{{Use dmy dates|date=April 2014}}

{{Infobox earthquake

| title = 1985 Pichilemu earthquake

| date = {{Start date|1985|04|08|df=yes}}

| origintime = 21:56:59 [[UTC-4]]

| image =

| image alt =

| image name =

|map2 = {{Location map+ | South America

| places =

{{Location map~|South America|lat=-34.39|long=-72.01|label=Pichilemu|position=left||label_size=120|mark=Blue pog.svg}}

{{Location map~|South America|lat=-34.12|long=-71.51|marksize=40|mark=Bullseye1.png}}

| relief = yes

| width = 250

| float = right

| caption = }}

| caption =

| magnitude = 7.5 [[Moment magnitude scale|M_w]] <ref name="sig"/>

| intensity = [[Modified Mercalli intensity|MM]] VII

| depth = {{convert|37.8|km|mi|0|abbr=on}} <ref name="hist"/>

| location = {{coord|-34.12|-71.51|type:event|display=inline,title}}

| countries affected = Chile, Argentina

| tsunami = No

| casualties = 2 killed

}}

The '''1985 Pichilemu earthquake''' occurred with a [[moment magnitude scale|moment magnitude]] of 7.5 and a maximum perceived intensity of VII (''Very Strong'') on 8 April 1985 at {{Tooltip|21:56:59 local time|(01:56:59 UTC)}}.<ref>{{Cite web|url= http://politicaspublicas.uc.cl/media/agenda/material/20100325124410_Presentacion_Luis_Valenzuela.pdf|author=Luis Valenzuela|publisher=[[Universidad Católica de Chile]]|language=Spanish|title=Planificación Urbana en Zonas de Riesgo|date=14 April 2010|accessdate=11 September 2010|archiveurl=http://web.archive.org/web/20120312021435/http://politicaspublicas.uc.cl/media/agenda/material/20100325124410_Presentacion_Luis_Valenzuela.pdf|archivedate=12 March 2012|deadurl=yes}}</ref> The shock's epicenter was located {{convert|75|km|mi}} southwest of [[Santiago, Chile|Santiago]], [[Chile]],<ref name="sis">{{cite journal|title=Sismo del 8 de abril de 1985|year=1985|publisher=[[University of Chile]] Geological Service|language=Spanish|location=[[Santiago de Chile]]}}</ref> with a hypocentral depth of {{convert|37.8|km|mi|0|abbr=on}}.

==Earthquake==

[[File:1985 Lago Rapel earthquake.jpg|thumb|USGS ShakeMap of the 1985 Pichilemu mainshock]]

{{see also|Peru-Chile Trench}}

The 9 April 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]].<ref name="estudio">{{Cite web|url= http://ssn.dgf.uchile.cl/informes/congreso/A01-14.pdf|title=Estudio comparativo de los terremotos de subducción chilenos con los terremotos de subducción del norte, centro y sur de América|publisher=[[University of Chile]] Seismological Service|accessdate=12 September 2010|language=Spanish|date= 16–19 November 2005|location=[[Concepción, Chile|Concepción]], Chile|archiveurl=http://www.webcitation.org/6EkriB4YF|archivedate=27 February 2013|deadurl=no}}</ref>

The earthquake, measured in the [[Modified Mercalli intensity]], reached magnitude VI in [[Curacaví]], [[La Calera, Chile|La Calera]], [[Los Andes, Chile|Los Andes]], [[Peñaflor, Chile|Peñaflor]], [[San Antonio, Chile|San Antonio]], [[Valparaíso]], and [[Viña del Mar]]; and magnitude V–VI in [[Concón]], [[Constitución, Chile|Constitución]], [[Curicó]], [[La Ligua]], [[Melipilla]], [[Papudo]], [[Pichilemu]], [[Puchuncaví]], [[Quilpué]], and [[Villa Alemana]].<ref name="sis"/> The earthquake was felt throughout much of central Chile from [[La Serena, Chile|La Serena]] to [[Osorno, Chile|Osorno]]. It was also felt in [[Mendoza Province|Mendoza]], [[San Juan Province (Argentina)|San Juan]], [[San Luis Province (Argentina)|San Luis]], [[Córdoba Province (Argentina)|Córdoba]], [[Tucumán Province|Tucumán]], and [[Santa Fe Province (Argentina)|Santa Fe]] [[provinces of Argentina|provinces]] in Argentina.<ref name="hist"/>

