Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.9 on date 18-09-2021 and time 08:13:09 (Italy) in region 6 km S Montieri (GR)

A magnitude ML 1.9 earthquake occured in region: 6 km S Montieri (GR), on

  • 18-09-2021 06:13:09 (UTC)
  • 18-09-2021 08:13:09 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.0800, 11.0210 at 10 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.

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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
Montieri GR 6 1204 1204
Chiusdino SI 10 1903 3107
Massa Marittima GR 11 8375 11482
Roccastrada GR 14 9199 20681
Monticiano SI 15 1571 22252
Monterotondo Marittimo GR 15 1371 23623
Castelnuovo di Val di Cecina PI 17 2231 25854
Gavorrano GR 20 8580 34434

Municipalities with at least 50000 inhabitants

An earthquake occurred to
36 Km N of Grosseto (82087 inhabitants)
37 Km SW of Siena (53903 inhabitants)
77 Km S of Scandicci (50609 inhabitants)
78 Km SE of Livorno (159219 inhabitants)
79 Km S of Firenze (382808 inhabitants)
82 Km SW of Arezzo (99543 inhabitants)
87 Km SE of Pisa (89158 inhabitants)
89 Km S of Prato (191150 inhabitants)
95 Km SE of Lucca (89046 inhabitants)
95 Km S of Pistoia (90315 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 1.9 2021-09-18
06:13:09		 43.0802 11.0212 10 2022-03-30
13:04:07		 Bollettino Sismico Italiano INGV 95691381
Reviewed
Rev100 		ML 1.9 2021-09-18
06:13:09		 43.0743 11.0283 10 2021-09-18
06:23:52		 Sala Sismica INGV-Roma 95574681
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-18 06:13:09 ± 0.13
Latitude 43.0802 ± 0.0072
Longitude 11.0212 ± 0.0123
Depth (km) 10 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 95691381

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 951
Semi-minor axis of confidence ellipse (meter) 602
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 271
Circular confidence region, given by single value of horizontal uncertainty (meter) 950.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 87
Number of associated phases, regardless of their use for origin computation 29
Number of defining phases 17
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.46
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.68079
Number of stations at which the event was observed 21
Number of stations from which data was used for origin computation 9
Magnitudes information

ML:1.9

Field Value
Value 1.9
Uncertainty 0.2
Num. used stations 14
Type of magnitude ML
Reference to an origin 95691381
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-09-21 08:50:47

