A magnitude 4.1 earthquake hits Masbate City at 6:21 a.m. on Sunday, September 24, 2023, Phivolcs says. (Photo courtesy of Phivolcs)
This story is updated to reflect the revised information on the magnitude and depth of focus of the earthquake as supplied by Phivolcs.
MANILA, Philippines — A magnitude 4.7 earthquake shook Masbate City on Sunday morning, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
The tectonic quake occurred at 6:21 a.m. with a depth of focus of 11 kilometers, it added.
Phivolcs said it recorded various instrumental intensities in different areas:
- Intensity IV – City of Masbate, Masbate
- Intensity III – Batuan and Milagros, Masbate
- Intensity II – Aroroy, Masbate; Rosario, Northern Samar; Bulusan, Sorsogon; City of Legazpi, Albay
- Intensity I – Cataingan, Masbate, Kawayan, Biliran
It likewise said that reported intensities were felt in the following areas:
- Intensity IV – City of Masbate and San Fernando, Masbate
- Intensity III – Batuan, Milagros, Mobo, and Monreal, Masbate
- Intensity II – Aroroy, Baleno and San Pascual, Masbate; Allen, San Isidro,
and Victoria, Northern Samar; City of Calbayog, Samar - Intensity I – Palanas and Mandaon, Masbate
Phivolcs warned the public against possible aftershocks.
According to Phivolcs Science Research Analyst Lara Guianan, reported intensity is the strength of an earthquake as felt and reported by people while instrumental intensity is measured by an intensity meter or scale.
“‘Yung reported intensities ayun po ‘yung naramdaman base sa pagrereport ng mga tao and then ‘yung instrumental intensity is based sa intensity meter instrument,” she said in a phone interview with INQUIRER.net.
(The reported intensities are what people felt based on reports and then the instrumental intensity is based on the intensity meter instrument.)
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