquarium industry. They are commonly known as the Asian knifefishes or featherbacks. They are native ...

. At least two of the deaths (one in Dedza and one in Chitala) were caused by roof collapses, in both cases occurring in houses with roofs built from blocks of baked clay (a non-standard method of construction). The total number of injuries from the earthquake has been estimated at 100, and the total number of people left homeless at about 50,000. Urban areas were worst affected by the quake, as houses were more likely to be built of brick and thus more susceptible to cracking. The major building with the most visible damage was the Nanjoka Railway Station complex, which developed severe cracks in its walls and was subsequently abandoned. The Chitala Farm Institute, an

agricultural school Agricultural education is the teaching of agriculture, natural resources, and land management. At higher levels, agricultural education is primarily undertaken to prepare students for employment in the agricultural sector. Classes taught in an ...

, was also heavily damaged. In rural areas, most dwellings were simple huts, built by pasting mud or clay onto timber frames. These were left mostly undamaged.

Aftermath

In the same month as the earthquake, Malawi was hit by a cyclone and suffered severe flooding. The combination of natural disasters left over 200,000 people homeless and led to the government appealing for international assistance. A field study conducted in October 1989 concluded that the March 1989 earthquake "should be treated as an eye opener, drawing attention to the potential of medium-size earthquakes hitting major cities in Malawi".

References

External links

M 6.2 - Malawi
–

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

* {{DEFAULTSORT:1989 Malawi earthquake Earthquakes in Malawi Malawi earthquake, 1989 Malawi earthquake, 1989 March 1989 events in Africa