M6.6 Earthquake 13 km E of San Pedro, Philippines — August 18, 2020
2020-08-18 00:03:48 UTC (2020-08-18) · approx. 8:03 AM UTC+8 local
Felt by 128 people across surrounding communities. Maximum shaking intensity MMI 8.3 (violent).
On August 18, 2020 at 00:03 UTC, a magnitude 6.6 shallow crustal earthquake struck 13 km E of San Pedro, Philippines, at a depth of 10.0 km and coordinates 12.0257°, 124.1272°. The earthquake was reported felt by 128 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 8.3 (violent). The USGS PAGER system issued a yellow alert level for this event, indicating local impact possible. The nearest populated place is San Pedro (population 2,318).
Physical scale: An earthquake of magnitude 6.6 releases seismic energy equivalent to roughly 120 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 22 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Philippines, a region characterized by the Manila Trench and Philippine Trench subduction systems, where the Philippine Sea Plate overrides the Eurasian Plate. The nearest mapped fault system is the Philippine Fault. View all earthquakes in Philippines.
Learn more: Magnitude scale · Aftershock sequences
Nearest Populated Places
What the Shaking Felt Like
At MMI 8.3 (violent), people in the most strongly affected areas would have experienced: Severe shaking causing considerable damage. Buildings may shift off foundations. Walls crack and may partially collapse. Heavy furniture overturned.
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 128 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Population exposure (USGS PAGER)
Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.
| Shaking intensity (MMI) | Description | Population exposed |
|---|---|---|
| MMI 3 | weak | 2,125,219 |
| MMI 4 | light | 19,463,996 |
| MMI 5 | moderate | 2,069,433 |
| MMI 6 | strong | 264,083 |
| MMI 7 | very strong | 137,160 |
| MMI 8 | severe | 16,593 |
Earthquake Details
124.1272°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 6.6 earthquake near San Pedro, Philippines?
The magnitude 6.6 earthquake that struck 13 km E of San Pedro, Philippines on August 18, 2020 at 00:03 UTC had a depth of 10.0 km. It was felt by 128 people with maximum shaking intensity of MMI 8.3 (violent). For context, this was a strong earthquake capable of causing significant damage.
Where did the earthquake occur?
The earthquake epicenter was located at 12.0257°, 124.1272°, which is 13 km E of San Pedro, Philippines. The nearest populated place is San Pedro (population 2,318). View all earthquakes in Philippines.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.6 earthquakes can continue for weeks to months and gradually diminish over time.
Has Philippines had earthquakes this big before?
The largest recorded earthquake in Philippines was the M8.0 Mindanao earthquake of August 17, 1976. Today's magnitude 6.6 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us6000bgbr). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2020, August 18, 2020). M6.6 Earthquake 13 km E of San Pedro, Philippines — August 18, 2020. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000bgbr/