TSUNAMIS: RP'S EXPERIENCE
MANILA, December 29, 2004 (STAR) By Felix De Los Santos - The death and destruction from the tsunamis that hit Asia on Sunday has its echoes in a local calamity that hogged headlines nearly three decades ago.The same unimaginable terror and sorrow for lives lost and property destroyed were also experienced by residents of some parts of Mindanao in 1976.
A few minutes after midnight of Aug. 17, a magnitude 7.9 earthquake, generated by the Cotabato Trench, struck offshore and spawned a tsunami that devastated more than 700 kilometers of coastline bordering the Moro Gulf in the North Celebes Sea.
The cities and provinces of Cotabato bore the brunt of the earthquake, while the tsunami unleashed its fury on the provinces bordering the Moro Gulf, especially the shores of Pagadian City.
[http://www.phivolcs.dost.gov.ph/Earthquake/1976MoroGulfEQ/moro76.html]
In its website, the Philippine Institute of Volcanology and Seismology (Phivolcs) described the "massive destruction" and "great loss of lives" in the aftermath of the earthquake and the tsunami that "contributed immensely to the devastation."
"After the sea spent its fury and rolled back to its natural flow, thousands of people were left dead, others homeless or missing and millions of pesos lost with the damage on properties that included establishments for residential and commercial use and also bancas used for livelihood by hundreds of families," it said.
The toll: 4,791 dead, 2,288 missing and 9,928 injured.
The Moro Gulf earthquake is described by Phivolcs as "largest tsunamigenic earthquake to have occurred in Mindanao" in the two decades preceding 1976.
The earthquake was felt at Intensity 7 in Cotabato City, Jolo, Sulu and Zamboanga City, and at Intensity 6 in Basilan City, Pagadian City, Dipolog City and Malaybay in Bukidnon. The quake was felt at Intensity 4 as far away as Dumaguete City and Cebu City.
Seismic records showed the quake was preceded by six "foreshocks" that had epicenters in the same area as the main shock. The quake was followed by more than 40 aftershocks, some as powerful as Intensity 4 in the Rossi-Forel scale.
In contrast, the tsunamigenic earthquake that hit South Asia was not felt in most of the affected areas, as its epicenter was deep beneath the Indian Ocean.
But as in Sunday’s quake, much of the death and destruction caused by the Moro Gulf quake was blamed on the tsunami that followed the main shock.
Surveys after the event suggested the tsunami accounted for 85 percent of the deaths, 95 percent of the missing and 65 percent of the injured.
Will the Philippines be affected by the South Asia tsunami?
"No" was the reassuring answer of Phivolcs seismologist Ric Mangao.
"The Philippines will not be affected by the South Asia tsunami because of our location. Big islands of Malaysia, Thailand and Indonesia serve as barrier against the tsunami path," he said.
Mangao said the waves of the tsunami had already dissipated and would no longer have any significant effect unless another quake occurred that is strong enough to generate a tsunami.
Without sounding alarmist, Mangao did not dismiss the possibility of a similar earthquake occurring in the fault system traversing the ocean floor underneath the Philippine archipelago.
He said it is best for people living along coastal areas to take the necessary precautions and heed warnings from government agencies and — in the absence of such announcements — from Mother Nature herself.
"Should people notice a sudden and unusual drop in the sea level, they must seek higher grounds immediately," Mangao said.
Reported by: Sol Jose Vanzi
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by PHILIPPINE HEADLINE NEWS ONLINE
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