Tjörnes Fracture Zone
Zone — systems within: Tjörnes / Grímsey · Eyjafjarðaráll · Kolbeinseyjarhryggur
Points = earthquake locations in the selected window, coloured by magnitude: M3+ · M2+ · smaller (a sample if more than 800).
Earthquakes
14
Largest
M2.7
M3,0+
0
Depth range
0–19 km
Earthquakes over time
Cumulative count · 14 earthquakes · total moment ≈ M2.8 · 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.
Earthquakes
24
Largest
M2.7
M3,0+
0
Depth range
0–19 km
Earthquakes over time
Cumulative count · 24 earthquakes · total moment ≈ M2.8 · 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.
Earthquakes
60
Largest
M2.7
M3,0+
0
Depth range
0–28 km
Earthquakes over time
Cumulative count · 60 earthquakes · total moment ≈ M2.8 · count moment
No significant hypocenter migration — activity is stationary (R²=0.00, n=60); 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
177
Largest
M2.8
M3,0+
0
Depth range
0–28 km
Earthquakes over time
Cumulative count · 177 earthquakes · total moment ≈ M3.0 · 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
563
Largest
M2.9
M3,0+
0
Depth range
0–28 km
Earthquakes over time
Cumulative count · 563 earthquakes · total moment ≈ M3.3 · 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
1549
Largest
M2.9
M3,0+
0
Depth range
0–28 km
Earthquakes over time
Cumulative count · 1549 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.
Gutenberg-Richter b ≈ 1.48 ± 0.20 (i.e. likely 1.28–1.68, M≥1.7, n=62)
Earthquakes
2599
Largest
M2.9
M3,0+
0
Depth range
0–28 km
Earthquakes over time
Cumulative count · 2599 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.
Gutenberg-Richter b ≈ 1.40 ± 0.12 (i.e. likely 1.28–1.52, M≥1.7, n=112)
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
7114
Largest
M4.7
M3,0+
10
Depth range
0–28 km
Earthquakes over time
Cumulative count · 7114 earthquakes · total moment ≈ M4.7 · 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 ≈ 1.16 ± 0.06 (i.e. likely 1.10–1.22, M≥1.7, n=386)
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
32.697
Largest
M4.7
M3.0+
269
Days with data
1.784
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 5.3
Magnitude distribution
<110039
1–216645
2–32534
3–4256
≥413
Gutenberg-Richter b ≈ 1.03 ± 0.01 (i.e. likely 1.02–1.04, M≥1.7, n=5865)
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
87.870
Largest
M5.0
M3.0+
767
Days with data
3.594
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 5.7
Magnitude distribution
<135785
1–241255
2–36628
3–4721
≥446
Gutenberg-Richter b ≈ 0.95 ± 0.01 (i.e. likely 0.94–0.96, M≥1.7, n=14094)
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
140.909
Largest
M5.7
M3.0+
1307
Days with data
7.116
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 6.1
Magnitude distribution
<155713
1–267889
2–312512
3–41219
≥488
Gutenberg-Richter b ≈ 0.94 ± 0.01 (i.e. likely 0.94–0.95, M≥1.7, n=25474)
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
196.406
Largest
M5.7
M3.0+
1737
Days with data
11.122
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 6.2
Magnitude distribution
<176756
1–296660
2–317743
3–41627
≥4110
Gutenberg-Richter b ≈ 0.96 ± 0.00 (i.e. likely 0.95–0.96, M≥1.7, n=36164)
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.