Mild earthquakes shook the provinces of Surigao del Sur, Agusan del Sur, Ilocos Norte, Davao Occidental on Monday, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
In its bulletin, Phivolcs said the first quake with a magnitude of 3.4 occurred at 3:50 a.m.
The epicenter of the quake was traced some 18 kilometers northeast of Cortes in Surigao del Sur.
The quake, which was tectonic in origin, had a depth of one kilometer.
The second quake with a magnitude 3.4 occurred around 5:01 a.m. with epicenter traced some 15 kilometers southwest of San Luis, Agusan del Sur.
The quake, which was tectonic in origin, had a depth of 85 kilometers.
On the other hand, the third tremor with a magnitude of 3.2 occurred at 6:56 a.m. Phivolcs said its epicenter was estimated six kilometers southeast of Pinili, Ilocos Norte.
Phivolcs said the temblor, which was tectonic in origin, had a shallow depth of 26 kilometers.
Three hours later, a fourth tremor with a magnitude of 3.3 was recorded in Davao Occidental around 9:09 a.m., and its epicenter was located at 16 kilometers southeast of Jose Abad Santos and had a depth of 179 kilometers.
Meanwhile, Phivolcs said there was no casualty or damage reported from the four tremors.
It added that no aftershocks are expected as well.
The Philippines lies on the Pacific Ring of Fire, where 20 to 25 earthquakes per day — mostly imperceptible — are common, Phivolcs said.