Earthquake with magnitude of ML 0.6 on date 18-09-2021 and time 22:39:23 (Italy) in region 6 km S Montieri (GR)

A magnitude ML 0.6 earthquake occured in region: 6 km S Montieri (GR), on

  • 18-09-2021 20:39:23 (UTC)
  • 18-09-2021 22:39:23 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.078, 11.013 at 10 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
Montieri GR 6 1204 1204
Massa Marittima GR 11 8375 9579
Chiusdino SI 11 1903 11482
Roccastrada GR 15 9199 20681
Monterotondo Marittimo GR 15 1371 22052
Monticiano SI 15 1571 23623
Castelnuovo di Val di Cecina PI 17 2231 25854
Gavorrano GR 19 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)
83 Km SW of Arezzo (99543 inhabitants)
86 Km SE of Pisa (89158 inhabitants)
90 Km S of Prato (191150 inhabitants)
95 Km SE of Lucca (89046 inhabitants)
96 Km S of Pistoia (90315 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 earthquake resentment in the area, expressed in terms of intensity on the MCS scale (Mercalli-Cancani-Sieberg). Intensities are determined using data from questionnaires collected on the website http://www.hsit.it. The intensities shown are determined considering all the reports received from each municipality, and are all the more reliable the greater the number of questionnaires. The collected data are subjected to an automatic statistical filter, but are not checked individually. In particular, intensities greater than or equal to the VI degree of the MCS or EMS scale require on-site verification by specialized personnel. The black star is the epicenter of the earthquake that occurred. This map is updated every time citizens fill out new questionnaires. The number of questionnaires processed to obtain this map, the date and time of the last update are shown at the top right.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 0.6 2021-09-18
20:39:23
43.0782 11.0127 11 2021-09-18
20:43:45
Sala Sismica INGV-Roma 95600791
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-18 20:39:23 ± 0.18
Latitude 43.0782 ± 0.0090
Longitude 11.0127 ± 0.0148
Depth (km) 11 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 95600791

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1095
Semi-minor axis of confidence ellipse (meter) 971
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 81
Circular confidence region, given by single value of horizontal uncertainty (meter) 1100
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 131
Number of associated phases, regardless of their use for origin computation 8
Number of defining phases 8
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.34
Epicentral distance of station closest to the epicenter (degree) 0.08813
Epicentral distance of station farthest from the epicenter (degree) 0.30667
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:0.6

Field Value
Value 0.6
Uncertainty 0.1
Num. used stations 2
Type of magnitude ML
Reference to an origin 95600791
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-09-18 20:43:45
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.CASP.HHZ. 2021-09-18T20:39:35.15 0.3 undecidable manual S 201 0.3067 50 -0.41 68
IV.FROS.CHZ. 2021-09-18T20:39:30.91 0.6 undecidable manual S 38 0.1682 119 -0.39 47
IV.CASP.HHZ. 2021-09-18T20:39:30.93 0.3 undecidable manual P 201 0.3067 50 0.31 70
IV.RIBO.EHZ.01 2021-09-18T20:39:29.91 0.6 undecidable manual S 169 0.1313 126 -0.2 49
IV.TRIF.CHZ. 2021-09-18T20:39:28.53 0.3 undecidable manual S 295 0.0881 137 -0.32 72
IV.FROS.CHZ. 2021-09-18T20:39:28.24 0.1 undecidable manual P 38 0.1682 119 0.08 100
IV.RIBO.EHZ.01 2021-09-18T20:39:27.66 0.1 undecidable manual P 169 0.1313 126 0.18 99
IV.TRIF.CHZ. 2021-09-18T20:39:27.07 0.1 undecidable manual P 295 0.0881 137 0.32 97
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.TRIF.CHN. ML:0.6 4.53E-5 0.44 AML other m 2021-09-18T20:39:29.13
IV.TRIF.CHE. ML:0.6 5.435E-5 0.16 AML other m 2021-09-18T20:39:29.83
IV.FIR.HHE. ML:2.2 0.000244 0.06 AML other m 2021-09-18T20:39:42.92
IV.FIR.HHN. ML:2.3 0.000252 1.36 AML other m 2021-09-18T20:39:55.98
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