Earthquake with magnitude of ML 1.8 on date 20-10-2021 and time 16:15:46 (UTC) in region 6 km W Forlì (FC)

A magnitude ML 1.8 earthquake occured in region: 6 km W Forlì (FC), on

  • 20-10-2021 16:15:46 (UTC)
  • 20-10-2021 18:15:46 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.237, 11.968 at 24 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
Forlì FC 6 117913 117913
Castrocaro Terme e Terra del Sole FC 7 6426 124339
Faenza RA 9 58541 182880
Forlimpopoli FC 14 13290 196170
Dovadola FC 14 1653 197823
Meldola FC 14 9970 207793
Predappio FC 15 6346 214139
Brisighella RA 16 7639 221778
Russi RA 16 12247 234025
Castel Bolognese RA 16 9554 243579
Bertinoro FC 17 11059 254638
Modigliana FC 17 4560 259198
Cotignola RA 17 7474 266672
Solarolo RA 17 4488 271160
Riolo Terme RA 20 5720 276880
Bagnacavallo RA 20 16739 293619

Municipalities with at least 50000 inhabitants

An earthquake occurred to
6 Km W of Forlì (117913 inhabitants)
9 Km SE of Faenza (58541 inhabitants)
24 Km SE of Imola (69797 inhabitants)
25 Km W of Cesena (96758 inhabitants)
27 Km SW of Ravenna (159116 inhabitants)
52 Km W of Rimini (147750 inhabitants)
57 Km E of Bologna (386663 inhabitants)
72 Km SE of Ferrara (133155 inhabitants)
77 Km NE of Firenze (382808 inhabitants)
80 Km E of Prato (191150 inhabitants)
82 Km NE of Scandicci (50609 inhabitants)
84 Km W of Pesaro (94582 inhabitants)
86 Km N of Arezzo (99543 inhabitants)
90 Km E of Pistoia (90315 inhabitants)
94 Km S of Rovigo (51867 inhabitants)
94 Km E of Modena (184973 inhabitants)
95 Km W of Fano (60888 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 1.8 2021-10-20
16:15:46
44.2368 11.9678 24 2021-10-20
16:27:52
Sala Sismica INGV-Roma 96804861
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-10-20 16:15:46 ± 0.28
Latitude 44.2368 ± 0.0099
Longitude 11.9678 ± 0.0113
Depth (km) 24 ± 2 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 96804861

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 951
Semi-minor axis of confidence ellipse (meter) 648
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 120
Circular confidence region, given by single value of horizontal uncertainty (meter) 950
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 155
Number of associated phases, regardless of their use for origin computation 38
Number of defining phases 18
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.33
Epicentral distance of station closest to the epicenter (degree) 0
Epicentral distance of station farthest from the epicenter (degree) 0.61783
Number of stations at which the event was observed 29
Number of stations from which data was used for origin computation 9
Magnitude information

