About five years ago, I wrote an article for the national broadsheet Philippine Daily Inquirer about the findings of the state-run agency Philippine Institute of Volcanology and Seismology (Phivolcs) on the newly discovered cracks in the large swath of land in the coastal areas of Mati in the provinces of Davao Oriental and Surigao del Sur.
Desiderio Cabanlit, senior analyst of Phivolcs for southern Mindanao, said based on their 2010 findings, the new cracks have the potential to unleash an 8.3 magnitude quake. Now let’s distinguish what is magnitude and intensity that we so often hear from authorities. Magnitude is the amount of energy released from its source or epicenter, which commonly takes place in deep oceans with a depth of several kilometers. Magnitude produces so called intensity, which is strength of shaking produced by the earthquake at a certain location. Measurement of the Intensity varies from one area to another.
The bigger the magnitude, hence the greater the intensity of the shaking.
Cabanlit said in 1924 , an 8.3 magnitude earthquake hit off the coast of Mati City and in 1893 a 7.2 magnitude quake rattled the area of Monkayo in Compostela Valley province.
He said in these two historical events, several hundred people either died or were injured, although admitting no accurate data can be found.
“Personally, I am scared. It is scary for people. It’s possible but we don’t know when that quake will happen,” Cabanlit said.
So fast forward to October 16, 2019. A 6.6 magnitude quake rattled the Mindanao region with its epicenter traced in Tulunan town in North Cotabato province. Disaster officials confirmed the death of people and some 215 others injured in various parts of the region.
On Tuesday morning, Oct 29, another 6.6 magnitude earthquake struck also the same town of Tulunan. The quake was felt in different parts of Mindanao. Officials reported two fatalities and scores were injured ,
Chyna Nicole an elemtary school teacher of Daig in Tulunan town reported several of her students were rushed to the hospital, and some will be needing brain scans due to head injuries. She posted on her social media account the ordeal of her students and appeals for help as most of them were indigent families belonging to the b’laan ethnic group.
Whatever help you can extend to them, as most of them are poor, she told this columnist.
Anthony Allada, information officer of Magsaysay town in Davao del Sur said the recent quake is by far the strongest quake they felt.
The Oct 16 earthquake claimed the lives of three people, which caused renewed panic and concern among residents still reeling from the quake’s aftermath.
Government offices, schools as well as private companies In the affected Mindanao region were prompted to cancel work due to concerns of aftershocks and also as precautionary measures as damages to buildings were widely reported. Authorities also dispatched engineers to inspect buildings and infrastructure.
The Phivolcs officials in Manila also reiterated calls to thepublic to remain cautious and to be calm at the same time.