Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.1 on date 18-02-2021 and time 04:49:48 (Italy) in region 1 km NE Massa Martana (PG)

A magnitude ML 1.1 earthquake occured in region: 1 km NE Massa Martana (PG), on

  • 18-02-2021 03:49:48 (UTC)
  • 18-02-2021 04:49:48 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.7810, 12.5320 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
Massa Martana PG 1 3770 3770
Giano dell'Umbria PG 7 3846 7616
Acquasparta TR 10 4778 12394
Todi PG 10 16851 29245
Castel Ritaldi PG 12 3278 32523
Gualdo Cattaneo PG 15 6155 38678
Collazzone PG 15 3473 42151
Montecastrilli TR 15 5022 47173
Fratta Todina PG 16 1839 49012
Monte Castello di Vibio PG 16 1567 50579
Montefalco PG 16 5679 56258
Avigliano Umbro TR 16 2558 58816
Spoleto PG 18 38218 97034
Bevagna PG 18 5081 102115
San Gemini TR 19 5018 107133

Municipalities with at least 50000 inhabitants

An earthquake occurred to
24 Km SW of Foligno (57155 inhabitants)
26 Km NW of Terni (111501 inhabitants)
38 Km SE of Perugia (166134 inhabitants)
53 Km NE of Viterbo (67173 inhabitants)
86 Km NW of L'Aquila (69753 inhabitants)
88 Km N of Guidonia Montecelio (88673 inhabitants)
93 Km SE of Arezzo (99543 inhabitants)
93 Km N of Tivoli (56533 inhabitants)
97 Km W of Teramo (54892 inhabitants)
98 Km NE of Civitavecchia (52991 inhabitants)
99 Km N of Roma (2864731 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 1.1 2021-02-18
03:49:48		 42.7808 12.5325 8 2021-02-18
03:58:45		 Sala Sismica INGV-Roma 87265041
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-02-18 03:49:48 ± 0.08
Latitude 42.7808 ± 0.0036
Longitude 12.5325 ± 0.0061
Depth (km) 8 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 87265041

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 553
Semi-minor axis of confidence ellipse (meter) 353
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 233
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) 126
Number of associated phases, regardless of their use for origin computation 19
Number of defining phases 19
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.17
Epicentral distance of station closest to the epicenter (degree) 0.03597
Epicentral distance of station farthest from the epicenter (degree) 0.48204
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 14
Type of magnitude ML
Reference to an origin 87265041
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-02-18 03:58:45
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.MURB.HHZ. 2021-02-18T03:50:06.43 0.3 undecidable manual S 359 53.502 50 0.29 66
IV.NRCA.HHZ. 2021-02-18T03:50:04.68 0.6 undecidable manual S 83 47.7189 50 0.08 46
IV.LNSS.HHZ. 2021-02-18T03:50:04.02 0.6 undecidable manual S 115 45.9207 50 -0.09 47
IV.CESI.HHZ. 2021-02-18T03:50:02.57 0.6 undecidable manual S 50 39.1275 50 0.26 45
IV.MGAB.HHZ. 2021-02-18T03:50:01.78 0.6 undecidable manual S 293 37.1295 50 -0.01 48
IV.GAVE.EHZ. 2021-02-18T03:50:00.27 0.6 undecidable manual S 108 31.0467 105 0.32 46
IV.MURB.HHZ. 2021-02-18T03:49:59.00 1.0 undecidable manual P 359 53.502 50 0.19 22
IV.LNSS.HHZ. 2021-02-18T03:49:57.39 0.1 undecidable manual P 115 45.9207 50 -0.25 90
IV.NRCA.HHZ. 2021-02-18T03:49:57.75 0.3 negative manual P 83 47.7189 50 -0.17 68
IV.MGAB.HHZ. 2021-02-18T03:49:56.25 1.0 negative manual P 293 37.1295 50 -0.05 24
IV.CESX.HHZ. 2021-02-18T03:49:56.16 0.6 undecidable manual S 167 19.6692 113 -0.03 49
IV.CESI.HHZ. 2021-02-18T03:49:56.41 0.1 undecidable manual P 50 39.1275 50 -0.19 92
IV.ARRO.EHZ. 2021-02-18T03:49:55.36 0.6 undecidable manual P 140 29.3484 106 0.46 44
IV.GAVE.EHZ. 2021-02-18T03:49:55.05 0.6 undecidable manual P 108 31.0467 105 -0.19 47
IV.ASSB.HHZ. 2021-02-18T03:49:54.93 0.3 undecidable manual P 19 30.747 105 -0.25 69
IV.CESX.HHZ. 2021-02-18T03:49:53.27 1.0 positive manual P 167 19.6692 113 0.21 24
IV.MOMA.HHZ. 2021-02-18T03:49:51.73 0.6 undecidable manual S 50 3.996 154 -0.26 48
IV.MOMA.HHZ. 2021-02-18T03:49:50.73 0.1 undecidable manual P 50 3.996 154 0.09 100
IT.GNU.HGN. 2021-02-18T03:49:50.76 0.3 undecidable manual P 50 3.996 154 0.12 75
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.CESX.HHE. ML:1.2 0.0001325 0.64 AML other m 2021-02-18T03:49:57.78
IV.CESX.HHN. ML:1.2 0.0001245 1.04 AML other m 2021-02-18T03:49:57.42
IV.ASSB.HHE. ML:0.9 0.0000375 0.7 AML other m 2021-02-18T03:49:59.26
IV.ASSB.HHN. ML:0.8 0.00003115 0.78 AML other m 2021-02-18T03:50:00.12
IV.MGAB.HHE. ML:1.1 0.000051250000000000006 0.58 AML other m 2021-02-18T03:50:02.37
IV.MGAB.HHN. ML:1.1 0.00005025 0.52 AML other m 2021-02-18T03:50:02.62
IV.CESI.HHN. ML:0.9 0.000028200000000000004 0.42 AML other m 2021-02-18T03:50:03.85
IV.LNSS.HHN. ML:1.1 0.000037900000000000006 0.18 AML other m 2021-02-18T03:50:04.59
IV.CESI.HHE. ML:0.8 0.0000178 0.86 AML other m 2021-02-18T03:50:05.10
IV.LNSS.HHE. ML:1.1 0.00003695 0.16 AML other m 2021-02-18T03:50:05.39
IV.NRCA.HHN. ML:1.2 0.000041349999999999995 0.74 AML other m 2021-02-18T03:50:05.95
IV.NRCA.HHE. ML:1.1 0.0000348 1.24 AML other m 2021-02-18T03:50:06.63
IV.MURB.HHE. ML:1.5 0.00007905 0.34 AML other m 2021-02-18T03:50:08.33
IV.MURB.HHN. ML:1.5 0.00007425 1.7 AML other m 2021-02-18T03:50:08.91
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