A magnitude 7.1 earthquake jolted Davao Oriental at 1:46 a.m. Thursday.
The Philippine Institute of Volcanology and Seismology said the quake’s epicenter was located 75 kilometers east of Governor Generoso, Davao Oriental. Of tectonic origin, the tremor was at a depth of 39 kilometers.
In Luzon, the Taal Volcano Network recorded at least 141 volcanic earthquakes, including 121 volcanic tremor events, in Taal Volcano, Batangas. Two strong volcanic tremor events were recorded at 4:36 a.m. and 6:53 a.m. at ML 2.6 and ML 4.1, respectively, and felt at Intensity 2.
According to Phivolcs director Renato Solidum Jr., there was no damage reported after the earthquake in Mindanao.
Intensity 5 was felt in Davao Oriental’s Governor Generoso, City of Mati, Baganga and Lupon; Davao del Norte’s Tagum City, Panabo City, Carmen and Nabunturan; and Sarangani’s General Santos City, Alabel and Malungon.
Davao City; Davao del Sur’s Kiblawan; South Cotabato’s Koronadal City, Tampakan, Tupi and Polomolok; Sarangani’s Glan, Malapatan and Kiamba, and Davao de Oro’s Monkayo experienced intensity 4.
Intensity 3 was felt over Cotabato’s Kabacan, and Agusan del Sur’s Bayugan, while Cagayan de Oro City; Sarangani’s Maasim; and Cotabato’s Arakan and Banisilan had intensity 2.
On the other hand, activity at Taal’s main crater was dominated by upwelling of hot volcanic fluids in its lake which generated plumes 1,500 meters tall that drifted to the northeast and southwest.
Sulfur dioxide emission averaged 3,004 tons per day as of Wednesday.
Alert level 2 (increased unrest) now prevails over Taal Volcano.
“The Department of Science and Technology-Phivolcs reminds the public that at alert level 2, sudden steam- or gas-driven explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within and around Taal Volcano Island,” Phivolcs said.
Meanwhile, Mount Pinatubo’s alert level status is now at Level 0 (normal), after five months from being under alert Level 1 (low-level unrest).
Phivolcs said observational parameters have returned to baseline levels and the volcano has returned to a period of quiescence.
Earthquake activity has been declining since July 1, with a total of 104 volcanic quakes or an average of 2 to 3 quakes per day until August 11.
“This is a significant decrease compared to the period from January 28 to June 30 when earthquake activity averaged 12-13 events a day,” Phivolcs said.