ASIDE from ground shaking due to the continued aftershocks, state seismologists on Friday warned of possible landslides as well as falling rocks that may happen especially on hilly areas following Thursday's 6.0-magnitude earthquake that shook Masbate.Based on a primer released by the Philippine Institute of Volcanology and Seismology (Phivolcs) specifically for the Masbate tremor, areas adjacent to active river channels and coasts may be vulnerable to flooding from seawater due to the combination of liquefaction-induced sinking and the change in sea level.But Phivolcs said the latest Masbate earthquake with its epicenter in Batuan town would not trigger a destructive tsunami.It said that although its epicenter was offshore, no destructive tsunami waves were generated because there was no significant vertical displacement of the sea floor.Tsunamis are often produced by earthquakes generated by active trenches and offshore faults, or faults with significant vertical movements or mass movement related to earthquake-induced landslides near bodies of water, the primer explained.

Phivolcs chief Teresito 'Toto' Bacolcol said, however, that affected communities should prepare for aftershocks.In case of another strongly felt earthquake, it is recommended that people protect themselves by doing the 'drop, cover, and hold,' he said.In homes and offices, heavy furniture and appliances should be strapped to the walls, and hanging objects securely fastened to prevent these from causing injuries, the Phivolcs head said.'People should be cautious of structures visibly weakened or having signs of damage caused by the magnitude 6.0 earthquake event as these may further be damaged by succeeding earthquakes and injure building occupants,' Bacolcol said.Structurally compromised buildings should not be reoccupied unless certified safe by structural engineers, Phivolcs said.Phivolcs has observed that during earthquake events, rumors that may cause panic are easily spread.'Please avoid sharing messages from unconfirmed and unreliable sources, and only rely on information from Phivolcs and Disaster Risk Reduction and Management Offices under the local government units,' Bacolcol advised.Using the Phivolcs' Earthquake Intensity Scale (PEIS), the highest reported intensity was Intensity 7, which meant it was destructive.At Intensity 7, most people get frightened and run outdoors and they find it difficult to stand on the upper floors. Trees are shaken strongly while big church bells may ring and old or poorly-built structures suffer considerable damage, Phivolcs said.Moreover, heavy objects and furniture may overturn or topple and some well-built structures could be slightly damaged. Some cracks may appear on dikes, fish ponds, road surfaces, or concrete hollow block walls.At least 12 earthquakes with magnitudes ranging from 6.0 to 7.0 affected the province and vicinity between 1869 and 2022. This is based on the Southeast Asia Association of Seismology and Earthquake Engineering report and Phivolcs Earthquake Catalog.The last strong earthquake in the province had a magnitude of 6.6, and it happened on Aug. 18, 2020.Earthquakes occur in Masbate because it is one of the seismically active regions in the country. It also has active faults that include the Masbate and Sibuyan Sea Segments of the Philippine Fault and potentially active faults that include the Uson Fault and Southern Masbate Fault, according to Phivolcs.There are other nearby local faults, some of which may be covered by recent deposits, and offshore active faults that could be sources of minor to strong earthquakes, it added. The agency said aftershocks may continue for several days to weeks, some of which may be felt.Phivolcs said minor earthquakes are categorized if they range from magnitude 3 to magnitude 3.9; light earthquakes, M4 to 4.9; moderate earthquakes, M5 to 5.9; strong earthquakes, M6 to 6.9; major earthquakes, M7 to 7.9; and great earthquakes, M8.0 and above.