Although it has been considered by the news media as an aftershock of the main Santiago earthquake,<ref name="estudio"/> 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.<ref>{{cite book|last1=Urrutia de Hazbún|first1=Rosa|last2=Lanza Lazcano|first2=Carlos|title=Catástrofes en Chile, 1541–1992|url=http://books.google.com/books?id=k64MAAAAYAAJ|year=1993|publisher=Editorial La Noria|location=[[Santiago de Chile]]|language=Spanish| accessdate= 13 September 2010 }}</ref>

===Damage and effects===

Two people died of heart attacks after the earthquake; one in Santiago and another in [[Chillán]].<ref name="hist"/><ref name="NY"/> The earthquake lasted approximately three minutes according to ''[[The New York Times]]''.<ref name="NY">{{Cite web|url= http://www.nytimes.com/1985/04/09/world/strong-quake-jolts-chile.html|title=Strong quake jolts Chile|archiveurl=http://www.webcitation.org/6EkrX0F6Y|archivedate=27 February 2013|deadurl=no|publisher=[[The New York Times]]|author=AP|date=8 April 1985|accessdate=8 September 2010}}</ref>

It created damage in addition to that already caused by [[1985 Santiago earthquake|3 March earthquake]] in the Santiago-Valparaíso area.<ref name="hist"/>

===Previous events===

{{main|1985 Santiago earthquake}}

A magnitude 8.0 earthquake was registered on 3 March 1985 offshore [[Valparaíso]], [[Valparaíso Region]].<ref name="sig"/> 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.<ref>{{Cite web|url= http://www.angelfire.com/nt/terremotosdeChile2/|title=Terremoto de 1985|publisher=Angelfire|language=Spanish|accessdate=12 September 2010| archiveurl= http://web.archive.org/web/20100804071652/http://www.angelfire.com/nt/terremotosdeChile2/| archivedate= 4 August 2010 | deadurl=no}}</ref> 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.<ref>{{cite news|url=http://www.emol.com/especiales/terremotos/chile.htm|title=Grandes Terremotos en Chile|work=[[El Mercurio]]|accessdate=12 September 2010|location=[[Santiago de Chile]]|archiveurl=http://web.archive.org/web/20120207175813/http://www.emol.com/especiales/terremotos/chile.htm|archivedate=7 February 2012|deadurl=no}}</ref>

==See also==

{{Portal|Pichilemu}}

* [[2010 Pichilemu earthquake]]

* [[List of earthquakes in Chile]]

==References==

{{reflist|refs=

<ref name="hist">{{Cite web|url= http://earthquake.usgs.gov/earthquakes/world/events/1985_03_03.php|title=Historic Earthquakes|publisher=[[United States Geological Survey]]|accessdate=8 September 2010|archiveurl=http://web.archive.org/web/20121104230038/http://earthquake.usgs.gov/earthquakes/world/events/1985_03_03.php|archivedate=4 November 2012|deadurl=no}}</ref>

<ref name="sig">{{Cite web|url= http://www.sismologia.cl/home/terrem.html|title=SISMOS IMPORTANTES Y/O DESTRUCTIVOS (1570 – Mayo 2005)|publisher=Sismología Universidad de Chile|language=Spanish|accessdate=8 September 2010|archiveurl=http://web.archive.org/web/20061231163803/http://www.sismologia.cl/home/terrem.html|archivedate=31 December 2006|deadurl=yes}}</ref>

}}

{{Earthquakes in 1985}}

{{Earthquakes in Chile}}

{{Pichilemu}}

{{DEFAULTSORT:Pichilemu earthquake, 1985}}

[[Category:Megathrust earthquakes in Chile|1985]]

[[Category:1985 earthquakes]]

[[Category:1985 in Chile]]

[[Category:History of Pichilemu|Earthquake, 1985]]

[[Category:History of O'Higgins Region|1985 Pichilemu earthquake]]