Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.3 on date 21-09-2021 and time 23:16:39 (Italy) in region 5 km S Montieri (GR)

A magnitude ML 1.3 earthquake occured in region: 5 km S Montieri (GR), on

  • 21-09-2021 21:16:39 (UTC)
  • 21-09-2021 23:16:39 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.0840, 11.0300 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.

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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 5 1204 1204
Chiusdino SI 9 1903 3107
Massa Marittima GR 12 8375 11482
Roccastrada GR 14 9199 20681
Monticiano SI 14 1571 22252
Monterotondo Marittimo GR 16 1371 23623
Castelnuovo di Val di Cecina PI 17 2231 25854
Radicondoli SI 20 914 26768

Municipalities with at least 50000 inhabitants

An earthquake occurred to
36 Km SW of Siena (53903 inhabitants)
37 Km N of Grosseto (82087 inhabitants)
76 Km S of Scandicci (50609 inhabitants)
78 Km SE of Livorno (159219 inhabitants)
79 Km S of Firenze (382808 inhabitants)
81 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 1.3 2021-09-21
21:16:39		 43.084 11.0297 11 2022-03-30
13:04:31		 Bollettino Sismico Italiano INGV 99803911
Reviewed
Rev100 		ML 1.3 2021-09-21
21:16:39		 43.0848 11.0245 11 2021-09-21
21:23:40		 Sala Sismica INGV-Roma 95713971
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-21 21:16:39 ± 0.14
Latitude 43.0840 ± 0.0108
Longitude 11.0297 ± 0.0111
Depth (km) 11 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 99803911

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1102
Semi-minor axis of confidence ellipse (meter) 838
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 3
Circular confidence region, given by single value of horizontal uncertainty (meter) 1100.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 91
Number of associated phases, regardless of their use for origin computation 12
Number of defining phases 12
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.36
Epicentral distance of station closest to the epicenter (degree) 0.09803
Epicentral distance of station farthest from the epicenter (degree) 0.53959
Number of stations at which the event was observed 6
Number of stations from which data was used for origin computation 6
Magnitudes information

ML:1.3

Field Value
Value 1.3
Uncertainty 0.2
Num. used stations 8
Type of magnitude ML
Reference to an origin 99803911
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2022-01-15 09:40:51

ML:1.3

Field Value
Value 1.3
Uncertainty 0.3
Num. used stations 9
Type of magnitude ML
Reference to an origin 95713971
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-21 21:23:40
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
TV.SF14.HHE. 2021-09-21T21:16:57.20 0.6 undecidable manual S 127 59.8956 50 -0.52 43
IV.ARCI.HHZ. 2021-09-21T21:16:53.20 0.6 undecidable manual S 125 44.4222 50 -0.38 46
IV.MAGO.CHE. 2021-09-21T21:16:51.20 0.3 undecidable manual S 305 36.6411 50 -0.32 71
IV.CASP.HHZ. 2021-09-21T21:16:50.70 0.3 undecidable manual S 202 35.1426 50 -0.41 69
TV.SF14.HHE. 2021-09-21T21:16:50.19 0.6 undecidable manual P 127 59.8956 50 0.28 46
IV.ARCI.HHZ. 2021-09-21T21:16:47.87 0.3 undecidable manual P 125 44.4222 50 0.35 70
IV.CASP.HHZ. 2021-09-21T21:16:46.43 0.1 undecidable manual P 202 35.1426 50 0.33 96
IV.FROS.CHZ. 2021-09-21T21:16:46.00 0.3 undecidable manual S 36 17.2716 122 -0.35 73
IV.MAGO.CHE. 2021-09-21T21:16:46.78 0.3 undecidable manual P 305 36.6411 50 0.45 69
IV.TRIF.CHZ. 2021-09-21T21:16:44.10 0.3 undecidable manual S 288 10.878 135 -0.49 72
IV.FROS.CHZ. 2021-09-21T21:16:43.61 0.3 undecidable manual P 36 17.2716 122 0.26 74
IV.TRIF.CHZ. 2021-09-21T21:16:42.62 0.1 undecidable manual P 288 10.878 135 0.29 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.TRIF.CHE. ML:1.3 0.0002265 0.22 AML other m 2021-09-21T21:16:44.37
IV.TRIF.CHN. ML:1.1 0.000152 0.5 AML other m 2021-09-21T21:16:45.03
IV.FROS.CHN. ML:1.5 0.000261 0.2 AML other m 2021-09-21T21:16:46.54
IV.FROS.CHE. ML:1.4 0.000183 0.66 AML other m 2021-09-21T21:16:47.54
IV.CASP.HHE. ML:1.2 0.00006295000000000001 1.7 AML other m 2021-09-21T21:16:50.06
IV.CASP.HHN. ML:1.3 0.00008444999999999999 1.7 AML other m 2021-09-21T21:16:51.01
IV.ARCI.HHN. ML:1.1 0.000035000000000000004 0.12 AML other m 2021-09-21T21:16:53.39
IV.ARCI.HHE. ML:1.1 0.000039 1.08 AML other m 2021-09-21T21:16:53.99
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