Masbate Earthquake
[Report made by Jheiney Gwyneth Manalo]
Date and location of the disaster
18 August 2020: A magnitude 6.6 earthquake shook the province of Masbate and its vicinity at 8:03 AM. The earthquake's epicenter is located 7 kilometers southwest of Cataingan, Masbate, and has a depth of 21 kilometers.
19 August 2020: As of 4:00 PM, 244 aftershocks ranging from magnitude 1.6 to magnitude 5.1 were recorded. 129 of which were plotted, and five were felt.
Nature of the disaster
The disaster in Masbate recorded a magnitude of 6.6 which is classified as a major earthquake that may cause a lot of damage in vulnerable areas. The earthquake was felt with a maximum ground shaking intensity of PEIS VII (Destructive) at Cantaingan, Masbate. According to the Philippine Institute of Volcanology and Seismology,
"At PEIS VII, most people get frightened and run outdoors. People find it difficult to stand on the upper floors. Heavy objects and furniture overturn or topple. Trees are shaken strongly. Big church bells may ring. Old or poorly-built structures suffer considerable damage. Some well-built structures are slightly damaged. Some cracks may appear on dikes, fish ponds, road surfaces, or concrete hollow block walls. Liquefaction effects (e.g. subsidence, sand boils, lateral spreads, etc.) in low-lying areas and landslides in mountains are observed near the epicenter."
Natural or man-made?
An earthquake is a natural disaster that resulted from a natural phenomenon on the Earth's surface.
What type of hazard?
It is a geologic hazard because it originated from the crust and resulted to other hazards in connection to Earth's surface such as tremors, ground ruptures, and liquefaction.
Vulnerability and exposure level of the community
PHIVOLCS stated that Masbate is one of the country's seismically active places because of the presence of active faults that include the Masbate segment of the Philippine Fault, and potentially active faults that include Uson Fault and the Southern Masbate Fault. Prior to the 2020 earthquake, the province has experienced at least 11 earthquakes with magnitudes from 6.0 to 7.0 between 1869 and 2003. Fortunately, it is not vulnerable to earthquake-induced volcanic eruptions nor tsunami.
Disaster Mitigation Techniques
Since an earthquake cannot be prevented or detected early, no pre-emptive evacuation was possible.
NDRRMOC and DOST-PHIVOLCS immediately disseminated earthquake information nos. 1 and 2, and Tsunami information no. 1 through Short Messaging System (SMS), website, and Twitter accounts.
NDRRMOC prepared emergency alerts and warning messages for dissemination of Telecommunications Companies to the affected areas.
These two agencies worked together in the continuous monitoring of development of earthquake activities and aftershocks.
DSWD Central Office, Field Offices and National Resource Operations Center distributed a total of 292,941 family food packs, other food items and non-food items.
DPWH provided warning signages and post-earthquake assessments on roads and bridges.
Southern Luzon Command, AFP provided one aircraft for the conduct of Rapid Damage and Needs Assessment.
DepEd also assisted in doing field situation reports on infrastructure and non-infrastructure damages. The agency also continuously sent advisories and reports to the affected regions.
Local government units and regional agencies also assisted and provided financial, food, and material aids to the affected people.
Damages, Injuries, and Casualties
According to the latest report of the government, 58 barangays with a total of 1,524 families / 6,474 individuals were affected by the earthquake. 327 of the families stayed in 15 evacuation centers while 10 families stayed with their relatives. There were 50 injured persons and one dead.
The Office of Civil Defense in Bicol said that the earthquake destroyed P309 million worth of infrastructure.
A total of 1,305 houses and 86 schools were damaged. Other infrastructures that suffered from the earthquake include a district hospital, public market, and other offices. Six road sections and seven bridges in Masbate and Camarines Sur were also damaged but declared passable on August 18, 2020.
An aerial survey by the OCD and the Philippine Air Force showed a sea sinkhole in Barangay Kasabangan, Pio V. Corpus, as well as liquefaction (soil loses its strength and stiffness due to shaking) in Barangay Matayum, Caitangan. There was also a landslide reported in Pio V. Corpus.
To know more about the earthquake, click the link below to view the situational reports of NDRRMC.
References:
Barcia, R. (2020, August 26). Masbate earthquake infra damage balloons to P309 million. RAPPLER. https://www.rappler.com/nation/infrastructure-damage-earthquake-masbate-august-2020/
DOST-PHIVOLCS (2020, August 19). PRIMER ON THE 18 AUGUST 2020 MAGNITUDE (MW) 6.6 MASBATE EARTHQUAKE. Department of Science and Technology Philippine Institute of Volcanology and Seismology. https://drive.google.com/drive/folders/1RXw068AeuGiYFzIC1GZxdSYIUNkVM9e1