1985 Pichilemu earthquake
Encyclopedia
The 1985 Pichilemu earthquake, also known locally as the Lago Rapel earthquake, was a 7.5 magnitude
earthquake
that occurred 50 kilometres (31.1 mi) northeast of Pichilemu
, O'Higgins Region
, Chile
on April 8, 1985 at 21:56:59 local time (01:56:59 UTC) at a depth of 37.8 kilometres (23.5 mi).
was registered on March 3, 1985 offshore Valparaíso
, Valparaíso Region
. It reached a maximum intensity of XI on the Mercalli intensity scale
. 177 people were killed, 2,575 injured, 142,489 houses were damaged and about a million people were left homeless. There was a long interruption on basic services, and the damage provoked by that earthquake was estimated to be more than 1,046 million US dollars.
The April 9 1985 Pichilemu earthquake occurred in the same fault area as the 2010 Pichilemu earthquake
, and is considered by University of Chile Seismological Service a thrust fault
-type interplate earthquake
.
. The earthquake lasted approximately three minutes according to The New York Times
.
It created damage in addition to that already caused by March 3 earthquake
in the Santiago-Valparaíso area.
The earthquake, measured in the Modified Mercalli intensity, reached magnitude VI in Curacaví
, La Calera
, Los Andes
, Peñaflor
, San Antonio
, Valparaíso
, and Viña del Mar
; and magnitude V-VI in Concón
, Constitución
, Curicó
, La Ligua
, Melipilla
, Papudo
, Pichilemu
, Puchuncaví
, Quilpué, and Villa Alemana
.
Although it has been considered by the news media as an aftershock of the main Santiago earthquake, according to Rosa Urrutia de Hazbún and Carlos Lanza Lazcano's book Catástrofes en Chile 1541–1992, the Pichilemu earthquake was a different and separate event.
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...
earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
that occurred 50 kilometres (31.1 mi) northeast of Pichilemu
Pichilemu
Pichilemu , originally known as Pichilemo, is a beach resort city and commune in central Chile, and capital of Cardenal Caro Province. It is located southwest of Santiago, the capital of Chile, and comprises an urban center and twenty-three villages, such as Ciruelos, Cáhuil, and Espinillo...
, O'Higgins Region
O'Higgins Region
The VI O'Higgins Region is one of Chile's 15 first order administrative divisions. It is subdivided into three provinces. It is named in honour of Bernardo O'Higgins Riquelme, one of Chile's founding fathers....
, 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...
on April 8, 1985 at 21:56:59 local time (01:56:59 UTC) at a depth of 37.8 kilometres (23.5 mi).
Background
A magnitude 8.0 earthquake1985 Santiago earthquake
The 1985 Santiago earthquake was a seismic movement registered on 3 March 1985 at 22:47 UTC . Its epicenter was located on the south coasts of Valparaíso Region, Chile, close to the beach of Algarrobo...
was registered on March 3, 1985 offshore Valparaíso
Valparaíso
Valparaíso is a city and commune of Chile, center of its third largest conurbation and one of the country's most important seaports and an increasing cultural center in the Southwest Pacific hemisphere. The city is the capital of the Valparaíso Province and the Valparaíso Region...
, Valparaíso Region
Valparaíso Region
The V Valparaíso Region is one of Chile's 15 first order administrative divisions.Valparaíso Region, 2006 With the country's third highest population of 1,539,852 million in 2002 and third smallest area of , the region is Chile's second most densely populated after the Santiago Metropolitan Region...
. It reached a maximum intensity of XI 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...
. 177 people were killed, 2,575 injured, 142,489 houses were damaged and about a million people were left homeless. There was a long interruption on basic services, and the damage provoked by that earthquake was estimated to be more than 1,046 million US dollars.
The April 9 1985 Pichilemu earthquake occurred in the same fault area as the 2010 Pichilemu earthquake
2010 Pichilemu earthquake
The 2010 Pichilemu earthquake , also known as the Libertador O'Higgins earthquake, was a 6.9 MW earthquake that struck Chile's O'Higgins Region on 11 March 2010 at 11:39 local time...
, and is considered by University of Chile Seismological Service a thrust fault
Thrust fault
A thrust fault is a type of fault, or break in the Earth's crust across which there has been relative movement, in which rocks of lower stratigraphic position are pushed up and over higher strata. They are often recognized because they place older rocks above younger...
-type interplate earthquake
Interplate earthquake
An interplate earthquake is an earthquake that occurs at the boundary between two tectonic plates. If one plate is trying to move past the other, they will be locked until sufficient stress builds up to cause the plates to slip relative to each other...
.
Damage and effects
Two people died of heart attacks after the earthquake; one in Santiago and another in ChillánChillán
Chillán is a city in the Biobío Region of Chile located about south of the country's capital, Santiago, near the geographical center of the country. It is the capital of Ñuble Province and, with a population of approximately 170,000 people , the most populated urban center of this province...
