The swarm is strongly felt in Kidapawan City, Makilala, and Magpet – areas located at the foot of Mount Apo, the country’s highest peak.
Since 7 p.m., Thursday, the Phivolcs has recorded 48 earthquakes. Two movements were considered strong and recorded at intensity 5 in Richter scale, one was monitored at intensity 4, and the rest were relatively weak.
Daquipa said they monitored the epicenter of the earthquake swarm at Malasila Valley fault which is connected to the Mindanao fault.
The quakes resulted in a land crack in Barangay Malasila, which was measured at about 30 meters deep, according to Daquipa.
The movements sent residents in the area in a panic.
“Nagproblema gyud kami kay naghirig among balay tungod sa linog. Sa gawas na lang mi natulog (We were so worried because our house was shaking because of the earthquakes. We slept outside our house),” said Amy, a resident of Barangay Rodero in Makilala.
Residents blamed the drilling operations of the Philippine National Oil Company (PNOC) in Mount Apo as the “culprit,” but which Phivolvcs dismissed as “baseless.”
But Daquipa said if there were, indeed, drilling operations, the movements could only be felt in areas near the site.
“That means, only those residents living in areas at least 10-kilometer radius of the site, could feel the quakes. But that was not the case here. The movements were felt as far as Cagayan de Oro City,” Daquipa explained.
The PNOC drilling operations were temporarily stopped after the provincial board of North Cotabato filed charges of violation of the agreement against the company. The court issued a temporary restraining order against the PNOC as it was discovered that the latest PNOC drilling operations were outside the 701-hectare in Mount Apo that government approved for geothermal exploration.
“So, since last year, there was no drilling operation. Why blame it?” Daquipa asked.
The Manila Times in a report on August 22, 2007 said Phivolcs was monitoring a cluster of earthquakes, called “swarming” southeast of Malasila and Balatukan in Kidapawan City. “Swarming in these areas has occurred since Friday. About 8 a.m. Tuesday.
a total of 53 events in the area were tallied with 3.1 as highest magnitude,” the report said.
The Times quoted Ishmael Narag, Phivolcs Seismology Division officer in charge, as saying that Phivolcs was closely monitoring the swarming “due to its proximity to Mount Apo, besides the area being heavily polluted.” (MindaNews)