Earthquake with magnitude of Md 2.8 on date 26-04-1991 and time 03:55:08 (UTC) in region 1 km S Grugliasco (TO)

A magnitude Md 2.8 earthquake occured in region: 1 km S Grugliasco (TO), on

  • 26-04-1991 03:55:08 (UTC)
  • 26-04-1991 05:55:08 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 45.0500, 7.5750 at 10 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
Grugliasco TO 2 37966 37966
Beinasco TO 3 18159 56125
Collegno TO 3 49905 106030
Rivoli TO 4 48791 154821
Rivalta di Torino TO 4 19887 174708
Orbassano TO 6 23188 197896
Pianezza TO 6 15152 213048
Alpignano TO 6 17008 230056
Villarbasse TO 8 3509 233565
Nichelino TO 8 48123 281688
Torino TO 9 890529 1172217
Bruino TO 9 8639 1180856
Rosta TO 9 4903 1185759
Caselette TO 10 3060 1188819
Druento TO 10 8622 1197441
Sangano TO 10 3707 1201148
Candiolo TO 10 5669 1206817
Venaria Reale TO 10 34193 1241010
Moncalieri TO 10 57294 1298304
San Gillio TO 11 3174 1301478
Piossasco TO 11 18589 1320067
Buttigliera Alta TO 11 6419 1326486
Reano TO 11 1818 1328304
Volvera TO 12 8840 1337144
Vinovo TO 12 14887 1352031
Trana TO 12 3877 1355908
La Loggia TO 13 8874 1364782
Borgaro Torinese TO 13 13592 1378374
None TO 13 8005 1386379
Piobesi Torinese TO 13 3763 1390142
Givoletto TO 14 3914 1394056
Pecetto Torinese TO 14 3995 1398051
Avigliana TO 14 12516 1410567
Trofarello TO 15 11010 1421577
Caselle Torinese TO 15 19136 1440713
Val della Torre TO 15 3869 1444582
La Cassa TO 15 1788 1446370
Pino Torinese TO 16 8379 1454749
Almese TO 16 6401 1461150
San Mauro Torinese TO 16 19085 1480235
Airasca TO 16 3794 1484029
Castagnole Piemonte TO 17 2245 1486274
Robassomero TO 17 3057 1489331
Villar Dora TO 17 2932 1492263
Cumiana TO 17 7826 1500089
Giaveno TO 17 16455 1516544
Carignano TO 18 9261 1525805
Sant'Ambrogio di Torino TO 18 4755 1530560
Rubiana TO 18 2400 1532960
Cambiano TO 18 6107 1539067
Settimo Torinese TO 18 47669 1586736
Piscina TO 19 3388 1590124
Valgioie TO 19 951 1591075
Leini TO 19 16356 1607431
Scalenghe TO 19 3339 1610770
Varisella TO 19 810 1611580
Santena TO 19 10830 1622410
Fiano TO 19 2695 1625105
Baldissero Torinese TO 19 3750 1628855
San Maurizio Canavese TO 19 10237 1639092
Villastellone TO 20 4779 1643871
Chieri TO 20 36595 1680466

Municipalities with at least 50000 inhabitants

An earthquake occurred to
9 Km W of Torino (890529 inhabitants)
10 Km NW of Moncalieri (57294 inhabitants)
52 Km W of Asti (76202 inhabitants)
73 Km N of Cuneo (56081 inhabitants)
83 Km W of Alessandria (93943 inhabitants)
93 Km W of Novara (104380 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
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Bulletin
Rev1000
Md 2.8
M 3.0
1991-04-26
03:55:08
45.05 7.575 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 140049
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-04-26 03:55:08 ± 0.131
Latitude 45.0500 ± 0.0092
Longitude 7.5750 ± 0.0162
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 140049

Uncertainty

Field Value
Preferred uncertainty description horizontal uncertainty
Semi-major axis of confidence ellipse (meter)
Semi-minor axis of confidence ellipse (meter)
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi)
Circular confidence region, given by single value of horizontal uncertainty (meter) 1634.4
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 79
Number of associated phases, regardless of their use for origin computation 65
Number of defining phases 65
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.6
Epicentral distance of station closest to the epicenter (degree) 0.00219
Epicentral distance of station farthest from the epicenter (degree) 0.03545
Number of stations at which the event was observed 37
Number of stations from which data was used for origin computation 37
Magnitudes information

