By Our Staff Reporter
Guwahati, April 20: A series of tremors in the region and elsewhere in the world, some of them very destructive, have left seismologists worried.
Northeast India, lying in the highest seismic risk zone V, has witnessed 29 earthquakes this year so far. Of these, nine were epicentered in Assam and five in the highly active Indo-Myanmar border region of Manipur.
A 6.9 magnitude quake struck Myanmar 135 km north-west of Mandalay on April 13. It shook eastern India, causing damage in many states of the region.
Over the last one month, there have been unusually active seismic activities across the globe, with a string of powerful earthquakes jolting Ecuador, Japan, Afghanistan and Indonesia, killing dozens of people and triggering several tsumi alerts.
Experts are not drawing quick conclusions, but some say it is "worrying".
"If strong quakes occur at quick succession, it is a bit worrying. Generally strong quakes do not occur in such quick succession," said Aboni Bhagowati of Gauhati University, referring to the quakes across the world.
Geologist Ranju Duara, however, allayed fears by pointing out: "Quakes cannot be predicted. No one can say if a quake would occur or not. But as the Northeast lies in a highly seismic zone, the people and the government should focus mainly on precautiory measures."
On average, 25-30 moderate to slight intensity quakes are recorded in the Northeast region by the Shillong observatory every year. Besides those, there are several others which are not recorded or are less than 3 on the Richter scale. Most of the quakes are between magnitude 4-5. The most common geological fault is the Indo-Myanmar fault in Manipur where most of the quakes are epicentered. Besides, there are other faults under Morigaon (Assam), Shillong, Indo-Bangladesh border and Aruchal.
The North Eastern region has experienced some of world's worst quakes, be it the Shillong quake of 1897 or the Assam quake of 1950, both measuring around 8.5 and reckoned to be two major quakes in human history, both in terms of intensity and destruction.
The quake in the Shillong plateau had left 1,542 people dead. The US-based GeoHazards Intertiol, in a report, had warned that if a magnitude 8.3 quake hits Shillong again, it will kill 60 times more people as were killed in 1897.
The reason, it says, is the replacement of single-story bamboo homes with multi-story, poorly constructed concrete frame structures, often on steep slopes, which have made the population much more vulnerable to high intensity temblors.