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How shockwaves move through the earth

How Earthquakes Effect Us

A page on the causes and solutions of modern day earthquakes.

Causes of Earthquakes:

Natural Causes:

The most common cause of natural formed earthquakes are tectonic plate boundaries. There are two types of boundaries which cause earthquakes:

Subductive Boundary:

At a subductive boundary, two tectonic plates collide head on and one plate submerges underneath another plate. This is most common at boundaries where an oceanic plate meets a continental plate because oceanic plates are much more dense. What happens at these boundaries that can cause earthquakes is that sometimes the two plates do not move smoothly against one another. The plates can snag, when this happens the plates build pressure as the oceanic plate continues to try and push under. At any given moment this plate can break free causing an enormous release of pressure and energy. This release then sends shock-waves through the earth which is what creates the earthquake felt by mankind.

A political comic showing how conservationists often view fracking

Transform Boundary:

At a transform boundary, two plates shift past each other in a parallel motion. The way this creates earthquakes is very similar to the way that a subductive boundary can cause an earthquake. When these two plates are moving past each other they can sometimes snag. This snag creates the same buildup of pressure that can occur at subductive boundaries. When the two plates finally break free massive amounts of energy are released into the crust and down towards the core creating a violent earthquake in surrounding areas. The most well known transform boundary for creating earthquakes is the San-Andreas fault in California.

Induced Causes:

Fracking:

One of the most common causes of an induced earthquake is from things like oil drilling and mining. A common practice in this industry is fluid injection in order to break up materials below the surface of the Earth. By using fluid injection companies can save large amounts of money and time by not having to create large wells or mining areas. This practice however comes at a large risk, because it can disturb the land around the site of injection thus creating large amounts of movement and potential earthquakes. This makes it difficult for surrounding areas to prepare for an earthquake due to the speed in which an accident can occur.

Solutions:

Seismometer:

An example of a seismometer

A seismometer is a devices that measures movement in the ground below it. The issue with seismometers is that they are better for measuring and analyzing earthquakes than they are for detecting and having enough time to put out a warning. Since a seismometer measures movement in the ground below it, that means that often times the earthquake has already begun to disturb the ground in surrounding areas. This costs precious moments that people could be using to get to safety before the worst of the earthquake hits.

Gravimeter:

In an article posted on ScienceDaily.com, the University of Tokyo talks about different ways to measure an earthquake. The downfall to using seismic waves though is that by the time they reach a seismometer it is too late to warn the surrounding areas. This is why they began doing research into the use of a gravimeter in order to rapidly detect an incoming earthquake. Through the use of gravity waves, a scientist will now be able to detect a potential earthquake seconds before a seismometer would ever pick up a signal.

Conclusion:

These two sources are very important to each other for one large reason, they are both about speed. While tectonic plate shifts can be predicted and detected within reasonable time, the same does not hold true for an induced earthquake. When there are no seconds to spare, the research that is being conducted by the University of Tokyo could save hundreds or even thousands of lives. By using gravimeters, induced earthquakes could be predicted even just seconds before they happened, a time which is estimated to be able to give people a head start to safety. When an event like this happens every second counts, and thanks to this new research there might even be a few seconds to spare.