Sometimes the Earth needs to readjust itself. When this happens we experience some pretty massive geological activity. Recently a large quake happened and changed a part of the Pakistan coastline. So, can an earthquake really just cause an island to pop up out of nowhere? Learn more in this week’s Question Your World Radio Report from the Science Museum of Virginia.
Earthquakes can be deadly and cause problems for millions of people, but they are a vital necessity for the Earth’s own internal on-goings. Our world appears solid and stable, but we’re totally moving around all the time. First of all we’re flying through space at a blistering speed of 67,062 miles per hour. While that orbital motion is happening the ground beneath us is literally moving around as well. The core of our planet is a big churning collection of iron-nickle alloy at a temperature that rivals the surface of the sun, hot stuff. All that internal motion allows for the plate tectonic motion on our planet to exist. These giant plates hold our surface world and they are constantly shifting around, sometimes we really feel it too.
For example, last week in Pakistan there was a large 7.7 magnitude quake that raised an entire island in the Arabian Sea. When these plates below our visible range shift, they sometimes buckle against one another and often slide on top or under each other causing all kinds of interesting geologic changes. The major mountains around the world are a result of shifting plates which continue to move to this moment! Similarly sometimes islands pop up due to an Earthquake. This island off the coast of Pakistan is not the first or last time we’ve seen this type of commotion from our planet.
In 2010 a massive 8.8 earthquake in Chile did quite a bit of shifting as well. This geologic activity had some pretty huge after effects in addition to altering the Chilean coast line forever. Sometimes these geologic internal adjustments have an impact that goes beyond the surface. For instance this Chilean quake actually was powerful enough to slow down the day by fractions of a second. Oh but wait, there’s more! A changed coast line and a slightly slowed down day are impressive, but this quake also was strong enough to shift the entire axis of the Earth by 3 inches! Sure this seems like a small distance, but consider what the quake had shifted, our entire planet!
Though these natural disasters are very dangerous they will happen as a natural part of the planet's evolution. A better understanding of these natural phenomena can help keep us safer and better prepared for these events when they happen. Regardless, these activities are a great reminder that we live on a dynamic and active planet that has a lot on its plate(s).
Article by Prabir Mehta, Science Museum of Virginia