Earthquake in Indonesia triggers tsunami fear in India

A tsunami alert has been issued for Andaman and Nicobar islands following a powerful earthquake in the Indian Ocean near Indonesia. According to the United States Geological Survey (USGS), an earthquake measuring 8.6 on the Richter scale hit the Ocean off the coast of northern Sumatra at around 2:07 pm, IST.

 “We have issued warning for just two places in Andaman and Nicobar Islands–Indira point and Car Nicobar. A warning was also earlier issued for Kamotra island, but it has since been withdrawn because our models are showing it will not be hit by very high waves,” says Ravi Chandra, spokesperson for Tsunami Warning Center at the Indian National Centre for Ocean Information Services (INCOIS) in Hyderabad.

The warning was issued at 2:25 pm, IST. Chandra adds the tsunami waves were expected to hit the Andaman at around 3:00 pm, IST. “We’re trying to speak to officials on the island to confirm if the waves have hit already.”

Disaster management department in Andaman and Nicobar islands told Down to Earth (DTE) that the no waves have hit the islands so far. INCOIS had earlier said the tsunami waves might hit at around 3 PM. "Everything is normal. And tsunami waves have not hit any part of the state. Though warning has been issued to people living near the coast to move to the hilly areas."

Meanwhile, National Disaster Management Authority (NDMA) played down tsunami fears. Harsh Gupta, earthquake expert and a member of NDMA told DTE, "This is a strike-slip earthquake. These type of earthquakes do not create a vertical displacement. A vertical displacement is necessary to generate a tsunami. Hence, there will be no tsunami from this earthquake." Strike-slip motion occurs when two blocks of rock slide past each other at  fault line. The Sikkim earthquake of last year was a strike-slip earthquake.

Two aftershocks measuring 8.2 and 5.4 on the Richter scale hit the Indian Ocean off the coast of northern Sumatra. INCOIS said the aftershock do not pose any major threat, but alert has been issued for some coastal parts in Andaman and Nicobar Islands.

´╗┐INCOIS, however, later withdrew the tsunami warning. Its spokesperson said the warning was withdrawn because their real-time tracking of the tsunami waves clearly indicated that there won’t be any dangerous tidal waves hitting eastern coast of India.

Indonesia has also withdrawn the warning.

The Indian Ocean tsunami in 2004 off the west coast of Sumatra had caused widespread destruction and loss of life in Indonesia, Sri Lanka, Thailand and India.

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