By Mike Crismundo
Mild tectonic earthquakes jolted Surigao del Sur and Agusan del Norte provinces on Saturday, Sept. 16, 2017, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
In its bulletin, Phivolcs said a 3.1 magnitude earthquake was registered at 2:40 a.m. on Saturday (Sept. 16).
The epicenter was plotted 22 kilometers (km.) northeast of Bayabas town, Surigao del Sur province.
The tremor had a depth of 24 km, Phivolcs said.
At 6:21 a.m. on the same day (Sept. 16), a 2.6 magnitude earthquake was also recorded and its epicenter was traced only 13 km southeast of Santiago town, Agusan del Norte province.
The tremor had a depth of 15 km, it said.
On Friday (Sept. 15), a 3.1 magnitude earthquake was also registered at 7:14 a.m. and its epicenter was located 14 km northeast of Cortes town, Surigao del Sur, with a depth of 49 km, Phivolcs said.
The three tremors that struck Surigao del Sur and Agusan del Norte were all tectonic in origin and no aftershock is expected, the agency added.