Earthquake with magnitude of ML 0.9 on date 22-08-2021 and time 03:00:14 (Italy) in region Costa Ligure Occidentale (Imperia)

A magnitude ML 0.9 earthquake occured in region: Costa Ligure Occidentale (Imperia), on

  • 22-08-2021 01:00:14 (UTC)
  • 22-08-2021 03:00:14 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.019, 7.634 at 10 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
Pigna IM 10 859 859
Castel Vittorio IM 10 287 1146
Triora IM 11 355 1501
Molini di Triora IM 12 617 2118
Briga Alta CN 12 39 2157
Bajardo IM 14 312 2469
Rocchetta Nervina IM 15 298 2767
Mendatica IM 15 185 2952
Isolabona IM 15 679 3631
Apricale IM 15 629 4260
Montegrosso Pian Latte IM 16 118 4378
Cosio d'Arroscia IM 17 221 4599
Perinaldo IM 17 870 5469
Airole IM 17 407 5876
Olivetta San Michele IM 18 211 6087
Ceriana IM 19 1250 7337
Dolceacqua IM 19 2074 9411
Rezzo IM 19 366 9777
Montalto Ligure IM 20 377 10154
Carpasio IM 20 168 10322
Pornassio IM 20 685 11007

Municipalities with at least 50000 inhabitants

An earthquake occurred to
25 Km NW of Sanremo (54807 inhabitants)
42 Km S of Cuneo (56081 inhabitants)
75 Km W of Savona (61345 inhabitants)
Recent and historical seismicity
Seismic hazard
Shakemap
Felt maps
Preliminary map of the earthquake effects from the web questionnaire

Preliminary map of the earthquake effects from the web questionnaire

This map shows the distribution of the effects of the earthquake on the territory in terms of the MCS (Mercalli-Cancani-Sieberg) intensity scale. The intensities are determined using the data provided in the questionnaire (http://www.haisentitoilterremoto.it/) that are analysed using robust statistical techniques since they are not verified individually. Specifically, the assignment of MCS intensities greater or equal the VI degree of the MCS scale require opportune in situ verification by professional experts. The purple start shows the epicenter. This map is prepared every so often that the population fill in new questionnaires. The number of questionnaires used to determine the map and the date and time of the last adjournment are shown in the upper right part of the panel.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 0.9 2021-08-22
01:00:14
44.019 7.6343 10 2021-08-22
01:07:26
Sala Sismica INGV-Roma 94479651
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-22 01:00:14 ± 0.09
Latitude 44.0190 ± 0.0081
Longitude 7.6343 ± 0.0063
Depth (km) 10 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 94479651

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 808
Semi-minor axis of confidence ellipse (meter) 509
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 177
Circular confidence region, given by single value of horizontal uncertainty (meter) 810
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 75
Number of associated phases, regardless of their use for origin computation 17
Number of defining phases 17
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.29
Epicentral distance of station closest to the epicenter (degree) 0.06745
Epicentral distance of station farthest from the epicenter (degree) 0.47214
Number of stations at which the event was observed 9
Number of stations from which data was used for origin computation 9
Magnitude information

