Local Scale Hazard - Caracas CS Flashcards
What hazards occur in Caracas?
Earthquake (zone 2), tropical cyclones (wind speeds of 76-141 km/h), tsunami hazard, storm surge hazard
Describe the location of Caracas in terms of plate boundaries:
Located on the intersection of the South American and Caribbean plates, Northern Venezuela (faces extreme seismological hazards)
How many times has an earthquake destroyed Caracas in the last 400 years?
3 times
When was the last major earthquake in Caracas, what were some effects?
Magnitude 6.5 earthquake in 1967 - killing an estimated 300 people and destroying 4 modern structures built for earthquake resistance
What happened in December 1999 in Caracas?
A month of rain on the north central coast of Venezuela included over 900 mm of rain within a 72 hour period, triggering landslides, mudflows and debris flows, killing an estimated 25000-250,000 people
What are the 3 main worries for Caracas?
Roads which cross over the fault line, utility (gas and water supply- pipes go over the fault line), high slope angles (up to 80% gradient) allow for immediate acceleration of surface fluids
What has happened to the population of Caracas since 1967?
Doubled, to 5 million people - with a population density of 12,000 people/km^2
What percentage of the Venezuelan population live in urban areas?
86% - making it the seventh most urbanised country in the world
What is the social class divide like in Caracas?
Social class divisions are huge in Caracas
They have lower, middle and upper class citizens
What sort of lifestyle do the upper class people have?
Gained their wealth/status in Venezuela through land ownership/ urban real estate. They own luxury homes in the valley and carrabean coast, these properties are likely to withstand earthquake hazard, far enough away from steep sided valleys to avoid landslide risk
What sort of lifestyle do the middle class people have?
They have developed largely in relation to the counties oil wealth and European immigration. Middle class housing occupies the centre core of the city, plus certain residential suburbs. These houses are smaller and less well constructed but use modern technology and good materials
What sort of lifestyle do the lower class people have?
Composed of labourers, servants and the unemployed, occupies the hillside shantytown, over looking the city from the west and south. These areas are hugely exposed to landslides, earthquakes and flooding, as well as little thought being given to safe construction
How is social reflection a risk in Caracas?
Population is clearly divided by wealth. Means that there are high risks of hazards. No construction company will pay for repairs so it’s unlikely poorer housing will have insurance. High unemployment means that many are without the income necessary to equip themselves and their property for possible hazards
Describe economic reflection of risk in Caracas:
The economy of Venezuela is based on oil . 50% of GDP is generated by oil sales and the rest is services. Being an urban area, Caracas is focused on services with banks, shops and national organisations based in the city.
How are governing bodies (political) helping to mitigate hazard risk?
- orienting a building so that its length is oriented parallel to the direction of flow will minimise the risk of building exposed to debris flow.
- orienting streets to generally parallel, the downslope direction of the fan helps them to serve as overflow channels, limiting potential damage to structures
- they have created strict “no build zones” but migrants build on them anyway as they cant afford anywhere else and there is little space
