M4.7 Earthquake 64 km ESE of San Ignacio, Philippines — November 20, 2021
2021-11-20 14:35:46 UTC (2021-11-20) · approx. 10:35 PM UTC+8 local
Aftershock of the M5.0 mainshock.
On November 20, 2021 at 14:35 UTC, a magnitude 4.7 shallow crustal earthquake struck 64 km ESE of San Ignacio, Philippines, at a depth of 53.7 km and coordinates 6.8914°, 127.0210°.
Physical scale: An earthquake of magnitude 4.7 releases seismic energy equivalent to roughly 169 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.1 km — a useful intuition for the size of the slip patch on the fault.
This earthquake is part of an ongoing aftershock sequence following the magnitude 5.0 mainshock that occurred 27 days ago 44 km SE of Lukatan, Philippines. Since the mainshock, the USGS has recorded 1 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
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
Earthquake Details
127.0210°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.7 earthquake near San Ignacio, Philippines?
The magnitude 4.7 earthquake that struck 64 km ESE of San Ignacio, Philippines on November 20, 2021 at 14:35 UTC had a depth of 53.7 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 6.8914°, 127.0210°, which is 64 km ESE of San Ignacio, Philippines. View all earthquakes in Philippines.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.7 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.0 one earlier?
No. This magnitude 4.7 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier 44 km SE of Lukatan, Philippines. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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 4.7 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us7000fvrz). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, November 20, 2021). M4.7 Earthquake 64 km ESE of San Ignacio, Philippines — November 20, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000fvrz/