Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 2.7 on date 20-10-2011 and time 06:14:05 (UTC) in region 4 km E Santo Stefano d'Aveto (GE)

A magnitude ML 2.7 earthquake occured in region: 4 km E Santo Stefano d'Aveto (GE), on

  • 20-10-2011 06:14:05 (UTC)
  • 20-10-2011 08:14:05 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.5540, 9.4960 at 11 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.

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Did you feel it? Fill in the questionnaire.

Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Santo Stefano d'Aveto GE 4 1126 1126
Rezzoaglio GE 9 995 2121
Ferriere PC 10 1294 3415
Bedonia PR 12 3482 6897
Tornolo PR 13 1010 7907
Compiano PR 15 1112 9019
Ottone PC 15 516 9535
Fontanigorda GE 15 277 9812
Borzonasca GE 17 2049 11861
Gorreto GE 17 97 11958
Rovegno GE 17 554 12512
Cerignale PC 18 127 12639
Farini PC 19 1290 13929
Montebruno GE 20 240 14169
Corte Brugnatella PC 20 586 14755

Municipalities with at least 50000 inhabitants

An earthquake occurred to
47 Km E of Genova (586655 inhabitants)
56 Km NW of La Spezia (93959 inhabitants)
58 Km S of Piacenza (102191 inhabitants)
71 Km NW of Carrara (63133 inhabitants)
71 Km W of Parma (192836 inhabitants)
75 Km SE of Pavia (72576 inhabitants)
77 Km SW of Cremona (71901 inhabitants)
77 Km NW of Massa (69479 inhabitants)
80 Km E of Alessandria (93943 inhabitants)
85 Km E of Savona (61345 inhabitants)
91 Km W of Reggio nell'Emilia (171345 inhabitants)
97 Km NW of Viareggio (62467 inhabitants)
99 Km SE of Vigevano (63310 inhabitants)
Recent and historical seismicity

These maps show the seismic activity in different time intervals, before the seismic event to which they refer. Data reported in the first two maps come from the analysis carried out in real time by the personnel of the INGV Operating Rooms, immediately after each earthquake. The third map shows data from 1985 to the date of the earthquake: the locations are reviewed by the seismological analysts of the INGV Italian Seismic Bulletin (Bollettino Sismico Italiano dell’INGV). The localization parameters (hypocentral coordinates and magnitude) are the best possible estimate with the data available to the INGV, but are constantly updated according to further data that become available. The location and magnitude parameters, subsequently reviewed by seismological analysts, may vary.

Earthquakes of the 3 days preceding this event

Earthquakes of the 3 days preceding this event

This map shows the earthquake epicenters with magnitude ≥ 0.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, in the 72 hours preceding this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes of the 90 days preceding this event

Earthquakes of the 90 days preceding this event

This map shows the earthquake epicenters with magnitude ≥ 2.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, in the 90 days preceding this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes from 1985 to the date of the event

Earthquakes from 1985 to the date of the event

This map shows the earthquake epicenters with magnitude ≥ 3.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, from 1985 to the date of this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes since 1000 AD until 2019

Earthquakes since 1000 AD until 2019

This map shows the epicenters of the historical earthquakes catalogue CPT15 (Catalogo Parametrico dei Terremoti Italiani, 2015 version 3.0, https://doi.org/10.13127/cpti/cpti15.3) since 1000 AD until 2019. The size of the square indicates the different classes of magnitude. For earthquakes with magnitude ≥ 6.0, it is also shown the year of occurrence and the magnitude value. The black and white star is the epicenter of the current earthquake.
Seismic hazard

Seismic hazard maps provide probabilistic estimates of the earthquake ground shaking exceeding a given threshold in a given geographic region within a given time window. Thus, it is not a deterministic prediction - a target that may be never reached given the complexity of the earthquake physical phenomenon - nor of the maximum expected earthquake since this has extremely low probabilities to occur.

In 2004, it was published the seismic hazard map of Italy (http://zonesismiche.mi.ingv.it) that provides a picture of the most hazardous geographic regions. The seismic hazard map of Italy (GdL MPS, 2004; rif. Ordinanza PCM del 28 aprile 2006, n. 3519, All. 1b) provides the 10% probability of exceedance in 50 years of the horizontal acceleration at rock sites (i.e., Vs30>800 m/s; cat. A, 3.2.1 of the D.M. 14.09.2005).

