1877 Iquique earthquake
Encyclopedia
The 1877 Iquique earthquake occurred at 21:16 local time on 9 May (0:59 on 10 May UTC
Coordinated Universal Time
Coordinated Universal Time is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose...

). It had a magnitude of 8.8 on the moment magnitude scale
Moment magnitude scale
The moment magnitude scale is used by seismologists to measure the size of earthquakes in terms of the energy released. The magnitude is based on the seismic moment of the earthquake, which is equal to the rigidity of the Earth multiplied by the average amount of slip on the fault and the size of...

 and a maximum felt intensity of XI (Extreme) on the Mercalli intensity scale
Mercalli intensity scale
The Mercalli intensity scale is a seismic scale used for measuring the intensity of an earthquake. It measures the effects of an earthquake, and is distinct from the moment magnitude M_w usually reported for an earthquake , which is a measure of the energy released...

 and triggered a devastating tsunami
Tsunami
A tsunami is a series of water waves caused by the displacement of a large volume of a body of water, typically an ocean or a large lake...

. A total of 2,541 people died, mainly in Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 and what is now northernmost Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, with some deaths also reported from Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

 and Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

.

Historical context

Affected areas in what is now the Antofagasta region of Chile had during this period been subject to the Atacama border dispute
Atacama border dispute
The Atacama border dispute was a dispute between Chile and Bolivia in the 19th century that ended in the transfer to Chile of all of the Bolivian Coast and the southern tip of Bolivia's ally Peru through the Treaty of Ancón with Peru and the Treaty of Peace and Friendship of 1904 between Chile and...

 between Bolivia and Chile. Under the 1874 boundary treaty between Bolivia and Chile, the border between Bolivia and Chile in 1877 followed the 24th parallel south
24th parallel south
The 24th parallel south is a circle of latitude that is 24 degrees south of the Earth's equatorial plane, about 60km south of the Tropic of Capricorn...

. The terms of that treaty required that Bolivia not levy
taxes on Chilean companies mining nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...

s between the 23rd
23rd parallel south
The 23rd parallel south is a circle of latitude that is 23 degrees south of the Earth's equatorial plane, about 50km north of the Tropic of Capricorn...

 and 24th parallels (including the city of Antofagasta
Antofagasta
Antofagasta is a port city in northern Chile, about north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region. According to the 2002 census, the city has a population of 296,905...

) for 25 years, except for agreed duties to be shared between the two countries..

Following extensive damage in the 1877 earthquake and tsunami, the municipal authorities in Antofagasta voted for a tax of 10 centavos
Bolivian boliviano
The boliviano is the currency of Bolivia. It is divided into 100 centavos. Boliviano was also the name of the currency of Bolivia between 1864 and 1963.-First boliviano:...

 per quintal
Quintal
Quintal may refer to:* Quintal , a unit of mass* Quartal and quintal harmony in music* Quintal, Haute-Savoie, a commune of the Haute-Savoie département in France* Stéphane Quintal, NHL ice hockey player...

 (approximately 46 kg (101.4 lb)) of nitrates exported to fund reconstruction of the town. The Chilean Antofagasta Nitrate & Railway Company
Ferrocarril de Antofagasta a Bolivia
The Ferrocarril de Antofagasta a Bolivia is a private railway operating in the northern provinces of Chile. It is notable in that it was one of the earliest railways built to the gauge of , with a route that climbed from sea level to over , while handling goods traffic totaling near 2 million tons...

, a major nitrate mining company in the region, refused to pay, backed by the Chilean government. This dispute resulted in the War of the Pacific
War of the Pacific
The War of the Pacific took place in western South America from 1879 through 1883. Chile fought against Bolivia and Peru. Despite cooperation among the three nations in the war against Spain, disputes soon arose over the mineral-rich Peruvian provinces of Tarapaca, Tacna, and Arica, and the...

, fought from 1879-84, by which Chile gained control of territory as far north as Tacna
Tacna
- Rail :Tacna is served by a cross-border standard gauge railway to Arica, Chile.It is also the location of the National Railway Museum of Peru.-Air:Tacna is served by the Crnl. FAP...

, including Bolivia's entire coastline.

Tectonic setting

Coastal regions of Peru and Chile lie above the convergent boundary
Convergent boundary
In plate tectonics, a convergent boundary, also known as a destructive plate boundary , is an actively deforming region where two tectonic plates or fragments of lithosphere move toward one another and collide...

, where the Nazca Plate
Nazca Plate
]The Nazca Plate, named after the Nazca region of southern Peru, is an oceanic tectonic plate in the eastern Pacific Ocean basin off the west coast of South America. The ongoing subduction along the Peru-Chile Trench of the Nazca Plate under the South American Plate is largely responsible for the...

 is being subducted
Subduction
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. These 3D regions of mantle downwellings are known as "Subduction Zones"...

 beneath the South American Plate
South American Plate
The South American Plate is a continental tectonic plate which includes the continent of South America and also a sizeable region of the Atlantic Ocean seabed extending eastward to the Mid-Atlantic Ridge....

 along the line of the Peru-Chile Trench
Peru-Chile Trench
The Peru-Chile Trench, also known as the Atacama Trench, is an oceanic trench in the eastern Pacific Ocean, about 160 kilometres off the coast of Peru and Chile...

