Vatnafjöll
Seismicity by period · derived statistics from Skjálftalísa (Icelandic Met Office)
Status (automatic)
No particular signs of unrest in the last 24 hours — 0 earthquakes recorded, within the system's normal range.Fissure system south of Hekla, often regarded as part of the Hekla system. Last erupted ~1200 years ago. (overview — more at vedur.is) · circle on the map = rough outline of the system (radius).
📜 Did you know?
Vatnafjöll is an approximately 40 km long fissure swarm just south and east of Hekla that erupts only basalt, in contrast to its neighbour Hekla, which produces more evolved magma (basaltic andesite and even silicic tephra). Although more than two dozen eruptions have occurred at Vatnafjöll during the Holocene (the last ~11,500 years), the system has not erupted for about 1,100 years and is largely overshadowed by the highly active Hekla. The largest earthquake in south Iceland since 1912, the Vatnafjöll earthquake of 25 May 1987 (Mw 5.9), occurred at the southern end of the ridge where the South Iceland Seismic Zone meets the Eastern Volcanic Zone.
Points = earthquake locations in the selected window, coloured by magnitude: M3+ · M2+ · smaller (a sample if more than 800).
Earthquakes
0
Largest
–
M3,0+
0
Depth range
–
Earthquakes over time
Cumulative count · 0 earthquakes · count moment
Depth (0 km at top).
Not enough depth data.
Magnitude distribution
Earthquakes
3
Largest
M0.9
M3,0+
0
Depth range
6–16 km
Earthquakes over time
Cumulative count · 3 earthquakes · total moment ≈ M1.0 · count moment
Depth (0 km at top).
Magnitude distribution
Depth cross-sections — color by age (orange=newest, grey=older), point size by M. Rising cluster = possible magma intrusion.
Earthquakes
6
Largest
M0.9
M3,0+
0
Depth range
5–16 km
Earthquakes over time
Cumulative count · 6 earthquakes · total moment ≈ M1.1 · count moment
Depth (0 km at top). Grey: fixed depth.
Magnitude distribution
Depth cross-sections — color by age (orange=newest, grey=older), point size by M. Rising cluster = possible magma intrusion.
Earthquakes
8
Largest
M1.0
M3,0+
0
Depth range
5–16 km
Earthquakes over time
Cumulative count · 8 earthquakes · total moment ≈ M1.2 · count moment
Depth (0 km at top). Grey: fixed depth.
Magnitude distribution
Depth cross-sections — color by age (orange=newest, grey=older), point size by M. Rising cluster = possible magma intrusion.
Earthquakes
55
Largest
M3.2
M3,0+
1
Depth range
0–16 km
Earthquakes over time
Cumulative count · 55 earthquakes · total moment ≈ M3.2 · count moment
Depth (0 km at top). Grey: fixed depth.
Magnitude distribution
Depth cross-sections — color by age (orange=newest, grey=older), point size by M. Rising cluster = possible magma intrusion.
Note: before February 2026 about half of events lacked an automatic magnitude, so magnitude-dependent figures (b-value, count of M≥X) under-count earlier periods — the catalogue is not homogeneous across this window. Cumulative moment is barely affected.
Earthquakes
101
Largest
M3.2
M3,0+
1
Depth range
0–16 km
Earthquakes over time
Cumulative count · 101 earthquakes · total moment ≈ M3.2 · count moment
Depth (0 km at top) — shallowing in the data (7.6→6.0 km). Grey: fixed depth.
Magnitude distribution
Depth cross-sections — color by age (orange=newest, grey=older), point size by M. Rising cluster = possible magma intrusion.
Note: before February 2026 about half of events lacked an automatic magnitude, so magnitude-dependent figures (b-value, count of M≥X) under-count earlier periods — the catalogue is not homogeneous across this window. Cumulative moment is barely affected.
Depth is automatic and uncertain; earthquakes alone do not show magma movement — deformation (GPS) and gas are needed. Grey points: automatic fixed-depth values. b-value computed for M≥1.5 (automatic magnitudes make lower completeness unreliable). Preliminary data.
