Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.0 on date 21-08-2020 and time 21:22:40 (UTC) in region 1 km SW Amatrice (RI)

A magnitude ML 1.0 earthquake occured in region: 1 km SW Amatrice (RI), on

  • 21-08-2020 21:22:40 (UTC)
  • 21-08-2020 23:22:40 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.6200, 13.2830 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
Amatrice RI 1 2657 2657
Accumoli RI 9 667 3324
Campotosto AQ 10 542 3866
Cittareale RI 10 482 4348
Montereale AQ 11 2581 6929
Capitignano AQ 11 665 7594
Arquata del Tronto AP 17 1178 8772
Borbona RI 17 617 9389
Crognaleto TE 18 1297 10686
Cagnano Amiterno AQ 18 1369 12055
Cortino TE 19 656 12711
Posta RI 19 694 13405
Barete AQ 19 737 14142
Acquasanta Terme AP 20 2916 17058

Municipalities with at least 50000 inhabitants

An earthquake occurred to
31 Km NW of L'Aquila (69753 inhabitants)
35 Km W of Teramo (54892 inhabitants)
52 Km E of Terni (111501 inhabitants)
60 Km SE of Foligno (57155 inhabitants)
72 Km W of Montesilvano (53738 inhabitants)
78 Km W of Pescara (121014 inhabitants)
79 Km W of Chieti (51815 inhabitants)
83 Km NE of Guidonia Montecelio (88673 inhabitants)
83 Km NE of Tivoli (56533 inhabitants)
91 Km SE of Perugia (166134 inhabitants)
99 Km E of Viterbo (67173 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 2020-08-21
21:22:40		 42.6203 13.2827 10 2020-08-21
21:38:59		 Sala Sismica INGV-Roma 82214051
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2020-08-21 21:22:40 ± 0.08
Latitude 42.6203 ± 0.0054
Longitude 13.2827 ± 0.0061
Depth (km) 10 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 82214051

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 551
Semi-minor axis of confidence ellipse (meter) 499
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 174
Circular confidence region, given by single value of horizontal uncertainty (meter) 550.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 76
Number of associated phases, regardless of their use for origin computation 27
Number of defining phases 19
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) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.29857
Number of stations at which the event was observed 18
Number of stations from which data was used for origin computation 10
Magnitude information

ML:1.0

Field Value
Value 1.0
Uncertainty 0.4
Num. used stations 9
Type of magnitude ML
Reference to an origin 82214051
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2020-08-21 21:38:59
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.HPAC.HHZ. 2020-08-21T21:23:58.35 3.0 negative manual Pn 3.11 0
IV.MBAL.EHZ. 2020-08-21T21:23:46.33 3.0 negative manual Pg 19.15 0
IV.FIR.HHZ. 2020-08-21T21:23:43.31 3.0 undecidable manual Sn 6.71 0
XK.SELL.HHZ. 2020-08-21T21:23:34.95 3.0 undecidable manual Pg 5.46 0
IV.CSNT.HHZ. 2020-08-21T21:23:31.25 3.0 undecidable manual Sn -1.86 0
IV.PESA.HHZ. 2020-08-21T21:23:16.42 3.0 undecidable manual Sn -0.54 0
IV.FOSV.EHZ. 2020-08-21T21:23:16.28 3.0 undecidable manual Sg 8.8 0
IV.MMO1.HNN. 2020-08-21T21:22:51.41 0.6 undecidable manual S 7 31.1466 50 0.2 47
IV.GIGS.HHE. 2020-08-21T21:22:50.66 0.6 undecidable manual S 128 30.1476 50 -0.26 47
IV.TERO.HHE. 2020-08-21T21:22:49.79 0.6 undecidable manual S 89 26.2515 110 -0.03 50
IV.NRCA.HHZ. 2020-08-21T21:22:49.93 0.6 undecidable manual S 330 27.3504 50 -0.25 47
IV.MC2.EHZ. 2020-08-21T21:22:47.26 1.0 undecidable manual P 347 33.1446 50 0.43 23
IV.LNSS.HHZ. 2020-08-21T21:22:47.69 0.6 undecidable manual S 265 19.869 116 -0.1 49
IV.MTRA.HNN. 2020-08-21T21:22:47.29 0.6 undecidable manual S 31 17.7711 119 0.15 49
IV.GIGS.HHE. 2020-08-21T21:22:46.38 0.1 undecidable manual P 128 30.1476 50 0.03 99
IV.NRCA.HHZ. 2020-08-21T21:22:46.01 0.3 negative manual P 330 27.3504 50 0.08 74
IV.MMO1.HNN. 2020-08-21T21:22:46.08 0.1 undecidable manual P 7 31.1466 50 -0.44 90
IV.TERO.HHE. 2020-08-21T21:22:45.77 0.1 undecidable manual P 89 26.2515 110 0.05 99
IV.RM33.EHZ. 2020-08-21T21:22:45.92 0.6 undecidable manual S 204 13.5753 126 0.03 51
IV.LNSS.HHZ. 2020-08-21T21:22:44.84 0.1 undecidable manual P 265 19.869 116 0.29 95
IV.MTRA.HNN. 2020-08-21T21:22:44.48 0.1 undecidable manual P 31 17.7711 119 0.31 95
IV.RM33.EHZ. 2020-08-21T21:22:43.60 0.6 undecidable manual P 204 13.5753 126 0.15 50
IV.SMA1.EHZ. 2020-08-21T21:22:43.71 0.6 undecidable manual S 75 4.3956 155 -0.1 51
IV.SMA1.EHZ. 2020-08-21T21:22:42.53 0.1 positive manual P 75 4.3956 155 0.28 98
IV.T1299.EHE. 2020-08-21T21:22:42.63 0.6 undecidable manual S 359 1.5984 171 -0.89 40
IV.ROSPO.HHZ. 2020-08-21T21:22:41.97 3.0 undecidable manual P -0.51 0
IV.T1299.EHE. 2020-08-21T21:22:41.88 0.1 undecidable manual P 359 1.5984 171 -0.2 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.SMA1.EHN. ML:1.2 0.0002685 0.28 AML other m 2020-08-21T21:22:43.77
IV.SMA1.EHE. ML:1.2 0.0002515 0.32 AML other m 2020-08-21T21:22:44.31
IV.RM33.EHN. ML:0.6 0.00003875 1.22 AML other m 2020-08-21T21:22:46.18
IV.RM33.EHE. ML:0.5 0.00003235000000000001 0.58 AML other m 2020-08-21T21:22:46.60
IV.NRCA.HHN. ML:0.7 0.0000235 0.1 AML other m 2020-08-21T21:22:50.44
IV.NRCA.HHE. ML:0.6 0.000018950000000000003 0.72 AML other m 2020-08-21T21:22:50.40
IV.RM33.HNE. ML:1.1 0.000139999255 0.7808 AML other m 2020-08-21T21:22:53.57
IV.NRCA.HNE. ML:1.4 0.00012031054999999999 0.448 AML other m 2020-08-21T21:22:51.31
IV.NRCA.HNN. ML:1.4 0.00013693715 0.6784 AML other m 2020-08-21T21:22:54.50
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