Seismic Swarm in Western Turkey: Analysis of the November 2024 Event

A seismic swarm occurred in Western Turkey from 10:43 on 1 November 2024 to 21:38 on 2 November 2024, lasting 34 hours and 55 minutes. During this period, 40 earthquakes were recorded, with magnitudes ranging from 0.7 to 3.5 and focal depths primarily between 5 and 9 km. The sequence began with a magnitude 1.3 event and included a peak magnitude of 3.5 at 11:38 on 1 November, followed by numerous smaller aftershocks clustered around 7 km depth. Activity tapered off by the evening of 2 November, with the final event registering magnitude 1.0.

This swarm aligns with the tectonic setting of Western Turkey, where the Anatolian Plate interacts with the Eurasian and African plates along major fault systems, including the North Anatolian Fault and extensional structures in the Aegean back-arc region. The shallow depths observed are consistent with crustal deformation typical of this area, driven by north-south extension and strike-slip motion. Such swarms often reflect fluid migration or stress redistribution along pre-existing faults rather than a single mainshock-aftershock sequence.

Historical records indicate this is the fifth swarm in the region since 2000, following events in 2016 and 2020 that each produced two swarms. These earlier episodes similarly featured low-to-moderate magnitudes and short durations, underscoring a pattern of episodic, clustered seismicity without progression to larger destructive events.

The November 2024 swarm's characteristics—predominantly microseismic activity with rapid onset and decay—provide insight into ongoing tectonic processes. Most events remained below magnitude 2.0, suggesting limited energy release and low potential for significant ground shaking. Continued monitoring is essential in this high-seismicity zone to distinguish swarm behavior from foreshock sequences.

References

SeismoSight internal classification data for swarm S20241101.1.
USGS Earthquake Hazards Program regional tectonic summaries for Anatolia.
Peer-reviewed studies on Aegean extensional tectonics published in Tectonophysics (2023 updates).