Science learns from nature: how animals are teaching us to predict earthquakes
Researcher Dr. Rachel Grant and colleagues from the UK's Open University recently published an article in the "International Journal of Environmental Research and Public Health" that describes how semi-aquatic animals, like toads, are able to predict earthquakes.
In the paper, the researchers describe how stressed rocks within the earth's crust can release charged electrons from oxygen anion sublattice of silicate minerals that permeates the environment and makes subtle and brief changes to the surrounding environment. These subtle environmental changes include massive air ionization in the ionosphere and slight chemical changes to ground water as the water oxidizes to hydrogen peroxide. Dr. Rachel Grant and colleagues believe it is the chemical changes to the ground water that allow semi-aquatic animals to predict earthquakes [Int. J. Environ. Res. Public Health: Ground water chemistry changes before major earthquakes and possible effects on animals].
Of course, it has been known for some time that animals can predict earthquakes, with the earliest reports dated to around 370BC. Yet, it was not until the research of Dr. Rachel Grant and colleagues that scientists began to understand the mechanisms that allowed some animals to predict earthquakes, though it was generally accepted in learned circles that animals did not possess the ability to predict future events. Now, researchers are hoping that this information can be used to create a more reliable earthquake prediction system.
Our dismal failure at producing reliable earthquake prediction techniques demonstrates our need for more research. Foreshocks are one method that has led to correct predictions and saved lives, but only 50 percent of major earthquakes are preceded by foreshocks, and many foreshocks lead to false predictions that if used extensively could cause unnecessary, expensive and traumatizing evacuations. Researchers have also suggested that radon and electromagnetic signals, known as the VAN method, might be used to predict earthquakes. However, both methods are controversial and have been unable to provide consistent results.
A scientifically accepted idea is that fracturing silica releases colored light. This is a principle called triboluminescence, which states that when materials are pulled apart through the breaking of chemical bonds, they produce light. This has led some researchers to suggest using this principle to predict earthquakes. Yet, this principle has many problems. Light cannot travel very far underneath the ground. Plus, most earthquakes happen deep within the earth's crust. This means that to use this principle to predict earthquakes, a whole lot of detectors would need to be placed over large areas, very deep inside the earth. This means that light will not be predicting an earthquake near you.
So what kind of prediction system would this new research lead to?
A new earthquake prediction system, informed by this research, would lead to a three point prediction system that would possibly incorporate other methods, like rising ultralow frequency electromagnetic emissions, which can be detected from satellites, and seismic information, like foreshocks. The three detections points informed by Dr. Rachel Grant's research would include ionosphere ionization, chemical changes to ground water, and animal behavior.
To measure the ionosphere, scientists can use changes in radio waves, which are affected by the ionization of the atmosphere. Atmospheric ionization could also be detected by bouncing radar beams off electrons in the atmosphere. The radar beam scatters and creates an echo that can be used to determine the density of ionization in the atmosphere. The chemical changes to ground water is easy enough to measure with current technology, and animal behavior can be spotted by trained scientists and locals. A new prediction would rely on measuring the ionosphere and ground water, while maintaining a watch over the semi-aquatic animals. If any one of these is detected, the other two can be quickly checked.
This potential future prediction system would have several advantages. It does not rely on thousands and thousands of detectors drilled into the ground. Also, it could be accomplished with today's technology. If the semi-aquatic animals are any indication, this prediction system would allow warnings several days in advance. This should give people time to evacuate. However, the most important aspect about this possibly new earthquake prediction system is that it has been tried and tested for millions of years by our semi-aquatic friends.
Of course, there is a problem. There is no mention that detecting these free electrons in the atmosphere or water can allow scientists to predict the size of the earthquake. Moreover, scientists are unsure at what intensity animals able to detect and respond to an earthquake. If animals only respond to the most powerful earthquakes, this would leave animal behavior out of the prediction plan for many smaller but still dangerous earthquakes.
Hopefully, scientists will find correlations between the amount of free electrons in the atmosphere and water that will allow them to predict the size of earthquakes. Until then, more research will be needed if studies about how animals are able to predict earthquakes is ever to prove useful.