? ROERMOND (NL)

Earthquake23 April 1992

Magnitude
–
Depth
21.1km ± 1.9
Belgian time
18:19:391992-04-23
UTC
16:19:391992-04-23

Main parameters

Date and time1992-04-23 16:19:39 UTC
1992-04-23 18:19:39 Belgian time
Magnitude–
Epicentral coordinates51.215° N, 6.006° E
Uncertainty ± 2.3 km
Depth of hypocenter21.1 ± 1.9 km
Event IDROB 3643

Data source : ROB (Royal Observatory of Belgium)
Last update : 2024-04-24 12:46:37 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 21.1 km below the surface. The point on the surface right above it is the epicentre (51.215° N, 6.006° 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

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

150 other earthquakes in the catalogue since 1851. 89 of them occurred after this one.

Latest earthquakes before this one

DatePlaceMagnitudeIntensityDistance km
1992-04-22? MONTFORT (NL)––6.0
1992-04-21MONTFORT (NL)ML 1.5–7.2
1992-04-21ROERMOND(N)ML 1.9–5.9
1992-04-20ROERMOND(N)ML 2.0–5.9
1992-04-20ROERMOND (NL)ML 1.9–5.1

Largest known earthquakes

DatePlaceMagnitudeIntensityDistance km
1992-04-13ROERMOND (NL)ML 5.878.8
1935-01-04ROERMOND (N)MS 3.868.5
1992-04-13ROERMOND(N)ML 3.4–7.9
1992-04-13ROERMOND(N)ML 3.2–7.9
1993-06-03ROERMOND(N)ML 3.2–7.2
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.

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
13
Epicentral distance
5.5 – 118.7km
Mean velocity, P wave
6.4km/s
  • P wave
  • S wave
  • Curve fitted to the measurements
Notes and method

Curves: travel time of a direct wave in a homogeneous medium. The velocity of each wave and an origin-time shift, common to both, are fitted to the measurements by least squares. Hypocenter at a depth of 21.1 km. P wave: 13 measurements, root-mean-square deviation 0.26 s.

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°UTCUTCs
Belgian seismic network (Royal Observatory of Belgium)3 stations
THNTHORN12.824316:19:43.82+3.94 s16:19:47.07+7.19 s3.25
KINKinrooi18.024416:19:44.17+4.29 s16:19:47.70+7.82 s3.53
WIBWibrin118.719016:19:59.00+19.12 s––
Dutch seismic network (KNMI)1 station
ASNAZENRAY7.915516:19:43.68+3.80 s––
Network JCK1 station
GSHGrosshau59.415416:19:50.35+10.47 s16:19:57.52+17.64 s7.17
Network not specified8 stations
ST3ST3 - STRASBOURG5.535616:19:43.88+4.00 s––
LRPLerop6.419916:19:43.80+3.92 s––
ST2ST2 - STRASBOURG7.815016:19:43.99+4.11 s––
ST4ST4 - STRASBOURG13.820716:19:43.87+3.99 s––
ST7ST7 - STRASBOURG15.629816:19:44.22+4.34 s––
ST1ST1 - STRASBOURG16.626816:19:44.03+4.15 s––
ST8ST8 - STRASBOURG19.618916:19:44.55+4.67 s––
ST6ST627.923816:19:45.10+5.22 s––
Did you feel an earthquake?The inquiry takes just a few minutes. Every report helps seismologists assess the effects of the earthquake.
Take the inquiry