HEIST-AAN-ZEE (BE)
Suspected mine explosion23 July 2012
- Magnitude
- 1.9ML
- Depth
- 1.0km
- Belgian time
- 12:20:262012-07-23
- UTC
- 10:20:262012-07-23
Main parameters
| Date and time | 2012-07-23 10:20:26 UTC 2012-07-23 12:20:26 Belgian time |
|---|---|
| Magnitude | ML 1.9 |
| Epicentral coordinates | 51.440° N, 3.238° E Uncertainty ± 3.2 km |
| Depth of hypocenter | 1.0 km |
| Event ID | ROB 4750 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2012-07-24 13:58:55 Belgian time
Location map
- Epicentre
- Station that recorded the event
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
- 15
- Epicentral distance
- 41.1 – 184.2km
- Mean velocity, P wave
- 5.8km/s
- Mean velocity, S wave
- 3.5km/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 1.0 km. P wave: 5 measurements, root-mean-square deviation 0.20 s. S wave: 4 measurements, root-mean-square deviation 0.49 s.
Stations farther than 120 km are left out of the fit: the first waves to reach them have travelled beneath the crust, through the mantle, where they propagate faster.
Station measurements
P- and S-wave arrivals and ground displacement measured at each station. Click a column heading to change the order.
| km | ° | UTC | UTC | s | nm | |
|---|---|---|---|---|---|---|
| Belgian seismic network (Royal Observatory of Belgium)15 stations | ||||||
| ZEVZevekote | 41.1 | 215 | 10:20:33.03+6.96 s | – | – | – |
| LESLessines | 91.5 | 152 | 10:20:41.88+15.81 s | 10:20:53.13+27.06 s | 11.25 | – |
| SKQSteenkerque | 105.9 | 146 | 10:20:44.23+18.16 s | 10:20:56.54+30.47 s | 12.31 | 20.3 |
| RQRRonquières | 115.7 | 143 | 10:20:46.03+19.96 s | 10:20:58.75+32.68 s | 12.72 | – |
| MN8Mons - Université de Mons | 119.8 | 155 | 10:20:47.18+21.11 s | 10:21:00.71+34.64 s | 13.53 | – |
| MN2Mons - Cité administrative | 120.1 | 156 | – | 10:21:02.16+36.09 s | – | – |
| MN9Mons - SWDE | 121.4 | 156 | 10:20:47.25+21.18 s | 10:21:03.13+37.06 s | 15.88 | – |
| SNFSeneffe | 126.7 | 144 | 10:20:47.79+21.72 s | 10:21:03.37+37.30 s | 15.58 | – |
| BOUBougnies | 127.0 | 157 | 10:20:47.58+21.51 s | – | – | – |
| DSLBDessel | 129.4 | 100 | 10:20:47.81+21.74 s | 10:21:03.08+37.01 s | 15.27 | – |
| CSECourt-Saint-Etienne | 132.0 | 134 | 10:20:48.99+22.92 s | 10:21:05.18+39.11 s | 16.19 | – |
| MRDMaredsous | 166.1 | 139 | 10:20:54.38+28.31 s | – | – | – |
| GESGesves | 175.1 | 131 | 10:20:54.30+28.23 s | 10:21:14.09+48.02 s | 19.79 | – |
| DOUDourbes | 177.6 | 147 | 10:20:54.47+28.40 s | – | – | – |
| CLAClavier | 184.2 | 127 | 10:20:55.71+29.64 s | – | – | – |