The 1877 Iquique earthquake occurred at 21:16 local time on 9 May (0:59 on 10 May UTC). It had a magnitude of 8.5 on the surface wave magnitude scale. Other estimates of its magnitude have been as high as 8.9 and 9.0 (based on the size of the tsunami). It had a maximum intensity of XI (Extreme) on the Mercalli intensity scale and triggered a devastating

tsunami A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater exp ...

. A total of 2,385 people died, mainly in Fiji.

Historical context

Affected areas in what was then part of Bolivia, but is now the Antofagasta region of Chile, had during this period been subject to the Atacama border dispute between the two countries. Under the 1874 boundary treaty between Bolivia and Chile, the border between the two nations as of 1877 followed the

24th parallel south The 24th parallel south is a circle of latitude that is 24 degree (angle), degrees south of the Earth, Earth's equator, equatorial plane, about 60 km south of the Tropic of Capricorn. It crosses the Atlantic Ocean, Africa, the Indian Ocean, ...

. The terms of that treaty required that Bolivia not levy taxes on Chilean companies mining nitrates between the 23rd and 24th parallels (including the city of

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 2015 census, the city has a population of 402,669. After the Spanish American wars ...

) 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 per

quintal The quintal or centner is a historical unit of mass in many countries which is usually defined as 100 base units, such as pounds or kilograms. It is a traditional unit of weight in France, Portugal, and Spain and their former colonies. It is com ...

(approximately ) of nitrates exported to fund reconstruction of the town. The Chilean Antofagasta Nitrate & Railway Company, 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 The War of the Pacific ( es, link=no, Guerra del Pacífico), also known as the Saltpeter War ( es, link=no, Guerra del salitre) and by multiple other names, was a war between Chile and a Bolivian–Peruvian alliance from 1879 to 1884. Fought ...

, fought from 1879 to 1884, by which Chile gained control of territory as far north as

Tacna Tacna is a city in southern Peru and the regional capital of the Tacna Region. A very commercially active city, it is located only north of the border with Arica y Parinacota Region from Chile, inland from the Pacific Ocean and in the valley of ...

, including Bolivia's entire coastline.

Tectonic setting

Coastal regions of Peru and Chile lie above the

convergent boundary A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a ...

, where the Nazca Plate is being

subducted Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...

beneath the South American Plate along the line of the

Peru–Chile Trench The Peru–Chile Trench, also known as the Atacama Trench, is an oceanic trench in the eastern Pacific Ocean, about off the coast of Peru and Chile. It reaches a maximum depth of below sea level in Richards Deep () and is approximately long; ...

. The rate of convergence across this boundary is measured at about per year. This boundary has been the site of many great

megathrust earthquake Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthqu ...

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 San Lorenzo de Tarapacá, also known simply as Tarapacá, is a town in the region of the same name in Chile. History The town has likely been inhabited since the 12th century, when it formed part of the Inca trail. When Spanish explorer Diego ...

and

Antofagasta Region The Antofagasta Region ( es, Región de Antofagasta, ) is one of Chile's sixteen first-order administrative divisions. The second-largest region of Chile in area, it comprises three provinces, Antofagasta, El Loa and Tocopilla. It is bordered t ...

s. The tsunami caused a wave along about of coast, from

Arica Arica ( ; ) is a commune and a port city with a population of 222,619 in the Arica Province of northern Chile's Arica y Parinacota Region. It is Chile's northernmost city, being located only south of the border with Peru. The city is the capita ...

in the north to

Mejillones Mejillones is a Chilean port city and commune in Antofagasta Province in the Antofagasta Region. Its name is the plural form of the Spanish meaning " mussel", referring to a particularly abundant species and preferred staple food of its indige ...

in the south. At Arica the water reached the

cathedral A cathedral is a church that contains the '' cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominatio ...

. The hulk of the U.S. gunboat ''Wateree'', which had been beached hundreds of metres inland by the final wave of the tsunami triggered by the 1868 Arica earthquake, was moved several kilometres to the north along the coast and nearer the shoreline. The tsunami caused 2,000 deaths in Fiji, and another 5 in Hilo, Hawaii.

Characteristics

Earthquake

The shaking lasted for five minutes at Caleta Pabellón de Pica, a coastal town south of

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 Pampa del Tamarugal, which is part of the Atacama Desert. It has a population of 191, ...

. The area of felt intensity of VIII on the Mercalli intensity scale or greater, extended from about south of Arica to just south of

Cobija Cobija is a city in Bolivia, capital of the department of Pando, is located about 600 km (373 mi.) north of La Paz in the Amazon Basin on the border with Brazil. Cobija lies on the banks of the Rio Acre across from the Brazilian ci ...

. This indicates a rupture length of about .

Tsunami

The tsunami affected the coasts of Peru and northern Chile and was observed across the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...

, in Australia,

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Samoa Samoa, officially the Independent State of Samoa; sm, Sāmoa, and until 1997 known as Western Samoa, is a Polynesian island country consisting of two main islands ( Savai'i and Upolu); two smaller, inhabited islands ( Manono and Apolima); ...

Tonga Tonga (, ; ), officially the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesian country and archipelago. The country has 171 islands – of which 45 are inhabited. Its total surface area is about , scattered over in ...

, Fiji,

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

and Japan.An oceanic perturbation
Otago Daily Times, Issue 4753, 12 May 1877, Page 2 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 A seismic gap is a segment of an active fault known to produce significant earthquakes that has not slipped in an unusually long time, compared with other segments along the same structure. There is a hypothesis or theory that states that over long ...

s on the plate boundary, known as the "Northern Chile Seismic Gap". The = 7.7

2007 Tocopilla earthquake The 2007 Tocopilla earthquake occurred on November 14 at . Its epicenter was located between Quillagua and Tocopilla, affecting the Tarapacá and the Antofagasta regions in northern Chile. The earthquake had a moment magnitude of 7.7 and lasted a ...

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. In 2005, a recurrence period of 135 years was estimated for great earthquakes along this part of the plate boundary, suggesting that a similar earthquake to the 1877 event was likely in the early 21st century. The

2014 Iquique earthquake The 2014 Iquique earthquake struck off the coast of Chile on 1 April, with a moment magnitude of 8.2, at 20:46 local time (23:46 UTC). The epicenter of the earthquake was approximately northwest of Iquique. The mainshock was preceded by a numb ...

struck in the same seismic gap with a magnitude of = 8.2.