Antarctica, mainly the East Antarctica was earlier regarded calmer region covered with a huge spread of ice some thousand feet thick with unidentified huge mountains. However, a study performed lately by a group of researchers seems to contradict the earlier presumption about the East Antarctica. The study revealed massive earthquakes taking place in the region.
As said by the researchers, the initial earthquakes in the region were identified in the year 1982. In the following 2 decades, around 8 earthquakes were found in Antarctica. However, the number drastically increased to near about twenty-seven in the year 2009.
Initially the number of seismic occurrences was thought to have been triggered by sudden changes in the geographical conditions of the region. Nevertheless, this study performed lately reasoned out differently. According to the seismologist Amanda Lough at the Drexel University, the instruments that were used for measuring seismic activities prior to the year 2009 were not capable of detecting seismic events properly. Almost all the earthquakes detected in the year 2009 were triggered by rifts. This means that in certain regions of Antarctica the rocks under the crust of the Earth were pulled apart, which gave rise to earthquakes.
Lough, the first author of this study, said, “The rifts provide zones of weakness that enable faulting to occur more easily, and it may be that the situation here is such that activity is occurring preferentially along these areas of pre-existing weakness.”
As a part of the study, which is regarded as the very first of its kind for substantially documenting seismic events, the involved researchers collected information dating back to the year 2009 by using wide range of sensors all over the area.
The seismic activities that were discovered in the region in 2009 were somewhat mild, as they their magnitude was not more than four when measured on the Richter scale. Even if it is assumed that the earthquakes were powerful enough to be felt by humans, the inferences of the study contradicts the previous theories about the Antarctica being a calmer region. The earlier conception that the immensely thick ice sheet of the Antarctica tends to suppress seismic activities, holds no good.
The observation of this new study has been published in the Nature Geoscience journal this week.