ML:0.9

Field Value
Value 0.9
Uncertainty 0.2
Num. used stations 22
Type of magnitude ML
Reference to an origin 94479651
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-08-22 01:07:26
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
GU.RORO.HHZ. 2021-08-22T01:00:26.69 0.3 undecidable manual S 73 0.3238 50 -0.46 66
GU.STV.HHZ. 2021-08-22T01:00:26.52 0.3 undecidable manual S 316 0.3157 50 -0.39 67
GU.GBOS.HHZ. 2021-08-22T01:00:25.10 0.3 undecidable manual S 33 0.2671 50 -0.36 68
GU.BURY.HHZ. 2021-08-22T01:00:24.57 0.3 undecidable manual S 193 0.2428 109 -0.08 73
GU.ENR.HHZ. 2021-08-22T01:00:24.99 0.3 undecidable manual S 324 0.2617 50 -0.3 69
GU.CANO.HHZ. 2021-08-22T01:00:24.89 0.3 undecidable manual P 66 0.4721 50 0.46 64
GU.IMI.HHZ. 2021-08-22T01:00:23.28 0.3 undecidable manual S 120 0.2158 112 -0.38 69
GU.STV.HHZ. 2021-08-22T01:00:22.11 0.1 undecidable manual P 316 0.3157 50 0.34 91
GU.RORO.HHZ. 2021-08-22T01:00:22.09 0.3 undecidable manual P 73 0.3238 50 0.18 70
GU.GBOS.HHZ. 2021-08-22T01:00:21.24 0.3 undecidable manual P 33 0.2671 50 0.31 69
GU.ENR.HHZ. 2021-08-22T01:00:21.14 0.3 undecidable manual P 324 0.2617 50 0.31 69
GU.BURY.HHZ. 2021-08-22T01:00:20.63 0.3 undecidable manual P 193 0.2428 109 0.17 71
GU.MGRO.HHZ. 2021-08-22T01:00:20.55 0.3 undecidable manual S 79 0.1268 124 -0.09 74
GU.IMI.HHZ. 2021-08-22T01:00:19.98 0.1 undecidable manual P 120 0.2158 112 0.09 97
GU.MGRO.HHZ. 2021-08-22T01:00:18.39 0.1 undecidable manual P 79 0.1268 124 0.25 96
FR.SAOF.HHZ.00 2021-08-22T01:00:18.50 0.3 undecidable manual S 241 0.0674 142 -0.42 70
FR.SAOF.HHZ.00 2021-08-22T01:00:17.25 0.1 undecidable manual P 241 0.0674 142 0.1 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
FR.SAOF.HHE.00 ML:1.1 0.00018586475 0.18 AML other m 2021-08-22T01:00:18.50
FR.SAOF.HHN.00 ML:1.2 0.00025097895 0.22 AML other m 2021-08-22T01:00:19.38
GU.MGRO.HHN. ML:0.9 8.442491E-5 0.82 AML other m 2021-08-22T01:00:21.03
GU.MGRO.HHE. ML:0.6 3.92517E-5 0.5 AML other m 2021-08-22T01:00:21.41
GU.IMI.HHE. ML:1 6.027219E-5 0.16 AML other m 2021-08-22T01:00:23.73
GU.BURY.HHN. ML:0.7 3.031847E-5 0.1904 AML other m 2021-08-22T01:00:25.03
GU.IMI.HHN. ML:1.1 8.31482E-5 0.56 AML other m 2021-08-22T01:00:24.03
GU.ENR.HHN. ML:1 5.484104E-5 0.14 AML other m 2021-08-22T01:00:25.28
GU.ENR.HHE. ML:1 5.070747E-5 0.16 AML other m 2021-08-22T01:00:25.28
GU.GBOS.HHE. ML:0.6 2.137819E-5 0.12 AML other m 2021-08-22T01:00:25.38
GU.GBOS.HHN. ML:0.6 2.09E-5 0.1 AML other m 2021-08-22T01:00:25.48
GU.BURY.HHE. ML:0.9 4.5498445E-5 0.3504 AML other m 2021-08-22T01:00:25.16
GU.STV.HHE. ML:1 3.77E-5 0.22 AML other m 2021-08-22T01:00:27.30
GU.STV.HHN. ML:0.9 3.545E-5 0.2 AML other m 2021-08-22T01:00:27.42
GU.MGRO.HNE. ML:0.7 4.805574E-5 0.32 AML other m 2021-08-22T01:00:21.83
GU.MGRO.HNN. ML:0.8 7.089165E-5 0.78 AML other m 2021-08-22T01:00:21.03
GU.BURY.HNE. ML:1 5.532597E-5 0.8304 AML other m 2021-08-22T01:00:25.12
GU.BURY.HNN. ML:1.1 7.190183E-5 0.5 AML other m 2021-08-22T01:00:25.41
GU.RORO.HHE. ML:2 0.00042808705 2.68 AML other m 2021-08-22T01:00:26.64
GU.RORO.HHN. ML:0.6 1.5226595E-5 0.14 AML other m 2021-08-22T01:00:27.12
GU.CANO.HHE. ML:1.4 5.283364E-5 0.86 AML other m 2021-08-22T01:00:31.13
GU.CANO.HHN. ML:1 2.263411E-5 0.26 AML other m 2021-08-22T01:00:33.39
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