ML:1.8

Field Value
Value 1.8
Uncertainty 0.3
Num. used stations 18
Type of magnitude ML
Reference to an origin 96804861
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-10-20 16:27:52
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.SERS.HHZ. 2021-10-20T16:17:32.74 3.0 undecidable manual Pg 14.9 0
IV.SCIAC.HHZ. 2021-10-20T16:17:27.32 3.0 undecidable manual Pn 3.03 0
IT.GLNS.HNZ. 2021-10-20T16:17:23.57 3.0 undecidable manual Sg 10.28 0
GU.MGRO.HHZ. 2021-10-20T16:17:23.82 3.0 undecidable manual Sg 12.1 0
IV.TREM.HHZ. 2021-10-20T16:17:21.46 3.0 undecidable manual Sn 3.79 0
IX.PGN3.HHZ.02 2021-10-20T16:17:07.34 3.0 undecidable manual Pg 12.19 0
IX.RSF3.HHZ.02 2021-10-20T16:16:55.63 3.0 undecidable manual Pg 8.65 0
IV.PTCC.HHZ. 2021-10-20T16:16:53.66 3.0 undecidable manual Sn -4.66 0
IV.SGAL.EHZ. 2021-10-20T16:16:44.65 3.0 undecidable manual Sg 1.05 0
IV.ZEN8.EHZ. 2021-10-20T16:16:38.90 3.0 undecidable manual Sg -1.94 0
IV.VIVA.HHZ. 2021-10-20T16:16:32.30 3.0 negative manual Pg 5.85 0
CH.FUORN.HHZ. 2021-10-20T16:16:31.40 3.0 positive manual Pn 0.45 0
IV.EUCT.HNZ. 2021-10-20T16:16:25.53 3.0 positive manual Pn 0.99 0
IV.ARVD.HHZ. 2021-10-20T16:16:22.06 3.0 undecidable manual S 2.44 0
IV.CADC.HNZ. 2021-10-20T16:16:22.52 3.0 negative manual Pg 3.87 0
IV.SRES.HHZ. 2021-10-20T16:16:19.33 3.0 undecidable manual Pn -0.03 0
IV.MSSA.HHZ. 2021-10-20T16:16:18.68 3.0 negative manual Pg 1.2 0
IV.PP3.EHZ. 2021-10-20T16:16:10.95 3.0 negative manual Pn -1.02 0
IV.RIBO.EHZ.01 2021-10-20T16:16:09.45 3.0 undecidable manual Pn -2.2 0
IV.CRE.HHZ. 2021-10-20T16:16:08.00 0.6 undecidable manual S 181 0.6178 103 0.78 36
IV.RUFI.EHZ. 2021-10-20T16:16:04.64 0.3 undecidable manual S 220 0.5171 106 0.31 66
IV.SEI.HHZ. 2021-10-20T16:16:03.42 0.3 undecidable manual S 248 0.4739 108 0.32 67
IV.ASQU.HHZ. 2021-10-20T16:16:02.91 0.3 undecidable manual S 196 0.4587 108 0.24 68
IV.VISG.HHZ. 2021-10-20T16:16:01.26 0.6 undecidable manual S 263 0.3849 112 0.62 42
IV.SFI.EHZ. 2021-10-20T16:15:59.20 0.6 undecidable manual S 195 0.3435 115 -0.3 46
IV.CRE.HHZ. 2021-10-20T16:15:58.27 0.1 undecidable manual P 181 0.6178 103 0 92
IV.LMD.HHZ. 2021-10-20T16:15:56.40 0.6 undecidable manual S 230 0.2455 125 -0.6 43
IV.RUFI.EHZ. 2021-10-20T16:15:56.34 0.6 negative manual P 220 0.5171 106 -0.27 45
IV.SEI.HHZ. 2021-10-20T16:15:55.78 0.6 positive manual P 248 0.4739 108 -0.11 46
IV.ASQU.HHZ. 2021-10-20T16:15:55.32 1.0 negative manual P 196 0.4587 108 -0.33 22
IV.PE3.EHZ. 2021-10-20T16:15:55.57 3.0 negative manual P -2.7 0
IV.BRSN.EHZ. 2021-10-20T16:15:54.76 0.3 undecidable manual S 60 0.0935 154 0.74 62
IV.BRIS.HHZ. 2021-10-20T16:15:54.54 0.3 undecidable manual S 265 0.1448 142 -0.29 72
IV.VISG.HHZ. 2021-10-20T16:15:54.69 0.3 positive manual P 263 0.3849 112 0.22 70
IV.SFI.EHZ. 2021-10-20T16:15:53.33 0.1 undecidable manual P 195 0.3435 115 -0.49 88
IV.LMD.HHZ. 2021-10-20T16:15:51.86 1.0 negative manual P 230 0.2455 125 -0.51 22
IV.BRIS.HHZ. 2021-10-20T16:15:50.80 0.1 positive manual P 265 0.1448 142 -0.32 95
IV.BRSN.EHZ. 2021-10-20T16:15:50.51 0.1 negative manual P 60 0.0935 154 -0.14 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.BRIS.HHE. ML:2.4 0.00135 0.3 AML other m 2021-10-20T16:15:54.68
IV.BRIS.HHN. ML:2.2 0.0009015 1.64 AML other m 2021-10-20T16:15:55.82
IV.BRSN.HNN. ML:2.3 0.00123 0.58 AML other m 2021-10-20T16:15:55.01
IV.BRSN.EHN. ML:2.3 0.0012 0.58 AML other m 2021-10-20T16:15:55.01
IV.BRSN.EHE. ML:2.2 0.0010785 0.24 AML other m 2021-10-20T16:15:55.55
IV.BRSN.HNE. ML:2.3 0.0012585 0.32 AML other m 2021-10-20T16:15:55.55
IV.SFI.EHN. ML:1.8 0.0001885 0.94 AML other m 2021-10-20T16:15:59.91
IV.SFI.EHE. ML:1.8 0.0002065 0.4 AML other m 2021-10-20T16:16:00.25
IV.VISG.HHE. ML:1.4 6.47E-5 1.34 AML other m 2021-10-20T16:16:02.94
IV.VISG.HHN. ML:1.5 9.22E-5 0.24 AML other m 2021-10-20T16:16:02.33
IV.ASQU.HHE. ML:1.6 0.0001015 0.42 AML other m 2021-10-20T16:16:03.38
IV.SEI.HHN. ML:2.1 0.000295 1.78 AML other m 2021-10-20T16:16:05.01
IV.ASQU.HHN. ML:1.7 0.00010335 1.74 AML other m 2021-10-20T16:16:05.03
IV.SEI.HHE. ML:1.8 0.000134 0.28 AML other m 2021-10-20T16:16:05.77
IV.CRE.HHN. ML:1.6 7.08E-5 0.4 AML other m 2021-10-20T16:16:09.37
IV.CRE.HHE. ML:1.4 4.32E-5 1.52 AML other m 2021-10-20T16:16:09.77
IV.RUFI.EHE. ML:1.4 4.69964E-5 0.3584 AML other m 2021-10-20T16:16:04.58
IV.RUFI.EHN. ML:1.4 5.2125765E-5 0.4096 AML other m 2021-10-20T16:16:06.36
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