Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.7 on date 23-02-2021 and time 04:48:13 (UTC) in region Confine Italia Francia (FRANCIA)

A magnitude ML 1.7 earthquake occured in region: Confine Italia Francia (FRANCIA), on

  • 23-02-2021 04:48:13 (UTC)
  • 23-02-2021 05:48:13 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 44.2350, 6.8650 at 8 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

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.

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Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Pietraporzio CN 18 77 77
Argentera CN 18 83 160

Municipalities with at least 50000 inhabitants

An earthquake occurred to
58 Km W of Cuneo (56081 inhabitants)
87 Km NW of Sanremo (54807 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
Bulletin
Rev1000 		ML 1.7 2021-02-23
04:48:13		 44.2347 6.8652 8 2021-07-12
16:55:06		 Bollettino Sismico Italiano INGV 89266531
Reviewed
Rev100 		ML 1.7 2021-02-23
04:48:13		 44.236 6.8605 7 2021-02-23
04:54:11		 Sala Sismica INGV-Roma 87398761
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-02-23 04:48:13 ± 0.26
Latitude 44.2347 ± 0.0081
Longitude 6.8652 ± 0.0126
Depth (km) 8 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 89266531

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1186
Semi-minor axis of confidence ellipse (meter) 425
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 53
Circular confidence region, given by single value of horizontal uncertainty (meter) 1190.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 199
Number of associated phases, regardless of their use for origin computation 19
Number of defining phases 19
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) 0.32555
Epicentral distance of station farthest from the epicenter (degree) 1.06300
Number of stations at which the event was observed 12
Number of stations from which data was used for origin computation 12
Magnitudes information

ML:1.7

Field Value
Value 1.7
Uncertainty 0.2
Num. used stations 4
Type of magnitude ML
Reference to an origin 87398761
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-02-23 04:54:11

ML:1.7

Field Value
Value 1.7
Uncertainty 0.3
Num. used stations 8
Type of magnitude ML
Reference to an origin 89266531
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-04-19 17:33:17
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
MN.BNI.HHN. 2021-02-23T04:48:41.46 0.6 undecidable manual S 351 91.8414 50 -0.14 44
GU.RRL.HHE. 2021-02-23T04:48:37.24 0.3 undecidable manual S 356 76.368 50 -0.23 67
GU.GBOS.HHZ. 2021-02-23T04:48:37.80 0.3 undecidable manual S 89 77.4669 50 0.04 70
GU.BHB.HHN. 2021-02-23T04:48:36.66 0.6 undecidable manual S 25 73.6707 50 -0.09 46
IV.QLNO.HHZ. 2021-02-23T04:48:34.56 0.6 undecidable manual P 85 117.993 50 0.66 36
GU.CANO.HHZ. 2021-02-23T04:48:33.10 0.3 undecidable manual P 91 109.113 50 0.57 58
GU.RSP.HNN. 2021-02-23T04:48:32.65 0.3 undecidable manual P 17 106.116 50 0.58 58
FR.SAOF.HHZ.00 2021-02-23T04:48:32.84 0.3 undecidable manual S 116 61.2942 50 -0.61 62
RD.ORIF.BHE. 2021-02-23T04:48:31.95 0.3 undecidable manual P 315 108.7134 50 -0.51 59
GU.IMI.HHZ. 2021-02-23T04:48:29.73 0.3 undecidable manual P 113 89.4438 50 0.23 65
MN.BNI.HHN. 2021-02-23T04:48:29.87 0.3 undecidable manual P 351 91.8414 50 0 68
GU.GBOS.HHZ. 2021-02-23T04:48:27.97 0.3 undecidable manual P 89 77.4669 50 0.32 66
GU.BHB.HHN. 2021-02-23T04:48:27.35 0.1 undecidable manual P 25 73.6707 50 0.28 89
GU.RRL.HHE. 2021-02-23T04:48:27.28 0.3 undecidable manual P 356 76.368 50 -0.2 67
GU.STV.HHE. 2021-02-23T04:48:26.48 0.3 undecidable manual S 88 36.6411 102 -0.35 70
GU.PZZ.HHE. 2021-02-23T04:48:26.50 0.3 undecidable manual S 33 36.1416 102 -0.15 73
FR.SAOF.HHZ.00 2021-02-23T04:48:24.90 0.3 undecidable manual P 116 61.2942 50 -0.26 68
GU.STV.HHE. 2021-02-23T04:48:21.30 0.1 undecidable manual P 88 36.6411 102 -0.04 100
GU.PZZ.HHE. 2021-02-23T04:48:21.36 0.1 undecidable manual P 33 36.1416 102 0.12 98
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
GU.GBOS.HHN. ML:1.4 0.00004051619 0.2784 AML other m 2021-02-23T04:48:38.09
GU.GBOS.HHE. ML:1.4 0.000041351155 0.1376 AML other m 2021-02-23T04:48:38.33
GU.IMI.HHE. ML:1.8 0.00007757537500000001 0.1184 AML other m 2021-02-23T04:48:46.52
GU.IMI.HHN. ML:1.9 0.00009305000000000001 0.14 AML other m 2021-02-23T04:48:46.94
FR.SAOF.HHE.00 ML:1.2 0.00003232266 0.1408 AML other m 2021-02-23T04:48:34.91
GU.CANO.HHN. ML:1.9 0.00007298092999999999 0.4384 AML other m 2021-02-23T04:48:55.70
GU.CANO.HHE. ML:2.0 0.00009218461 0.3808 AML other m 2021-02-23T04:48:55.36
IV.QLNO.HHN. ML:1.6 0.000027506410000000002 0.3616 AML other m 2021-02-23T04:48:57.13
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