Earthquake off Sumatra caused a split Indo-Australian lithospheric plate in two. Such a conclusion is made by scientists, who published their observations in the journal Nature.
According to one of the study's authors, of the University of Utah Keith Koper, up to this point similar earthquakes ever recorded. It is part of the complex processes that occur during the split of the lithospheric plate. The formation of new plate boundaries will need a few million years, so it is likely that during this period is going to happen, at least, a thousand earthquakes of such power.
Scientists made this conclusion after studying the effects of a series of powerful aftershocks, the magnitude of which reached 8.6 — 8.7 points. They recorded at the island of Sumatra in April 2012.
Working to understand the cause of earthquakes, geologists, University of California found that they were not the epicenter at the joints of the lithospheric plates, as is usually the case, but somewhere within the Indo-Australian lithospheric plate. After studying the structure of boards found in the epicenter of four huge fault length of up to several hundred kilometers. According to researchers, this is evidence of a split plate half.
According to one of the researchers Thorne Lai, previously recorded faults on a relatively small scale. Now, an unprecedented event happened — split huge tectonic plates.
With scientists from California according to their Parisian counterparts. They found out that an earthquake caused uneven movement a splitting plate. At the moment, the Indo-Australian plate has split into "Australian" and "Asian" part. Both are moving towards the north-east. In this first part was faced with the Asian lithospheric plate near the Himalayas, which is somewhat slowing its movement. The second part began to sink under the rock, which is Sumatra.
According to data from the U.S. Geological Survey staff, split plate has an impact not only in the Asia-Pacific region, but also in other parts of the world. According to one of the researchers of the University of California Roland Bargmann, there have been quite a lot of major earthquakes around the globe, including the earthquake in Indonesia, California and Japan with a magnitude of 7 points. If their epicenter was located near the city, then the consequences could be catastrophic.
As it turned out, pushing off the coast of Sumatra, caused five times more earthquakes than expected at first. This effect was explained by the fact that the tremors in April caused small shifts in species other parts of the world, which then caused the new earthquakes. As explained Burgmann, sometimes these tremors occur in a few weeks.
Category: Natural disasters and the environment