ML:1.9

Field Value
Value 1.9
Uncertainty 0.2
Num. used stations 12
Type of magnitude ML
Reference to an origin 95574681
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-18 06:23:52
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
MN.PDG.HHZ. 2021-09-18T06:15:04.58 3.0 negative manual Pg 24.290001 0
IV.MCRV.HHZ. 2021-09-18T06:14:55.89 3.0 undecidable manual Sn 0.63 0
IX.SRN3.HHZ.02 2021-09-18T06:14:28.69 3.0 undecidable manual Pg 14.57 0
IV.SARZ.HHZ. 2021-09-18T06:14:24.21 3.0 undecidable manual Sg 4.78 0
IV.SLCN.HHZ. 2021-09-18T06:14:19.01 3.0 undecidable manual Pn 2.63 0
IX.PGN3.HHZ.02 2021-09-18T06:14:15.71 3.0 undecidable manual Pn -0.49 0
IV.PCN.EHZ. 2021-09-18T06:14:15.61 3.0 undecidable manual Sn 0.58 0
IX.SSB3.HHZ.02 2021-09-18T06:14:10.48 3.0 positive manual Pn 3.13 0
ST.RONC.EHZ. 2021-09-18T06:14:04.04 3.0 undecidable manual Pg 7.22 0
IV.BRSN.HNZ. 2021-09-18T06:13:56.15 3.0 undecidable manual S -0.53 0
IV.GIUL.HHZ. 2021-09-18T06:13:52.21 3.0 undecidable manual Pg 5.04 0
IV.PP3.EHZ. 2021-09-18T06:13:48.82 3.0 positive manual Pg 6.07 0
IV.OSSC.HHZ. 2021-09-18T06:13:26.62 0.1 undecidable manual S 20 52.4031 50 0.08 96
IV.CSNT.HHZ. 2021-09-18T06:13:25.04 0.3 undecidable manual S 26 48.7179 50 -0.51 66
IV.CELB.HHZ. 2021-09-18T06:13:24.08 0.1 undecidable manual P 241 75.5688 50 1.01 68
IV.ARCI.HHZ. 2021-09-18T06:13:23.79 0.3 undecidable manual S 124 44.7219 50 -0.7 62
IV.CASP.HHZ. 2021-09-18T06:13:21.12 0.3 undecidable manual S 202 34.5432 50 -0.64 64
IV.MAGO.CHZ. 2021-09-18T06:13:21.50 0.1 undecidable manual S 306 36.3414 50 -0.75 82
IV.CSNT.HHZ. 2021-09-18T06:13:19.50 0.1 undecidable manual P 26 48.7179 50 0.56 86
IV.OSSC.HHZ. 2021-09-18T06:13:19.97 0.3 undecidable manual P 20 52.4031 50 0.46 66
IV.ARCI.HHZ. 2021-09-18T06:13:18.60 0.1 negative manual P 124 44.7219 50 0.28 93
IV.MAGO.CHZ. 2021-09-18T06:13:17.25 0.1 undecidable manual P 306 36.3414 50 0.22 96
IV.CASP.HHZ. 2021-09-18T06:13:16.87 0.3 undecidable manual P 202 34.5432 50 0.12 73
IV.FROS.CHZ. 2021-09-18T06:13:16.59 0.3 undecidable manual S 37 18.0708 119 -0.51 69
IV.RIBO.EHZ.01 2021-09-18T06:13:15.88 0.1 undecidable manual S 172 14.6742 125 -0.23 99
IV.FROS.CHZ. 2021-09-18T06:13:14.22 0.1 undecidable manual P 37 18.0708 119 0.16 100
IV.TRIF.CHZ. 2021-09-18T06:13:14.58 0.1 undecidable manual S 292 10.3785 135 -0.36 97
IV.RIBO.EHZ.01 2021-09-18T06:13:13.68 0.1 positive manual P 172 14.6742 125 0.2 100
IV.TRIF.CHZ. 2021-09-18T06:13:13.05 0.1 undecidable manual P 292 10.3785 135 0.24 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.TRIF.CHE. ML:2.2 0.00196 0.24 AML other m 2021-09-18T06:13:14.63
IV.TRIF.CHN. ML:2.2 0.001935 0.24 AML other m 2021-09-18T06:13:14.64
IV.FROS.CHE. ML:2.0 0.0008425 1.4 AML other m 2021-09-18T06:13:16.01
IV.FROS.CHN. ML:2.0 0.0009145 0.4 AML other m 2021-09-18T06:13:17.00
IV.CASP.HHE. ML:2.1 0.0005385 0.34 AML other m 2021-09-18T06:13:21.53
IV.CASP.HNE. ML:2.1 0.000526 0.24 AML other m 2021-09-18T06:13:21.53
IV.CASP.HNN. ML:2.0 0.000456 0.22 AML other m 2021-09-18T06:13:21.49
IV.CASP.HHN. ML:2.0 0.00042449999999999996 0.18 AML other m 2021-09-18T06:13:21.58
IV.ARCI.HHN. ML:1.8 0.0001835 0.14 AML other m 2021-09-18T06:13:23.98
IV.ARCI.HHE. ML:1.8 0.00017099999999999998 0.92 AML other m 2021-09-18T06:13:24.98
IV.OSSC.HHE. ML:1.4 0.00005665 0.48 AML other m 2021-09-18T06:13:27.53
IV.OSSC.HHN. ML:1.2 0.000039 1.26 AML other m 2021-09-18T06:13:28.26
IV.CELB.HHN. ML:1.8 0.00008790000000000001 0.46 AML other m 2021-09-18T06:13:35.08
IV.CELB.HHE. ML:1.8 0.00010700000000000001 0.44 AML other m 2021-09-18T06:13:35.23
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