Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.5 on date 20-09-2021 and time 18:21:31 (UTC) in region Costa Romagnola meridionale (Rimini, Forli Cesena)

A magnitude ML 1.5 earthquake occured in region: Costa Romagnola meridionale (Rimini, Forli Cesena), on

  • 20-09-2021 18:21:31 (UTC)
  • 20-09-2021 20:21:31 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.1280, 12.8180 at 23 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.

Hai sentito il terremoto? Clicca qui

Did you feel it? Fill in the questionnaire.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Gabicce Mare PU 19 5781 5781
Cattolica RN 19 17125 22906
Riccione RN 19 34965 57871
Misano Adriatico RN 20 13014 70885

Municipalities with at least 50000 inhabitants

An earthquake occurred to
21 Km E of Rimini (147750 inhabitants)
25 Km NW of Pesaro (94582 inhabitants)
35 Km NW of Fano (60888 inhabitants)
46 Km E of Cesena (96758 inhabitants)
59 Km SE of Ravenna (159116 inhabitants)
63 Km E of Forlì (117913 inhabitants)
77 Km E of Faenza (58541 inhabitants)
80 Km NW of Ancona (100861 inhabitants)
91 Km E of Imola (69797 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 1.5 2021-09-20
18:21:31		 44.1278 12.8185 23 2022-03-30
13:04:30		 Bollettino Sismico Italiano INGV 99747171
Reviewed
Rev100 		ML 1.7 2021-09-20
18:21:31		 44.1403 12.7933 24 2021-09-20
18:44:35		 Sala Sismica INGV-Roma 95671611
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-20 18:21:31 ± 0.23
Latitude 44.1278 ± 0.0117
Longitude 12.8185 ± 0.0163
Depth (km) 23 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 99747171

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1229
Semi-minor axis of confidence ellipse (meter) 1043
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 62
Circular confidence region, given by single value of horizontal uncertainty (meter) 1230.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 258
Number of associated phases, regardless of their use for origin computation 21
Number of defining phases 21
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) 0.18706
Epicentral distance of station farthest from the epicenter (degree) 0.89033
Number of stations at which the event was observed 13
Number of stations from which data was used for origin computation 13
Magnitudes information

ML:1.7

Field Value
Value 1.7
Uncertainty 0.3
Num. used stations 18
Type of magnitude ML
Reference to an origin 95671611
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-20 18:44:35