Earthquakes in the system
| Time (UTC) | Mag | Depth (km) | Area |
|---|---|---|---|
| 2026-07-25 05:47 | M0.9 | 16.1 | Hekla |
| 2026-07-25 04:58 | M0.5 | 13.1 | Other areas |
| 2026-07-25 00:56 | M0.1 | 6.5 | Other areas |
| 2026-07-23 07:55 | M-0.2 | 5.2 | Other areas |
| 2026-07-23 07:52 | M0.0 | 5.3 | Other areas |
| 2026-07-22 17:28 | M0.5 | 5.7 | Other areas |
| 2026-07-15 12:10 | M1.0 | 4.8 | Hekla |
| 2026-07-12 09:10 | M-0.2 | 6.6 | Other areas |
| 2026-06-25 04:42 | M-0.4 | 8.9 | Other areas |
| 2026-06-22 01:49 | M1.5 | 0.0 | Other areas |
| 2026-06-18 18:27 | M0.3 | 0.1 | Other areas |
| 2026-06-07 23:01 | M0.9 | 10.1 | Hekla |
| 2026-05-05 19:01 | M0.0 | 4.5 | Other areas |
| 2026-04-05 02:47 | M0.9 | 9.1 | Other areas |
| 2026-03-24 03:12 | M0.4 | 8.1 | Other areas |
| 2026-03-20 20:33 | M0.5 | 7.8 | Other areas |
| 2026-02-03 13:33 | M0.5 | 8.4 | Other areas |
| 2026-01-25 18:20 | – | 8.6 | Other areas |
| 2025-12-29 23:53 | M-0.1 | 8.9 | Other areas |
| 2025-12-14 03:15 | – | 9.3 | Hekla |
| 2025-12-08 02:34 | – | 2.4 | Other areas |
| 2025-11-14 06:55 | – | 4.3 | Other areas |
| 2025-11-08 05:13 | M0.1 | 5.5 | Hekla |
| 2025-10-29 23:45 | – | 6.3 | Other areas |
| 2025-10-28 05:00 | – | 4.0 | Hekla |
| 2025-10-21 12:34 | – | 8.6 | Hekla |
| 2025-10-15 18:57 | – | 6.3 | Other areas |
| 2025-10-13 06:50 | M0.0 | 7.4 | Hekla |
| 2025-10-03 20:25 | – | 7.8 | Hekla |
| 2025-10-01 10:55 | M0.9 | 5.7 | Hekla |
| 2025-10-01 10:55 | – | 5.9 | Hekla |
| 2025-09-22 08:31 | – | 9.3 | Other areas |
| 2025-09-21 22:47 | – | 5.6 | Hekla |
| 2025-09-16 17:43 | – | 6.8 | Hekla |
| 2025-09-16 13:31 | M-0.7 | 2.8 | Hekla |
| 2025-09-11 04:46 | – | 5.5 | Hekla |
| 2025-09-09 08:46 | – | 6.3 | Other areas |
| 2025-09-08 16:52 | – | 5.7 | Hekla |
| 2025-09-08 14:30 | – | 5.6 | Hekla |
| 2025-09-08 13:59 | – | 6.3 | Hekla |
| 2025-09-08 13:59 | M3.2 | 5.3 | Hekla |
| 2025-09-05 07:46 | – | 6.0 | Hekla |
| 2025-09-05 07:14 | M1.3 | 5.8 | Hekla |
| 2025-09-04 18:43 | M0.7 | 6.3 | Hekla |
| 2025-09-04 18:41 | – | 6.6 | Hekla |
| 2025-08-31 08:21 | M-0.1 | 8.3 | Other areas |
| 2025-08-29 21:39 | – | 6.0 | Hekla |
| 2025-08-21 20:22 | M0.7 | 4.1 | Hekla |
| 2025-08-21 20:09 | M0.8 | 4.0 | Hekla |
| 2025-08-13 17:32 | – | 5.2 | Hekla |
| 2025-08-12 21:19 | M-0.4 | 5.8 | Hekla |
| 2025-08-12 18:05 | – | 5.5 | Hekla |
| 2025-08-04 01:53 | – | 8.0 | Hekla |
| 2025-08-04 01:10 | – | 4.5 | Hekla |
| 2025-08-01 21:27 | M0.5 | 5.9 | Hekla |
| 2025-07-10 07:10 | – | 10.1 | Other areas |
| 2025-07-05 12:06 | – | 1.1 | Other areas |
| 2025-07-02 04:27 | – | 3.3 | Hekla |
| 2025-06-04 01:49 | – | 7.0 | Other areas |
| 2025-05-07 15:34 | M1.3 | 8.4 | Other areas |
What do the numbers mean — and what should I do?
β (swarm signal): how high activity is versus the area's 2-year average. β above 2 means an ongoing swarm. It measures activity, not a forecast of a large quake.
Cumulative moment (Mw): the combined energy of the quakes in the period. Uplift (GNSS): whether the ground is rising or sinking, mm per year — the data are a few weeks old. Some systems (e.g. Svartsengi) deform in steps during eruption cycles rather than at a steady annual rate.
Swarm character is computed for a whole volcanic belt, not a single system — it describes the belt, not necessarily this one system.
What should I do? This is automatic monitoring for information — not an official warning. Follow official information from the Icelandic Met Office and Civil Protection (112).