Magnitude 4.6 earthquake off the coast of the Philippines: impact on submarine cables
What Happened
At 17:21 local time on May 30, 2026, an earthquake with a magnitude of 4.6 occurred off the coast of the Philippines, approximately 63 km west of the city of Catuday.
Cables in Zone
Several key submarine cables are located within a radius of 500 km from the epicenter:
- Southeast Asia-Japan Cable (SJC) (8900.0 km, RFS 2013, China Mobile, China Telecom) — at a distance of 296.7 km from the epicenter.
- Asia Link Cable (ALC) (7200.0 km, RFS 2027, China Telecom, China Unicom) — at a distance of 121.8 km from the epicenter.
- Asia-America Gateway (AAG) Cable System (20000.0 km, RFS 2009, AT&T, BT) — at a distance of 126.5 km from the epicenter.
- Asia United Gateway East (AUG East) (8900.0 km, RFS 2029, Amazon Web Services, Arteria) — at a distance of 130.4 km from the epicenter.
- Candle (8000.0 km, RFS 2028, IPS, Inc.) — at a distance of 259.4 km from the epicenter.
- Apricot (11972.0 km, RFS 2025, Chunghwa Telecom, Google) — at a distance of 259.4 km from the epicenter.
- PLDT Domestic Fiber Optic Network (DFON) (11100.0 km, RFS 1997, PLDT) — at a distance of 296.7 km from the epicenter.
- TPU (13470.0 km, RFS 2026, Google) — at a distance of 315.9 km from the epicenter.
What our measurements show
Our monitoring shows anomalies on several cables. On the Southeast Asia-Japan Cable (SJC), significant changes in RTT were recorded: Baseline RTT was 79.1 ms, and after the earthquake, the value increased to 120.4 ms (+41.3 ms, 7.8σ from the baseline level).
Context and Risks
The earthquake may disrupt connectivity in the region, affecting global internet traffic. Issues with such key cables can cause delays and disruptions in traffic.
Further Monitoring
We will continue to monitor all cables to timely identify any changes. Special attention will be paid to the Southeast Asia-Japan Cable (SJC), where anomalies have already been recorded.