. The rate of convergence across this boundary is measured at about 8 cm (3.1 in) per year. This boundary has been the site of many great megathrust earthquake
Megathrust earthquake
Megathrust earthquakes occur at subduction zones at destructive plate boundaries , where one tectonic plate is forced under another. Due to the shallow dip of the plate boundary, which causes large sections to get stuck, these earthquakes are among the world's largest, with moment magnitudes ...

s, in addition to events caused by faulting within both the subducting and over-riding plates.

Damage

The earthquake shaking caused significant damage over most of the coastal parts of the Tarapacá
Tarapacá Region
The I Tarapacá Region is one of Chile's 15 first order administrative divisions. It borders the Chilean Arica and Parinacota Region to the north, Bolivia's Oruro Department on the east, the Antofagasta Region on the south and the Pacific Ocean on the west. The port city of Iquique The I Tarapacá...

 and Antofagasta Region
Antofagasta Region
The II Antofagasta Region is one of Chile's fifteen first-order administrative divisions. It comprises three provinces, Antofagasta, El Loa and Tocopilla...

s. The tsunami caused a 10 m (32.8 ft) wave along about 500 km (310.7 mi) of coast, from Arica
Arica
Arica is a city in northern Chile. "Arica" may also refer to:Places* Arica and Parinacota Region, Chile* Arica Airport , Chile* Arica, Amazonas, town in Colombia* Rio Aricá-açu, tributary of the Cuiabá River south of Cuiabá, BrazilOther...

 in the north to Mejillones
Mejillones
Mejillones is a Chilean port city and commune in Antofagasta Province, Antofagasta Region. Its name is the plural form of the Spanish mejillón meaning "mussel", referring to a particularly abundant species and preferred staple food of its indigenous inhabitants. It is situated in the northern side...

 in the south. At Arica the water reached the cathedral. The hulk of the U.S. gunboat Wateree
USS Wateree (1863)
The first USS Wateree was a sidewheel gunboat in the United States Navy during the American Civil War.Wateree was built at Chester, Pennsylvania, by Reaney, Son & Archbold; launched on August 12, 1863; and commissioned at the Philadelphia Navy Yard on January 20, 1864, Comdr. F. E...

, which had been beached hundreds of metres inland by the final wave of the tsunami triggered by the 1868 Arica earthquake
1868 Arica earthquake
The 1868 Arica earthquake was an earthquake that occurred on August 13, 1868, near Arica, then part of Peru, now part of Chile, at 21:30 UTC. It had an estimated magnitude between 8.5 and 9.0...

, was moved several kilometres to the north along the coast and nearer the shoreline. The tsunami caused 5 deaths in Hilo, Hawaii, where 37 houses were destroyed. In Japan, on the Boso Peninsula
Boso Peninsula
thumb|Locationthumb|Landsat image with high-resolution data from Space Shuttle is a peninsula in Chiba prefecture on Honshū, the largest island of Japan. It forms the eastern edge of Tokyo Bay, separating it from the Pacific Ocean....

, many deaths were recorded.

Earthquake

The shaking lasted for five minutes at Caleta Pabellón de Pica, a coastal town 70 km (43.5 mi) south of Iquique
Iquique
Iquique is a port city and commune in northern Chile, capital of both the Iquique Province and Tarapacá Region. It lies on the Pacific coast, west of the Atacama Desert and the Pampa del Tamarugal. It had a population of 216,419 as of the 2002 census...

. The area of felt intensity of VIII on the Mercalli intensity scale
Mercalli intensity scale
The Mercalli intensity scale is a seismic scale used for measuring the intensity of an earthquake. It measures the effects of an earthquake, and is distinct from the moment magnitude M_w usually reported for an earthquake , which is a measure of the energy released...

 or greater, extended from about 50 km (31.1 mi) south of Arica to just south of Cobija
Cobija
The Bolivian city of Cobija is located about 600 km north of La Paz in the Amazon Basin on the border of Brazil and Peru. Cobija lies on banks of the Rio Acre across from the Brazilian city Brasiléia. Cobija lies at an elevation of ca...

. This indicates a rupture length of about 420 km (261 mi).

Tsunami

The tsunami affected the coasts of Peru and northern Chile and was observed across the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

, in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

, Samoa
Samoa
Samoa , officially the Independent State of Samoa, formerly known as Western Samoa is a country encompassing the western part of the Samoan Islands in the South Pacific Ocean. It became independent from New Zealand in 1962. The two main islands of Samoa are Upolu and one of the biggest islands in...

, Tonga
Tonga
Tonga, officially the Kingdom of Tonga , is a state and an archipelago in the South Pacific Ocean, comprising 176 islands scattered over of ocean in the South Pacific...

, Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...

, Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 and Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. At Arica eight separate large waves were recorded.

Future earthquake hazard

The rupture area of the 1877 earthquake has been recognised as one of the major seismic gap
Seismic gap
A seismic gap is a segment of an active fault that has not slipped in an unusually long time when compared with other segments along the same structure. Seismic gap hypothesis/theory states that, over long periods of time, the displacement on any segment must be equal to that experienced by all...

s on the plate boundary, known as the "Northern Chile Seismic Gap". The Mw = 7.7 2007 Tocopilla earthquake occurred at the southern edge of the gap, but is not considered to have necessarily reduced the risk of a great megathrust earthquake within this area. A recurrence period of 135 years has been estimated for great earthquakes along this part of the plate boundary, suggesting that a similar earthquake to the 1877 event is possible in the near future.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK