Magnitude 4.9 aftershock jolts Davao Occidental — Phivolcs

MANILA, Philippines — A magnitude 4.9 quake occurred in Balut Island in Sarangani, Davao Occidental at around 5:34 a.m on Wednesday, July 1, according to the country’s earthquake monitoring agency.

The Philippine Institute of Volcanology and Seismology (Phivolcs) said the recorded earthquake was an aftershock of the magnitude 7.8 and magnitude 6.5 earthquakes that struck offshore Sarangani and offshore Davao Occidental respectively on June 8.

The following reported intensities were felt in the following areas:

• Intensity IV (moderately strong) - Kiamba, Sarangani.
• Intensity I (scarcely perceptible) - General Santos City

Instrumental facilities, meanwhile, were recorded in these areas:

• Intensity III (weak) - Kiamba and Maasim, Sarangani
• Intensity II (slightly felt) - Santa Maria, Davao Occidental; Malapatan, Malungon and Maitum, Sarangani; T’Boli, South Cotabato; and Palimbang, Sultan Kudarat
• Intensity I (scarcely perceptible) - Digos City, Davao del Sur; Koronadal City, Surallah and Santo Niño, South Cotabato. 

Reported intensities are earthquake intensities assessed subjectively based on human observation and structural damages, while instrumental intensities are measured objectively using seismological instruments.

Intensity refers to the strength of the ground shaking, while magnitude is the amount of energy and size of the earthquake.