Katla (Mýrdalsjökull) 🔥 M3.3 past 24 h

Seismicity by period · derived statistics from Skjálftalísa (Icelandic Met Office)

Status (automatic)

Over the last 24 hours, 15 earthquakes were detected under Katla, a powerful central volcano beneath Mýrdalsjökull glacier, with activity remaining similar to the past week though considered slightly above normal for this area. This represents scattered background activity rather than earthquake swarms, as 86% of events over the last seven days were independent, with the largest earthquake of the last 48 hours measuring M1.7 and the cumulative magnitude reaching Mw 2.0. This activity most closely resembles the period around June 13, 2026, when 98 earthquakes were recorded, although these are automatic preliminary results where depth is unreliable. Further details and maps showing the development of the activity can be found below. (status from 2026-07-21 09:10 UTC)

VONA (Katla): Green (was: Yellow, 2024-07-29) · source

VONA = Volcano Observatory Notice for Aviation; the official Met Office colour code for aviation. Independent of Skjálfti's automatic analysis.

Depth — 3D and cross-section Katla (Mýrdalsjökull) · last 90 days

Each dot is an earthquake, depth as the third dimension — Katla (Mýrdalsjökull), last 90 days. Drag the 3D view to rotate; point at a dot for details.

3D (rotatable) · depth ×2.5

Cross-section — distance along profile (km) vs depth (km)

Map (top view)

<24 klst2–7 dolderunconstrained depthsize ∝ magnitude (M)

⚠ Preliminary depths, unreliable (automatic Met Office solutions; depth often poorly constrained). events with unconstrained (default) depth shown as open rings — not real structure. For illustration, not analysis.

🕰️ Last eruption / event — ~108 years ago

The 1918 Katla eruption (1918-10-12). Jökulhlaup over Mýrdalssand added ~4 km of coastline over several days. The current 108-year pause is among the longest in Katla's known history — it typically erupts every 40-80 years.

Powerful central volcano beneath Mýrdalsjökull, known for explosive eruptions and large glacial floods. The last major eruption was in 1918; persistent seismicity beneath the glacier. (overview — more at vedur.is) · circle on the map = rough outline of the system (radius).

Subglacial system: a subglacial eruption can cause a jökulhlaup (sudden glacial meltwater flood) with little warning, and volcanic gases (incl. SO₂, CO₂) can be dangerous near vents and may pool in hollows. These are standing features of the system, not a sign of an imminent eruption.

📜 Did you know?

The current 108-year pause is among the longest in Katla's known history (it normally erupts every 50-100 years). The Eldgjá eruption ~934 AD belongs to the Katla system — 18 km³ of lava, one of the largest lava eruptions in historical time on Earth. The 1918 eruption added about 4 km to the coast at Mýrdalssand over several days.

Historical eruptions in the system — points colored by size, blue circle shows where we are now in time.

❓ What if Katla erupts tomorrow?

Timeline: Historical warning from GPS and seismic data is 1-3 hours, but a jökulhlaup can start within a minute of subglacial eruption breach. Jökulhlaup: Most likely down Mýrdalssand (possibly down Markarfljót or Skálm). Peak flow can reach 100,000-400,000 m³/s (1918: ~300,000 m³/s; 1755: 200,000-400,000 m³/s) — comparable to the Amazon. Ring Road closes between Vík and Skógasandur for days to weeks. Ash: Wind-dependent. SW wind (common): Reykjavík spared, Suðurland worst affected. NW wind: ash reaches Faroes and Scotland. Aviation: North Atlantic flights may stop for days to weeks (cf. Eyjafjallajökull 2010). Sources: 1918 eruption added ~4 km to the Mýrdalssand coast over several days. Met Office hazard assessment (vedur.is/vatnafar/haettumat-floda).

This is not a forecast. Based on historical experience and official hazard assessments from the Met Office / Civil Protection.

