BACOLOD CITY, Philippines — Sinkholes could possibly be present in at least six towns and cities in Negros Occidental, which could endanger people’s lives, according to an official of the Mines and Geosciences Bureau (MGB)-Western Visayas.
MGB-6 regional director Leo Van Juguan said that, based on the geo-hazard mapping they conducted in this province, sinkholes could be present in the hinterland areas of Kabankalan City and Cauayan town (both in southern Negros) and in Sagay City, Escalante City, Toboso and Calatrava towns (all in northern Negros).
“We are closely monitoring these areas,†Juguan said in a radio interview. However, at this time, no sinkhole was detected in the surface of the said areas, he added.
Areas with danger of occurrence of sinkholes are those that have limestone deposits, and that sinkholes usually develop underground in caves, said Juguan.
A sinkhole is a natural depression or hole in the ground caused by some form of collapse of the surface layer. Its formation involves natural processes of erosion or gradual removal of slightly soluble bedrock (such as limestone) having calcium carbonate by percolating water, collapse of a cave roof, or a lowering of the water table.
In Bacolod, Juguan said MGB-6 has not identified any area having lime stones so the occurrence of sinkholes in the city is remote. He noted that sinkholes, especially in urban areas, are dangerous especially if houses and other properties lie on its surface.
In Bohol, almost 100 sinkholes were reportedly found after the 7.2 magnitude quake last Oct. 15.