Earthquake with magnitude of ML 1.3 on date 27-10-2020 and time 21:33:43 (Italy) in region 2 km SW Castiglione d'Orcia (SI)

A magnitude ML 1.3 earthquake occured in region: 2 km SW Castiglione d'Orcia (SI), on

  • 27-10-2020 20:33:43 (UTC)
  • 27-10-2020 21:33:43 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.99, 11.6 at 12 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
Castiglione d'Orcia SI 3 2346 2346
Seggiano GR 7 961 3307
San Quirico d'Orcia SI 8 2662 5969
Castel del Piano GR 12 4690 10659
Pienza SI 12 2107 12766
Montalcino SI 12 5093 17859
Abbadia San Salvatore SI 13 6444 24303
Arcidosso GR 14 4285 28588
Radicofani SI 17 1097 29685
Piancastagnaio SI 17 4230 33915
Santa Fiora GR 17 2622 36537
San Giovanni d'Asso SI 19 853 37390
Montepulciano SI 19 14097 51487
Buonconvento SI 19 3173 54660
Cinigiano GR 20 2618 57278

Municipalities with at least 50000 inhabitants

An earthquake occurred to
43 Km SE of Siena (53903 inhabitants)
47 Km NE of Grosseto (82087 inhabitants)
58 Km SW of Arezzo (99543 inhabitants)
66 Km W of Perugia (166134 inhabitants)
76 Km NW of Viterbo (67173 inhabitants)
90 Km W of Foligno (57155 inhabitants)
91 Km SE of Firenze (382808 inhabitants)
92 Km SE of Scandicci (50609 inhabitants)
98 Km W of Terni (111501 inhabitants)
Recent and historical Seismicity
Seismic hazard
Shakemap
Felt maps
The earthquake effects in MCS scale as obtained from the compiled questionnaire

The earthquake effects in MCS scale as obtained from the compiled 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 1.3 2020-10-27
20:33:43
42.99 11.6 12 2020-10-27
21:14:31
Sala Sismica INGV-Roma 84190671
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2020-10-27 20:33:43 ± 0.15
Latitude 42.99 ± 0.01
Longitude 11.60 ± 0.01
Depth (km) 12 ± 2 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 84190671

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 825
Semi-minor axis of confidence ellipse (meter) 629
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 189
Circular confidence region, given by single value of horizontal uncertainty (meter) 830
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 156
Number of associated phases, regardless of their use for origin computation 16
Number of defining phases 16
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) 0.1322
Epicentral distance of station farthest from the epicenter (degree) 0.393
Number of stations at which the event was observed 9
Number of stations from which data was used for origin computation 9
Magnitude information

ML:1.3

Field Value
Value 1.3
Uncertainty 0.4
Num. used stations 10
Type of magnitude ML
Reference to an origin 84190671
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2020-10-27 21:14:31
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.MGAB.HHZ. 2020-10-27T20:33:56.94 0.3 undecidable manual S 101 0.3822 91 -0.24 67
IV.FROS.CHZ. 2020-10-27T20:33:51.11 0.3 undecidable manual P 305 0.393 91 -0.44 65
IV.MCIV.CHZ. 2020-10-27T20:33:51.99 0.3 undecidable manual S 165 0.2158 93 -0.27 70
IV.ARCI.HHZ. 2020-10-27T20:33:51.21 0.3 undecidable manual S 214 0.1628 97 0.5 68
IV.MGAB.HHZ. 2020-10-27T20:33:51.37 0.3 undecidable manual P 101 0.3822 91 0.01 71
TV.SF13.HHE. 2020-10-27T20:33:50.74 0.3 undecidable manual S 175 0.1691 96 -0.15 73
TV.SF04.EHZ. 2020-10-27T20:33:50.27 0.6 undecidable manual S 164 0.1574 98 -0.28 47
IV.SACS.HHZ. 2020-10-27T20:33:50.05 0.3 undecidable manual P 121 0.2653 92 0.68 63
TV.SF01.EHZ. 2020-10-27T20:33:50.90 0.3 undecidable manual S 189 0.1772 95 -0.22 71
TV.SF11.HHE. 2020-10-27T20:33:49.58 0.3 undecidable manual S 154 0.1322 105 -0.22 72
IV.MCIV.CHZ. 2020-10-27T20:33:48.62 0.1 undecidable manual P 165 0.2158 93 0.1 98
TV.SF04.EHZ. 2020-10-27T20:33:47.64 0.3 undecidable manual P 164 0.1574 98 0.11 74
TV.SF01.EHZ. 2020-10-27T20:33:47.89 0.1 undecidable manual P 189 0.1772 95 0.03 100
TV.SF11.HHE. 2020-10-27T20:33:47.40 0.1 undecidable manual P 154 0.1322 105 0.3 96
TV.SF13.HHE. 2020-10-27T20:33:47.86 0.1 undecidable manual P 175 0.1691 96 0.13 98
IV.ARCI.HHZ. 2020-10-27T20:33:47.44 0.1 undecidable manual P 214 0.1628 97 -0.19 96
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.ARCI.HHE. ML:0.9 6.093405E-5 0.192 AML other m 2020-10-27T20:33:51.78
IV.ARCI.HHN. ML:1 7.255397E-5 0.3072 AML other m 2020-10-27T20:33:51.97
TV.SF04.EHE. ML:1.8 0.00050826445 0.2432 AML other m 2020-10-27T20:33:51.39
TV.SF04.EHN. ML:1.6 0.0003417552 0.1792 AML other m 2020-10-27T20:33:51.24
TV.SF01.EHE. ML:1.5 0.0002162959 0.256 AML other m 2020-10-27T20:33:51.94
TV.SF01.EHN. ML:1.8 0.00046220215 0.2432 AML other m 2020-10-27T20:33:51.93
IV.MCIV.CHE. ML:1 5.7677315E-5 0.256 AML other m 2020-10-27T20:33:54.23
IV.MCIV.CHN. ML:1.1 7.241348E-5 0.3584 AML other m 2020-10-27T20:33:54.76
IV.MGAB.HHN. ML:1 2.8920835E-5 0.2304 AML other m 2020-10-27T20:33:58.87
IV.MGAB.HNN. ML:1.8 0.0001961132 0.576 AML other m 2020-10-27T20:33:56.12
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download