Events, past 24h
1,842
+710% vs median
The mountain has been awake since Tuesday.
Vent Four is the public monitoring feed for the Kaldbrún fissure system. Everything on this page comes off the same instruments the response team uses, at the same time they get it, with nothing removed.
VF-04 — vertical component
last 60 minutes · 100 Hz · counts
Current readings
Compared against the fourteen-day median. Anything in red is outside the range this system has held since 2019.
Sulphur dioxide
9,400 t/d
+1,100% vs median
Ground uplift
31 mm
since Tuesday 04:00
Tremor amplitude
sustained
continuous since 19:40
Event log
Located events above M2.0. Depths are below sea level; the fissure floor sits at 640 metres.
Today 03:51:22M4.12.1 km depth, 400 m north of the 2021 crater. Felt in Hvalstaðir.
Today 03:12:08M3.31.8 km depth. Part of a swarm of 96 events in eleven minutes.
Today 01:44:57M2.93.4 km depth, migrating south-east at roughly 200 m/hour.
Yesterday 23:19:41M4.61.4 km depth. Largest of the sequence. Rockfall reported on the eastern rim.
Yesterday 19:40:12—Onset of continuous volcanic tremor. Has not stopped since.
Yesterday 16:02:33M3.04.9 km depth. First event of the current sequence.
What this means
Magma is moving upward through a crack about two kilometres under the eastern rim. It has been doing this since Tuesday evening and it has not slowed down.
An eruption at Kaldbrún would most likely open as a fissure along the existing line, not as a single crater. The modelled flow paths reach the ring road in nine to fourteen hours and do not reach any occupied building.
The road is closed. The hiking routes north of the pass are closed. Nobody is being evacuated, and nobody has been asked to prepare to be.
If that changes you will hear it from the civil protection service and from the sirens, not from this page. This page is a window, not a warning.
It is the most beautiful thing any of us will ever be paid to watch closely.
Data
Continuous waveform, GNSS baselines, gas flux and thermal are all open. No key, no rate limit, no attribution required. Cite us if it is useful to you.