Scientists at the Hyderabad-based CSIR-National Geophysical Research Institute have sounded warning about the impending danger of a massive earthquake in the Uttarakhand terrain, “including the Joshimath area” that has witnessed alarming levels of subsidence in the past weeks.
While the Himalayan region is known to be a seismic zone, the warning comes in the wake of the calamitous Turkey-Syria earthquake that has caused massive life loss – over 9,000 deaths counted till Tuesday.
“Uttarakhand falls in a seismic gap where a great earthquake is waiting to occur,” Dr Purnachandra Rao, chief scientist, Seismology, NGRI told DH.
A great earthquake – defined as a tremor of magnitude 8 or above – had occurred at Kangra in Himachal Pradesh in 1905 and at the Bihar-Nepal border in 1934. No major disturbance took place in between – ie Uttarakhand - for a century or so.
“Several studies, calculations show that the chances of a major earthquake are high along the stretch in between Himachal and Nepal, i.,e the whole of Uttarakhand,” says Rao.
“The stress built up due to tectonic plate movement in the Himalayas has to be released. We cannot predict when, but it is expected sooner or later in the form of an earthquake.”
NGRI, a premier research institute in solid earth, is also monitoring the Joshimath subsidence, a geological event that has kept the Uttarakhand authorities and the Centre on alert as they carry out evacuation efforts.
“We have deployed seismographs and the infra-sound instrument too, which is used to measure tectonic movements, to monitor the subsidence and are receiving real-time data here. We have observed some variations in the seismic signals at Joshimath. We are yet to analyze the information fully to come out with findings,” said Rao.
Another Hyderabad-based research institute, ISRO-National Remote Sensing Centre, had last month sounded alarm bells for the central and Uttarakhand state officials to act quickly on Joshimath's subsidence. NRSC detected a rapid subsidence of 5.4 cm, recorded in a span of just 12 days and confined to the central part of the Himalayan town.