Phivolcs deputy director Bart Bautista, however, assured the public that the warning level does not translate to a destructive or life-threatening tsunami.
"There might only be minor sea level changes. But we still urge those in the south to stay away from beaches," he told The STAR. This area covers the stretch of Batanes to Mindanao.
The Pacific Tsunami Warning Center said the quake struck at around 1:24 p.m. about 500 kilometers east of the Etorufu islands between northern Japan and Russia. There were no immediate reports of injuries or damage from the quake.
The center issued a tsunami watch for Hawaii and Alaska’s western Aleutian Islands, saying waves could reach the Hawaii’s shores just after midnight. The West Coast and Alaska Tsunami Warning Center said it was not immediately known if a tsunami was generated.
The United States’ Pacific Tsunami Warning Center, for its part, issued a tsunami warning in countries in the Pacific, including the Philippines, but cancelled it hours later after realizing that no tsunami threats existed.
Bautista said changes in the country’s beaches were expected to occur from 5 to 7 p.m. yesterday.
"The water level may rise from half a meter to one meter only. There’s no need for evacuation. After 7 p.m., we expect the situation (to normalize)," Bautista said.
Temblors of magnitude 7 are generally classified as major earthquakes capable of widespread, heavy damage.
Tsunami waves — generated by earthquakes — are often barely noticeable in the ocean but can rise to great heights once they arrive at shore.
A magnitude 9.1 earthquake off the coast of Indonesia on Dec. 26, 2004 caused a tsunami that killed at least 213,000 people in 11 countries.