Science contributes to society more and more with achievements. The newest theory states that earth cracks may transmit earthquake warning signs before earthquake strikes. This idea is still a theory, facts, and experiments have not proved it yet, but it may sound realistic. Some points stand by that theory. Could you imagine how perfect it would be to have a piece of information about the upcoming earthquake? It would give a great chance to follow emergency plans, and save our lives, as well as other precious things, and our loyal pets. Especially, if you live in an active seismic area such as California or Washington, that information would be most valuable for you. Predicting earthquake would help us to decrease human and economic losses to the minimum level and having earthquake warning signs not too much, at least minutes before would have such great positive consequences.
Fortunately, we have achieved to create early warning systems that alert you seconds before a big earthquake, but it will need more development.
Why there are earthquakes and faults?
The under levels of earth looks like hot, boiling matter called mantle, and above it there is ground. But there is an important thing to mention that land is not complete, it has faulted areas called tectonic plates. Stresses and other inner movements cause seismic activities and breaking of tectonic plates on the ground. For instance, the central part of the United States is located on the North American tectonic plate.
Pacific Ocean Plate and North American Plate borders are located in line from California to the Washington States. Generally, it looks like we live in big ships that sail on hot, boiling sea. As mentioned above, there are lots of tectonic plates, seven big, and twelve small, and many microplates. Borders of these tectonic plates meet active seismic areas, because all kind of seismic events, including earthquakes, and volcanic eruptions, happens here. In contrast, central regions of the tectonic plates are calm areas, and there is such a low probability of an earthquake.
Faults are cracking areas of tectonic plate borders.
They emerge as a result of the massive volume of rock displacements, and when they are sailing, moving actively under the forces of the mantle, it causes excellent striking earthquakes. Due to slip direction faults are classified into three types: dip-slip, oblique-slip, strike-slip. There is a great fault in California called San Andreas fault which is a reason of big California earthquake of 2004, of which the researchers claim that foreshocks were earthquake warning signs.
Magnitude, speed of the earthquake depend on sizes of faults. For example, length of the San Andreas fault is about 1,5 thousand kilometers, and depth is around 20 kilometers, and earthquakes are above eight magnitudes based on Richter scale are rare to expect in these areas. Conditions of matters, such as fluid, gas, hard also affect the power of the earthquake. Earthquakes are ground shocks that are caused by the rapid slipping of faults.
What does research say?
Scientists research on the early prediction of an earthquake based on signal emissions of fault areas. It says that fault areas issue earthquake warning signs weeks, months before an actual earthquake.
Discovery was published on the Geophysical Research Letters scientific journal on the fourth of November, 2018. It writes that smaller breaks occur before striking a great earthquake. Although it is beyond the current scientific achievements, foreshocks may help us to predict future primary shock. It is essential to state that besides the main shaking of an earthquake, there is foreshocks and aftershocks. Foreshocks are small magnitude quakes that strike before a rattling earthquake, and in contrast, aftershocks happen after the big one.
So, the research says that if low magnitude shocks occur along with the faulted areas, and if it is frequent in a particular location, it is a sign of the future approaching earthquake. Also, newly emerging breaks alongside faults and tectonic plate borders are probably symbols of an impending earthquake. Lead researcher of the New Mexico Los Alamos National Laboratory Paul Johnson says that slight failures along the broken ground would cause significant failure.
However, there are disagreements among the researchers of various scientific institutions.
Some scientists claim that that is not the best approach to forecast earthquake. They proof their notions by stating the fact that not in all earthquakes foreshocks are observed. That is somehow true not because it is impossible to follow them, but because of the reason that a single big shock may occur without any shocks before and after that.
Researches anticipate a better understanding of what activities happen before the earthquake by which they may help to reduce risk of losses to societies. Other restrictions to real-life implementation of that project are underground high stress, different level of density and temperature, states of matters, and case that almost all faults are filled up with moisture and fluids.
For researching foreshocks of the earthquake, scientists have created a lab model of faults: Tectonic plates, earthquakes, and seismic areas. It helps to simulate realistic quakes and breaks with the help of computers and other laboratory equipment. Crushing beads and rocks imitate actual faults by which researchers hope to contribute seismic science. They attempt to detect earthquake warning signs on laboratory with created simulations and want to implement these discoveries in possible samples.
Besides these, they wish to construct acoustic detectors on the active seismic areas, so that it would help to listen and detect alerts of an earthquake with small activities by processing these sounds. Also, researchers claim that density of earthquake detecting devices and seismographs would facilitate early warning process. It is clear that all start by observing and experimenting, later it would be implemented on real-life instances.
Is it possible to predict when an earthquake strikes?
With the latest scientific achievements and contributions of advanced supercomputer simulations yet it is not possible to precisely and accurately predicts when and where the earthquake would strike. But researchers study on that to find the best approaches and ways of predict earthquake. As mentioned above, a new study offers a theory that earthquake warning signs would help us to see where and when we may expect an earthquake.
However, seismology enables that we could get information about the probability of maximum magnitude of shocks in the area where we live. Even so, many maps have been developed that illustrates different expectations by taking researches on faults into account. It is interesting that Richter scale shows the maximum level of 12 magnitude earthquake because to expect shock with more than 12 magnitudes we need a fault that is bigger than sizes of the Earth, and limits make it impossible.
How effective are the earthquake early alert systems?
Geologists and seismologists have developed an earthquake early warning system that operating principle relies on detecting signals of an earthquake before it strikes. It requires a high number of seismographs networks that are connected to a database and processing center, of which quickly transforms this information and delivers it to certain earthquake early warning system users as loud alerts seconds before destructive waves of earthquake approach.
In the end, it is essential to mention that early alert systems would be considered pioneers in the earthquake prediction field. It may achieve to predict earlier by discoveries on earthquake warning signs.