Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.4 on date 31-10-2021 and time 03:35:11 (UTC) in region 5 km SE Roma (RM)

A magnitude ML 1.4 earthquake occured in region: 5 km SE Roma (RM), on

  • 31-10-2021 03:35:11 (UTC)
  • 31-10-2021 04:35:11 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 41.8610, 12.5220 at 9 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
Roma RM 5 2864731 2864731
Ciampino RM 9 38412 2903143
Grottaferrata RM 15 20327 2923470
Frascati RM 15 22087 2945557
Marino RM 15 43026 2988583
Castel Gandolfo RM 17 8997 2997580
Monte Porzio Catone RM 17 8693 3006273
Fonte Nuova RM 17 32562 3038835
Albano Laziale RM 19 41715 3080550
Monte Compatri RM 19 11978 3092528
Rocca di Papa RM 19 17034 3109562
Colonna RM 19 4287 3113849
Ariccia RM 20 19407 3133256

Municipalities with at least 50000 inhabitants

An earthquake occurred to
5 Km SE of Roma (2864731 inhabitants)
21 Km N of Pomezia (62966 inhabitants)
23 Km SW of Guidonia Montecelio (88673 inhabitants)
26 Km E of Fiumicino (78395 inhabitants)
26 Km W of Tivoli (56533 inhabitants)
29 Km NW of Velletri (53303 inhabitants)
31 Km NW of Aprilia (73446 inhabitants)
47 Km N of Anzio (54211 inhabitants)
54 Km NW of Latina (125985 inhabitants)
66 Km E of Civitavecchia (52991 inhabitants)
71 Km SE of Viterbo (67173 inhabitants)
79 Km S of Terni (111501 inhabitants)
91 Km SW of L'Aquila (69753 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 1.4 2021-10-31
03:35:11		 41.8612 12.5223 9 2022-03-30
13:04:38		 Bollettino Sismico Italiano INGV 101080321
Reviewed
Rev100 		ML 1.4 2021-10-31
03:35:11		 41.8563 12.5127 9 2021-10-31
03:46:04		 Sala Sismica INGV-Roma 97103721
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-10-31 03:35:11 ± 0.06
Latitude 41.8612 ± 0.0036
Longitude 12.5223 ± 0.0048
Depth (km) 9 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 101080321

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 536
Semi-minor axis of confidence ellipse (meter) 246
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 221
Circular confidence region, given by single value of horizontal uncertainty (meter) 540.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 129
Number of associated phases, regardless of their use for origin computation 27
Number of defining phases 27
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.17
Epicentral distance of station closest to the epicenter (degree) 0.03327
Epicentral distance of station farthest from the epicenter (degree) 0.62413
Number of stations at which the event was observed 15
Number of stations from which data was used for origin computation 15
Magnitudes information

ML:1.4

Field Value
Value 1.4
Uncertainty 0.4
Num. used stations 8
Type of magnitude ML
Reference to an origin 97103721
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-10-31 03:46:04