Jökulhlaup history (historical renewal model + Bayesian update)

Last known flood (Múlakvísl): 2024-08-15, 710 d ago. Median interval between floods: ~3.0 yr (1111 d, n=5) · historically ~1 in 50 within 6 mo from a state like this (n=5).

Note: The Met Office does not publish open realtime water-level/conductivity data. Realtime flood monitoring requires VPN/agreement with Veðurstofa (vmkerfi.vedur.is).

AUST step detection — 6 drops ≥ 15 mm in past 2 yr (May-Oct; winter snow filtered). Each drop = ice-shell subsidence, possible jökulhlaup signal. Latest: 2025-10-11 (-17 mm).

24 h48 h7 d30 d365 d2 y

Points = earthquake locations in the selected window, coloured by magnitude: M3+ · M2+ · smaller (a sample if more than 800).

Earthquakes

Largest

M3.3

M3,0+

Depth range

0–13 km

Earthquakes over time

Cumulative count · 21 earthquakes · total moment ≈ M3.5 · 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

Largest

M3.3

M3,0+

Depth range

0–13 km

Earthquakes over time

Cumulative count · 64 earthquakes · total moment ≈ M3.5 · count moment

No significant hypocenter migration — activity is stationary (R²=0.03, n=64); no sign of a propagating dike. Migration shows automatically if R²≥0.30.

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

167

Largest

M3.3

M3,0+

Depth range

0–14 km

Earthquakes over time

Cumulative count · 167 earthquakes · total moment ≈ M3.5 · count moment

No significant hypocenter migration — activity is stationary (R²=0.00, n=167); no sign of a propagating dike. Migration shows automatically if R²≥0.30.

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

460

Largest

M3.3

M3,0+

Depth range

0–20 km

Earthquakes over time

Cumulative count · 460 earthquakes · total moment ≈ M3.6 · 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

2020

Largest

M3.3

M3,0+

Depth range

0–24 km

Earthquakes over time

Cumulative count · 2020 earthquakes · total moment ≈ M3.8 · 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.

Gutenberg-Richter b ≈ 1.03 ± 0.07 (i.e. likely 0.96–1.11, M≥1.7, n=138)

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

2791

Largest

M3.3

M3,0+

Depth range

0–24 km

Earthquakes over time

Cumulative count · 2791 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 ≈ 1.06 ± 0.06 (i.e. likely 1.00–1.12, M≥1.7, n=202)

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.

Glossary & magnitude scale →

Uplift — GNSS deformation

AUST — land subsiding ~14 mm/yr (seasonally adjusted) · long-term +37 mm/yr (MIDAS)

REYK (Reykjavík) — reference ~-2 mm/yr

Show all stations (N/E/Up + cluster)

AUST — horizontal and vertical displacement (N · E · Up) past 365 d, mm from first reading

Up = land rising (possible magma accumulation), down = subsidence. From Nevada Geodetic Lab (third-party processing, ~3-week lag, latest 2026-06-07). Interpreted deformation: Icelandic Met Office.

🌊 Volcanic tremor — The baseline tremor is currently low and should only be compared to recent days since win…

IMO tremor plot (station god). Most of the signal is weather and surf — not eruption confirmation. All stations: vedur.is ↗.

Weather now: wind 1 m/s (Reynisfjalli) — moderate.

