Seismic Swarm VS20260115.1 Near Volcano, Hawaii
Seismic swarm VS20260115.1 began at 07:32 on 14 January 2026 and concluded at 10:57 on 21 January 2026. Located 6 km southwest of Volcano on Hawaii’s Big Island, the sequence lasted 171 hours and 25 minutes, registering 84 earthquakes. Magnitudes ranged from 0.7 to 3.1, with the majority between 1.4 and 1.9. Most events occurred at depths of 0–8 km, consistent with shallow crustal processes, while a subset of later events reached 27–48 km.
Activity initiated with two events at 07:32 on 14 January, followed by scattered shallow shocks throughout the day. A notable cluster developed on 15 January between 05:10 and 06:27, producing 18 events, nearly all at depths of 1–3 km. Subsequent days showed continued low-magnitude shallow seismicity, punctuated by isolated deeper events. On 19–21 January, several earthquakes at 27–48 km depth appeared, including a magnitude 3.1 event at 29 km on 20 January. These deeper signals may reflect separate stress adjustments beneath the volcanic edifice.
The swarm area lies on the south flank of Kīlauea volcano, part of the Hawaiian hotspot chain. Kīlauea remains one of Earth’s most active volcanoes, built by repeated shield eruptions fed by a mantle plume. Its southeast flank experiences persistent seaward motion along a décollement at approximately 8–10 km depth, generating frequent microseismicity. Magma transport through rift zones and shallow reservoirs commonly triggers earthquake swarms lasting hours to weeks.
Historical records since 2000 document 127 swarms in the same region. Annual counts varied, with notable increases in 2020 (14 swarms), 2021 (11), 2023 (22), and 2024 (17). These episodes typically coincide with magma intrusion or pressurization beneath the summit or upper east rift zone. The 2018 lower Puna eruption, for example, was preceded and accompanied by intense swarms lasting weeks.
The January 2026 sequence fits established patterns of Kīlauea unrest. Predominantly shallow depths align with brittle failure above the shallow magma system, while the deeper events may indicate minor adjustments within the volcanic pile or upper mantle. No surface deformation or eruptive activity has been linked to this swarm in available monitoring summaries.
- USGS Hawaiian Volcano Observatory reports on Kīlauea seismicity and structure
- Global Volcanism Program database entries for Kīlauea activity since 2000
- Peer-reviewed studies on Hawaiian flank tectonics and magma-induced swarms (e.g., Journal of Geophysical Research)