An earthquake is the sudden and sometimes very violent release of energy from the movement of the earth surface.
The surface is comprised of pates called tectonic plates. These plates are constantly moving into each other. As the pressure from them pushing on each other builds up, one of the plates has to give into the pressure. It can move up or down, or to one side or the other.
As they are moving and pushing and rubbing against each other, the rest of the earth shakes causing things on the earth to break and crumble.
One of the least expensive ways to build a home is with concrete. And, the most likely way to die in an earthquake is from something heavy falling on you. Many of the buildings in Haiti are build of concrete. And, since the area is historically not earthquake prone, the buildings aren't built for the shaking. Many people have been trapped under concrete rubble.
Many volunteers are needed to go and find people that may be covered or trapped by building debris. It will take many days to go through all the building rubble.
Haiti suffers much more during hurricanes than does the neighboring Dominican Republic.
According to the UNEP, the biggest issue is the building waste; some 40 percent to 50 percent of the buildings fell in Port-au-Prince and nearby towns. “Thousands of buildings suddenly become debris and this overwhelms the capacity of waste management,” says UNEP’s Muralee Thummarukudy.
The United Nations, the European Commission, Canada, Spain, The Netherlands, Germany, Denmark, Italy, Sweden and China have donated or pledged nearly US$38 million total, with the United States pledging an additional US$100 million. Also, Venezuela, Mexico, France, Britain, Iceland, Taiwan, Israel, Cuba, and neighboring CARICOM member countries are assisting with the supply of essential medical and food items, and professional and transportation services
Chile, Nicaragua, Spain, Guatemala, France, Mexico and Russia all rushed aid, mostly food and water, to Haiti on Jan. 13/China sent a 60-member search-and-rescue team with sniffer dogs.
Venezuela straight away sent 19 doctors and 10 firefighters who specialize in search and rescue along with 20 other experts and material aid.