MGB eyes further study in quake-hit Leyte areas

TACLOBAN CITY, July 17 -- The Mines and Geosciences Bureau (MGB) regional office has recommended the immediate conduct of full Engineering Geological and Geohazard Assessment Report (EGGAR) to include rock and stability studies in heavily hit areas of the 6.5 magnitude quake in Leyte province.

In a report released on Monday, the MGB identified a big landslide in Rubas village in Jaro town in Leyte after a geohazard team assessed affected areas including several villages in Kananga town and Ormoc City.

The landslide in Rubas village, which runs along the mountain range of Mt. Amandewing, one of Leyte’s highest peak, dumped a significant volume into the river. However, water supply in the area was unaffected by the landslide. 

Cracks on a partially damaged building of the Bienvenido Celebre National High School in Uguiao village also in Jaro were only observed on non-load bearing portions of the buildings.

In Kananga, the villages of Lim-ao and Tongonan were heavily affected by landslides and that most of these areas are within the concession of Energy Development Corporation (EDC). 

The MGB geohazard team observed compressional cracks on the road going to Tongonan while numerous tension cracks were evident in Rizal village, with some cutting across houses and its surroundings.

MGB said threats of further landslide remained and that extensive tension cracks could exacerbate the problem and might cause rain-induced landslides.

With this, the MGB likewise recommended the “augmentation of more structural and engineering geologists as well as safety mining and civil engineers for the conduct of ground penetrating radar and resistivity geophysical survey to determine subsurface geohazards in the area.”

MGB further advised affected residents to have their houses assessed by authorities before returning to their homes. 

Meanwhile, the bureau seeks to acquire an after earthquake satellite image and interpretation of the towns of Jaro and Kananga and Ormoc City through the National Mapping and Resource Information Authority.

The 6.5 magnitude earthquake that jolted Leyte and nearby provinces last July 6 was generated by the movement of what Philippine Volcanology and Seismology (Phivolcs) has recently called the Leyte segment of the Philippine Fault.

According to Phivolcs, Eastern Visayas, including Leyte, is one of the seismically active areas in the country because of the Philippine Fault and the Philippine Trench, the main earthquake generators that can affect the area. Other local faults are potential causes of small to large magnitude earthquakes.(Ahlette C. Reyes/PNA)