Earthquake with magnitude of ML 0.9 on date 19-09-2021 and time 05:16:53 (Italy) in region 4 km W Chiusdino (SI)

A magnitude ML 0.9 earthquake occured in region: 4 km W Chiusdino (SI), on

  • 19-09-2021 03:16:53 (UTC)
  • 19-09-2021 05:16:53 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.165, 11.042 at 7 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.

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 4 1903 1903
Montieri GR 4 1204 3107
Radicondoli SI 11 914 4021
Monticiano SI 12 1571 5592
Castelnuovo di Val di Cecina PI 12 2231 7823
Monterotondo Marittimo GR 15 1371 9194
Massa Marittima GR 18 8375 17569
Casole d'Elsa SI 20 3897 21466
Sovicille SI 20 10116 31582
Roccastrada GR 20 9199 40781

Municipalities with at least 50000 inhabitants

An earthquake occurred to
29 Km SW of Siena (53903 inhabitants)
45 Km N of Grosseto (82087 inhabitants)
67 Km S of Scandicci (50609 inhabitants)
70 Km S of Firenze (382808 inhabitants)
73 Km SE of Livorno (159219 inhabitants)
76 Km W of Arezzo (99543 inhabitants)
80 Km S of Prato (191150 inhabitants)
80 Km SE of Pisa (89158 inhabitants)
86 Km S of Pistoia (90315 inhabitants)
87 Km SE of Lucca (89046 inhabitants)
Recent and historical seismicity
Seismic hazard
Shakemap
Felt maps
Preliminary map of the earthquake effects from the web questionnaire

Preliminary map of the earthquake effects from the web questionnaire

This map shows the distribution of the effects of the earthquake on the territory in terms of the MCS (Mercalli-Cancani-Sieberg) intensity scale. The intensities are determined using the data provided in the questionnaire (http://www.haisentitoilterremoto.it/) that are analysed using robust statistical techniques since they are not verified individually. Specifically, the assignment of MCS intensities greater or equal the VI degree of the MCS scale require opportune in situ verification by professional experts. The purple start shows the epicenter. This map is prepared every so often that the population fill in new questionnaires. The number of questionnaires used to determine the map and the date and time of the last adjournment are shown in the upper right part of the panel.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 0.9 2021-09-19
03:16:53
43.1652 11.0418 7 2021-09-19
03:35:59
Sala Sismica INGV-Roma 95612641
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-19 03:16:53 ± 0.21
Latitude 43.1652 ± 0.0090
Longitude 11.0418 ± 0.0099
Depth (km) 7 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 95612641

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 936
Semi-minor axis of confidence ellipse (meter) 780
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 137
Circular confidence region, given by single value of horizontal uncertainty (meter) 940
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 178
Number of associated phases, regardless of their use for origin computation 7
Number of defining phases 7
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.28
Epicentral distance of station closest to the epicenter (degree) 0.09443
Epicentral distance of station farthest from the epicenter (degree) 0.3957
Number of stations at which the event was observed 4
Number of stations from which data was used for origin computation 4
Magnitude information

ML:0.9

Field Value
Value 0.9
Uncertainty 0.2
Num. used stations 4
Type of magnitude ML
Reference to an origin 95612641
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-19 03:35:59
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.CASP.HHZ. 2021-09-19T03:17:01.92 0.3 undecidable manual P 199 0.3957 50 -0.24 70
IV.RIBO.EHZ.01 2021-09-19T03:17:01.97 0.3 undecidable manual S 179 0.2158 105 -0.06 75
IV.RIBO.EHZ.01 2021-09-19T03:16:58.57 0.1 undecidable manual P 179 0.2158 105 0.19 98
IV.TRIF.CHZ. 2021-09-19T03:16:58.15 0.1 undecidable manual S 244 0.1133 118 -0.18 100
IV.FROS.CHZ. 2021-09-19T03:16:57.49 0.1 undecidable manual S 62 0.0944 122 -0.22 100
IV.FROS.CHZ. 2021-09-19T03:16:56.11 0.1 undecidable manual P 62 0.0944 122 0.22 100
IV.TRIF.CHZ. 2021-09-19T03:16:56.47 0.1 undecidable manual P 244 0.1133 118 0.22 99
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.FROS.CHE. ML:0.7 7.475E-5 1.34 AML other m 2021-09-19T03:16:57.76
IV.FROS.CHN. ML:0.7 8.035E-5 1.86 AML other m 2021-09-19T03:16:58.02
IV.TRIF.CHN. ML:0.9 0.000108 0.62 AML other m 2021-09-19T03:16:58.67
IV.TRIF.CHE. ML:1.1 0.000144 1.38 AML other m 2021-09-19T03:16:58.14
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