The baseline tremor is currently low and should only be compared to recent days since wind and wave correlations are unreliable 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
2026-07-26 16:28	M-0.6	5.2	Mýrdalsjökull (Katla)
2026-07-26 16:16	M1.0	0.8	Mýrdalsjökull (Katla)
2026-07-26 15:54	M2.0	0.5	Mýrdalsjökull (Katla)
2026-07-26 15:28	M-0.4	5.2	Mýrdalsjökull (Katla)
2026-07-26 15:03	M0.4	5.2	Mýrdalsjökull (Katla)
2026-07-26 13:36	M1.0	6.5	Mýrdalsjökull (Katla)
2026-07-26 13:24	M-1.0	5.1	Mýrdalsjökull (Katla)
2026-07-26 09:03	M0.9	0.5	Mýrdalsjökull (Katla)
2026-07-26 08:41	M0.9	1.8	Mýrdalsjökull (Katla)
2026-07-26 07:58	M0.3	5.2	Mýrdalsjökull (Katla)
2026-07-26 05:56	M0.9	5.0	Mýrdalsjökull (Katla)
2026-07-26 05:16	M-0.3	5.2	Mýrdalsjökull (Katla)
2026-07-26 04:52	M0.5	5.2	Other areas
2026-07-26 01:45	M3.3	5.2	Mýrdalsjökull (Katla)
2026-07-26 01:19	M0.4	0.3	Mýrdalsjökull (Katla)
2026-07-26 00:56	M3.3	5.2	Mýrdalsjökull (Katla)
2026-07-26 00:27	M1.0	12.8	Mýrdalsjökull (Katla)
2026-07-25 23:28	M1.0	1.1	Mýrdalsjökull (Katla)
2026-07-25 22:17	M1.0	0.0	Mýrdalsjökull (Katla)
2026-07-25 22:17	M0.8	11.6	Other areas
2026-07-25 22:17	M0.5	11.6	Other areas
2026-07-25 19:25	M-0.1	8.0	Mýrdalsjökull (Katla)
2026-07-25 19:05	M0.2	1.1	Mýrdalsjökull (Katla)
2026-07-25 18:59	M-1.1	5.2	Mýrdalsjökull (Katla)
2026-07-25 17:51	M-0.3	2.7	Mýrdalsjökull (Katla)
2026-07-25 17:36	M-1.0	5.2	Mýrdalsjökull (Katla)
2026-07-25 15:13	M-0.1	2.2	Mýrdalsjökull (Katla)
2026-07-25 13:51	M1.1	1.1	Mýrdalsjökull (Katla)
2026-07-25 12:57	M-1.0	5.2	Mýrdalsjökull (Katla)
2026-07-25 12:52	M-0.9	5.2	Mýrdalsjökull (Katla)
2026-07-25 10:21	M-0.5	5.2	Mýrdalsjökull (Katla)
2026-07-25 09:17	M-0.8	5.2	Mýrdalsjökull (Katla)
2026-07-25 09:05	M-0.6	5.2	Mýrdalsjökull (Katla)
2026-07-25 08:18	M-0.6	5.2	Mýrdalsjökull (Katla)
2026-07-25 07:25	M0.7	0.0	Mýrdalsjökull (Katla)
2026-07-25 05:50	M0.3	1.1	Mýrdalsjökull (Katla)
2026-07-25 04:20	M-1.9	5.2	Mýrdalsjökull (Katla)
2026-07-25 03:32	M-1.0	3.7	Mýrdalsjökull (Katla)
2026-07-25 03:02	M-0.5	5.2	Mýrdalsjökull (Katla)
2026-07-25 02:52	M0.1	5.2	Mýrdalsjökull (Katla)
2026-07-25 02:25	M0.4	0.0	Mýrdalsjökull (Katla)
2026-07-25 02:25	M0.1	5.7	Mýrdalsjökull (Katla)
2026-07-25 02:12	M1.5	1.1	Mýrdalsjökull (Katla)
2026-07-25 01:43	M0.0	2.6	Mýrdalsjökull (Katla)
2026-07-25 01:08	M1.4	1.1	Mýrdalsjökull (Katla)
2026-07-24 22:59	M-0.1	1.1	Mýrdalsjökull (Katla)
2026-07-24 22:59	M0.4	0.0	Mýrdalsjökull (Katla)
2026-07-24 22:48	M-0.7	7.2	Mýrdalsjökull (Katla)
2026-07-24 22:46	M-0.6	5.2	Mýrdalsjökull (Katla)
2026-07-24 22:31	M0.0	2.1	Mýrdalsjökull (Katla)
2026-07-24 22:25	M-0.6	5.3	Mýrdalsjökull (Katla)
2026-07-24 22:24	M1.4	0.3	Mýrdalsjökull (Katla)
2026-07-24 22:24	M1.7	1.1	Mýrdalsjökull (Katla)
2026-07-24 22:03	M0.9	1.1	Mýrdalsjökull (Katla)
2026-07-24 22:03	M0.7	1.1	Mýrdalsjökull (Katla)
2026-07-24 22:02	M-0.3	7.6	Mýrdalsjökull (Katla)
2026-07-24 22:01	M0.8	1.1	Mýrdalsjökull (Katla)
2026-07-24 21:58	M1.2	1.1	Mýrdalsjökull (Katla)
2026-07-24 21:55	M1.2	1.1	Mýrdalsjökull (Katla)
2026-07-24 21:54	M2.6	4.6	Mýrdalsjökull (Katla)