. The earthquake lasted approximately three minutes according to The New York Times
The New York Times
The New York Times is an American daily newspaper founded and continuously published in New York City since 1851. The New York Times has won 106 Pulitzer Prizes, the most of any news organization...
.
It created damage in addition to that already caused by March 3 earthquake
1985 Santiago earthquake
The 1985 Santiago earthquake was a seismic movement registered on 3 March 1985 at 22:47 UTC . Its epicenter was located on the south coasts of Valparaíso Region, Chile, close to the beach of Algarrobo...
in the Santiago-Valparaíso area.
The earthquake, measured in the Modified Mercalli intensity, reached magnitude VI in Curacaví
Curacaví
Curacaví is a city and commune in the Melipilla Province of central Chile's Santiago Metropolitan Region.-Geography and climate:Immersed among the hills of the coastal mountain range, Curacaví occupies an area of and borders the following communes: Casablanca, Quilpué, Lampa, Pudahuel, Maipú,...
, La Calera
La Calera
La Calera may refer to:*Argentina**La Calera, Argentina*Colombia**La Calera, Cundinamarca*Chile**La Calera, Chile*Mexico**La Calera Airport...
, Los Andes
Los Andes, Chile
Los Andes, founded in July 31, 1791 as Santa Rosa de Los Andes, is a Chilean city and commune located in the province of the same name, in Valparaíso Region...
, Peñaflor
Peñaflor, Chile
Peñaflor is a city and commune of the Talagante Province in central Chile's Santiago Metropolitan Region.-Geography:It can be found in the Chilean Central Valley approximately southwest of the metropolitan area of Santiago...
, San Antonio
San Antonio, Chile
San Antonio, meaning "Saint Anthony", is a major Chilean port and a commune in San Antonio Province, Valparaíso Region...
, Valparaíso
Valparaíso
Valparaíso is a city and commune of Chile, center of its third largest conurbation and one of the country's most important seaports and an increasing cultural center in the Southwest Pacific hemisphere. The city is the capital of the Valparaíso Province and the Valparaíso Region...
, and Viña del Mar
Viña del Mar
Viña del Mar , is a city and commune on central Chile's Pacific coast. Its long stretches of white sandy beaches are a major attraction for national and international tourists. The city is Chile's main tourist attraction. Known as "La Ciudad Jardín" , Viña del Mar is a Chilean Municipality located...
; and magnitude V-VI in Concón
Concón
Concón is a Chilean city and commune in Valparaíso Province, Valparaíso Region. It is known as the Gastronomical Capital of Chile and is a major tourist center known for its beaches, balnearios and night life.- Geography :...
, Constitución
Constitución, Chile
Constitución is a seaside resort, industrial city, minor port and commune in Chile, located in the Maule Region, Talca Province.-History:-8.8 magnitude 2010 earthquake:...
, Curicó
Curicó
Curicó , meaning "Black Waters" in Mapudungun , is the capital city of the Curicó Province, part of the Maule Region in Chile's central valley....
, La Ligua
La Ligua
La Ligua is a Chilean city and commune, capital of the Petorca Province in Valparaíso Region.The city is known for its textile manufacturing and typical Chilean pastry production.-Demographics:...
, Melipilla
Melipilla
Melipilla is a Chilean commune and capital city of the province of the same name, located in the Santiago Metropolitan Region southwest of the nation's capital...
, Papudo
Papudo
Papudo is a Chilean commune located in the Petorca Province, Valparaíso Region. The commune spans an area of .-Demographics:According to the 2002 census of the National Statistics Institute, Papudo has 4,608 inhabitants . Of these, 4,343 lived in urban areas and 265 in rural areas...
, Pichilemu
Pichilemu
Pichilemu , originally known as Pichilemo, is a beach resort city and commune in central Chile, and capital of Cardenal Caro Province. It is located southwest of Santiago, the capital of Chile, and comprises an urban center and twenty-three villages, such as Ciruelos, Cáhuil, and Espinillo...
, Puchuncaví
Puchuncaví
Puchuncaví is a town and commune in the Valparaíso Province of central Chile's fifth region of Valparaíso. It spans a coastal area of .-History:...
, Quilpué, and Villa Alemana
Villa Alemana
Villa Alemana is a city and commune in Chile's Zona Central. It was founded in 1896 by Italian and German immigrants. Villa Alemana is a part of the urban area known as Greater Valparaiso.- History :...
.
Although it has been considered by the news media as an aftershock of the main Santiago earthquake, according to Rosa Urrutia de Hazbún and Carlos Lanza Lazcano's book Catástrofes en Chile 1541–1992, the Pichilemu earthquake was a different and separate event.