Earthquake with magnitude of ML 1.0 on date 20-04-2023 and time 16:50:00 (Italy) in region Costa Ligure Occidentale (Imperia)

A magnitude ML 1.0 earthquake occured in region: Costa Ligure Occidentale (Imperia), on

  • 20-04-2023 14:50:00 (UTC)
  • 20-04-2023 16:50:00 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.7670, 7.6900 at 9 km depth.

The earthquake was located by: Sala Sismica INGV-Roma.

Search earthquakes: Any within 30 km radius

The values of hypocentral coordinates and magnitude may be revised at a later time as more information becomes available.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Bordighera IM 2 10469 10469
Ospedaletti IM 5 3367 13836
Vallecrosia IM 5 6956 20792
Vallebona IM 6 1310 22102
San Biagio della Cima IM 7 1329 23431
Seborga IM 7 315 23746
Ventimiglia IM 7 24310 48056
Soldano IM 7 977 49033
Camporosso IM 7 5632 54665
Sanremo IM 10 54807 109472
Dolceacqua IM 11 2074 111546
Perinaldo IM 11 870 112416
Apricale IM 13 629 113045
Isolabona IM 13 679 113724
Ceriana IM 15 1250 114974
Bajardo IM 16 312 115286
Rocchetta Nervina IM 16 298 115584
Taggia IM 16 14116 129700
Airole IM 16 407 130107
Riva Ligure IM 17 2910 133017
Castellaro IM 18 1256 134273
Castel Vittorio IM 18 287 134560
Santo Stefano al Mare IM 19 2197 136757
Pompeiana IM 19 823 137580
Pigna IM 19 859 138439
Olivetta San Michele IM 19 211 138650
Terzorio IM 19 216 138866

Municipalities with at least 50000 inhabitants

An earthquake occurred to
10 Km SW of Sanremo (54807 inhabitants)
71 Km S of Cuneo (56081 inhabitants)
87 Km SW of Savona (61345 inhabitants)
Recent and historical seismicity
Seismic hazard
Shakemap
Felt maps
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 1.0 2023-04-20
14:50:00
43.7667 7.6903 9 2023-04-20
15:02:59
Sala Sismica INGV-Roma 116553251
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2023-04-20 14:50:00 ± 0.17
Latitude 43.7667 ± 0.0090
Longitude 7.6903 ± 0.0062
Depth (km) 9 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 116553251

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1001
Semi-minor axis of confidence ellipse (meter) 447
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 168
Circular confidence region, given by single value of horizontal uncertainty (meter) 1000.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 234
Number of associated phases, regardless of their use for origin computation 22
Number of defining phases 15
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.22
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.54499
Number of stations at which the event was observed 15
Number of stations from which data was used for origin computation 8
Magnitude information

ML:1.0

Field Value
Value 1.0
Uncertainty 0.2
Num. used stations 9
Type of magnitude ML
Reference to an origin 116553251
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2023-04-20 15:02:59
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.MSRU.HHZ. 2023-04-20T14:51:56.35 3.0 positive manual Pn -3.28 0
IV.IMOL.HNZ. 2023-04-20T14:51:37.57 3.0 undecidable manual Sg 7.8 0
IV.GIUL.HHZ. 2023-04-20T14:51:19.83 3.0 negative manual Pg 6.81 0
IV.RIBO.EHZ.01 2023-04-20T14:51:18.58 3.0 undecidable manual Sg -0.85 0
IV.CSP1.EHZ. 2023-04-20T14:51:10.79 3.0 undecidable manual Pg 5.48 0
IV.SSFR.HHZ. 2023-04-20T14:51:03.50 3.0 undecidable manual Pn 3.08 0
IV.GUMA.HHZ. 2023-04-20T14:51:03.49 3.0 positive manual Pn -3.19 0
GU.STV.HHZ. 2023-04-20T14:50:19.49 0.3 undecidable manual S 331 60.495 50 0.02 70
GU.GBOS.HHZ. 2023-04-20T14:50:17.79 0.3 undecidable manual S 13 54.0015 50 0.05 70
GU.RORO.HHZ. 2023-04-20T14:50:15.79 0.3 undecidable manual S 38 48.7179 50 -0.54 64
GU.MGRO.HHZ. 2023-04-20T14:50:11.83 0.1 undecidable manual S 17 32.0457 50 -0.04 98
GU.STV.HHZ. 2023-04-20T14:50:11.60 0.3 undecidable manual P 331 60.495 50 0.2 67
GU.GBOS.HHZ. 2023-04-20T14:50:11.15 0.6 undecidable manual P 13 54.0015 50 0.75 39
GU.ENR.HHZ. 2023-04-20T14:50:10.51 0.6 undecidable manual P 337 55.6998 50 -0.15 46
FR.SAOF.HHZ.00 2023-04-20T14:50:10.24 0.3 undecidable manual S 336 26.6511 108 0.1 73
GU.RORO.HHZ. 2023-04-20T14:50:09.67 0.3 undecidable manual P 38 48.7179 50 0.08 71
GU.IMI.HHZ. 2023-04-20T14:50:08.87 0.1 undecidable manual S 45 22.755 111 0.01 100
GU.MGRO.HHZ. 2023-04-20T14:50:07.08 0.3 undecidable manual P 17 32.0457 50 0.07 73
GU.IMI.HHZ. 2023-04-20T14:50:05.42 0.3 undecidable manual P 45 22.755 111 0.15 73
GU.BURY.HHZ. 2023-04-20T14:50:05.19 0.3 undecidable manual S 279 10.7781 129 -0.05 76
FR.SAOF.HHZ.00 2023-04-20T14:50:05.76 0.3 undecidable manual P 336 26.6511 108 -0.25 71
GU.BURY.HHZ. 2023-04-20T14:50:03.08 0.1 undecidable manual P 279 10.7781 129 -0.11 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
GU.IMI.HHE. ML:1.4 0.000187 1.72 AML other m 2023-04-20T14:50:09.05
GU.IMI.HHN. ML:1.2 0.00009272098 0.0832 AML other m 2023-04-20T14:50:09.67
FR.SAOF.HHE.00 ML:0.8 0.00003744193 0.0576 AML other m 2023-04-20T14:50:10.92
FR.SAOF.HHN.00 ML:0.7 0.000029691759999999996 0.0384 AML other m 2023-04-20T14:50:10.81
GU.BURY.HHE. ML:1.1 0.00017345044999999998 0.0576 AML other m 2023-04-20T14:50:05.46
GU.BURY.HHN. ML:1.3 0.0002570186 0.0576 AML other m 2023-04-20T14:50:05.33
GU.MGRO.HHE. ML:1.0 0.000043700860000000004 0.2432 AML other m 2023-04-20T14:50:12.31
GU.RORO.HHE. ML:1.0 0.00002566695 1.2032 AML other m 2023-04-20T14:50:16.47
GU.RORO.HHN. ML:0.9 0.000018532315 0.1216 AML other m 2023-04-20T14:50:19.06
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download