Intensity vs. magnitude
Be more conscious of an earthquake’s intensity rather than its magnitude as the intensity depicts the strength of the shaking.
This was Department of Science and Technology (DOST) Undersecretary Renato Solidum Jr.’s reminder to the public as the country underwent a nationwide simultaneous earthquake drill with the Cebu provincial government spearheading the activity (see separate story) on Friday.
“The intensity is what you feel on the surface,” he said.
“By analogy, yung bombilya ng ilaw, wattage, yun yung magnitude. Yung intensity ng ilaw, maliwanag sa ilalim ng bombilya, pag malayo, madilim, lower yung intensity. So the intensity is different in different places away from the earthquake,” he said.
According to Solidum, there are several identified major faults in Cebu, including those located in Daanbantayan and Bogo in the north and the Cebu Fault System in the central part, which consist of at least five “traces” or paths that the faults traverse, that pass through Cebu City, Danao City, Balamban, Toledo City, Talisay City, Minglanilla and Naga City. While in the south, fault traces are found in Carcar City, Sibonga, Argao, Moalboal, Badian, Dalaguete, Alegria and Alcoy.
“Although these towns are mentioned, it does not mean that the other towns need not prepare,” he said. “Ang kailangan lang naman diyan is iwasang magtayo directly on top of the fault.”
Considering that Cebu has not yet experienced a “big one,” Solidum said that it is important that everyone should be prepared in case these faults would move and generate a major earthquake in the area.
“I think the message should be okay. There are faults in the area and these would move; we need to be prepared. Hindi mo kailangan katakutan ang fault,” he said.
“Kailangan lang malaman. Ayoko lang na ang dating na magbanggit tayo ng fault, matakot yung tao. Hindi dapat ganon. Iiwasan lang at kapag nagtayo ng matibay na bahay at building, okay na, hindi masisira,” he said.
Despite the several minor earthquakes experienced in Cebu about a week ago, Solidum explained that these small events should not be taken as a sign that a “big one” is about to hit.
“The earthquakes in Asturias are part of the earthquake swarm offshore, dun sa dagat,” he said. “So these are small events, nothing to worry. You cannot use the small events that there will be a big one. There’s no trend.”