ML:1.4

Field Value
Value 1.4
Uncertainty 0.5
Num. used stations 12
Type of magnitude ML
Reference to an origin 101080321
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2022-02-17 12:01:37
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.GIUL.HHZ. 2021-10-31T03:35:33.44 0.6 undecidable manual S 119 69.2751 50 0.38 42
IV.BARO.EHN. 2021-10-31T03:35:30.53 0.6 undecidable manual S 318 57.8976 50 0.54 41
IV.SRES.HHZ. 2021-10-31T03:35:25.74 0.6 undecidable manual S 359 41.7249 50 0.05 47
IV.CERT.HNE. 2021-10-31T03:35:25.39 0.6 undecidable manual S 75 39.1275 50 0.38 44
IV.RCAV.EHZ. 2021-10-31T03:35:24.00 0.6 undecidable manual S 92 34.9428 50 0.11 47
IV.FIAM.HNN. 2021-10-31T03:35:23.37 0.6 undecidable manual P 47 66.5778 50 -0.25 43
IV.GIUL.HHZ. 2021-10-31T03:35:23.61 0.3 undecidable manual P 119 69.2751 50 -0.43 63
IV.BARO.EHN. 2021-10-31T03:35:22.16 0.3 undecidable manual P 318 57.8976 50 -0.11 68
IV.MTCE.HHZ. 2021-10-31T03:35:21.09 0.6 undecidable manual S 45 25.5522 110 -0.06 49
IV.VIVA.HHZ. 2021-10-31T03:35:20.97 0.6 undecidable manual S 121 23.8539 111 0.35 46
IV.RDP.HHZ. 2021-10-31T03:35:19.24 0.6 undecidable manual S 126 19.1697 116 0.13 49
IV.SRES.HHZ. 2021-10-31T03:35:19.73 0.3 undecidable manual P 359 41.7249 50 -0.05 71
IV.CERT.HNE. 2021-10-31T03:35:19.16 0.3 undecidable manual P 75 39.1275 50 -0.23 69
IV.RMP.HHZ. 2021-10-31T03:35:18.18 0.6 undecidable manual S 110 16.0728 120 0.02 50
IV.RCAV.EHZ. 2021-10-31T03:35:18.48 0.3 undecidable manual P 92 34.9428 50 -0.26 69
IV.MTCE.HHZ. 2021-10-31T03:35:17.01 0.3 undecidable manual P 45 25.5522 110 -0.15 72
IV.MA9.HHE. 2021-10-31T03:35:17.90 0.6 undecidable manual S 132 15.1737 122 0 50
IV.RDP.HHZ. 2021-10-31T03:35:16.02 0.3 undecidable manual P 126 19.1697 116 0.04 74
IV.VIVA.HHZ. 2021-10-31T03:35:16.99 0.3 undecidable manual P 121 23.8539 111 0.13 72
IV.LAV9.HHN. 2021-10-31T03:35:16.91 0.3 undecidable manual P 144 25.0527 111 -0.16 72
IT.RMMM.HGN. 2021-10-31T03:35:16.15 0.6 undecidable manual S 320 8.9799 136 -0.06 50
IV.RMP.HHZ. 2021-10-31T03:35:15.50 0.3 undecidable manual P 110 16.0728 120 0.06 74
IV.ROM9.HNE. 2021-10-31T03:35:15.28 0.6 undecidable manual S 189 3.6963 159 0.08 50
IV.MA9.HHE. 2021-10-31T03:35:15.22 0.3 undecidable manual P 132 15.1737 122 -0.07 74
IT.RMMM.HGN. 2021-10-31T03:35:14.61 0.3 undecidable manual P 320 8.9799 136 0.3 72
IV.SAMA.EHZ. 2021-10-31T03:35:14.54 0.6 undecidable manual P 147 10.6782 131 -0.01 50
IV.ROM9.HNE. 2021-10-31T03:35:13.61 0.1 undecidable manual P 189 3.6963 159 -0.12 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.RMP.HHN. ML:2.0 0.0008694935999999999 0.1808 AML other m 2021-10-31T03:35:19.15
IV.RMP.HHE. ML:2.1 0.0012799999999999999 0.1 AML other m 2021-10-31T03:35:19.34
IV.RDP.HHN. ML:1.4 0.00020248345 0.12 AML other m 2021-10-31T03:35:19.70
IV.RDP.HHE. ML:1.2 0.000141365 0.16 AML other m 2021-10-31T03:35:20.77
IV.VIVA.HHN. ML:2.2 0.0009015 0.24 AML other m 2021-10-31T03:35:21.37
IV.MTCE.HHE. ML:0.7 0.000030796315 0.1392 AML other m 2021-10-31T03:35:21.00
IV.VIVA.HHE. ML:2.2 0.0010371340500000001 0.3008 AML other m 2021-10-31T03:35:22.13
IV.MTCE.HHN. ML:0.7 0.000028642874999999998 0.08 AML other m 2021-10-31T03:35:22.87
IV.RCAV.EHN. ML:1.5 0.00012599872000000002 0.12 AML other m 2021-10-31T03:35:24.91
IV.RCAV.EHE. ML:1.5 0.00013300275 0.1184 AML other m 2021-10-31T03:35:25.50
IV.GIUL.HHN. ML:1.0 0.000016683570000000002 0.1808 AML other m 2021-10-31T03:35:34.35
IV.GIUL.HHE. ML:1.0 0.000012751657499999999 0.3392 AML other m 2021-10-31T03:35:36.56
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