Phivolcs Earthquake caused by stress buildup in faultline

	2/7/2012
Yesterday's earthquake was one of the strongest recorded in Cebu, said analyst Robinson Jorgio of the Philippine Institue of Volcanology and Seismology (Phivolcs) in Central Visayas. Check what's new in CEBU Now, click here He said Cebu is not prone to earthquakes since the faultlines that run along the province are inactive. “There's no significant earthquake data in Cebu. Most of our earthquakes have low magnitude,” Jorgio said. The quake that struck part sof Central Visayas was tectonic in nature, meaning it was caused by the buildup of stress on the tectonic plates in Negros Oriental. “It releases a large amount of energy that causes the vibration in the ground, which we call an earthquake,” said He said yesterday's earthquake was caused by a “blind fault,” a faultline they have not yet identified. Jorgio said blind faults are normal since the “lithosphere,” the solid portion between the crust and the upper mantle plates move continually. Earthquakes are caused when friction puts stress on the tectonic faults. The epicenter was near Tayasan, Negros Oriental, about 100 kilometers across the sea from the center in Lapu-Lapu City. Jorgio said the tremor lasted for more than 16 seconds. Other areas in Sibulan and Dumaguete City were also heavily affected in Negros Oriental. Jorgio said Phivolcs hasn’t recorded any earthquake in the country whose epicenter is in Cebu. He said the country experiences at least 20 earthquakes daily since the country is within the Pacific Ring of Fire, a zone with frequent earthquakes and volcanic eruptions. The Philippine Red Cross advised that during earthquakes, people should not panic. Shield yourself from falling debris by ducking under a table or other sturdy furniture. Move away from glass windows. When outside in open ground, people should find a safe spot to dodge electric posts, trees or collapsing walls. In riding a vehicle, one should not pass under flyovers and bridges. Seek higher ground to avoid the danger of a tsunami. /Candeze R. Mongaya, Reporter