April 11, 2012
Indonesian Earthquake: Update
Lawrence LeBlond for RedOrbit.com
Wednesday´s powerful 8.6-magnitude earthquake that struck off Indonesia´s western coast at 2:38 p.m. local time, was followed by fears of a tsunami, gripping a region that still had the 2004 tsunami -- one that ravaged numerous coastal communities along the Indian Ocean and killing more than 230,000 people -- fresh in their minds.
But hours after the fears of a tsunami subsided, a strong 8.2-magnitude aftershock hit the region sparking a new wave of panic and agencies issuing new tsunami alerts.
As the aftershock hit, residents were crying and screaming out “God is great” as they left their homes, fleeing into the streets. Others frantically searched for the separated loved ones.
The US Geological Survey (USGS) said the first quake was centered about 20 miles beneath the ocean floor and 270 miles from the Aceh province. That quake prompted the Pacific Tsunami Warning Center (PTWC) to issue a tsunami watch for several countries, including Indonesia, India, Sri Lanka, Australia, Myanmar, Thailand, the Maldives and other Indian Ocean islands, Malaysia, Pakistan, Somalia, Oman, Iran, Bangladesh, Kenya, South Africa and Singapore.
An initial wave measuring less than 3 feet high rolled in toward Indonesia´s coast following the alert, but there were no other signs of serious damage or danger.
But just as the region was taking a deep sigh of relief, the aftershock hit.
“We just issued another tsunami warning,” Prih Harjadi, from Indonesia´s geophysics agency, told TVOne in a live interview.
Residents in the island communities of Sumatra and Mentawai were warned to stay clear of the coasts.
Even though the type of earthquake these temblors were -- strike-slips -- the PTWC kept the watches up just in case. Strike-slip quakes do not produce vertical shifts of water, which is the key element of destructive tsunamis.
“When I first saw this was an 8.7 near Sumatra, I was fearing the worst,” said Roger Musson, seismologist at the British geological survey who has studied Sumatra´s fault lines, noting one of the initial reported magnitudes for the quake. “But as soon as I discovered what type of earthquake it was, then I felt a lot better.”
The first tremor lasted about 4 minutes and shook high-rise buildings in Singapore, Thailand, Bangladesh and India. It caused chaos in the streets of Aceh, forcing some patients to flee hospitals, some still attached to IV lines. The quake also caused power outages and other utility breakdowns.
Hours after the quake, people were still standing outside their homes, afraid to go back inside.
“I was in the shower on the fifth floor of my hotel,” Timbang Pangaribuan told El Shinta radio from the city of Medan. “We all ran out. ... We´re all standing outside now.”
He said one hotel guest was injured when he jumped from the window of his room.
India´s Tsunami Warning Center issued a warning for areas of eastern Andaman and Nicobar islands, and in Tamil Nadu, India, police blocked off the beach and used loudspeakers to warn people to leave the area.
So far no major damages or casualties have been reported from the areas affected by the quake, and no dangerous tsunamis have been recorded. However, experts said it is still too early to tell if the region is out of the woods.
Indonesia lies on a series of fault lines that makes the large island nation prone to volcanic and seismic activity. The December 26, 2004 9.1-magnitude earthquake that triggered a massive tsunami is one of the worst to hit the area in recent memory.