ML:1.5

Field Value
Value 1.5
Uncertainty 0.3
Num. used stations 23
Type of magnitude ML
Reference to an origin 99747171
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2022-01-13 15:27:12
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.LMD.HHZ. 2021-09-20T18:21:58.71 0.3 undecidable manual S 267 88.6446 99 0.55 63
IV.ATFO.HHZ. 2021-09-20T18:21:58.34 0.3 undecidable manual S 193 86.7465 99 0.69 61
IV.ATVO.HHZ. 2021-09-20T18:21:58.48 0.3 undecidable manual S 202 89.0442 99 0.21 69
IV.FRON.EHZ. 2021-09-20T18:21:52.80 0.3 undecidable manual S 186 68.0763 102 0.04 75
IV.NARO.HHZ. 2021-09-20T18:21:50.20 0.3 undecidable manual S 198 60.3951 104 -0.56 68
IV.CPGN.EHZ. 2021-09-20T18:21:49.04 0.3 undecidable manual S 228 53.8017 106 -0.02 78
IV.MPAG.EHZ. 2021-09-20T18:21:49.15 0.3 undecidable manual S 185 55.5 105 -0.35 72
IV.MURB.HHZ. 2021-09-20T18:21:48.55 0.3 undecidable manual P 194 98.8233 98 -0.01 71
IV.ATFO.HHZ. 2021-09-20T18:21:46.80 0.3 undecidable manual P 193 86.7465 99 0.08 72
IV.ATVO.HHZ. 2021-09-20T18:21:46.88 0.1 undecidable manual P 202 89.0442 99 -0.19 94
IV.LMD.HHZ. 2021-09-20T18:21:46.78 0.3 undecidable manual P 267 88.6446 99 -0.23 70
IV.ATPI.EHZ. 2021-09-20T18:21:45.76 0.3 undecidable manual P 204 82.1511 100 -0.27 70
IV.ARVD.HHE. 2021-09-20T18:21:44.67 0.6 undecidable manual P 172 70.5738 102 0.41 47
IV.FRON.EHZ. 2021-09-20T18:21:43.97 0.1 undecidable manual P 186 68.0763 102 0.08 100
IV.COR1.HNN. 2021-09-20T18:21:42.38 1.0 undecidable manual P 165 56.8986 105 0.17 25
IV.NARO.HHZ. 2021-09-20T18:21:42.35 0.1 undecidable manual P 198 60.3951 104 -0.39 95
IV.PESA.HHZ. 2021-09-20T18:21:41.27 0.3 undecidable manual S 175 20.7681 132 0.07 82
IV.CPGN.EHZ. 2021-09-20T18:21:41.94 0.3 undecidable manual P 228 53.8017 106 0.18 75
IV.MPAG.EHZ. 2021-09-20T18:21:41.99 0.3 undecidable manual P 185 55.5 105 -0.02 77
IV.RSM2.HHZ. 2021-09-20T18:21:38.79 0.1 undecidable manual P 235 36.5412 115 -0.46 98
IV.PESA.HHZ. 2021-09-20T18:21:37.72 0.3 undecidable manual P 175 20.7681 132 0.5 75
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.PESA.HHE. ML:2.0 0.00053157615 0.0896 AML other m 2021-09-20T18:21:41.31
IV.PESA.HHN. ML:2.1 0.00060306135 0.064 AML other m 2021-09-20T18:21:41.42
IV.RSM2.HHN. ML:1.8 0.00018616015 0.384 AML other m 2021-09-20T18:21:44.28
IV.RSM2.HHE. ML:1.3 0.00006806622000000001 0.2048 AML other m 2021-09-20T18:21:44.07
IV.MPAG.EHE. ML:1.2 0.00003690741 0.1408 AML other m 2021-09-20T18:21:50.26
IV.CPGN.EHE. ML:1.3 0.000039789019999999996 0.3072 AML other m 2021-09-20T18:21:50.82
IV.CPGN.EHN. ML:1.5 0.00007279086 0.2432 AML other m 2021-09-20T18:21:51.71
IV.NARO.HHN. ML:1.3 0.00003893506 0.2304 AML other m 2021-09-20T18:21:52.63
IV.NARO.HHE. ML:1.4 0.000044376059999999994 0.1152 AML other m 2021-09-20T18:21:52.61
IV.MPAG.EHN. ML:1.5 0.00006285000000000001 0.18 AML other m 2021-09-20T18:21:52.54
IV.FRON.EHE. ML:1.3 0.000029434255 0.256 AML other m 2021-09-20T18:21:53.06
IV.FRON.EHN. ML:1.5 0.0000540563 0.2048 AML other m 2021-09-20T18:21:53.32
IV.ATVO.HHN. ML:1.3 0.000023776535 0.448 AML other m 2021-09-20T18:21:58.81
IV.ATFO.HHE. ML:1.6 0.00004815 0.92 AML other m 2021-09-20T18:21:59.76
IV.LMD.HHN. ML:1.6 0.000050537489999999994 0.2048 AML other m 2021-09-20T18:21:59.92
IV.LMD.HHE. ML:1.6 0.000047469974999999996 0.192 AML other m 2021-09-20T18:22:00.49
IV.ATPI.EHN. ML:1.2 0.000017947085000000002 0.2944 AML other m 2021-09-20T18:22:02.05
IV.ATVO.HHE. ML:1.3 0.00002431578 0.4224 AML other m 2021-09-20T18:22:02.66
IV.ATPI.EHE. ML:1.3 0.00002503451 0.2816 AML other m 2021-09-20T18:22:02.83
IV.ATFO.HHN. ML:1.5 0.000039700765 0.2432 AML other m 2021-09-20T18:22:05.68
IV.MURB.HHN. ML:2.0 0.00011185000000000001 0.3 AML other m 2021-09-20T18:22:08.57
IV.MURB.HHE. ML:2.0 0.00009992489500000002 0.32 AML other m 2021-09-20T18:22:09.13
IV.MURB.HNE. ML:2.0 0.00010946685 0.3456 AML other m 2021-09-20T18:22:10.92
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