HYDERABAD: Tuesday forenoon’s earthquake in Nepal has raised several questions among seismologists at the National Geophysical Research Institute. Terming it ‘exceptional’, they believe it would help them in their assessment of the April 25 earthquake in Nepal that claimed over 7,000 lives.
Scientists believe the bigger the earthquake, the more the number of aftershocks. “Most of the aftershocks of the April 25 earthquake have been between 5 and 6.5 magnitude. It may continue for up to two months. But Tuesday’s aftershock was very close to the original earthquake in terms of magnitude but it has its epicentre in the opposite direction, that is the eastern edge of the plate. It has also occurred very close to the epicentre of the 1984 Bihar-Nepal earthquake, the worst in the region at 8.4 magnitude,” said N Purnachander Rao, Principal Seismologist at the CSIR-National Geophysical Research Institute (NGRI).
NGRI, which undertakes several seismic related projects in the Indo-Gangetic plains and the Himalayan region, has post-April 25 taken up a first of its kind study on the magnitude, epicentre and pattern of aftershocks in order to prepare a countrywide “acceleration map”.
It has installed GPS instruments along the fault zones of the earthquake-hit region to understand the movement of the blocks post the event. The study is expected to bear fruit in a couple of months. The collision of Indo-Eurasian plates makes the region an active seismic zone prone to big earthquakes.
“We are still studying this particular earthquake of April 25. The significance of our study is that we will be able to understand the ground acceleration due to this earthquake around the seismic zone. We will be able to have an acceleration map, for the first time,” said Dr Rao. According to him, acceleration here means that the ground impact on building structures and projects could be understood.
“As of today, we do not have any technology to predict earthquakes which makes it important for us to build structures which can withstand the pressure. If we know how the buildings would respond to a particular impact, we could establish better parameters for construction and designs for future projects,” he pointed out adding that there exist buildings in Tokyo that could withstand an earthquake with a magnitude of 8. “Our lack of awareness and indifference towards technological advancements are the cause of loss of lives during an earthquake,” he rued.