Earthquake with magnitude of ML 1.9 on date 04-04-2021 and time 12:40:42 (Italy) in region 6 km NW Chiusdino (SI)

A magnitude ML 1.9 earthquake occured in region: 6 km NW Chiusdino (SI), on

  • 04-04-2021 10:40:42 (UTC)
  • 04-04-2021 12:40:42 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.1980, 11.0420 at 8 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
Chiusdino SI 6 1903 1903
Radicondoli SI 7 914 2817
Montieri GR 8 1204 4021
Castelnuovo di Val di Cecina PI 11 2231 6252
Monticiano SI 13 1571 7823
Casole d'Elsa SI 16 3897 11720
Monterotondo Marittimo GR 16 1371 13091
Pomarance PI 18 5897 18988
Sovicille SI 18 10116 29104

Municipalities with at least 50000 inhabitants

An earthquake occurred to
27 Km W of Siena (53903 inhabitants)
49 Km N of Grosseto (82087 inhabitants)
63 Km S of Scandicci (50609 inhabitants)
66 Km S of Firenze (382808 inhabitants)
71 Km SE of Livorno (159219 inhabitants)
74 Km W of Arezzo (99543 inhabitants)
76 Km S of Prato (191150 inhabitants)
77 Km SE of Pisa (89158 inhabitants)
82 Km S of Pistoia (90315 inhabitants)
84 Km SE of Lucca (89046 inhabitants)
98 Km SE of Viareggio (62467 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 2021-04-04
10:40:42
43.1985 11.0415 8 2021-07-12
16:55:13
Bollettino Sismico Italiano INGV 90574921
Reviewed
Rev100
ML 1.9 2021-04-04
10:40:42
43.2022 11.0425 8 2021-04-04
10:48:38
Sala Sismica INGV-Roma 88764471
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-04-04 10:40:42 ± 0.13
Latitude 43.1985 ± 0.0072
Longitude 11.0415 ± 0.0111
Depth (km) 8 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 90574921

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1005
Semi-minor axis of confidence ellipse (meter) 394
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 304
Circular confidence region, given by single value of horizontal uncertainty (meter) 1000.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 97
Number of associated phases, regardless of their use for origin computation 21
Number of defining phases 18
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.37
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.81748
Number of stations at which the event was observed 15
Number of stations from which data was used for origin computation 12
Magnitudes information

ML:1.9

Field Value
Value 1.9
Uncertainty 0.3
Num. used stations 11
Type of magnitude ML
Reference to an origin 90574921
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-05-28 17:03:44

ML:1.9

Field Value
Value 1.9
Uncertainty 0.3
Num. used stations 11
Type of magnitude ML
Reference to an origin 88764471
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-04-04 10:48:38
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
OX.SABO.HNZ. 2021-04-04T10:41:37.72 3.0 undecidable manual Pn 3.89 0
IV.RM33.EHZ. 2021-04-04T10:41:15.11 3.0 undecidable manual Pn 2.75 0
IV.SBPO.HNZ. 2021-04-04T10:41:12.49 3.0 positive manual Pn -0.67 0
IV.RUFI.EHE. 2021-04-04T10:41:06.65 0.3 undecidable manual S 28 80.2641 50 -0.14 65
IV.ARCI.HHZ. 2021-04-04T10:40:59.00 0.3 undecidable manual S 137 52.1034 50 -0.27 67
GU.MAIM.HHZ. 2021-04-04T10:40:58.27 0.3 undecidable manual P 331 90.7425 50 0.25 62
IV.CASP.HHZ. 2021-04-04T10:40:57.09 0.3 undecidable manual S 198 47.4192 50 -0.93 54
IV.CELB.HHZ. 2021-04-04T10:40:57.91 0.3 undecidable manual P 234 84.0492 50 0.93 50
IV.CAFI.HHZ. 2021-04-04T10:40:56.05 0.1 undecidable manual P 79 76.0683 50 0.29 85
IV.MPPT.EHN. 2021-04-04T10:40:56.66 0.3 undecidable manual P 3 84.249 50 -0.37 61
IV.RUFI.EHE. 2021-04-04T10:40:56.95 0.3 undecidable manual P 28 80.2641 50 0.54 59
TV.SF04.EHZ. 2021-04-04T10:40:54.06 0.1 undecidable manual P 129 64.3911 50 0.11 90
TV.SF14.HHZ. 2021-04-04T10:40:54.65 0.3 undecidable manual P 136 67.6767 50 0.18 66
IV.CSNT.HHZ. 2021-04-04T10:40:54.18 0.6 undecidable manual S 33 36.4413 50 -0.91 37
IV.ARCI.HHZ. 2021-04-04T10:40:52.46 0.3 undecidable manual P 137 52.1034 50 0.39 65
IV.CASP.HHZ. 2021-04-04T10:40:51.55 0.1 undecidable manual P 198 47.4192 50 0.2 91
IV.CSNT.HHZ. 2021-04-04T10:40:49.42 0.1 undecidable manual P 33 36.4413 50 -0.23 92
IV.TRIF.CHZ. 2021-04-04T10:40:47.66 0.3 undecidable manual S 230 14.5743 119 -0.36 70
IV.FROS.CHZ. 2021-04-04T10:40:46.22 0.6 undecidable manual S 82 9.3795 131 -0.31 47
IV.TRIF.CHZ. 2021-04-04T10:40:45.56 0.1 undecidable manual P 230 14.5743 119 -0.02 100
IV.FROS.CHZ. 2021-04-04T10:40:44.82 0.1 undecidable manual P 82 9.3795 131 0.11 99
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.FROS.CHE. ML:2.2 0.002575 0.24 AML other m 2021-04-04T10:40:46.32
IV.FROS.CHN. ML:2.2 0.002255 0.22 AML other m 2021-04-04T10:40:46.69
IV.TRIF.CHN. ML:2.2 0.0018050000000000002 1.42 AML other m 2021-04-04T10:40:47.15
IV.TRIF.CHE. ML:2.2 0.0017549999999999998 0.66 AML other m 2021-04-04T10:40:48.42
IV.CSNT.HHN. ML:1.7 0.0002085 0.22 AML other m 2021-04-04T10:40:54.27
IV.CSNT.HHE. ML:1.6 0.00016749999999999998 0.64 AML other m 2021-04-04T10:40:54.75
IV.CASP.HHN. ML:2.0 0.00028599999999999996 0.28 AML other m 2021-04-04T10:40:57.23
IV.CASP.HHE. ML:1.9 0.00023126389999999998 0.6592 AML other m 2021-04-04T10:40:57.25
IV.ARCI.HHE. ML:1.6 0.0001061 0.42 AML other m 2021-04-04T10:40:59.18
IV.ARCI.HNE. ML:1.8 0.00016409965 1.1008 AML other m 2021-04-04T10:40:59.39
IV.ARCI.HHN. ML:1.4 0.00006775000000000001 0.16 AML other m 2021-04-04T10:40:59.69
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