No danger from morning tremor

PHUKET CITY: An earthquake measuring 6.7 on the Richter scale, centered in the sea off the west coast of Sumatra this morning, posed little danger to Phuket, where its shock waves passed largely unnoticed.

The US Geological Survey website put the epicenter at 1.901ºN, 97.099ºE, about 120 kilometers west of the Sumatran coast, and at a depth of 30 kilometers.

Chamnong Chitpukdee, the new head of Southern Meteorological Center (West Coast) in Phuket, told the Gazette that the epicenter of the quake, which occurred at 8:52 am, was about 700 kilometers from Phuket. His office received a report that the magnitude of the quake was slightly higher, at 6.8.

“A 6.8-magnitude quake is regarded as only moderately dangerous. I don’t think there was any danger of a tsunami resulting from this earthquake, and we have received no reports of tsunami waves anywhere in the region,” he said.

Patong Deputy Mayor Chairat Sukbal said Patong Municipality had received a telephone call about the earthquake from the Nonthaburi-based National Disaster Warning Center. No evacuation orders needed to be issued, however, because the 6.8 magnitude fell below the 7.5-magnitude threshold considered necessary to produce a tsunami, he said.

“If it is not 7.5 Richter or greater, we don’t need to do anything. In the past, there were frequent tremors in Phuket, but nobody really followed up on them. But since the tsunami, the government has ordered its agencies to get any information about unusual seismic activity out to local authorities. That’s why we were informed,” he said.

Boonchai Somjai, head of the Phuket Provincial Office of Disaster Prevention and Mitigation, confirmed that his office was always prepared to deal with emergency situations. His office also uses a 7.5-magnitude event as its threshold for issuing warnings.

A much larger 8.7-magnitude quake centered off the west coast of Sumatra caused widespread panic of an impending tsunami when it hit late in the evening of March 28, but it too failed to produce any appreciable wave action.

The Richter scale is logarithmic, and therefore a 9.15-magnitude quake, such as occurred on December 26, 2004, is more than 100 times bigger than this morning’s 6.7-magnitude earthquake.