THE NETHERLANDS

Known induced event16 August 2012

Magnitude
4.0ML
Depth
10.0km
Belgian time
22:30:342012-08-16
UTC
20:30:342012-08-16

Main parameters

Magnitude and intensity

Two numbers often confused, with the values of this earthquake and of the Observatory’s catalogue.

Preparing the animation…

1Magnitude: the size of the earthquake

The magnitude (ML 4.0) measures the size of the earthquake at its source, from the amplitude of the waves recorded by seismographs: a single value for the whole earthquake. Since 1985, 99 % of the 3,122 earthquakes with a magnitude in the Observatory’s catalogue have a smaller one.

Animation drawn from the page and the Observatory’s catalogue (tectonic earthquakes since 1985, ML or MW magnitudes); short descriptions of the European Macroseismic Scale EMS-98.

Date and time2012-08-16 20:30:34 UTC
2012-08-16 22:30:34 Belgian time
MagnitudeML 4.0
Epicentral coordinates53.373° N, 6.487° E
Uncertainty ± 3.8 km
Depth of hypocenter10.0 km
Event IDROB 4763

Data source : ROB (Royal Observatory of Belgium)
Last update : 2012-11-12 15:09:57 Belgian time

Location map

Where and when the earthquake began

The focus, the epicentre and their uncertainties, with this earthquake’s values.

Preparing the animation…

1Focus and epicentre

An earthquake starts at depth, at the focus (or hypocentre): here 10 km below the surface. The point on the surface right above it is the epicentre (53.373° N, 6.487° E), the one the map shows.

Values from the page and the Observatory’s catalogue (tectonic earthquakes since 1985).

  • Epicentre
  • Station that recorded the event

Macroseismic inquiry

How the macroseismic inquiry works

Using the answers to the “Did you feel an earthquake?” questionnaire for this earthquake.

Preparing the animation…

1Testimonies

4 answers to the online questionnaire were received for this earthquake, from 4 municipalities (Belgium, Germany). Each dot is a municipality, larger when it has more answers; the farthest, HAACHT, is 295 km from the epicentre.

Animation drawn from this earthquake’s answers, with the calculation of the page’s map and chart (ROB method).

Intensities derived from the answers to the online questionnaire “Did you feel an earthquake?”, grouped by municipality (former municipalities included). The map and the chart give the intensity of each municipality.

Answers
10
Municipalities
4
Farthest municipality
295km · HAACHT
Countries
Belgium, Germany
Grouping
Show
Intensity of the municipality (CII)
  • I
  • II
  • III
  • IV
  • V
  • VI
  • VII+
Answers per municipality
  • 3–4
  • 5–9
  • 10–19
  • 20–49
  • ≥ 50
  • felt, fewer than 3 answers
  • Epicentre

Answers by intensity

IntensityAnswers
I3
II5
III2
Total10

Intensity against distance

  • Intensity of the municipality (CII)

Warning: the intensities derived from the inquiry are raw, unverified data.

Notes and method

Intensity of a municipality or a cell (CII, Community Internet Intensity) is computed as follows:

  • I if no answer reports that the earthquake was felt;
  • F earthquake felt, but fewer than 3 answers kept per municipality or cell;
  • II–IX computed from 3 answer(s) kept: CII = 3.40 ln(CWS) − 4.38 (Wald et al., 1999), applied to the weighted sum (CWS) of the mean indexes of the answers; at least II if felt, at most IX.

Answers kept (USGS method, as applied by the ROB): reliability of 80 or more, given on the ground floor up to the 4th floor (or unknown floor), without those more than two standard deviations from the mean. The “felt” index is weighted by the answer to “Did others nearby feel it?”.

Distribution by intensity: macroseismic intensity (MI) recorded for each answer.

Cells: 5 or 10 km squares of the Belgian Lambert 72 grid, each answer placed at its geocoded address or at the point it placed on the map, otherwise at the centre of its municipality. The positions of the answers are published only rounded to about 1 km, in “Arrival of the answers”. Grid cell method: Van Noten et al. (2017), Solid Earth 8, 453–477, doi:10.5194/se-8-453-2017.

Answers without a known municipality, left out of the map and the chart: 6.

Answers read on 2026-11-09 10:08.

Seismic activity in the area

Known earthquakes around the epicentre, from the catalogue of the Royal Observatory of Belgium.

Within 10 km of the epicentre

4 other earthquakes in the catalogue since 2011. 3 of them occurred after this one. This is the largest known earthquake in the area.

Latest earthquakes before this one

DatePlaceMagnitudeIntensityDistance km
2011-06-27THE NETHERLANDSinducedML 3.7–2.6

Largest known earthquakes

DatePlaceMagnitudeIntensityDistance km
2012-08-16This earthquakeinducedML 4.0––
2011-06-27THE NETHERLANDSinducedML 3.7–2.6
2013-02-07NederlandinducedML 3.3–6.8
2020-07-14GRONINGEN (NL)inducedML 2.9–6.9
2020-07-19GRONINGEN (NL)inducedML 2.6–3.8

Nearest beyond 10 km

DatePlaceMagnitudeIntensityDistance km
2019-05-22GRONINGEN (NL)inducedML 3.4–12.1
2022-10-08GRONINGEN (NL)inducedML 2.5–12.4
2026-08-21ROTTUM (NL)inducedML 2.5–12.6
2025-11-14GRONINGEN (NL)inducedML 3.4–16.9
2018-01-08T ZANDT (NL)inducedML 3.4–18.2
Notes and method

Tectonic and induced earthquakes from the Observatory’s catalogue, suspected ones included; quarry blasts, explosions and other events are not counted. Epicentral distances on the WGS84 ellipsoid.

