Fagradalsfjall
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. Volcano is experiencing signs of elevated unrest above known background levels.
VONA = Volcano Observatory Notice for Aviation; the official Met Office colour code for aviation. Independent of Skjálfti's automatic analysis.
🕰️ Last eruption / event — 3 years ago
Litli-Hrútur (3rd Fagradalsfjall eruption) (2023-07-10). Activity shifted NW from Fagradalsfjall to the Sundhnúkur fissure system in Oct 2023.
Volcanic system in the central Reykjanes Peninsula. Erupted in 2021, 2022 and 2023 (Geldingadalir, Meradalir, Litli-Hrútur) — the first eruptions on the peninsula in ~800 years. (overview — more at vedur.is) · circle on the map = rough outline of the system (radius).
📜 Did you know?
Fagradalsfjall itself had been dormant for about 6000 years before the 2021 eruption. The Reykjanes Peninsula as a whole had been quiet for ~800 years (since the Reykjaneseldar of 1210-1240); models suggest a new 200-300 year active cycle.
Historical eruptions in the system — points colored by size, blue circle shows where we are now in time.
☁ Air quality — SO₂
Real-time SO₂ from Environment Agency (2026-09-11T19:00 UTC). Yellow > 20 µg/m³, orange > 125 (health threshold), red > 350. Nearest stations to this system; past 24h shown for the highest.
Grindavík9.0 µg/m³
Vogar4.9 µg/m³
Ásbrú (Keflavík)4.2 µg/m³
Keflavík (Vatnaveröld)3.5 µg/m³
Hafnarfjörður (Hvaleyrarholt)0.7 µg/m³
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
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
9
Largest
M-0.0
M3,0+
0
Depth range
0–12 km
Earthquakes over time
Cumulative count · 9 earthquakes · total moment ≈ M0.2 · 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
42
Largest
M-0.0
M3,0+
0
Depth range
0–12 km
Earthquakes over time
Cumulative count · 42 earthquakes · total moment ≈ M0.5 · 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
158
Largest
M0.2
M3,0+
0
Depth range
0–14 km
Earthquakes over time
Cumulative count · 158 earthquakes · total moment ≈ M0.9 · 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
314
Largest
M0.5
M3,0+
0
Depth range
0–16 km
Earthquakes over time
Cumulative count · 314 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
434
Largest
M1.8
M3,0+
0
Depth range
0–16 km
Earthquakes over time
Cumulative count · 434 earthquakes · total moment ≈ M1.8 · 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
5171
Largest
M3.4
M3,0+
4
Depth range
0–16 km
Earthquakes over time
Cumulative count · 5171 earthquakes · total moment ≈ M3.9 · 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.
Gutenberg-Richter b ≈ 1.21 ± 0.07 (i.e. likely 1.14–1.28, M≥1.7, n=222)
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
69.973
Largest
M4.8
M3.0+
399
Days with data
1.443
This is a reduced view: it is built from the daily aggregate (counts, moment, magnitude bands, depth histogram) rather than individual events. Map points, the depth scatter, cross-sections and the migration fit are therefore missing — they need each event's location and depth. Counts, total moment and the b-value are exact, not approximated.
Earthquakes over time
Cumulative count and moment
Total moment of all events in the window equals a single Mw 5.5
Magnitude distribution
<155197
1–29523
2–32141
3–4366
≥433
Gutenberg-Richter b ≈ 0.78 ± 0.01 (i.e. likely 0.77–0.79, M≥1.7, n=4161)
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
137.846
Largest
M4.9
M3.0+
1198
Days with data
2.487
This is a reduced view: it is built from the daily aggregate (counts, moment, magnitude bands, depth histogram) rather than individual events. Map points, the depth scatter, cross-sections and the migration fit are therefore missing — they need each event's location and depth. Counts, total moment and the b-value are exact, not approximated.
Earthquakes over time
Cumulative count and moment
Total moment of all events in the window equals a single Mw 5.8
Magnitude distribution
<1102092
1–224772
2–36329
3–41096
≥4102
Gutenberg-Richter b ≈ 0.78 ± 0.01 (i.e. likely 0.77–0.78, M≥1.7, n=12384)
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
143.131
Largest
M4.9
M3.0+
1227
Days with data
3.284
This is a reduced view: it is built from the daily aggregate (counts, moment, magnitude bands, depth histogram) rather than individual events. Map points, the depth scatter, cross-sections and the migration fit are therefore missing — they need each event's location and depth. Counts, total moment and the b-value are exact, not approximated.