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.

System journal

Automatic snapshots and media coverage, in chronological order. Subscribe: RSS · ntfy skjalftar-katla-myrdalsjokull

2026-07-21 08:40:06 UTC

Over the last 24 hours, 14 earthquakes were detected under Katla, a powerful central volcano beneath the Mýrdalsjökull ice cap, with activity remaining similar to the past week. This seismic activity is within what is considered normal for this area and is characterized by diffuse background activity rather than swarms, as 86% of the events over the last seven days were independent. The largest earthquake in the last 48 hours was magnitude 1.7 and the cumulative magnitude for that period was 2.0, though these results are automatic preliminary findings where depth is unreliable. The current activity most closely resembles the period around June 14, 2026 as a historical analogue, which is not intended as a prediction.

2026-07-20 22:30:05 UTC

Over the last 24 hours, 14 earthquakes were detected in Katla, a powerful central volcano under Mýrdalsjökull, with activity remaining similar to the past week but slightly higher than usual for this area. This represents scattered background activity rather than swarms, as 86% of events over the last seven days were independent, with the largest earthquake in the last 48 hours measuring magnitude 1.7 and the cumulative seismic moment for that period reaching Mw 2.0. This activity most closely resembles the period around June 13, 2026 as a historical analogue, though it must be noted that these are automatic preliminary results where depth is unreliable. Further details and maps of the area are available below.

2026-07-19 22:35:04 UTC

Over the last 24 hours, 18 earthquakes were detected under Katla, a powerful caldera volcano beneath Mýrdalsjökull, representing slightly more activity than usual for this area with 13 earthquakes measured compared to the daily average of 2.6 according to automatic preliminary results. This activity is similar to the past week and is characterized by scattered background activity rather than swarms, with the largest earthquake in the last 48 hours measuring 1.7 and the cumulative magnitude reaching 2.0. GNSS measurements show the ground subsiding by approximately 12 mm/year compared to the decadal average of 37 mm/year of uplift, with the current activity most closely resembling the period around June 13, 2026. Further details and maps can be found lower on this page.

2026-07-19 19:45:03 UTC

Over the last 24 hours, 14 earthquakes were detected under Katla, a powerful central volcano beneath Mýrdalsjökull, with activity remaining similar to the past week but still considered slightly more than usual for this area. This represents scattered background activity rather than earthquake swarms, with the largest event in the last 48 hours measuring magnitude 1.7 and the cumulative magnitude for that period being 2.0. GNSS measurements indicate the ground is subsiding by approximately 12 mm per year, though it should be noted that the earthquake results are automatic preliminary data and their depth is unreliable. This activity most closely resembles the period around June 14, 2026 as a historical analogue, and further data and maps can be found lower on the page.

2026-07-17 17:30:06 UTC

Over the last 24 hours, 10 earthquakes were detected in Katla, a powerful central volcano under Mýrdalsjökull glacier, with activity remaining similar to the past week and considered normal for this area. The largest earthquake in the last 48 hours was magnitude M3.0, with a cumulative moment magnitude of Mw 3.1 during this period, while ground deformation measurements from GNSS data a few weeks old show land subsiding by approximately 12 mm per year. The activity in the area is characterized by scattered background activity rather than swarms, closely resembling the period around June 13, 2026. Please note that these results are automatic preliminary findings with unreliable depths, but further data and maps are available below on the page.

