Summary

Just to review, in the section we took an up close look at earthquakes. We made note of the following:

1. What seismic waves are and how they are generated
2. The different types of seismic waves and their characteristics
3. How seismic waves are used to give us a peak at the Earth’s interior
4. What causes earthquakes and where they occur
5. The different ways earthquakes are measured
6. How different material responds to an earthquake
7. The inability of scientists to predict earthquakes with any accuracy

Synthesis

I’m sure at least some of the reasons to study earthquakes go without saying. Geologists study earthquakes so they can better understand the cause of earthquakes which can in turn help with future predictions. Right now, there is very little ability to predict an earthquake. Geologists are interested in how the ground and different materials move during the earthquake. All of this information helps scientists and engineers understand what is required to build structures to withstand earthquakes. The hazards associated with earthquakes are some of the most dangerous and deadly as you saw in the videos at the beginning of the section.

So, why do California and Japan have so many earthquakes? California is located on the San Andreas Fault (one of many), which is a part of a transform plate boundary that is constantly moving. In the case of Japan, if you look back at the plate tectonics map, you will see Japan sits on top of three different tectonic plates that all moving in different ways. We now know that this movement is the main cause of earthquakes. As we continue to learn more about earthquakes, perhaps the next 9.0 earthquake will not do so much damage or claim so many lives.