FRASNES-LEZ-ANVAING (BE)
Quarry blast22 February 2023
- Magnitude
- 1.7ML
- Depth
- –
- Belgian time
- 12:30:562023-02-22
- UTC
- 11:30:562023-02-22
Main parameters
| Date and time | 2023-02-22 11:30:56 UTC 2023-02-22 12:30:56 Belgian time |
|---|---|
| Magnitude | ML 1.7 |
| Epicentral coordinates | 50.698° N, 3.527° E Uncertainty ± 9.3 km |
| Event ID | ROB 18845 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2023-02-25 15:35:21 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
- 7
- Epicentral distance
- 39.4 – 129.5km
- Mean velocity, P wave
- 6.0km/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. Depth not determined: hypocenter placed at the surface for the calculation. P wave: 6 measurements, root-mean-square deviation 0.07 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 | |
|---|---|---|---|---|---|
| Belgian seismic network (Royal Observatory of Belgium)7 stations | |||||
| SKQSteenkerque | 39.4 | 98 | 11:31:03.80+6.99 s | 11:31:09.47+12.66 s | 5.67 |
| BRQBracquegnies | 49.4 | 119 | 11:31:05.47+8.66 s | – | – |
| RQRRonquières | 50.4 | 101 | 11:31:05.47+8.66 s | – | – |
| TGATangissart | 71.1 | 98 | 11:31:09.16+12.35 s | 11:31:18.07+21.26 s | 8.91 |
| DOUDourbes | 101.3 | 131 | 11:31:14.17+17.36 s | 11:31:26.76+29.95 s | 12.59 |
| GESGesves | 115.9 | 107 | 11:31:16.52+19.71 s | – | – |
| CLAClavier | 129.5 | 103 | 11:31:18.90+22.09 s | – | – |