Chapter 3.- Earthquakes

Question 1

Tell Me about earthquakes in Japan: The impact of Tsunamis

Answer 1

Japan experiences many earthquakes because it is on the Pacific ring of Fire. In 2011 Japan was hit by its most powerful earthquake ever, which measures 9.0 on the Richter scale. The epicentre was about 70 km of the east coast of Japan. Here the Pacific plate is colliding with the Eurasian plate and sinking underneath it.

~ The earthquake raised the seabed by about 8 m. This resulted in huge tsunami waves up to 40 m in height crashing onto the coast

~ despite an early warning system with 1000 seismometers, sirens to warn people and huge tsunami walls, the waves travelled up to 10km inland, destroying many towns. Most of the 25,000 people who were killed were drowned.

~ The earthquake and tsunami also damaged roads, railways and industry and a dam collapsed. Electricity and phone lines were disrupted.

~ there were also serious problems in 2 nuclear plants when the cooling systems failed. People within a 20 km radius had to be evacuated because of the danger of radiation.

~ the main earthquake was followed by 100s of aftershocks

Question 2

How do you measure earthquakes

Answer 2

You measure earthquakes by using seismographs to measure the shocks or vibrations caused by earthquakes. The force of earthquakes is measured on the Richter scale.