Pampanga prone to ‘liquefaction’-A A +A
Friday, September 7, 2012
CITY OF SAN FERNANDO – Officials of the Philippine Institute of Volcanology and Seismology (Phivolcs) clarified that Pampanga could be affected by a massive earthquake through liquefaction.
Phivolcs director Renato Solidum Jr. said Thursday that liquefaction is “the process by which wet sediment starts to behave like liquid. It occurs because of the increased pore pressure and reduced effective stress between solid particles generated by the presence of liquid. It is often caused by severe shaking, especially that associated with earthquakes.”
Solidum, in interviews, said that liquefaction could happen after a strong earthquake, and several communities along the coastal areas in Metro Manila and nearby provinces could be affected.
He cited the coastal areas in the cities of Marikina, Pasig, Taguig, Caloocan, Malabon, Navotas, Marikina, Muntinlupa, Pasay, Las Piñas and the municipality of Pateros, plus the provinces of Pampanga and Nueva Ecija as susceptible to liquefaction.
Historically, the last time Pampanga was affected by an earthquake was in July 1990 when a magnitude 7.9 jolt hit Northern Luzon. Last August 7 at the height of the southwest monsoon flooding, an intensity 2 quake of tectonic origin was recorded in Clark.
Last year in an orientation for Pampanga officials and businessmen at Max’s Restaurant in Villa Del Sol, Solidum said structures near the Pampanga River and Pasig-Potero River as most prone.
As to earthquakes, he said that Pampanga needs to trace its history as a means of coming up with an earthquake response plan.
"The most that Pampanga may experience is an intensity-6 earthquake. But if you look back at its history from 1645 to 1880, many churches here have been destroyed. Much of the earthquakes here in Central Luzon come from the [Iba] Zambales, West and East Valley fault lines. But there is no need to worry if the building is good," said Solidum.
"Iyung tsunami naman, if it enters the Manila trench would take time to reach Pampanga. There would be time to prepare. But the most important thing here is to educate people starting at the barangay level, then moving ahead to communities and organizations," he added.
Published in the Sun.Star Pampanga newspaper on September 07, 2012.