Municipality: 2025 municipal boundaries (Statbel), applied to every earthquake, including those before the merger of municipalities. For an epicentre outside Belgium, only the circular area is given. Each earthquake’s name is the catalogue’s: it may refer to a place near the epicentre.

Magnitude: the one given on each earthquake’s page (ML preferably, otherwise MW or MS); magnitudes of different types are compared as they are.

The epicentres of historical earthquakes are only known to within a few kilometres, sometimes more: whether they fall in the area is indicative. Small earthquakes have only been recorded as the station network grew: the area’s older earthquakes are mostly the largest ones, and recent activity looks more frequent.

When the area holds fewer than 5 other earthquakes, the nearest ones beyond 10 km are listed too, up to 100 km. Sequences (aftershocks, swarms) take a single row there, that of their largest earthquake: an earthquake joins a sequence if it occurs at most 7 days after the previous one and within 5 km of the first.

Arrival times at the stations

Each station first records the P wave, the fastest, then the S wave. The farther a station is from the epicentre, the later the waves reach it and the wider the gap between the two.

Stations
34
Epicentral distance
63.4 – 885.8km
  • P wave
  • S wave

Table of measurements

Station measurements

P- and S-wave arrivals and ground displacement measured at each station. Click a column heading to change the order.

km°UTCUTCsnm
Belgian seismic network (Royal Observatory of Belgium)25 stations
HRKHerkenbosch244.118520:31:09.22+35.02 s–––
DSLBDessel257.220320:31:10.11+35.91 s20:31:48.86+74.66 s38.7595.9
EBNEben-Emael291.919120:31:14.66+40.46 s–––
MEMSMembach309.318620:31:16.61+42.41 s20:31:50.31+76.11 s33.70–
STISart Tilman316.819220:31:17.81+43.61 s–––
CLAClavier338.619420:31:20.53+46.33 s20:31:56.99+82.79 s36.46–
RQRRonquières344.820820:31:22.58+48.38 s–––
SKQSteenkerque345.221020:31:22.58+48.38 s20:31:58.52+84.32 s35.94–
GESGesves346.119720:31:21.41+47.21 s20:31:59.27+85.07 s37.86–
LESLessines347.321320:31:22.61+48.41 s–––
SNFSeneffe352.620620:31:23.36+49.16 s–––
BRQBracquegnies360.120820:31:24.26+50.06 s–––
MRDMaredsous361.620020:31:23.68+49.48 s–––
KLBKalborn365.118420:31:24.17+49.97 s–––
MN8Mons - Université de Mons367.620920:31:25.80+51.60 s20:32:04.67+90.47 s38.87–
MN6Mons - Muséum régional des Sciences naturelles368.420920:31:26.12+51.92 s20:32:20.96+106.76 s54.84–
RCHRochefort368.419420:31:23.92+49.72 s20:32:19.11+104.91 s55.1982.7
MN1Mons - Lotto Mons Expo368.620920:31:26.38+52.18 s20:32:05.34+91.14 s38.96–
MN2Mons - Cité administrative368.9209–20:32:06.60+92.40 s––
MN5Mons - RW (DPA)369.320920:31:25.27+51.07 s20:32:19.21+105.01 s53.94–
MN9Mons - SWDE369.920920:31:26.32+52.12 s20:32:06.01+91.81 s39.69–
BOUBougnies375.320920:31:26.27+52.07 s20:32:23.59+109.39 s57.32–
VIAVianden383.018320:31:26.32+52.12 s20:32:04.17+89.97 s37.85–
DOUDourbes387.420020:31:27.20+53.00 s20:32:01.76+87.56 s34.56–
WLFWalferdange413.318320:31:30.16+55.96 s20:32:12.79+98.59 s42.63–
Dutch seismic network (KNMI)3 stations
WITWitteveen63.416920:30:44.89+10.69 s–––
WTSWinterswijk154.817220:30:59.74+25.54 s–––
HGNHeimansgroeve292.818820:31:14.96+40.76 s–––
Network PRU3 stations
NKCNovy Kostel539.212820:31:48.51+74.31 s–––
PRUPruhonice671.812120:32:03.81+89.61 s–––
KHCKasperske Hory683.413120:32:06.41+92.21 s–––
British Geological Survey (United Kingdom)1 station
KPLPLOCKTON885.830520:32:29.86+115.66 s–––
Network STU1 station
STUSTUTTGART545.815920:31:49.44+75.24 s–––
Network not specified1 station
GALgalenberg330.017120:32:13.18+98.98 s–––
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