The colours indicate the various values of the ground acceleration that have 10% to be exceeded within 50 years. In general, the colours associated to low values of acceleration refer to areas that are less hazardous and stronger earthquakes repeat less frequently although they may still occur.

Seismic hazard map

Seismic hazard map

This map shows the seismic hazard map of Italy for the region where the earthquake occurred.
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
Bulletin
Rev1000 		ML 2.7 2011-10-20
06:14:05		 44.554 9.496 11 2014-10-21
12:27:13		 Bollettino Sismico Italiano INGV 1299169
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2011-10-20 06:14:05 ± 0.11
Latitude 44.5540 ± 0.0054
Longitude 9.4960 ± 0.0126
Depth (km) 11 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-SISPICK
Event type earthquake
Origin ID 1299169

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1053
Semi-minor axis of confidence ellipse (meter) 526
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 247
Circular confidence region, given by single value of horizontal uncertainty (meter) 1166.2
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 162
Number of associated phases, regardless of their use for origin computation 12
Number of defining phases 12
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.3
Epicentral distance of station closest to the epicenter (degree) 0.15199
Epicentral distance of station farthest from the epicenter (degree) 0.91641
Number of stations at which the event was observed 7
Number of stations from which data was used for origin computation 7
Magnitude information

ML:2.7

Field Value
Value 2.7
Uncertainty 0.1
Num. used stations
Type of magnitude ML
Reference to an origin 1299169
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-06 01:45:21
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
GU.PCP.HHN. 2011-10-20T06:14:28.03 0.6 undecidable manual Sg 269 75.1692 -0.213 45
IV.PLMA.HHE. 2011-10-20T06:14:25.28 0.3 undecidable manual Sg 153 62.6928 0.359 66
GU.FINB.HHE. 2011-10-20T06:14:22.91 0.3 undecidable manual Pg 246 101.7204 0.084 65
IV.QLNO.HHE. 2011-10-20T06:14:21.60 0.3 undecidable manual Pg 255 94.5387 -0.115 66
GU.PCP.HHN. 2011-10-20T06:14:19.24 0.1 undecidable manual Pg 269 75.1692 0.515 83
IV.PLMA.HHE. 2011-10-20T06:14:17.04 0.3 undecidable manual Pg 153 62.6928 0.231 68
IV.MSSA.HHZ. 2011-10-20T06:14:14.90 0.3 undecidable manual Sg 176 26.3514 -0.327 71
IV.BOB.HHZ. 2011-10-20T06:14:14.46 0.3 undecidable manual Sg 351 24.0537 -0.147 74
GU.SC2M.HHZ. 2011-10-20T06:14:12.82 0.3 undecidable manual Sg 169 16.872 0.14 75
IV.BOB.HHZ. 2011-10-20T06:14:10.86 0.3 undecidable manual Pg 351 24.0537 0.006 77
IV.MSSA.HHZ. 2011-10-20T06:14:10.89 0.1 undecidable manual Pg 176 26.3514 -0.321 95
GU.SC2M.HHZ. 2011-10-20T06:14:09.57 0.1 undecidable manual Pg 169 16.872 -0.17 100
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Fault Plane solutions

Fault Plane solutions

The map reports the fault plane solutions for earthquakes in the region from 1977 to the date of this event. Red moment tensors are determined using the Regional Centroid Moment Tensor technique (RCMT, http://www.bo.ingv.it/RCMT) applied for earthquakes with magnitude larger than 4.5 in the Euro-Mediterranenan area. Occasionally, when a station azimuthal coverage exists RCMTs can be obtained also for earthquakes with magnitude down to 4.0. The gray moment tensors are obtained with the Time Domain Moment Tensor method (TDMT, /tdmt). This technique is applied to earthquakes with magnitude ML greater than 3.2, when it is possible. The size of symbols scales with the calculated moment magnitude Mw.
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download
Waveforms Seismic signals in miniseed + resp format Download