June was a loud month for the planet. An M7.8 offshore Mindanao triggered a tsunami warning across the southern Philippines and advisories as far as Japan; a rare, deadly doublet in Venezuela flattened neighbourhoods in seconds. Twenty-four earthquakes of magnitude 6.0 or greater were recorded worldwide. HERD was born in Phuket in memory of the 26 December 2004 tsunami — and this digest exists to keep one truth in view: in a tsunami, minutes are the difference between a warning and a wave.
Updated monthly · Compiled from official and major sources (USGS, EMSC, PHIVOLCS). Magnitudes and locations are preliminary and may be revised by the agencies.
A note on what HERD does. HERD is building a low-cost infrasound early-warning network — it listens for atmospheric pressure waves radiated by tsunamis and volcanic eruptions. It is not a seismometer network, and it did not detect or predict any of the earthquakes below. We publish this digest as context — the region is highly active, and early warning saves lives.
Two events defined the month — one because it moved the sea, one because of how it struck.
The strongest earthquake to strike the Philippines since the 1976 Moro Gulf event ruptured the Cotabato Trench offshore. PHIVOLCS issued a tsunami warning across the southern Philippines, with observed waves up to about 1.4 m; tsunami advisories reached Indonesia, Malaysia and Japan.
This is exactly the class of event HERD's mission is built around: a large offshore rupture where a coastal population has only minutes to move to higher ground.
Sources: PHIVOLCS, Philippine Daily Inquirer, GMA News, Hong Kong Observatory.
An M7.2 foreshock was followed just 39 seconds later by an M7.5 mainshock — the strongest earthquakes to hit Venezuela since 1900. Shallow strike-slip rupture caused widespread building collapse, including in Caracas, with hundreds killed.
A shallow inland strike-slip quake like this does not typically generate an ocean tsunami, but it is a stark reminder of how little warning the ground gives when a rupture is close and shallow.
Sources: USGS, Eos (AGU), CNN, AP, Britannica.
Twenty-four notable earthquakes of the month, grouped by date. Figures are preliminary and compiled from USGS and EMSC; the agencies may revise magnitudes and locations. Casualty details are given only for the two verified events above.
| Date | Mag | Location |
|---|---|---|
| 01 Jun | M6.2 | San Lucido, Italy |
| 08 Jun | M7.8 | Kablalan / Sarangani, Philippines Tsunami warning |
| 08 Jun | M6.1 | Severo-Kurilsk, Russia |
| 08 Jun | M6.0 | Pangian, Philippines |
| 08 Jun | M6.1 | Balangonan, Philippines |
| 08 Jun | M6.5 | Balangonan, Philippines |
| 08 Jun | M6.1 | Mantua, Cuba |
| 10 Jun | M6.0 | Auckland Islands, New Zealand |
| 15 Jun | M6.2 | Pondaguitan, Philippines |
| 16 Jun | M6.3 | Dunhuang, China |
| 16 Jun | M6.7 | Palu, Indonesia |
| 17 Jun | M6.6 | Mid-Atlantic Ridge |
| 19 Jun | M6.6 | Petropavlovsk-Kamchatsky, Russia |
| 19 Jun | M6.0 | Petropavlovsk-Kamchatsky, Russia |
| 24 Jun | M6.9 | Kuji, Japan |
| 24 Jun | M7.2 | San Felipe, Venezuela Foreshock |
| 24 Jun | M7.5 | Yumare, Venezuela Destructive mainshock |
| 25 Jun | M6.5 | Mindanao, Philippines |
| 25 Jun | M7.2 | Honshu, Japan |
| 26 Jun | M6.5 | Mindanao, Philippines |
| 27 Jun | M5.9 | Banda Sea |
| 27 Jun | M6.1 | Kanto, Japan |
| 27 Jun | M5.8 | Iceland |
| 27 Jun | M6.1 | Hindu Kush, Afghanistan |
Official agencies are the source of truth for these events. We defer to them for magnitudes, tsunami warnings and official guidance: USGS Earthquake Hazards Program · EMSC (European-Mediterranean Seismological Centre) · PHIVOLCS (Philippine Institute of Volcanology and Seismology). Where a national warning is involved, always follow your local official emergency channel.
HERD One and the HERD network are research instruments. They are not a certified life-safety device or a guaranteed warning system, and they do not replace official government emergency alert channels such as USGS, EMSC or PHIVOLCS. HERD did not detect or predict any of the earthquakes listed above; the network listens for infrasound from tsunamis and eruptions and does not measure seismic ground motion.
No consumer device available today can guarantee advance warning of a tsunami or volcanic eruption. In an emergency, follow the instructions of your local authorities. Full legal terms: theherd.network/terms.
HERD is an open-science effort to give coastlines those minutes. Here's how to be part of it.