2026-07-17 14:55:04 UTC

Over the last 24 hours, seismic activity has decreased in Katla, a powerful central volcano beneath Mýrdalsjökull glacier, with 6 earthquakes detected, which is below the weekly average. This activity is considered normal for this area and is characterized by scattered background activity rather than swarms, though the largest earthquake in the last 48 hours was magnitude M3.0 and the cumulative moment magnitude was Mw 3.1. Recent GNSS measurements indicate that the land is subsiding by approximately 12 mm per year, deviating from the decadal average where uplift has been measured at 37 mm per year. This development most closely resembles the period around June 14, 2026, but it should be noted that these are automatic preliminary results and earthquake depths are unreliable.

2026-07-17 12:20:05 UTC

Over the last 24 hours, 8 earthquakes were detected under Katla, a powerful central volcano beneath Mýrdalsjökull glacier, with activity remaining similar to the past week and within the normal range for this area. This represents scattered background activity rather than swarms, as 80% of events over the last seven days were independent, with the largest earthquake in the last 48 hours being an automatic M3.0 event and the cumulative magnitude for the period being Mw 3.1. GNSS measurements show land subsiding by approximately 12 mm per year based on seasonally adjusted data, though these results are automatic preliminary findings with unreliable depth constraints. This activity most closely resembles the period around 14 June 2026 as a historical analogue, and further details and maps can be found lower on the page.

2026-07-17 10:10:04 UTC

Over the last 24 hours, 9 earthquakes were detected under Katla, a powerful central volcano beneath Mýrdalsjökull, with activity remaining similar to the past week and considered normal for this area. This represents scattered background activity rather than swarms, as 79% of events over the last seven days were independent, though the largest earthquake in the last 48 hours was magnitude M3.0 and the cumulative moment magnitude for that period was Mw 3.1. Deformation measurements show land subsiding by approximately 12 mm per year based on several weeks old GNSS data, and the current activity most closely resembles the period around June 14, 2026. Please note that these are automatic preliminary results with unreliable depths, and further data and maps can be found lower on this page.

Repeated × 2 since 2026-07-17 05:45:04 — last 2026-07-17 08:00:06

Over the last 24 hours, seismic activity in Katla, a powerful central volcano under Mýrdalsjökull glacier, has decreased with 5 earthquakes detected, which is below the weekly average. This activity is considered normal for this area and consists mostly of scattered background activity rather than swarms, though the largest earthquake in the last 48 hours was magnitude 3.0 (M3.0) and the cumulative seismic moment for that period was 3.1 (Mw). GNSS data show the land subsiding by approximately 12 mm per year based on seasonally adjusted measurements, but these results are automatic preliminary findings where earthquake depths are unreliable. The current activity most closely resembles the period around June 14, 2026 as a historical analogue, and further details and maps can be found lower on the page.

2026-07-17 03:25:04 UTC

Over the last 24 hours, 7 earthquakes were detected in Katla, a powerful central volcano under Mýrdalsjökull, with activity remaining similar to the past week and within the normal range for this area. The largest earthquake in the last 48 hours was magnitude M3.0, with a cumulative moment magnitude of Mw 3.1 during that period, characterized by scattered background activity rather than earthquake swarms. GNSS data from a few weeks ago show land subsidence of approximately 12 mm per year, which is slower than the decadal average of 37 mm per year. This activity most closely resembles the period around June 14, 2026, though it must be noted that these are automatic preliminary results with unreliable depth estimates. Maps and further data on this development are available below.

