Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.1 on date 28-10-2023 and time 03:50:40 (UTC) in region 2 km S Marradi (FI)

A magnitude ML 1.1 earthquake occured in region: 2 km S Marradi (FI), on

  • 28-10-2023 03:50:40 (UTC)
  • 28-10-2023 05:50:40 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.0630, 11.6180 at 5 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.

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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
Marradi FI 2 3139 3139
Palazzuolo sul Senio FI 8 1154 4293
Tredozio FC 10 1212 5505
Portico e San Benedetto FC 14 756 6261
San Godenzo FI 15 1167 7428
Premilcuore FC 16 799 8227
Modigliana FC 18 4560 12787
Casola Valsenio RA 18 2617 15404
Rocca San Casciano FC 18 1910 17314
Vicchio FI 19 8044 25358
Castel del Rio BO 19 1246 26604

Municipalities with at least 50000 inhabitants

An earthquake occurred to
33 Km SW of Faenza (58541 inhabitants)
33 Km S of Imola (69797 inhabitants)
38 Km W of Forlì (117913 inhabitants)
44 Km NE of Firenze (382808 inhabitants)
46 Km E of Prato (191150 inhabitants)
49 Km NE of Scandicci (50609 inhabitants)
51 Km W of Cesena (96758 inhabitants)
53 Km SE of Bologna (386663 inhabitants)
58 Km E of Pistoia (90315 inhabitants)
61 Km SW of Ravenna (159116 inhabitants)
70 Km NW of Arezzo (99543 inhabitants)
76 Km W of Rimini (147750 inhabitants)
85 Km SE of Modena (184973 inhabitants)
86 Km N of Siena (53903 inhabitants)
86 Km S of Ferrara (133155 inhabitants)
93 Km E of Lucca (89046 inhabitants)
99 Km SE of Carpi (70699 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 1.1 2023-10-28
03:50:40		 44.0628 11.6178 5 2023-10-28
03:59:22		 Sala Sismica INGV-Roma 122491041
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2023-10-28 03:50:40 ± 0.13
Latitude 44.0628 ± 0.0045
Longitude 11.6178 ± 0.0063
Depth (km) 5 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 122491041

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 559
Semi-minor axis of confidence ellipse (meter) 150
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 322
Circular confidence region, given by single value of horizontal uncertainty (meter) 560.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 106
Number of associated phases, regardless of their use for origin computation 30
Number of defining phases 17
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.28
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.31926
Number of stations at which the event was observed 22
Number of stations from which data was used for origin computation 10
Magnitude information

ML:1.1

Field Value
Value 1.1
Uncertainty 0.3
Num. used stations 6
Type of magnitude ML
Reference to an origin 122491041
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2023-10-28 03:59:22
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
GU.SATI.HNZ. 2023-10-28T03:52:28.13 3.0 undecidable manual Sg 14.15 0
IV.MRGE.HHZ. 2023-10-28T03:52:25.64 3.0 undecidable manual Sn 1.55 0
IV.GRI.EHZ. 2023-10-28T03:52:13.09 3.0 undecidable manual Pg 15.83 0
IV.CQUE.HHZ. 2023-10-28T03:51:59.26 3.0 undecidable manual Sg 0.55 0
IV.ECTS.HHZ. 2023-10-28T03:51:58.74 3.0 undecidable manual Pn -3.42 0
IV.MTSN.HHZ. 2023-10-28T03:51:48.82 3.0 undecidable manual Pg 11.75 0
IV.PTRP.HHZ. 2023-10-28T03:51:43.26 3.0 positive manual Pg 6.67 0
CH.MUGIO.HHZ. 2023-10-28T03:51:30.40 3.0 negative manual Pg 9.27 0
GU.SATI.HNZ. 2023-10-28T03:51:25.44 3.0 positive manual Pn -3.67 0
SL.LJU.BHZ. 2023-10-28T03:51:25.67 3.0 positive manual Pg 5.89 0
IV.PAOL.HHZ. 2023-10-28T03:51:17.48 3.0 undecidable manual Pn -3.72 0
MN.TRI.HHZ. 2023-10-28T03:51:05.86 3.0 undecidable manual Pn -6 0
IV.RUFI.EHZ. 2023-10-28T03:50:49.96 0.3 undecidable manual S 199 26.4513 102 -0.11 71
IV.SEI.HHZ. 2023-10-28T03:50:48.13 0.3 undecidable manual S 267 20.6682 105 -0.01 73
IV.MOCL.EHE. 2023-10-28T03:50:48.81 0.3 undecidable manual P 260 35.4423 99 0.91 54
IV.VISG.HHZ. 2023-10-28T03:50:48.02 0.3 undecidable manual S 314 20.2686 105 0.04 72
IT.MOG.HNN. 2023-10-28T03:50:47.30 0.3 undecidable manual S 45 16.7721 108 0.46 67
IV.VMGN.HHZ. 2023-10-28T03:50:46.30 0.3 undecidable manual S 210 13.7751 111 0.44 67
IV.RUFI.EHZ. 2023-10-28T03:50:45.78 0.1 undecidable manual P 199 26.4513 102 -0.34 90
IV.SFI.EHZ. 2023-10-28T03:50:45.46 3.0 undecidable manual S -0.04 0
IV.BOSL.HHN. 2023-10-28T03:50:45.67 0.3 undecidable manual P 233 24.3534 102 -0.04 72
IV.VISG.HHZ. 2023-10-28T03:50:44.63 0.1 undecidable manual P 314 20.2686 105 -0.28 92
IV.RINC.EHE. 2023-10-28T03:50:44.76 0.3 undecidable manual P 183 19.5693 105 -0.03 73
IV.SEI.HHZ. 2023-10-28T03:50:44.73 0.1 undecidable manual P 267 20.6682 105 -0.27 92
IT.MOG.HNN. 2023-10-28T03:50:44.20 0.1 undecidable manual P 45 16.7721 108 -0.05 97
IV.LMD.HHZ. 2023-10-28T03:50:43.81 0.1 undecidable manual S 77 7.2927 126 -0.05 98
IV.VMGN.HHZ. 2023-10-28T03:50:43.80 0.1 undecidable manual P 210 13.7751 111 0.11 96
IV.LMD.HHZ. 2023-10-28T03:50:42.44 0.1 undecidable manual P 77 7.2927 126 -0.09 98
IT.MRR.HGE. 2023-10-28T03:50:42.60 0.1 undecidable manual S 277 1.1988 168 -0.03 100
IT.MRR.HGE. 2023-10-28T03:50:41.73 0.1 undecidable manual P 277 1.1988 168 -0.09 99
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.LMD.HHN. ML:1.6 0.0007050000000000001 0.16 AML other m 2023-10-28T03:50:43.96
IV.LMD.HHE. ML:1.3 0.0003235 1.74 AML other m 2023-10-28T03:50:44.95
IV.VMGN.HHE. ML:1.0 0.00013209999999999999 0.42 AML other m 2023-10-28T03:50:46.75
IV.VMGN.HHN. ML:1.0 0.00012754999999999998 0.44 AML other m 2023-10-28T03:50:46.78
IV.VISG.HHN. ML:1.0 0.00009115 0.12 AML other m 2023-10-28T03:50:48.34
IV.SEI.HHN. ML:1.7 0.0003555 0.38 AML other m 2023-10-28T03:50:48.58
IV.SEI.HHE. ML:1.3 0.00014549999999999999 0.34 AML other m 2023-10-28T03:50:48.63
IV.VISG.HHE. ML:0.8 0.000048450000000000005 1.28 AML other m 2023-10-28T03:50:48.26
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