Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.0 on date 23-10-2021 and time 19:24:36 (UTC) in region 2 km SW Ussita (MC)

A magnitude ML 1.0 earthquake occured in region: 2 km SW Ussita (MC), on

  • 23-10-2021 19:24:36 (UTC)
  • 23-10-2021 21:24:36 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.9310, 13.1230 at 8 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
Ussita MC 2 444 444
Visso MC 3 1107 1551
Castelsantangelo sul Nera MC 5 281 1832
Preci PG 9 724 2556
Bolognola MC 11 142 2698
Acquacanina MC 12 121 2819
Fiastra MC 12 559 3378
Fiordimonte MC 12 202 3580
Monte Cavallo MC 12 145 3725
Pieve Torina MC 14 1458 5183
Pievebovigliana MC 15 866 6049
Norcia PG 16 4957 11006
Sellano PG 17 1079 12085
Montemonaco AP 17 604 12689
Montefortino FM 18 1178 13867
Muccia MC 18 915 14782
Sarnano MC 19 3264 18046
Amandola FM 20 3629 21675
Montegallo AP 20 523 22198

Municipalities with at least 50000 inhabitants

An earthquake occurred to
34 Km E of Foligno (57155 inhabitants)
56 Km NW of Teramo (54892 inhabitants)
57 Km NE of Terni (111501 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
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100 		ML 1.0 2021-10-23
19:24:36		 42.9313 13.1232 8 2021-10-23
19:39:25		 Sala Sismica INGV-Roma 96915361
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-10-23 19:24:36 ± 0.08
Latitude 42.9313 ± 0.0027
Longitude 13.1232 ± 0.0037
Depth (km) 8 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 96915361

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 360
Semi-minor axis of confidence ellipse (meter) 137
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) 360.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 111
Number of associated phases, regardless of their use for origin computation 32
Number of defining phases 23
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.22
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 21
Number of stations from which data was used for origin computation 12
Magnitude information

