THE Department of Environment and Natural Resources (DENR)-Mines and Geosciences Bureau (MGB) in Davao noted severe damage in five areas in the region brought by the three massive earthquakes that struck Mindanao last October.
DENR-Davao Regional Public Affairs Office (RPAO) chief Jayvee Agas said Tuesday, November 12, that areas in Davao that experienced landslides, tension cracks, slumps, and rocks rolling down slopes are in Bansalan, Magsaysay, Digos, Kiblawan, and Davao City.
Agas said these areas experienced ground deformations brought about by the three earthquakes with strengths of more than magnitude 6 -- a magnitude 6.3 (October 16), magnitude 6.6 (October 29) and magnitude 6.5 (October 31). The epicenters of all these quakes were located in Tulunan, North Cotabato.
According to DENR-MGB's report posted on the DENR-Davao's Facebook page on Tuesday, an approximately 250-meter length tension crack was observed in Sitio Marawer, Purok Tagumpay 2 in Barangay Kapatagan, Digos. The agency said a crack opening ranging from one inch to five inches and with a maximum vertical displacement of five inches was observed.
The agency said the damage is caused by the magnitude 6.3 earthquake that struck Mindanao last October 16. It was aggravated when the magnitude 6.6 tremor hit on October 29.
In Purok Talisay, Barangay Kiagot in Digos City, there were reported cases of rock rolling down slope. Loose cobble to boulder-sized volcanic rock fragments were also observed along the slope.
Another area in Digos, in Sitio Bandera, Barangay Balabag, also experienced series of tension cracks. A slump was also observed with a maximum vertical displacement of 30 centimeters.
Another landslide was observed approximately two kilometers northeast of the Purok Centro in Digos City. Adjacent to the landslide crown, series of tension cracks were also observed.
Several areas in Barangay Goma, Digos were also affected. In Sitio Kiola, a tension crack with a vertical displacement reaching up to 45 centimeters was noted, posing threat to the two houses that are adjacent to it.
The agency said the damage was brought by the October 31 earthquake.
Damage was also noted in some parts of Davao del Norte, the DENR-MGB reported.
The agency noted damages in surveyed schools in the province: two schools in Barangay Palma Gil, Talaingod, and Gatong Elementary School-Igang Extension in Asuncion.
The DENR-MGB said structural cracks were observed in the two schools in Barangay Palma Gil, while four classrooms in Gatong were recorded for temporary termination for further inspection.
Aside from the structural cracks on walls of a classroom in Gatong, a gap between the wall of a classroom to the floor was also noted, as well as a vertical displacement on the floor outside the classrooms in its old building.
The DENR-MGB conducted inspection on November 7 and 8, with monitoring and assessment done in close coordination with the Provincial Environment and Natural Resources Offices (Penros), Local/Municipal Disaster Risk and Reduction and Management Offices (L/MDRRMO), and Philippine Institute of Volcanology and Seismology (Phivolcs).
Agas said the DENR-MGB had already been conducting series of monitoring and assessment in some barangays of these areas prior to the recent earthquakes.
"Kini sila nga mga barangays ani areas nga naa'y damage na na-experience, dugay na pud ni sila ginamonitor (We have been monitoring these areas) and we're found out that these are landslide prone areas," Agas said.
Agas also said the DENR-MGB team recommended for immediate inspection and assessment in highly damaged infrastructure.
She said the DENR-MGB already notified local government units on the damage and cracks sighted in these areas, adding that they also recommended further assessment and for the relocation or temporary evacuation of household directly situated in the area, as it is highly susceptible to mass movement.
She said landslides will likely occur since rainfalls are expected throughout November.