Earthquake with magnitude of ML 0.8 on date 18-04-2021 and time 18:37:11 (Italy) in region 4 km SE Accumoli (RI)

A magnitude ML 0.8 earthquake occured in region: 4 km SE Accumoli (RI), on

  • 18-04-2021 16:37:11 (UTC)
  • 18-04-2021 18:37:11 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.677, 13.285 at 11 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

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
Accumoli RI 4 667 667
Amatrice RI 5 2657 3324
Arquata del Tronto AP 11 1178 4502
Cittareale RI 12 482 4984
Acquasanta Terme AP 15 2916 7900
Campotosto AQ 15 542 8442
Montereale AQ 17 2581 11023
Capitignano AQ 17 665 11688
Valle Castellana TE 19 977 12665
Montegallo AP 19 523 13188
Cortino TE 19 656 13844
Rocca Santa Maria TE 20 537 14381

Municipalities with at least 50000 inhabitants

An earthquake occurred to
34 Km W of Teramo (54892 inhabitants)
37 Km N of L'Aquila (69753 inhabitants)
54 Km E of Terni (111501 inhabitants)
57 Km SE of Foligno (57155 inhabitants)
73 Km W of Montesilvano (53738 inhabitants)
80 Km W of Pescara (121014 inhabitants)
81 Km W of Chieti (51815 inhabitants)
87 Km SE of Perugia (166134 inhabitants)
88 Km NE of Guidonia Montecelio (88673 inhabitants)
89 Km NE of Tivoli (56533 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
Bulletin
Rev1000
ML 0.8 2021-04-18
16:37:11
42.6773 13.2853 11 2021-07-12
16:55:12
Bollettino Sismico Italiano INGV 90287811
Reviewed
Rev100
ML 1.1 2021-04-18
16:37:09
42.5573 13.1702 10 2021-04-18
16:41:57
Sala Sismica INGV-Roma 89218981
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-04-18 16:37:11 ± 0.04
Latitude 42.6773 ± 0.0027
Longitude 13.2853 ± 0.0037
Depth (km) 11 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 90287811

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 311
Semi-minor axis of confidence ellipse (meter) 278
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 101
Circular confidence region, given by single value of horizontal uncertainty (meter) 310
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 57
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) 0.15
Epicentral distance of station closest to the epicenter (degree) 0.04317
Epicentral distance of station farthest from the epicenter (degree) 0.30847
Number of stations at which the event was observed 11
Number of stations from which data was used for origin computation 11
Magnitudes information

ML:0.8

Field Value
Value 0.8
Uncertainty 0.2
Num. used stations 4
Type of magnitude ML
Reference to an origin 90287811
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-05-20 08:42:15

ML:1.1

Field Value
Value 1.1
Uncertainty 0.3
Num. used stations 6
Type of magnitude ML
Reference to an origin 89218981
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-04-18 16:41:57
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.GIGS.HHN. 2021-04-18T16:37:22.41 0.6 undecidable manual S 137 0.3085 50 -0.22 46
IV.GAVE.HNZ. 2021-04-18T16:37:22.25 0.6 undecidable manual S 273 0.2878 50 0.23 47
IV.MC2.EHZ. 2021-04-18T16:37:21.05 0.6 undecidable manual S 343 0.2446 50 0.32 46
IV.MMO1.EHN. 2021-04-18T16:37:20.10 0.6 undecidable manual S 8 0.2239 50 -0.03 49
IV.TERO.HHZ. 2021-04-18T16:37:20.58 0.6 undecidable manual S 103 0.2401 50 -0.04 49
IV.NRCA.HHZ. 2021-04-18T16:37:19.19 0.6 undecidable manual S 321 0.2005 50 -0.24 47
IV.LNSS.HNZ. 2021-04-18T16:37:19.12 0.3 undecidable manual S 248 0.1952 50 -0.15 72
IV.RM33.HNZ. 2021-04-18T16:37:18.64 0.3 undecidable manual S 197 0.1763 50 -0.08 74
IV.GAVE.HNZ. 2021-04-18T16:37:17.18 0.1 undecidable manual P 273 0.2878 50 -0.19 94
IV.GIGS.HHN. 2021-04-18T16:37:17.70 0.6 undecidable manual P 137 0.3085 50 -0.02 48
IV.MTRA.HNZ. 2021-04-18T16:37:16.55 0.3 undecidable manual S 46 0.1133 131 -0.28 71
IV.MC2.EHZ. 2021-04-18T16:37:16.59 0.3 undecidable manual P 343 0.2446 50 -0.04 73
IV.MMO1.EHN. 2021-04-18T16:37:16.35 0.6 undecidable manual P 8 0.2239 50 0.07 49
IV.TERO.HHZ. 2021-04-18T16:37:16.74 0.3 undecidable manual P 103 0.2401 50 0.18 71
IV.SMA1.EHZ. 2021-04-18T16:37:15.37 0.3 undecidable manual S 142 0.0594 149 -0.1 75
IV.T1299.HNZ. 2021-04-18T16:37:15.08 0.1 undecidable manual S 183 0.0432 156 -0.11 100
IV.RM33.HNZ. 2021-04-18T16:37:15.67 0.3 undecidable manual P 197 0.1763 50 0.21 72
IV.NRCA.HHZ. 2021-04-18T16:37:15.88 0.1 positive manual P 321 0.2005 50 0 99
IV.LNSS.HNZ. 2021-04-18T16:37:15.76 0.3 undecidable manual P 248 0.1952 50 -0.02 74
IV.MTRA.HNZ. 2021-04-18T16:37:14.47 0.3 undecidable manual P 46 0.1133 131 0.09 74
IV.SMA1.EHZ. 2021-04-18T16:37:13.80 0.3 undecidable manual P 142 0.0594 149 0.21 73
IV.T1299.HNZ. 2021-04-18T16:37:13.66 0.1 undecidable manual P 183 0.0432 156 0.24 97
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.SMA1.EHN. ML:1 0.0001455 0.2 AML other m 2021-04-18T16:37:15.52
IV.SMA1.EHE. ML:1 0.000154 0.1 AML other m 2021-04-18T16:37:15.62
IV.NRCA.HHN. ML:1 6.805E-5 0.16 AML other m 2021-04-18T16:37:19.26
IV.NRCA.HHE. ML:1.3 0.00012 0.16 AML other m 2021-04-18T16:37:19.36
IV.TERO.HHN. ML:0.7 2.585E-5 1.1 AML other m 2021-04-18T16:37:21.28
IV.TERO.HHE. ML:0.6 2.115E-5 1.1 AML other m 2021-04-18T16:37:21.31
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