By ARTHUR L. ALLAD-IW
www.nordis.net

We were having our last class on Friday just past 9 AM when there was a strong quake. Without showing I was nervous, I told my 20 or so students in History to go out slowly, not to panic, and secure themselves outside the Easter College building. Obediently they did. Outside, I shared some of our experiences in the 7.8 magnitude earthquake of 1990, before we returned to our classroom after 20 minutes or so.

That experience was not only a venue to share the experiences that we had on July 16, 1990 where thousand of lives and billions worth of properties and infra-structures were lost. Again, I reviewed my materials on geological hazards, particularly the natural ones, like the earthquake.

Our country is located in the Pacific belt where there are numerous active faults and trenches and numerous volcanic belts and active volcanoes. As such, we are located in a geologic hazardous area. Very particular natural hazard that we usually experience is the earthquake because of the nature of our location.

Earthquake is defined by the MGB-DENR as a weak to violent shaking of the ground produced by the sudden movement of the rock materials below the earth’s surface. There are two kinds: the Tectonic and Volcanic. Tectonic earthquake is produced by sudden movement along fault lines and plate boundaries. Volcanic earthquake on the other hand is produced by movements of magma beneath volcanoes.

The earthquake at 9:18 AM on November 16 had a magnitude of 4.0. It seems to be tectonic in character as concerned government agency says the epicentre was in Tuba, Benguet. So it is near Baguio and we experienced the strong shake despite being 4.0 in magnitude and I suppose it is caused by the Tuba fault line.

Interesting to note is the fact that Baguio City and the Cordillera are surrounded by fault lines. Baguio is surrounded by the Digdig fault line traversing the Benguet, Viscaya, and Pangasinan; the San Manuel faultline, the Tebbo faultline, and the Tuba fault line. The nearest in Baguio City are the Tebbo and Tuba fault lines. Tebbo fault line is located 10 kilometers southwest of Baguio and is 70 kilometer long while the Tuba fault line is located in the west of Baguio approximately 5 kilometers away and is alleged to be 50 kilometers long added the MGB-DENR documents.

So in the Friday experience that we had, it was traceable to the Tuba fault line. The fact also shows that since we are surrounded by at least four faultlines, quakes are naturally to be experience by the city.

Alas, even fault lines surround our region too. Like the above faultlines, these are earthquake generators surrounding our region. We have the Casiguran fault, the Manila Trench, and the East Luzon (through the Philippine trench).

Of course these faultlines are natural and the quakes generated are natural too. But it does not mean that these cannot be mitigated. In fact, since our place is identified as such geologic hazards projects by the government should be geared to mitigate their effects. The question is: does the government consider our natural situation in their infra-projects? The answer my friend, is clear on Bob Dylan’s song, it is blowing in the wind! # nordis.net