A MAGNITUDE 6.1 earthquake rocked Catanduanes yesterday but damage was not expected, the Philippine Institute of Volcanology and Seismology (Phivolcs) said,

The quake, which occurred at 5:19 a.m., was tectonic in origin and had a depth of 35 km.

Its epicenter was some 81 km northeast of Bagamanoc town, Phivolcs said.

Shaking was felt at Intensity IV in Virac town in Catanduanes and Intensity III in the towns of Garchitorena, Cabusao, Ragay, Gainza, Goa, and Lagonoy in Camarines Sur and in the towns of Palapag, Laoang, Pambujan, San Roque, and Mondragon in Northern Samar.

In a radio interview, Phivolcs director Teresito Bacolcol said the earthquake was “moderately strong,” noting Virac felt it at Intensity IV.

“It’s not destructive. Usually, Intensity 7 (earthquakes) are the destructive ones. We don’t expect damage but we are expecting aftershocks,” he said.

Bacolcol said aftershocks are felt several days to several weeks after the main shock.

“Aftershocks, again, are usually one degree lower than the main shock so the maximum aftershocks that we may record would be around (magnitude) 5, that’s the highest,” he said.

Bacolcol also said the earthquake did not pose any tsunami threat.

“We did not issue a tsunami warning. A magnitude (6.1) earthquake is not capable of generating tsunami,” said Bacolcol.