For each number on the scale that measures earthquakes, the earthquake’s energy increases by 30 times. In Norway, it is not unusual for earthquakes with a magnitude of 2. Then glass in cupboards shakes, and people and animals can clearly notice that something is happening. Earth plates in motion – When rounding 6, it is difficult to stand upright. And the closer you are to the epicenter, the worse it is. That’s what Anne Strømmen Lycke, director of the Norsar earthquake institute, says. She says that today’s earthquake in Turkey and Syria was registered at measuring stations all over the world. Also in Antarctica and Svalbard. Beneath the earth’s surface we find seven large and several small plates, so-called tectonic plates. These plates are in motion and sometimes collide with each other. It is along these plates that the earthquakes occur. Earth’s many tectonic plates. At irregular intervals, they bump into each other. Photo: Norsar Countries such as Turkey, Syria, Haiti and Japan are situated in such a way that they are often exposed to earthquakes, volcanic eruptions and tsunamis. Over 33,000 earthquakes last year In Turkey, 33,824 earthquakes were recorded last year, writes CNN Türk. Since the 16th century, the country has been shaken by as many as 23 earthquakes with a magnitude of 7 or more. And this Monday there were two earthquakes that were so powerful. One was measured at 7.8, the other at 7.5, the newspaper writes. Since Monday, there have been over 240 aftershocks, according to Turkey’s Disaster Management Directorate (AFAD). In the middle of the night, the most powerful earthquake measured in Turkey in over 80 years struck. In the hours that followed, there were dozens of noticeable aftershocks. – The African plate is slowly but surely coming north and pushing on the European plate. From the side comes a small plate called the Arabic plate. So Turkey is tricky, explains Strømmen Lycke. She says the country usually handles the many quakes they get, but calls today’s quake “incomprehensibly large”. These were earthquakes that sat relatively shallow in the ground. – Then they cause greater damage, she says. High risk of more earthquakes – Is there a high risk of earthquakes happening again in the same place? – Yes, it certainly is. That is what characterizes such active earthquake zones. So it is not a given that it will be as big, but what we see from such large earthquakes is that there will be a series of aftershocks that drop a bit in size, but it can last quite a long time. – The day the earthquake was incomprehensible, says Anne Strømmen Lycke, director of Norsar. Photo: Marit Kolberg / news She points out that the last earthquake in the afternoon occurred on another fault zone, approximately ten miles away from the first. Then there is reason to expect a separate series of aftershocks there. – So this, I’m afraid, will grow in scale. Several thousand people have lost their lives in Syria and Turkey after the earthquake on Monday. It is not possible to predict when they will arrive, so the rescue work will also be dangerous, she warns. – Why is it not possible to see that an earthquake is coming here, and to warn those who live there? – We would be happy to do that, replies the geologist. But despite much research, it has not been possible to predict such earthquakes. – It is an extremely difficult challenge. You know very well where earthquakes will occur, and you know the probability of what the maximum could be, but when is still a mystery. Facts about measuring earthquakes Earthquake strength is a measure of the energy released at the center of the earthquake. Today, most seismologists use the MMS scale (Moment Magnitude Scale), which is based on momentary measurement of strength. The MMS scale took over in the 1970s for the better-known Richter’s scale. The scales generally give corresponding values for smaller earthquakes, but the MMS scale gives more reliable results for the most powerful earthquakes. Both scales are logarithmic. For each whole number, the energy in the earthquake increases 31 times. An earthquake of magnitude 7.0 releases 900 times more energy than an earthquake of magnitude 5.0. An earthquake of 2.0 is considered the weakest that can be felt by humans. (Source: Ritzau, Reuters, USGS)
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This is why Turkey is often shaken by earthquakes – news Urix – Foreign news and documentaries