Earthquakes over time
Cumulative count and moment
Total moment of all events in the window equals a single Mw 5.8
Magnitude distribution
<1104839
1–226810
2–36632
3–41124
≥4103
Gutenberg-Richter b ≈ 0.79 ± 0.01 (i.e. likely 0.78–0.79, M≥1.7, n=13042)
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
149.928
Largest
M4.9
M3.0+
1253
Days with data
4.095
This is a reduced view: it is built from the daily aggregate (counts, moment, magnitude bands, depth histogram) rather than individual events. Map points, the depth scatter, cross-sections and the migration fit are therefore missing — they need each event's location and depth. Counts, total moment and the b-value are exact, not approximated.
Earthquakes over time
Cumulative count and moment
Total moment of all events in the window equals a single Mw 5.8
Magnitude distribution
<1109294
1–228832
2–36913
3–41150
≥4103
Gutenberg-Richter b ≈ 0.79 ± 0.01 (i.e. likely 0.79–0.80, M≥1.7, n=13637)
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.
🌊 Volcanic tremor — The seismic tremor baseline is currently elevated and should only be compared to recent d…
IMO tremor plot (station vog). Most of the signal is weather and surf — not eruption confirmation. All stations: vedur.is ↗.
Weather now: wind 4 m/s (Fagradals-Hagafelli), waves 3.1 m — notable — likely weather.
The seismic tremor baseline is currently elevated and should only be compared to recent days since wind and wave conditions do not reliably correlate with the readings at this station. (AI)
Band analysis past 9 days (from digitized RSAM values). High 2-4 Hz + low 0.5-1 Hz = possible magma-movement signal; high 0.5-1 Hz without 2-4 Hz = weather/surf.
Earthquakes in the system
| Time (UTC) | Mag | Depth (km) | Area |
|---|---|---|---|
| 2026-09-09 00:51 | M-0.2 | 10.6 | Reykjanesskagi |
| 2026-09-06 10:00 | M-0.0 | 11.8 | Reykjanesskagi |
| 2026-09-06 09:59 | M-0.5 | 10.6 | Reykjanesskagi |
| 2026-09-06 02:27 | M-1.2 | 6.8 | Reykjanesskagi Grindavík |
| 2026-09-06 01:47 | M-0.3 | 11.8 | Reykjanesskagi |
| 2026-09-06 01:47 | M-0.7 | 10.9 | Reykjanesskagi |
| 2026-09-06 01:46 | M-1.3 | 10.9 | Reykjanesskagi |
| 2026-09-05 12:01 | M-0.6 | 0.0 | Reykjanesskagi Grindavík |
| 2026-09-04 22:26 | M-0.8 | 0.3 | Reykjanesskagi |
| 2026-09-04 19:36 | M-0.3 | 9.1 | Reykjanesskagi |
| 2026-09-02 01:33 | M-0.6 | 0.0 | Reykjanesskagi |
| 2026-09-01 22:53 | M-1.1 | 0.8 | Reykjanesskagi Grindavík |
| 2026-09-01 13:22 | M-0.4 | 9.2 | Reykjanesskagi |
| 2026-09-01 07:45 | M-1.0 | 9.9 | Reykjanesskagi Grindavík |
| 2026-08-30 19:37 | M-0.8 | 0.0 | Reykjanesskagi |
| 2026-08-30 06:39 | M-0.6 | 4.0 | Reykjanesskagi |
| 2026-08-30 05:29 | M-1.0 | 0.0 | Reykjanesskagi |
| 2026-08-29 19:19 | M-1.1 | 0.0 | Reykjanesskagi Grindavík |
| 2026-08-29 03:59 | M-0.9 | 1.5 | Reykjanesskagi |
| 2026-08-29 03:00 | M-0.7 | 0.0 | Reykjanesskagi |
| 2026-08-28 08:40 | M-0.7 | 9.3 | Reykjanesskagi |
| 2026-08-28 06:38 | M-1.0 | 2.6 | Reykjanesskagi Grindavík |
| 2026-08-28 04:20 | M-0.9 | 0.9 | Reykjanesskagi |
| 2026-08-27 00:23 | M-0.8 | 9.3 | Reykjanesskagi |
| 2026-08-25 23:18 | M-0.8 | 4.7 | Reykjanesskagi Grindavík |
| 2026-08-25 07:25 | M-0.5 | 0.0 | Reykjanesskagi Grindavík |
