Earthquake with magnitude of ML 1.6 on date 09-08-2011 and time 20:37:40 (UTC) in region 11 km SW Roccastrada (GR)

A magnitude ML 1.6 earthquake occured in region: 11 km SW Roccastrada (GR), on

  • 09-08-2011 20:37:40 (UTC)
  • 09-08-2011 22:37:40 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.9400, 11.0830 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
Roccastrada GR 11 9199 9199
Gavorrano GR 14 8580 17779
Campagnatico GR 17 2412 20191
Civitella Paganico GR 17 3154 23345
Scarlino GR 19 3847 27192
Grosseto GR 20 82087 109279

Municipalities with at least 50000 inhabitants

An earthquake occurred to
20 Km N of Grosseto (82087 inhabitants)
47 Km SW of Siena (53903 inhabitants)
87 Km SW of Arezzo (99543 inhabitants)
91 Km S of Scandicci (50609 inhabitants)
93 Km SE of Livorno (159219 inhabitants)
93 Km S of Firenze (382808 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
Md 1.7
ML 1.6
2011-08-09
20:37:40
42.94 11.083 8 2014-10-21
12:27:13
Bollettino Sismico Italiano INGV 1270349
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2011-08-09 20:37:40 ± 0.14
Latitude 42.9400 ± 0.0081
Longitude 11.0830 ± 0.0086
Depth (km) 8 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-SISPICK
Event type earthquake
Origin ID 1270349

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 765
Semi-minor axis of confidence ellipse (meter) 403
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 197
Circular confidence region, given by single value of horizontal uncertainty (meter) 1140.2
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 117
Number of associated phases, regardless of their use for origin computation 14
Number of defining phases 13
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.51
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.66820
Number of stations at which the event was observed 8
Number of stations from which data was used for origin computation 7
Magnitudes information

ML:1.6

Field Value
Value 1.6
Uncertainty 0.2
Num. used stations
Type of magnitude ML
Reference to an origin 1270349
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-06 01:04:44

Md:1.7

Field Value
Value 1.7
Uncertainty 0.2
Num. used stations
Type of magnitude Md
Reference to an origin 1270349
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-06 01:04:44
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.CELB.HHE. 2011-08-09T20:38:03.16 0.3 undecidable manual Sg 253 74.1702 -0.405 68
IV.MCIV.HHN. 2011-08-09T20:37:56.84 0.3 undecidable manual Sg 110 51.4152 -0.654 65
IV.CELB.HHE. 2011-08-09T20:37:54.52 0.3 undecidable manual Pg 253 74.1702 0.656 62
IV.ARCI.HHZ. 2011-08-09T20:37:52.25 0.1 undecidable manual Sg 107 33.3444 -0.267 100
IV.FROS.HHZ. 2011-08-09T20:37:51.16 0.3 undecidable manual Sg 11 30.4473 -0.406 73
IV.MCIV.HHN. 2011-08-09T20:37:50.90 0.3 undecidable manual Pg 110 51.4152 0.531 68
IV.TRIF.HHZ. 2011-08-09T20:37:49.08 0.3 undecidable manual Sg 323 24.2535 -0.423 74
IV.SASS.HHZ. 2011-08-09T20:37:49.80 0.3 undecidable manual Pg 318 47.5191 0.031 77
IV.CASP.HHN. 2011-08-09T20:37:49.13 0.3 undecidable manual Sg 227 24.2535 -0.359 75
IV.DGI.HHZ. 2011-08-09T20:37:49.29 10.0 undecidable manual Pg 0 0 0
IV.FROS.HHZ. 2011-08-09T20:37:47.38 0.1 undecidable manual Pg 11 30.4473 0.443 97
IV.ARCI.HHZ. 2011-08-09T20:37:47.89 0.3 undecidable manual Pg 107 33.3444 0.4 73
IV.TRIF.HHZ. 2011-08-09T20:37:45.98 0.3 undecidable manual Pg 323 24.2535 0.227 77
IV.CASP.HHN. 2011-08-09T20:37:45.98 0.3 undecidable manual Pg 227 24.2535 0.232 77
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
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QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download