The 1804 Almería earthquake was a highly destructive

seismic event An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they c ...

in the

Province of Almería Almería (, also ; ) is a province of the autonomous community of Andalusia, Spain. It was named after the Arab ruler of Taifa, Banu Al-Miri. It is bordered by the provinces of Granada, Murcia, and the Mediterranean Sea. Its capital is the homony ...

, southern Spain. It occurred on 25 August at 8:25 pm

local time Local time is the time observed in a specific locality. There is no canonical definition. Originally it was mean solar time, but since the introduction of time zones it is generally the time as determined by the time zone in effect, with daylight s ...

. The mainshock had a maximum intensity assigned VIII–IX on the

European macroseismic scale The European Macroseismic Scale (EMS) is the basis for evaluation of seismic intensity in European countries and is also used in a number of countries outside Europe. Issued in 1998 as an update of the test version from 1992, the scale is referred ...

(EMS), and an estimated

moment magnitude 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 ...

of 6.2–6.4 . At least 400 people were reported killed.

Tectonic setting

Southern Spain is located within a zone of compression caused by the complex

convergence Convergence may refer to: Arts and media Literature *''Convergence'' (book series), edited by Ruth Nanda Anshen *Convergence (comics), "Convergence" (comics), two separate story lines published by DC Comics: **A four-part crossover storyline that ...

between the Nubian and Iberian plates. The plate boundary location remains poorly defined. Seismicity is high in a zone known as the Eastern Betics Shear Zone. Moderately large earthquakes greater than magnitude 4.5 are infrequent, but have been destructive. Almería experienced heavy damage during the earthquakes of 1487, 1522, 1658, 1804 and 1910. The earthquakes associated with these faults display reverse and left-lateral slip.

Earthquake

Earthquakes in the Almería region are associated with shallow faulting on northwest–southeast and north–south trending faults. Prior to the mainshock in August, a strong earthquake was also reported in the region on 13 January 1804. It had an approximate epicenter south–southwest of

Motril Motril () is a town and municipality of Spain belonging to the province of Granada, in the autonomous community of Andalusia. The main settlement is located a few kilometers inland, separated from the Port of Motril by the Guadalfeo delta. Mo ...

. The town sustained damage that corresponded to VII–VIII on the EMS scale. It had a moment magnitude estimated to be 6.3. Based on the macroseismic data available, the approximate epicenter would likely be in the Alboran Sea or near the heavily damaged town of Dalías. The offshore epicenter location was given as 36.6°N, 2.8°W, while the onshore location was 36.80°N, 2.85°W, with moment magnitudes of 6.2 and 6.4, respectively.

Damage

The town of

Dalías Dalías is a Municipalities of Spain, municipality of Almería (province), Almería province, in the autonomous community of Andalusia, Spain. Demographics See also *List of municipalities in Almería References

Municipalities in t ...

experienced the greatest damage and loss. All the buildings in the town were destroyed, and 267 people were killed. Damage corresponded to VIII–IX on the EMS scale. Within 45 minutes of the mainshock, three strong aftershocks and many weaker ones were felt. Five shocks were felt at

Albuñol Albuñol is a town in the province of Granada, Spain. Located a few miles inland, it is regarded as one of the gateways to the Alpujarras mountains. The municipality includes the small beach resort of La Rabita. Demography According to the 20 ...

. Homes were damaged in Rochetta. A total of 2,500 homes were heavily damaged or destroyed and over 4,000 were slightly damaged. In Berja, homes collapsed, while the walls and towers of churches toppled. An estimated 36–45 people died in the town. Many were killed while fleeing from buildings. In the flat plains, heavy damage was reported, many buildings were left in a state of ramshackle. The Temple of the Annunciation, a parish in the city, as well as several buildings were in shambles. The city of

Almería Almería (, , ) is a city and municipalities in Spain, municipality of Spain, located in Andalusia. It is the capital of the province of Almería, province of the same name. It lies in southeastern Iberian Peninsula, Iberia on the Mediterranean S ...

was subjected to VII intensity shaking, causing buildings to crack. Many residents became fearful, and the local government had to impose new regulations to maintain orderly conduct.

Saint Stephen's Day Saint Stephen's Day, also called the Feast of Saint Stephen, is a Christian saint's day to commemorate Saint Stephen, the first Christian martyr or protomartyr, celebrated on 26 December in Western Christianity and 27 December in Eastern Ch ...

festivities were prohibited due to debris on the streets. Four deaths and many injuries were recorded in

Canjáyar Canjáyar is an agricultural town in Almería province, in the autonomous community of Andalusia, Spain. It is situated along the river Andarax in the Alpujarra region of Almería 47 kilometers from the provincial capital, Almería. The mild clim ...

. A total of 60 homes were destroyed. In the aftermath, 120 additional homes and a church were to be demolished. Collapses also occurred in

Roquetas de Mar Roquetas de Mar () is a municipality of Almería province, in the autonomous community of Andalucía, Spain. In 2016, the population was 91,965, the municipality with the second highest population in the province behind the capital, the 14th i ...

, where the seismic intensity was evaluated to be VIII. The town hall and church sustained cracks on its floors. The church of Adra was damaged but remained open. The two upper sections of the church were demolished and reconstructed. Significant damage was observed in the

Alpujarras The Alpujarra (, ) is a natural and historical region in Andalusia, Spain, on the south slopes of the Sierra Nevada and the adjacent valley. The average elevation is above sea level. It extends over two provinces, Granada and Almería; ...

. At

Turón Turón is a municipality in the province of Granada, Spain. As of 2010, it has a population of 297 inhabitants. See also * List of municipalities in Granada Province of Granada, Granada is a provinces of Spain, province in the Autonomous co ...

, homes had to be demolished. Many structures in

were affected, including the towers of a church.

Fissure A fissure is a long, narrow crack opening along the surface of Earth. The term is derived from the Latin word , which means 'cleft' or 'crack'. Fissures emerge in Earth's crust, on ice sheets and glaciers, and on volcanoes. Ground fissure A ...

s and

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 occurred on the nearby mountainsides. However, there were only two injuries. One home was destroyed in Ohanes. Landslides caused additional damage to buildings. According to government information, the official death toll was 173, but a work published by Instituto Geográfico Nacional suggested the actual death toll exceeded 200. A total death toll of 400 was totaled in the towns of

Berja Berja () is a municipality, former bishopric and Latin titular see in Almería (province), Almería province, in the autonomous community of Andalusia, southern Spain. It is located on the south-eastern slope of the Sierra de Gádor, 16 km ...

and Dalías. The

Gaceta de Madrid La Gaceta may refer to * ''La Gaceta'' (Honduras), the official journal of the Republic of Honduras. * ''La Gaceta'' (Tampa), a trilingual newspaper in Tampa, Florida, United States * ''La Gaceta'' (Tucumán), a newspaper in San Miguel de Tucum� ...

cited a death toll of 407. The heavy losses resulted in the government granting tax exemptions to the populations of Almería, Berja, Dalias, Vícar, Roquetas, Canjáyar, Adra, Ugíjar, Motril and Turón.

References

{{earthquakes in Spain 1800s disasters in Europe Earthquakes in Spain 1804 in Spain Geography of the Province of Almería History of Andalusia 1804 earthquakes