The Mexico City The Mexico City Earthquake of 1985Earthquake of 1985

What Were the Basic What Were the Basic Causes?Causes?

►The Michoacán gap.The Michoacán gap. Was a gap in the Cocos Plate that seismologist knew was ready to Was a gap in the Cocos Plate that seismologist knew was ready to

snap! snap!

►The Cocos Plate subducting under The Cocos Plate subducting under Mexico.Mexico.

What Made Mexico City What Made Mexico City Vulnerable to Mass Amounts of Vulnerable to Mass Amounts of

Destruction?Destruction?►LiquefactionLiquefaction

Mexico City is a very dangerous in terms of its local geology. It is Mexico City is a very dangerous in terms of its local geology. It is currently sitting on a 800 meter (2625 ft) lake bed made up of silt currently sitting on a 800 meter (2625 ft) lake bed made up of silt

and volcanic claysand volcanic clays

.

                                                            

Building FailureBuilding Failure

► design flaws in buildings:design flaws in buildings: soft first storiessoft first stories poorly joined building wingspoorly joined building wings odd-shaped buildings prone to twist on their odd-shaped buildings prone to twist on their

foundationsfoundations buildings of different heights and vibration buildings of different heights and vibration

frequencies that sat close together and bumped frequencies that sat close together and bumped into each other during the earthquakeinto each other during the earthquake

Compassionate Locals Rise to Compassionate Locals Rise to the Occasionthe Occasion

►Exacerbated social tensionsExacerbated social tensions►Social awarenessSocial awareness urban urban

developmentdevelopment semi-coerced semi-coerced government actiongovernment action

► http://video.google.com/videoplay?docid=-http://video.google.com/videoplay?docid=-7525846485083069161&q=mexico+city+earthqua7525846485083069161&q=mexico+city+earthquake+1985&hl=enke+1985&hl=en

Health, Education, and Health, Education, and EconomicsEconomics

►Collapse of major hospitalsCollapse of major hospitals

- Where did locals find aid?- Where did locals find aid?►Schools built on new and safe Schools built on new and safe

construction codesconstruction codes►Developing countriesDeveloping countries most vulnerable most vulnerable

to unpredicted natural disastersto unpredicted natural disasters

- under-insured businesses- under-insured businesses

- migration to US- migration to US

HousingHousing

►RHPRHP►Sympathetic and cooperative BankSympathetic and cooperative Bank►Government: Lethargic? Order? Government: Lethargic? Order?

Overall success?Overall success? riotriot

Government ResponseGovernment Response► Lack of preparednessLack of preparedness► Rescue brigades made up of civilians set out Rescue brigades made up of civilians set out

to help with no medical equipmentto help with no medical equipment► The national defense minister announced The national defense minister announced

the plan DN-III had been put into effect but the plan DN-III had been put into effect but no one understood what that meantno one understood what that meant

Government ResponseGovernment Response

►Outside countries provided reliefOutside countries provided relief►45 different countries poured in cash 45 different countries poured in cash

donationsdonations►Presidents of other countries traveled Presidents of other countries traveled

into the city to show supportinto the city to show support

Government ResponseGovernment Response

► City authorities revised building codesCity authorities revised building codes► Building modifications were implementedBuilding modifications were implemented

► Alarm system implemented by the Centro Alarm system implemented by the Centro de Instrumentacion y Registro Sismico, de Instrumentacion y Registro Sismico, A.C., known as SAS or the A.C., known as SAS or the Sistema de Alerta Sismica.Sistema de Alerta Sismica.