As a geocacher, you will begin to see a lot of different ways that GPS can be used outside of the standard “I need directions to…” image that most people see. Many don’t realize just how much GPS is used in the real world, particularly in the area of scientific research. And one area that we are seeing an example of this is with earthquake research. With the recent devastating earthquakes in Japan, a really cool piece of GPS research gets a moment in the spotlight. Unfortunate that it takes such an event to highlight it, but useful information none-the-less.
The use of GPS technology for studying earthquakes isn’t new. It’s been commonly used in the design of seismographs for years to help more accurately measure seismic activity. There are earthquakes every single day of the year, a fact that is often forgotten by the general public. A fact that tends to be ignored when the media reports on the latest big earthquake. And a fact that is being ignored right now with all the “Supermoon causes earthquakes” bull#%&$ flying through the air right now. That’s an entirely different discussion so we’ll get back to the topic at hand.
Some may say “Wait a second Trip. If we had earthquakes every day, why isn’t it in the news? I don’t believe you.” Most earthquakes occur away from populated areas, with little to no affect on the general public. It’s only the ones that happen to be powerful enough that their effect is felt by the general public that make the news. Even then, only the ones that cause serious damage are widely reported beyond the local news. Check out the Iris Seismic Monitor. This site helps record seismic activity around the world. The monitor is rather self explanatory with the keys provided, but just in case you’re confused by it, let’s explain. The larger the circle, the more powerful the quake. Red circles occurred today. Orange occurred yesterday. Yellow between yesterday and two weeks ago. The time frame between two weeks ago and five years ago is represented by pink dots.
So why am I discussing this? Because I was recently alerted to another use of GPS in seismic research. There is a system of 1200 high-precision GPS stations set up around Japan called GEONET. These stations help to measure both horizontal and vertical displacement of the ground, as would be seen from seismic activity.
Begin basic Seismic Wave lesson: Seismic activity occurs in what scientists refer to as seismic waves. In a basic sense, seismic waves come in two basic types, Body Waves (which travel through the Earth) and Surface Waves (which travel along the surface of the Earth). Each type of wave has sub-types that display different properties, including speed. That last property is an important one in determining exactly where and when an earthquake occurs. Basic Seismic Wave lesson over.
Back to the stations. Remember that seismic activity is constant and produces earthquakes of varying intensities on a daily basis. Such a network would be valuable in seeing the long-term affects of earthquakes on the landscape. Is this why it was set up? I don’t know. But it is one use. The really interesting thing is that the data these 1200 stations recorded during the recent earthquakes in Japan was recently compiled and then visually represented. The resulting animation is pretty spectacular. This animation is pretty cool because you can actually see the wave-like action of the seismic waves. If you are scientifically inclined, the whole article is an interesting read on how the data was used. But if you just like pretty videos, then watch the clips found right at the start of the article. When watching it, remember that each little dot you see at the start is one of the 1200 GPS stations.
Why am I bringing this up? Well, I am a science teacher for those who DON’T already know and this is some cool science. But even more relevant is that it is cool science using GPS technology, which all of us are more familiar with than understanding seismology. For a technology originally designed for military use, it’s fun to see all the different ways it can be used. It only helps to underscore the value of educating students about GPS within the classroom too. They may eventually be using it in their jobs as an adult.