ML:1.0

Field Value
Value 1.0
Uncertainty 0.3
Num. used stations 10
Type of magnitude ML
Reference to an origin 96915361
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-10-23 19:39:25
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IX.STN3.HNZ.01 2021-10-23T19:25:49.47 3.0 undecidable manual Sn -6.14 0
IV.ESCV.HHZ. 2021-10-23T19:25:46.03 3.0 positive manual Pn -5.89 0
IV.PII.HHZ. 2021-10-23T19:25:42.80 3.0 undecidable manual Sg 4.76 0
OT.OT17.EHZ. 2021-10-23T19:25:31.85 3.0 undecidable manual Sg 0.63 0
IV.RIBO.EHZ.01 2021-10-23T19:25:21.30 3.0 undecidable manual Sn -3.77 0
IX.SCL3.EHZ.02 2021-10-23T19:25:19.54 3.0 undecidable manual Pg 2.33 0
IV.GIUL.HHZ. 2021-10-23T19:25:17.42 3.0 undecidable manual Sg 0.81 0
IV.PAOL.HHZ. 2021-10-23T19:25:02.79 3.0 undecidable manual Pn -5.38 0
IV.VIVA.HHZ. 2021-10-23T19:24:54.83 3.0 positive manual Pg -1.53 0
IV.T1299.EHZ. 2021-10-23T19:24:48.71 0.3 undecidable manual S 158 35.4423 50 0 72
IV.MF5.EHZ. 2021-10-23T19:24:46.97 0.3 undecidable manual S 77 28.0497 106 0.67 62
IV.GUMA.HHZ. 2021-10-23T19:24:44.78 0.3 undecidable manual S 50 22.5552 110 0.29 70
IV.PF6.EHZ. 2021-10-23T19:24:44.42 0.3 undecidable manual S 14 23.6541 109 -0.42 68
IV.T1299.EHZ. 2021-10-23T19:24:43.23 0.1 undecidable manual P 158 35.4423 50 -0.19 93
IV.CSP1.EHZ. 2021-10-23T19:24:43.12 0.3 undecidable manual S 20 18.9699 113 -0.22 71
IV.CESI.HHZ. 2021-10-23T19:24:43.73 0.3 undecidable manual S 295 19.5693 113 0.22 71
IV.MF5.EHZ. 2021-10-23T19:24:42.14 0.3 undecidable manual P 77 28.0497 106 0.13 71
IV.MMO1.HNZ. 2021-10-23T19:24:42.50 0.3 undecidable manual S 102 16.9719 116 -0.19 72
IV.MML1.EHZ. 2021-10-23T19:24:41.67 0.3 undecidable manual P 329 23.6541 109 0.49 67
IV.GUMA.HHZ. 2021-10-23T19:24:41.08 0.1 undecidable manual P 50 22.5552 110 0.11 96
IV.FDMO.HHZ. 2021-10-23T19:24:41.01 0.3 undecidable manual S 346 12.0768 124 -0.2 72
IV.PF6.EHZ. 2021-10-23T19:24:40.94 0.1 undecidable manual P 14 23.6541 109 -0.24 94
IV.NRCA.HHZ. 2021-10-23T19:24:40.71 0.3 undecidable manual S 184 10.878 127 -0.17 73
IV.CSP1.EHZ. 2021-10-23T19:24:40.19 0.1 undecidable manual P 20 18.9699 113 -0.12 97
IV.CESI.HHZ. 2021-10-23T19:24:40.41 0.1 undecidable manual P 295 19.5693 113 0 99
IV.FDMO.HHZ. 2021-10-23T19:24:39.05 0.1 undecidable manual P 346 12.0768 124 -0.03 100
IV.FEMA.HNZ. 2021-10-23T19:24:39.88 0.3 undecidable manual S 300 6.8931 140 0.01 76
IV.MC2.EHZ. 2021-10-23T19:24:39.55 0.3 undecidable manual S 112 5.7942 145 -0.09 75
IV.MMO1.HNZ. 2021-10-23T19:24:39.82 0.1 undecidable manual P 102 16.9719 116 -0.11 97
IV.FEMA.HNZ. 2021-10-23T19:24:38.48 0.1 undecidable manual P 300 6.8931 140 0.17 98
IV.MC2.EHZ. 2021-10-23T19:24:38.24 0.1 undecidable manual P 112 5.7942 145 0.07 100
IV.NRCA.HHZ. 2021-10-23T19:24:38.92 0.1 undecidable manual P 184 10.878 127 0.03 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.NRCA.HHE. ML:1.3 0.00027249630000000005 0.064 AML other m 2021-10-23T19:24:40.83
IV.FDMO.HHN. ML:0.5 0.000038855185 0.1536 AML other m 2021-10-23T19:24:41.28
IV.NRCA.HHN. ML:1.1 0.000153265985 0.0768 AML other m 2021-10-23T19:24:41.40
IV.FDMO.HHE. ML:0.5 0.000038128045 0.1792 AML other m 2021-10-23T19:24:41.23
IV.CESI.HHN. ML:1.1 0.00010170000000000002 0.14 AML other m 2021-10-23T19:24:43.89
IV.CESI.HHE. ML:0.8 0.0000532 0.44 AML other m 2021-10-23T19:24:44.00
IV.NRCA.HNE. ML:1.3 0.0002513253 0.0768 AML other m 2021-10-23T19:24:40.94
IV.NRCA.HNN. ML:1.0 0.00013494210000000002 0.064 AML other m 2021-10-23T19:24:41.40
IV.CSP1.EHE. ML:1.0 0.00008698099000000001 0.2176 AML other m 2021-10-23T19:24:44.38
IV.CSP1.EHN. ML:1.2 0.0001196453 0.3072 AML other m 2021-10-23T19:24:44.80
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