Earthquake with magnitude of ML 1.1 on date 21-10-2021 and time 11:31:26 (UTC) in region 2 km SW Ussita (MC)

A magnitude ML 1.1 earthquake occured in region: 2 km SW Ussita (MC), on

  • 21-10-2021 11:31:26 (UTC)
  • 21-10-2021 13:31:26 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.931, 13.119 at 6 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
Ussita MC 2 444 444
Visso MC 2 1107 1551
Castelsantangelo sul Nera MC 5 281 1832
Preci PG 9 724 2556
Bolognola MC 11 142 2698
Monte Cavallo MC 12 145 2843
Acquacanina MC 12 121 2964
Fiordimonte MC 12 202 3166
Fiastra MC 12 559 3725
Pieve Torina MC 14 1458 5183
Pievebovigliana MC 15 866 6049
Norcia PG 16 4957 11006
Sellano PG 16 1079 12085
Montemonaco AP 17 604 12689
Muccia MC 18 915 13604
Montefortino FM 18 1178 14782
Sarnano MC 19 3264 18046

Municipalities with at least 50000 inhabitants

An earthquake occurred to
34 Km E of Foligno (57155 inhabitants)
56 Km NE of Terni (111501 inhabitants)
57 Km NW of Teramo (54892 inhabitants)
63 Km E of Perugia (166134 inhabitants)
68 Km NW of L'Aquila (69753 inhabitants)
83 Km SW of Ancona (100861 inhabitants)
96 Km W of Montesilvano (53738 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 1.1 2021-10-21
11:31:26
42.9312 13.1192 6 2021-10-21
11:37:06
Sala Sismica INGV-Roma 96842711
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-10-21 11:31:26 ± 0.21
Latitude 42.9312 ± 0.0045
Longitude 13.1192 ± 0.0074
Depth (km) 6 ± 2 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 96842711

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 600
Semi-minor axis of confidence ellipse (meter) 257
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 238
Circular confidence region, given by single value of horizontal uncertainty (meter) 600
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 113
Number of associated phases, regardless of their use for origin computation 13
Number of defining phases 13
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.2
Epicentral distance of station closest to the epicenter (degree) 0.05486
Epicentral distance of station farthest from the epicenter (degree) 0.25541
Number of stations at which the event was observed 7
Number of stations from which data was used for origin computation 7
Magnitude information

ML:1.1

Field Value
Value 1.1
Uncertainty 0.3
Num. used stations 14
Type of magnitude ML
Reference to an origin 96842711
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-10-21 11:37:06
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.MML1.EHZ. 2021-10-21T11:31:34.48 0.6 undecidable manual S 329 0.2113 105 -0.08 48
IV.CSP1.EHZ. 2021-10-21T11:31:33.13 0.6 undecidable manual S 21 0.1727 108 0.03 49
IV.CESI.HHZ. 2021-10-21T11:31:33.10 0.6 undecidable manual S 295 0.1736 108 -0.04 49
IV.MML1.EHZ. 2021-10-21T11:31:31.53 0.1 undecidable manual P 329 0.2113 105 0.54 86
IV.MF5.EHZ. 2021-10-21T11:31:31.80 0.6 undecidable manual P 77 0.2554 102 -0.14 47
IV.NRCA.HHZ. 2021-10-21T11:31:30.43 0.6 undecidable manual S 182 0.098 120 -0.03 49
IV.CESI.HHZ. 2021-10-21T11:31:30.02 0.3 positive manual P 295 0.1736 108 -0.15 71
IV.FDMO.HHZ. 2021-10-21T11:31:30.59 0.6 undecidable manual S 348 0.1079 118 -0.21 48
IV.MC2.EHZ. 2021-10-21T11:31:29.36 0.6 undecidable manual S 111 0.0549 136 0.21 48
IV.CSP1.EHZ. 2021-10-21T11:31:29.86 0.6 negative manual P 21 0.1727 108 -0.29 46
IV.FDMO.HHZ. 2021-10-21T11:31:28.71 0.6 undecidable manual P 348 0.1079 118 -0.11 49
IV.NRCA.HHZ. 2021-10-21T11:31:28.48 0.6 undecidable manual P 182 0.098 120 -0.15 48
IV.MC2.EHZ. 2021-10-21T11:31:27.89 0.1 negative manual P 111 0.0549 136 0.02 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.NRCA.HHE. ML:1.3 0.00027420315 0.0768 AML other m 2021-10-21T11:31:30.57
IV.NRCA.HHN. ML:1.1 0.00019402285 0.1216 AML other m 2021-10-21T11:31:31.58
IV.NRCA.HNE. ML:1.2 0.00024701945 0.0832 AML other m 2021-10-21T11:31:30.52
IV.NRCA.HNN. ML:1.1 0.00019345053 0.1216 AML other m 2021-10-21T11:31:31.57
IV.FDMO.HHE. ML:0.5 4.1903615E-5 0.5952 AML other m 2021-10-21T11:31:30.82
IV.FDMO.HHN. ML:0.5 4.6978585E-5 0.4416 AML other m 2021-10-21T11:31:30.90
IV.CSP1.EHE. ML:1.1 0.000109025905 0.2816 AML other m 2021-10-21T11:31:34.00
IV.CSP1.EHN. ML:1.4 0.00019200705 0.32 AML other m 2021-10-21T11:31:33.86
IV.CESI.HHE. ML:0.7 4.429849E-5 0.2368 AML other m 2021-10-21T11:31:33.22
IV.CESI.HHN. ML:1.2 0.00011989845 0.1984 AML other m 2021-10-21T11:31:33.47
IV.CESI.HNE. ML:1 7.70432E-5 0.5248 AML other m 2021-10-21T11:31:33.35
IV.CESI.HNN. ML:0.6 3.42610165E-5 0.6208 AML other m 2021-10-21T11:31:32.98
IV.MML1.EHE. ML:0.4 1.7037878E-5 0.6784 AML other m 2021-10-21T11:31:34.94
IV.MML1.EHN. ML:0.2 1.21830535E-5 0.1408 AML other m 2021-10-21T11:31:34.49
IV.MML1.HNE. ML:1.2 0.00011515775 0.8832 AML other m 2021-10-21T11:31:36.03
IV.MML1.HNN. ML:1.2 0.00010139684 1.4656 AML other m 2021-10-21T11:31:35.02
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