Why is the Everest has become less and why such a cataclysmic earthquake in Nepal threatens to destroy Los Angeles with the “Hollywood,” says science department “Gazety.Ru».
A series of earthquakes that occurred in Nepal in late April and early May 2015, became the largest and most destructive since 1934. As a result of aftershocks of magnitude 7.8 points lost more than 9 thousand. People, 100 thousand. Suffered. About half a million houses were completely destroyed and 300 thousand. Seriously damaged.
Kathmandu is located on the site of the crust of 120 for 60 km. As a result of the earthquake to the region in just 30 seconds, shifted by 3 m to the south. Large earthquake in the Himalayan thrust are rare. In the twentieth century there was only four earthquakes of magnitude 6 or greater. The strongest of the four, Bihar-Nepal earthquake of magnitude 8 points took place in 1934. The study of earthquakes in 2015 and 1934′s showed that the basis of the two events lay buildup of tectonic stresses in the Earth’s crust.
With regard to the recognized UNESCO World Heritage site, it is only in Kathmandu they suffered seven. According to the Department of Archaeology of Nepal, it has been destroyed more than 30 palaces and temples.
For 20 years, Jean-Philippe Avak, a geologist at the California Institute of Technology, examines the Himalayas – the most active, land-based mining chain. Research conducted at the Department of Mines and Geology of Nepal and are aimed at the study of the formation of the mountains that lead to earthquakes, similar to what happened in the spring of 2015. Especially for this group of scientists led by Avak established in Nepal network GPS-stations that will track how the Earth’s crust moves during the quake. Through data obtained from satellites and seismic stations, Avakov and his colleagues managed to reproduce exactly what happened to the earth’s surface in April 2015. The results of research published in the journal Science and Nature Geoscience .
In the first study, scientists show that Nepalese earthquake occurred as a result of the front of the main thrust of the Indian plate dipping under the Eurasian at a rate of 2 cm per year. They found that the tremors began in the north-west, 75 km from Kathmandu and spread to the east at a speed of 2.8 km per second.
«From the point of view of geology Nepal – it is a place where we can expect large earthquakes. Thanks to the GPS-data, we know how for the past two decades, moving plates. That’s why this earthquake was not unexpected for us. Nevertheless, each earthquake brings surprises, “- said the study’s author.
The main surprise for the scientists was that lasted 40 seconds earthquake was different from previous ones. It turned out that instead of jerks who went to one another for a few seconds and destroyed small building, this time between the bursts was about 4-5 seconds. Such “slow” earthquakes pose a threat not just for high-rise buildings.
This explains the fact that the 60-meter tower, which survived the earthquake of 1934, this time collapsed.
In addition As a result of the earthquake became lower and the highest mountain in the world Everest (Qomolangma). According to US experts, the height of the mountain has decreased by approximately 2.5 cm. In this case, the Annapurna mountain range rose about 20 cm.
All of these sudden transfiguration are connected with the earthquake and the movement of tectonic plates. This Kathmandu Valley itself, researchers compared with a bowl filled with jelly. Moreover, such an earthquake with a long interval between the shocks otherwise transmit energy, and therefore do not fit into existing geologists view.
«I think that such an earthquake may occur not only in the Himalayas. Take, for Los Angeles. If it happens there, then these five-second shocks to the subsequent transfer of power would destroy a 50-storey building “, – concluded the researchers.
At the same time in Moscow “own” local earthquake is generating enough power to be noticed the population is almost impossible. How told «Gazeta.ru” deputy director of the Institute of Physics of the Earth Yevgeny Rogozhin, from time to time in Moscow felt earthquakes up to 5 points – a Carpathian earthquakes that regularly felt in Moscow as an echo from the rather distant seismic events .
For all existing seismic data, Moscow is a seismically safe areas. During the period of writing the history of Russia from the tenth century to the present time or in the annals of any other literary sources in Moscow, there was not a sufficiently strong local earthquake. There were no reported any significant local quake for all 70 years of almost continuous observations of seismic stanitsey “Moscow” (SSC “Moscow”), located in Pyzhevskii alley. 
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