environmental hazards

Question 1

what is the cause of earthquakes?

Answer 1

Nearly all earthquakes take place at or near plate boundaries. Here the earth is unstable. From time to time pressure builds up between the plates. When the pressure becomes too high the plates suddenly slip causing an earthquake. This releases the pressure. This movement sends shockwaves through the rocks. The most damage occurs at the epicentre.

Question 2

how do seismologists predict earthquakes?

Answer 2

 Concentrating their attention on known active (moving) fault lines that have moved several times in recent years. The scientists look at the intervals in which the earthquakes have occurred and roughly work out when one may happen.
 Laser equipment to detect if the land has moved.
 Sound equipment to detect tremors.

Question 3

what is the death toll or an earthquake affected by?

Answer 3

 Developed countries have the money to design buildings that can withstand earthquakes. The people are often more prepared for earthquakes. Emergency services are quicker to respond.
 The time of day the earthquake hits. More people are killed during the day.
 The population density of an area. More people are killed in an area that has a high
population density.
 The ground that a town or city is built upon. Rock absorbs shockwaves better than soil.
 The remoteness of a town or city that is hit. This effects how quickly the emergency
services respond.

Question 4

what was the cause of the Haiti earthquake?

Answer 4

The quake occurred in the vicinity of the northern boundary where the Caribbean tectonic plate shifts eastwards by about 20mm per year in relation to the North American plate.

Question 5

what was the impact on the landscape and people after the Haiti earthquake?

Answer 5

 Approximately 230,000 people died as a result of the eruption
 250,000 residences and 30,000 commercial buildings had collapsed or were severely damaged.
 Landmark buildings were significantly damaged or destroyed, including the Presidential Palace, the National Assembly building, the Port-au-Prince Cathedral, and the main jail.
 Infrastructure necessary to respond to the disaster was severely damaged or destroyed. This included air, sea, and land transport facilities; and communication
systems
 More than 1,300 schools and 50 health care facilities were destroyed
 Water was contaminated with sewage
 Cholera was a major disease that spread throughout the homeless and injured

Question 6

what short term aid was used after the Haiti earthquake?

Answer 6

 Rescuing people from the rubble
 Treating injuries on surviving people.
 Setting up camps for the homeless
 Trying to provide clean water to control the diseases
 Provisions including food and blankets were sent from other countries.

Question 7

what long term aid was used after the Haiti earthquake?

Answer 7

 Reconnecting communication lines
 The EU gave $330 million and the World Bank waived the countries debt repayments for 5 years.
 The Senegalese offered land in Senegal to any Haitians who wanted it!
 Most of the camps had no electricity, running water, or sewage disposal, and the tents were beginning to fall apart.
 Between 23 major charities, $1.1 billion had been collected for Haiti for relief efforts, but only two percent of the money had been released
 One year after the earthquake 1 million people remained displaced
 The Dominican Republic which neighbours Haiti offered support and accepted some refugees.
 Medicines San frontiers, a charity, tried to help