Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.0 on date 11-12-2020 and time 07:33:18 (Italy) in region 2 km NE Proceno (VT)

A magnitude ML 1.0 earthquake occured in region: 2 km NE Proceno (VT), on

  • 11-12-2020 06:33:18 (UTC)
  • 11-12-2020 07:33:18 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.77, 11.85 at 7 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
Proceno VT 2 557 557
Acquapendente VT 3 5506 6063
Onano VT 9 995 7058
San Lorenzo Nuovo VT 10 2091 9149
Grotte di Castro VT 11 2683 11832
Allerona TR 12 1794 13626
San Casciano dei Bagni SI 12 1632 15258
Castell'Azzara GR 12 1476 16734
Castel Giorgio TR 13 2131 18865
Castel Viscardo TR 13 2938 21803
Gradoli VT 14 1353 23156
Sorano GR 14 3428 26584
Piancastagnaio SI 16 4230 30814
Latera VT 16 836 31650
Radicofani SI 16 1097 32747
Fabro TR 17 2876 35623
Bolsena VT 18 3991 39614
Abbadia San Salvatore SI 19 6444 46058
Ficulle TR 20 1669 47727

Municipalities with at least 50000 inhabitants

An earthquake occurred to
44 Km NW of Viterbo (67173 inhabitants)
58 Km SW of Perugia (166134 inhabitants)
60 Km E of Grosseto (82087 inhabitants)
69 Km W of Terni (111501 inhabitants)
73 Km W of Foligno (57155 inhabitants)
74 Km SE of Siena (53903 inhabitants)
75 Km N of Civitavecchia (52991 inhabitants)
78 Km S of Arezzo (99543 inhabitants)
Recent and historical Seismicity
Seismic hazard
Shakemap
Felt maps
The earthquake effects in MCS scale as obtained from the compiled questionnaire

The earthquake effects in MCS scale as obtained from the compiled 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 1.0 2020-12-11
06:33:18		 42.77 11.85 7 2020-12-11
06:39:22		 Sala Sismica INGV-Roma 85351381
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2020-12-11 06:33:18 ± 0.11
Latitude 42.77 ± 0.01
Longitude 11.85 ± 0.00
Depth (km) 7 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 85351381

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 894
Semi-minor axis of confidence ellipse (meter) 223
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 341
Circular confidence region, given by single value of horizontal uncertainty (meter) 890
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 180
Number of associated phases, regardless of their use for origin computation 18
Number of defining phases 16
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.19
Epicentral distance of station closest to the epicenter (degree) 0
Epicentral distance of station farthest from the epicenter (degree) 0.56747
Number of stations at which the event was observed 10
Number of stations from which data was used for origin computation 8
Magnitude information

ML:1

Field Value
Value 1
Uncertainty 0.2
Num. used stations 10
Type of magnitude ML
Reference to an origin 85351381
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2020-12-11 06:39:22
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.GAVE.EHZ. 2020-12-11T06:33:44.93 3.0 undecidable manual S -0.03 0
IV.CAFI.HHE. 2020-12-11T06:33:38.54 0.6 undecidable manual S 9 0.5675 50 0.16 45
IV.MOMA.HHZ. 2020-12-11T06:33:37.25 0.6 undecidable manual S 86 0.5315 50 -0.07 46
IV.RIBO.EHZ.01 2020-12-11T06:33:30.34 3.0 undecidable manual P -0.12 0
IV.CAFI.HHE. 2020-12-11T06:33:29.31 0.6 undecidable manual P 9 0.5675 50 -0.52 41
IV.MOMA.HHZ. 2020-12-11T06:33:29.91 0.6 undecidable manual P 86 0.5315 50 0.69 39
IV.ARCI.HHZ. 2020-12-11T06:33:29.44 0.3 undecidable manual S 287 0.2851 102 0.08 72
IV.MGAB.HHZ. 2020-12-11T06:33:27.75 0.3 undecidable manual S 53 0.2428 104 -0.03 73
TV.SF14.HHZ. 2020-12-11T06:33:25.06 0.3 undecidable manual S 266 0.1709 110 -0.07 74
IV.ARCI.HHZ. 2020-12-11T06:33:24.45 0.6 positive manual P 287 0.2851 102 -0.17 47
IV.MCIV.CHZ. 2020-12-11T06:33:23.48 0.3 undecidable manual S 275 0.125 116 -0.03 75
TV.SF03.EHZ. 2020-12-11T06:33:23.52 0.3 undecidable manual S 287 0.1232 116 0.08 74
IV.MGAB.HHZ. 2020-12-11T06:33:23.40 0.3 undecidable manual P 53 0.2428 104 -0.31 69
IV.SACS.HHZ. 2020-12-11T06:33:22.55 0.3 undecidable manual S 30 0.0935 123 0.1 74
TV.SF14.HHZ. 2020-12-11T06:33:22.03 0.1 undecidable manual P 266 0.1709 110 -0.15 97
IV.MCIV.CHZ. 2020-12-11T06:33:21.35 0.1 positive manual P 275 0.125 116 0.1 98
TV.SF03.EHZ. 2020-12-11T06:33:21.31 0.1 undecidable manual P 287 0.1232 116 0.11 98
IV.SACS.HHZ. 2020-12-11T06:33:20.68 0.1 undecidable manual P 30 0.0935 123 0.05 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.SACS.HHN. ML:1 0.0001435 0.84 AML other m 2020-12-11T06:33:24.31
IV.MCIV.CHE. ML:0.9 9.03E-5 0.26 AML other m 2020-12-11T06:33:24.46
IV.MCIV.CHN. ML:0.8 8.13E-5 0.82 AML other m 2020-12-11T06:33:24.56
IV.MGAB.HHN. ML:1.2 8.245E-5 0.58 AML other m 2020-12-11T06:33:28.68
IV.MGAB.HHE. ML:1.1 7.33E-5 0.52 AML other m 2020-12-11T06:33:30.21
IV.SACS.HHE. ML:1 0.0001615761 0.2208 AML other m 2020-12-11T06:33:24.05
IV.SACS.HNE. ML:1.1 0.000202181095 0.2304 AML other m 2020-12-11T06:33:24.16
IV.SACS.HNN. ML:0.9 0.0001277487 0.128 AML other m 2020-12-11T06:33:24.31
IV.ARCI.HHE. ML:0.7 2.3783515E-5 0.32 AML other m 2020-12-11T06:33:29.90
IV.ARCI.HHN. ML:0.5 1.5434505E-5 0.2016 AML other m 2020-12-11T06:33:30.09
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download