| 2026-08-25 02:10 | M-0.5 | 10.5 | Reykjanesskagi |
| 2026-08-23 23:01 | M-1.2 | 4.1 | Reykjanesskagi Grindavík |
| 2026-08-21 18:51 | M-0.5 | 9.8 | Reykjanesskagi |
| 2026-08-21 01:23 | M-1.0 | 0.0 | Reykjanesskagi |
| 2026-08-20 22:47 | M-1.2 | 0.0 | Reykjanesskagi Grindavík |
| 2026-08-20 20:51 | M-1.1 | 0.0 | Reykjanesskagi Grindavík |
| 2026-08-20 04:53 | M-0.3 | 2.3 | Reykjanesskagi |
| 2026-08-20 02:10 | M-0.9 | 0.0 | Reykjanesskagi |
| 2026-08-19 20:59 | M-1.3 | 5.9 | Reykjanesskagi Grindavík |
| 2026-08-19 19:06 | M-0.7 | 0.0 | Reykjanesskagi |
| 2026-08-19 18:48 | M-0.8 | 7.8 | Reykjanesskagi |
| 2026-08-19 08:42 | M-0.3 | 6.8 | Reykjanesskagi Grindavík |
| 2026-08-17 01:46 | M-0.6 | 0.3 | Reykjanesskagi Grindavík |
| 2026-08-16 04:45 | M-1.6 | 8.4 | Reykjanesskagi |
| 2026-08-15 21:34 | M-1.2 | 10.7 | Reykjanesskagi |
| 2026-08-13 13:11 | M-0.4 | 9.4 | Reykjanesskagi |
| 2026-08-10 04:20 | M-0.7 | 6.4 | Reykjanesskagi |
| 2026-08-09 00:50 | M-0.7 | 6.6 | Reykjanesskagi Grindavík |
| 2026-08-05 23:16 | M-0.6 | 3.7 | Reykjanesskagi Grindavík |
| 2026-08-05 02:50 | M-1.0 | 10.4 | Reykjanesskagi |
| 2026-08-04 09:45 | M-1.6 | 10.1 | Reykjanesskagi |
| 2026-08-04 08:40 | M-0.7 | 10.8 | Reykjanesskagi |
| 2026-08-04 07:25 | M-0.6 | 11.3 | Reykjanesskagi |
| 2026-08-04 07:25 | M-1.2 | 10.3 | Reykjanesskagi |
| 2026-08-04 05:42 | M-1.2 | 12.8 | Reykjanesskagi Grindavík |
| 2026-08-04 02:02 | M-1.1 | 10.3 | Reykjanesskagi |
| 2026-08-03 09:09 | M-1.2 | 5.6 | Reykjanesskagi Grindavík |
| 2026-08-03 08:37 | M-0.5 | 10.3 | Reykjanesskagi |
| 2026-08-03 08:36 | M-0.8 | 9.7 | Reykjanesskagi |
| 2026-08-03 08:36 | M-1.1 | 8.9 | Reykjanesskagi |
| 2026-08-03 08:35 | M-0.6 | 12.1 | Reykjanesskagi |
| 2026-08-03 08:35 | M-0.9 | 9.6 | Reykjanesskagi |
| 2026-08-03 08:27 | M-0.1 | 13.4 | Reykjanesskagi |
| 2026-08-03 08:26 | M-0.3 | 13.7 | Reykjanesskagi |
For the advanced — expert charts — Coulomb, migration, InSAR
🔬 Coulomb stress transfer — advanced analysis
4 earthquakes M≥3.0 in this window on this system. Such events transfer stress to neighbouring faults — some become more likely to slip, others less ("Coulomb stress transfer"). The Met Office does not publish focal mechanisms for automatically located events, so Skjálfti does not compute this itself — it requires strike/dip/rake data which is only available for M≥4.5 events in the GCMT catalogue.
For Coulomb analysis, see: USGS Coulomb 3.4 (stand-alone software) and focal mechanisms for Iceland in Global CMT.
For Coulomb analysis, see: USGS Coulomb 3.4 (stand-alone software) and focal mechanisms for Iceland in Global CMT.
📡 InSAR — radar deformation across the area
InSAR is satellite radar from Sentinel-1: it measures deformation across the whole area, not just points like GNSS stations. Six-day interferograms reveal where the ground rose or subsided between passes. InSAR distinguishes vertical deformation (magma chamber inflation) from horizontal (dike intrusion) — GNSS alone cannot.
View latest interferograms and time-series at COMET LiCS portal (Sentinel-1, ~4-6 day lag).
View latest interferograms and time-series at COMET LiCS portal (Sentinel-1, ~4-6 day lag).
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).