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domingo, 7 de agosto de 2011

Tips to survive an earthquake

During the Earthquake:

  • If you are indoors, stay there. Quickly move to a safe location in the room such as under a strong desk, a strong table, or along an interior wall. The goal is to protect yourself from falling objects and be located near the structural strong points of the room. Avoid taking cover near windows, large mirrors, hanging objects, heavy furniture, heavy appliances or fireplaces.
  • If you are cooking, turn off the stove and take cover.
  • If you are outdoors, move to an open area where falling objects are unlikely to strike you. Move away from buildings, powerlines and trees.
  • If you are driving, slow down smoothly and stop on the side of the road. Avoid stopping on or under bridges and overpasses, or under power lines, trees and large signs. Stay in your car.   

After the Earthquake:

  • Check for injuries, attend to injuries if needed, help ensure the safety of people around you.
  • Check for damage. If your building is badly damaged you should leave it until it has been inspected by a safety professional.
  • If you smell or hear a gas leak, get everyone outside and open windows and doors. If you can do it safely, turn off the gas at the meter. Report the leak to the gas company and fire department. Do not use any electrical appliances because a tiny spark could ignite the gas.
  • If the power is out, unplug major appliances to prevent possible damage when the power is turned back on. If you see sparks, frayed wires, or smell hot insulation turn off electricity at the main fuse box or breaker. If you will have to step in water to turn off the electricity you should call a professional to turn it off for you.

Elastic rebound


The elastic rebound theory is an explanation for how energy is spread during earthquakes. As plates on opposite sides of a fault are subjected to force and shift, they accumulate energy and slowly deform until their internal strength is exceeded.

Volcanoes

A volcano is an opening, or rupture, in a planet's surface or crust, which allows hotmagmavolcanic ash and gases to escape from below the surface

jueves, 4 de agosto de 2011

Largest earthquakes of 1900

       
The following list compiles known earthquakes that have caused one or more fatalities since 1900. 

Volcano form from Japan's earthquake

Tsunami of Japan

the beggining of earth and the plates tectonic

Earthquakes

is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Theseismicity or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time. Earthquakes are measured using observations from seismometers.

There are three main types of fault that may cause an earthquake: normal, reverse (thrust) and strike-slip. Normal and reverse faulting are examples of dip-slip, where the displacement along the fault is in the direction of dip and movement on them involves a vertical component. Normal faults occur mainly in areas where the crust is being extended such as a divergent boundary. Reverse faults occur in areas where the crust is being shortened such as at a convergent boundary. Strike-slip faults are steep structures where the two sides of the fault slip horizontally past each other; transform boundaries are a particular type of strike-slip fault. Many earthquakes are caused by movement on faults that have components of both dip-slip and strike-slip; this is known as oblique slip.

Plate tectonics

 Is a scientific theory from Alfred Wegener ,which describes the large scale motions of Earth's lithosphere. The theory builds on the older concepts of continental drift, developed during the first decades of the 20th century.Was accepted by the majority of the geoscientific community when the concepts of seafloor spreading were developed in the late 1950s and early 1960s. The lithosphere is broken up into what are called tectonic plates. In the case of the Earth, there are currently seven or eight major 

Richter's scale

refers to a number of ways to assign a single number to quantify the energy contained in an earthquake..



 magnitude is a base-10 logarithmic scale obtained by calculating the logarithm of the amplitude of waves measured by a seismograph. An earthquake that measures 5.0 on the Richter scale has a shaking amplitude 10 times larger than one that measures 4.0.