Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.1 on date 04-12-2020 and time 22:05:10 (UTC) in region 4 km NE Castel Ritaldi (PG)

A magnitude ML 1.1 earthquake occured in region: 4 km NE Castel Ritaldi (PG), on

  • 04-12-2020 22:05:10 (UTC)
  • 04-12-2020 23:05:10 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.85, 12.7 at 10 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
Castel Ritaldi PG 4 3278 3278
Trevi PG 5 8469 11747
Montefalco PG 6 5679 17426
Campello sul Clitunno PG 7 2442 19868
Giano dell'Umbria PG 10 3846 23714
Foligno PG 11 57155 80869
Bevagna PG 12 5081 85950
Gualdo Cattaneo PG 13 6155 92105
Spoleto PG 14 38218 130323
Spello PG 16 8645 138968
Vallo di Nera PG 16 364 139332
Massa Martana PG 17 3770 143102
Sant'Anatolia di Narco PG 18 564 143666
Cerreto di Spoleto PG 18 1075 144741
Cannara PG 18 4305 149046
Scheggino PG 19 461 149507
Sellano PG 19 1079 150586

Municipalities with at least 50000 inhabitants

An earthquake occurred to
11 Km S of Foligno (57155 inhabitants)
33 Km N of Terni (111501 inhabitants)
38 Km SE of Perugia (166134 inhabitants)
69 Km NE of Viterbo (67173 inhabitants)
80 Km NW of L'Aquila (69753 inhabitants)
85 Km W of Teramo (54892 inhabitants)
95 Km N of Guidonia Montecelio (88673 inhabitants)
95 Km SE of Arezzo (99543 inhabitants)
99 Km N of Tivoli (56533 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 1.1 2020-12-04
22:05:10		 42.85 12.7 10 2020-12-04
22:18:27		 Sala Sismica INGV-Roma 85203411
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2020-12-04 22:05:10 ± 0.06
Latitude 42.85 ± 0.01
Longitude 12.70 ± 0.01
Depth (km) 10 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 85203411

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 991
Semi-minor axis of confidence ellipse (meter) 339
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 302
Circular confidence region, given by single value of horizontal uncertainty (meter) 990
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 109
Number of associated phases, regardless of their use for origin computation 22
Number of defining phases 22
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.25
Epicentral distance of station closest to the epicenter (degree) 0.10702
Epicentral distance of station farthest from the epicenter (degree) 0.43977
Number of stations at which the event was observed 11
Number of stations from which data was used for origin computation 11
Magnitude information

ML:1.1

Field Value
Value 1.1
Uncertainty 0.2
Num. used stations 8
Type of magnitude ML
Reference to an origin 85203411
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2020-12-04 22:18:27
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.CSP1.EHZ. 2020-12-04T22:05:26.94 0.3 undecidable manual S 57 0.4398 50 0.27 68
IV.LNSS.HHE. 2020-12-04T22:05:24.17 0.3 undecidable manual S 135 0.3552 50 0.02 73
IV.FDMO.HHZ. 2020-12-04T22:05:23.12 0.6 undecidable manual S 57 0.3381 50 -0.53 43
IT.MTCL.HGE. 2020-12-04T22:05:21.03 0.3 undecidable manual S 57 0.2608 50 -0.33 69
IV.ARRO.EHE. 2020-12-04T22:05:21.99 0.3 undecidable manual S 170 0.2788 50 0.09 73
IV.CSP1.EHZ. 2020-12-04T22:05:20.37 0.1 undecidable manual P 57 0.4398 50 0.37 89
IV.CESX.HHE. 2020-12-04T22:05:20.70 0.3 undecidable manual S 199 0.259 50 -0.6 64
IV.CESI.HHZ. 2020-12-04T22:05:19.55 0.3 undecidable manual S 45 0.2131 112 -0.23 71
IV.LNSS.HHE. 2020-12-04T22:05:18.34 0.1 undecidable manual P 135 0.3552 50 -0.2 93
IV.FDMO.HHZ. 2020-12-04T22:05:18.22 0.3 undecidable manual P 57 0.3381 50 -0.04 73
IV.ASSB.HHZ. 2020-12-04T22:05:18.75 0.3 undecidable manual S 351 0.1907 115 -0.23 72
IT.MTCL.HGE. 2020-12-04T22:05:17.43 0.1 undecidable manual P 57 0.2608 50 0.49 89
IV.ARRO.EHE. 2020-12-04T22:05:17.44 0.6 undecidable manual P 170 0.2788 50 0.19 47
IV.CESX.HHE. 2020-12-04T22:05:17.08 0.6 undecidable manual P 199 0.259 50 0.18 48
IT.FOPC.HGN. 2020-12-04T22:05:16.46 0.3 undecidable manual S 2 0.116 127 -0.03 76
IV.MOMA.HHZ. 2020-12-04T22:05:16.05 0.3 undecidable manual S 242 0.107 130 -0.17 74
IT.GNU.HGZ. 2020-12-04T22:05:16.08 0.3 undecidable manual S 242 0.107 130 -0.14 74
IV.ASSB.HHZ. 2020-12-04T22:05:15.58 0.1 undecidable manual P 351 0.1907 115 0.02 100
IV.CESI.HHZ. 2020-12-04T22:05:15.94 0.1 undecidable manual P 45 0.2131 112 -0.08 98
IV.MOMA.HHZ. 2020-12-04T22:05:14.20 0.1 undecidable manual P 242 0.107 130 0.24 97
IT.GNU.HGZ. 2020-12-04T22:05:14.20 0.1 undecidable manual P 242 0.107 130 0.24 97
IT.FOPC.HGN. 2020-12-04T22:05:14.21 0.1 undecidable manual P 2 0.116 127 0.09 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.MOMA.HHN. ML:1.3 0.0002195 0.3 AML other m 2020-12-04T22:05:16.48
IV.MOMA.HHE. ML:1.5 0.0003615 0.14 AML other m 2020-12-04T22:05:16.73
IV.ASSB.HHE. ML:1.1 8.4388835E-5 0.1536 AML other m 2020-12-04T22:05:19.25
IV.ASSB.HHN. ML:1.1 8.1743805E-5 0.1664 AML other m 2020-12-04T22:05:19.29
IV.CESI.HHE. ML:0.8 3.91462395E-5 0.1024 AML other m 2020-12-04T22:05:20.08
IV.CESI.HHN. ML:1.1 8.0204E-5 0.1792 AML other m 2020-12-04T22:05:21.63
IV.FDMO.HHE. ML:1 3.365302E-5 0.1536 AML other m 2020-12-04T22:05:25.52
IV.FDMO.HHN. ML:1 3.485937E-5 0.256 AML other m 2020-12-04T22:05:23.92
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