More strong earthquakes likely in country: Expert
SINGAPORE — The devastating earthquake that struck Nepal’s Kathmandu valley on Saturday did not release all the stress that has been has accumulated since the last major earthquake in 1344, and the surrounding region is likely to experience other large earthquakes in the future, said Nanyang Technological University (NTU) Assistant Professor Judith Hubbard yesterday.
SINGAPORE — The devastating earthquake that struck Nepal’s Kathmandu valley on Saturday did not release all the stress that has been has accumulated since the last major earthquake in 1344, and the surrounding region is likely to experience other large earthquakes in the future, said Nanyang Technological University (NTU) Assistant Professor Judith Hubbard yesterday.
Likening the situation to compressing a spring, Asst Prof Hubbard, a scientist with the Earth Observatory of Singapore (EOS), said Saturday’s earthquake only released a little spring energy. The earthquake arose from two land masses pushing against each other after colliding millions of years ago.
“The amount of slip (how much a plate has moved in relation to another) that has been released in this earthquake is a lot less than the amount of slip that has accumulated in the last 700 years,” said Asst Prof Hubbard, a structural geologist with a focus on earthquake hazards. The amount of slip is measured by looking at plate convergence from GPS stations installed in India and Tibet, as well as seismic signals.
Prof Hubbard said subsequent earthquakes would more likely happen in neighbouring parts of the fault.
“We could see (a large earthquake triggered) further to the west, but less likely to see them to the east because that part released its energy in 1934,” she added. In 1934, Nepal experienced an earthquake with a magnitude of 8.1 about 10km south of Mount Everest.
NTU Professor Paul Tapponnier, also from the EOS, said that based on their ongoing research on tectonics, there seems to be a cyclic pattern of earthquakes that happens over 600 to 800 years in the region.
“Our studies have shown that if we are able to examine and discover what had happened in the past and when, we will be able to better understand which regions are safe and which are more at risk, allowing governments and communities to plan better for the future,” he said.
But Prof Hubbard said it is difficult to predict when exactly the large earthquakes could take place because “faults behave in a very irregular way”.
“We have very careful monitoring on these earthquakes in places such as California and Japan and we still can’t predict those events. In Nepal, we have much less information because it’s harder to get there, it’s very expensive to instal that kind of monitoring systems, so we know much less about the fault system,” she said.
As a country tight on resources, Nepal can target their research on ensuring that “most impactful buildings”, such as schools and hospitals, do not collapse during earthquakes. Developing plans on how people can access other regions of the country is also important, she added.