2026-07-17 00:25:04 UTC

Over the last 24 hours, 9 earthquakes were detected in Katla, a powerful central volcano under Mýrdalsjökull glacier, with activity remaining similar to the past week and considered normal for this area. The largest earthquake in the last 48 hours was magnitude 3.0, with a cumulative seismic moment of magnitude 3.1 during that period, characterized by scattered background activity rather than swarms as 78% of events over the last seven days were independent. GNSS measurements show land subsiding by approximately 12 mm per year based on seasonally adjusted data, though these results are automatic preliminary data with unreliable depth estimates. This activity most closely resembles the period around June 14, 2026, as a historical analogue and is not a prediction of future behavior.

2026-07-16 19:50:03 UTC

Over the last 24 hours, 14 earthquakes were detected under Katla, a powerful central volcano beneath Mýrdalsjökull glacier, with activity remaining similar to the past week but slightly higher than usual for this area. This represents scattered background activity rather than earthquake swarms, with the largest event over the last 48 hours measuring magnitude 3.0 and the cumulative seismic moment magnitude for that period reaching 3.1. This activity most closely resembles the period around 13 June 2026, though it must be noted that these are automatic preliminary results with unreliable depth estimates. Further details and maps of the area are available below.

2026-07-16 11:25:03 UTC

Over the last 24 hours, 27 earthquakes were detected in Katla, a powerful central volcano beneath Mýrdalsjökull glacier, indicating increasing activity as the last 24 hours are well above the weekly average of 13 earthquakes per day. This represents slightly more activity than usual for this area and is characterized as scattered background activity rather than earthquake swarms, with the largest earthquake in the last 48 hours measuring magnitude M3.0 and the cumulative seismic moment magnitude reaching Mw 3.1. GNSS measurements from a few weeks ago show the ground subsiding by approximately 12 mm per year, and the current activity most closely resembles the period around June 13, 2026, though this is a comparison and not a prediction. Please note that these are automatic preliminary results with unreliable depths, and further data and maps can be found lower on this page.

Repeated × 2 since 2026-06-16 14:55:04 — last 2026-06-17 08:35:05

In the last 24 hours, 14 earthquakes were detected in Katla, indicating an increase above the weekly average and higher activity than usual for this area. The increase is mostly due to short-lived swarms, with the largest event at M1.9 and a cumulative magnitude of Mw 2.0 over the past 48 hours. GNSS data, which are several weeks old, show subsidence of ~21 mm/year, but these are automatic preliminary results. Activity resembles the period around September 21, 2025, and further details are available below.

2026-06-09 18:00:05 UTC

In the last 24 hours, 14 earthquakes were recorded at Katla, indicating activity similar to the past week and within normal levels for this area. The seismicity is characterized by distributed background activity rather than swarms, and these results are automatic preliminary findings. GNSS data indicate subsidence of approximately 14 mm/year after seasonal correction. Further details on trends and measurements are available below.

2026-06-08 21:40:04 UTC

In the last 24 hours, 15 earthquakes were recorded at Katla, indicating activity similar to the past week but slightly higher than usual for this area. The increase is primarily due to distributed background seismicity rather than swarms and most closely resembles the period around October 23, 2025. GNSS data indicate subsidence of approximately 15 mm/year after seasonal correction, though the data are several weeks old. These figures are automatic preliminary results, and further details are available below.

2026-06-08 19:20:04 UTC

In the last 24 hours, 17 earthquakes were recorded at Katla, indicating activity similar to the past week but slightly higher than usual for this area. The seismicity is characterized by distributed background activity rather than swarms and most closely resembles the period around October 23, 2025. GNSS data indicate subsidence of approximately 15 mm/year after seasonal correction, though the data are several weeks old. These automatic preliminary results are based solely on numerical measurements without interpretation of causes.

2026-06-08 11:00:06 UTC

In the last 24 hours, seismic activity at Katla has been similar to the past week but slightly higher than usual for this area, characterized mainly by distributed background activity rather than swarms. The largest earthquake was magnitude M2.5 with a cumulative moment of Mw 2.6 over the last 48 hours, while GNSS data indicate subsidence of approximately 15 mm/year. These automatic preliminary results most closely resemble the activity period around October 23, 2025, and further details are available below.

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).