EARTHQUAKE TODAY

WHAT IS THE LIVE MAP?






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The Earthquake Today live radar map shows all earthquakes which are happening or happened in the past all around the world. Every day happen a lot of earthquakes around the globe, but luckily only very few are very strong. Most of them aren’t even noticeable. The earthquake today map shows all of them, even the smallest shocks.

Earthquakes happen because the tectonic plates are always in movement. The earth is not only one single piece but consists of seven big tectonic plates and a lot of smaller plates.

There are four different types of plate movements:






The divergent plate boundary is where two continental plates drift apart from each other. As a consequence lava is able to come from the inside to the surface and by that it moves the plates even more apart. That`s also the reason for many volcanic eruptions worldwide. The African Riftvalley and the middle Atlantic back are examples for divergent plate boundary.



If two continental plates drift towards each other it is called convergent plate boundary. During this process one plate is pushed under the other one. The material which gets pushed in the interior of the earth melts during this process. Thereby the melted lava can break out through a volcano. A good example for this process is the oceanic plate which drifts under the continental plate. The reason for this process is because the oceanic plate is much heavier as the lighter and thicker continental plate.

There is another event which happens if two continental plates are drifting towards each other. But not always one plate goes under the other. Two continental plates can also arch upward and form mountains.






When two plates drift sideward in a different direction we speak about conservative plate boundary. This movement of earth plates causes a lot of earthquake today. During this process it comes to heavy tensions. These tensions then discharge as an earthquake. The best example for this plate shift is the San Andreas Fault. There is drifting the pacific plate sideward the North American plate.

The fourth plate movement is the passive plate boundary. It`s more a definition of boundary because on this boundaries the plates aren`t moving.

EARTHQUAKE TODAY

HOW ARE THEY MEASURED?

The Richter scale

The most popular technique to measure earthquakes is the Richter scale. This scale was invented by Charles Richter and Beno Gutenberg in 1935. Often you hear that the Richter scale goes from <2 (slight tremor) to 10 (global disaster), but actually the scale is open at the top. However the characteristics of the earth`s crust make an earthquake over 9,5 almost impossible, it would discharge before the value was exceeded.

Heavy earthquakes are not measured by the Richter scale because when they reach a value over 6,5 the scale loses their accuracy. You often hear in the news or read in the newspaper that the earthquake had a certain value according the Richter scale, but that isn`t true. Nowadays earthquakes are measured according the Moment magnitude scale. The Moment magnitude scale has a limit by 10,6. Scientists assume that at this value the earth crust would collapse.

The heaviest measured earthquake happened on the 22. May in 1960 in Chile. It reached a value of about 9,5 on the Moment magnitude scale. This earthquake costed 1655 people their life. Many people were able to save their lives because there were a lot of slighter tremors before. Thereby many were able to save themselves by leaving there houses. Otherwise the number of casualties would been much higher. The earthquake was followed by a huge tsunami. His almost 12 meter high waves devastated the city of Puerto Saavedra. Also the coast of Hawaii was reached by 10 meter high waves, and one day later reached a 5,5 meter high wave the coast of Japan.


Why is it so hard to predict earthquakes?

The progress in technology and development reaches new heights each year. But still it is not possible to predict earthquakes. Although there are some methods to indicate a possible earthquake, but this are no reliable information’s. The biggest problem is to determine the exact place and time. However, there is now a system to warn the population much faster when an earthquake happens. There are two types of waves which are sent out by an earthquake. At first there are the primary waves (P-Waves), these waves aren`t dangerous and do no damage. So if a seismograph recognizes these primary waves it is possible to quickly raise the alarm. The primary waves are then followed by the secondary waves (S-Waves), which are only half as fast. However this method allows to warn only a few seconds before the earthquake. It also depends on how far away the earthquake center is. But often only these few seconds can save many people’s lives.

Tsunamis, however, can be predicted a lot better. That is partly because the tsunami waves are much slower than earthquake waves. Most countries which could be hit by a tsunami are already in possession of some warning stations. For example buoys are used, so if a seaquake happened this buoys get the information and sent them immediately to the competent authority. This makes it possible to take immediate action. Furthermore there is often much more time until a tsunami hits the coast, often even several hours.

Also GPS technology is used to monitor the seabed and to detect fluctuations. Another warning signal that was observed again and again is the behaviour of animals. It has been reported several times that animals have gathered in unusual places before an earthquake happened. It seems that animals have a sense of predicting such natural disasters. There is a saying that says “when animals go crazy, run away from the sea and go to the highlands”. There are already many researchers who document the behaviour of animals and it was already possible to predict some earthquakes today.