Md:2.8

Field Value
Value 2.8
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 140049
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:10:43

M:3.0

Field Value
Value 3.0
Uncertainty
Num. used stations
Type of magnitude M
Reference to an origin 140049
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2015-04-28 09:48:29
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.TCF.Z. 1991-04-26T03:56:52.60 10.0 undecidable manual SN 289 3.9405 -0.63 0.4
--.MAF.Z. 1991-04-26T03:56:45.80 10.0 undecidable manual SN 290 3.6852 -1.37 0.1
--.BGF.Z. 1991-04-26T03:56:45.00 10.0 undecidable manual SN 296 3.6075 -0.56 0.4
--.SSF.Z. 1991-04-26T03:56:40.60 10.0 undecidable manual SN 306 3.4632 -1.2 0.2
--.AVF.Z. 1991-04-26T03:56:39.70 10.0 undecidable manual SN 301 3.4077 -0.85 0.3
--.LOR.Z. 1991-04-26T03:56:38.70 10.0 undecidable manual SN 311 3.3855 -1.47 0.1
--.LBF.Z. 1991-04-26T03:56:35.10 10.0 undecidable manual SN 308 3.1524 0.59 0.4
--.SMF.Z. 1991-04-26T03:56:31.20 10.0 undecidable manual SN 302 3.0414 -0.73 0.4
--.HAU.Z. 1991-04-26T03:56:30.80 10.0 undecidable manual SN 344 3.0636 -1.66 0.1
--.BSF.Z. 1991-04-26T03:56:25.40 10.0 undecidable manual SN 349 2.8194 -1.36 0.2
--.PGF.Z. 1991-04-26T03:56:21.30 10.0 undecidable manual SN! 156 2.6973 -2.42 0
--.TCF.Z. 1991-04-26T03:56:10.10 10.0 undecidable manual PN 289 3.9405 0.94 0.6
--.CAF.Z. 1991-04-26T03:56:10.30 10.0 undecidable manual PN 269 3.8961 1.81 0.1
--.MAF.Z. 1991-04-26T03:56:05.60 10.0 undecidable manual PN 290 3.6852 -0.06 1.3
--.LMR.Z. 1991-04-26T03:56:05.40 10.0 undecidable manual SN 204 1.8648 1.31 0.2
--.BGF.Z. 1991-04-26T03:56:05.70 10.0 undecidable manual PN 296 3.6075 0.97 0.6
--.SSF.Z. 1991-04-26T03:56:03.39 10.0 undecidable manual PN 306 3.4632 0.83 0.8
--.LRG.Z. 1991-04-26T03:56:03.80 10.0 undecidable manual SN 208 1.8093 1.17 0.3
--.AVF.Z. 1991-04-26T03:56:02.89 10.0 undecidable manual PN 301 3.4077 1.05 0.6
--.LOR.Z. 1991-04-26T03:56:02.30 10.0 undecidable manual PN 311 3.3855 0.68 1
--.LBF.Z. 1991-04-26T03:55:59.30 10.0 undecidable manual PN 308 3.1524 0.95 0.7
--.FRF.Z. 1991-04-26T03:55:58.80 10.0 undecidable manual SN 204 1.6317 0.6 0.6
--.SMF.Z. 1991-04-26T03:55:58.00 10.0 undecidable manual PN 302 3.0414 1.14 0.6
--.HAU.Z. 1991-04-26T03:55:57.50 10.0 undecidable manual PN 344 3.0636 0.33 1.3
--.BSF.Z. 1991-04-26T03:55:54.20 10.0 undecidable manual PN 349 2.8194 0.33 1.4
--.SLE.Z. 1991-04-26T03:55:53.39 10.0 undecidable manual PN 12 2.775 0.13 1.5
--.PGF.Z. 1991-04-26T03:55:50.80 10.0 undecidable manual PN 156 2.6973 -1.32 0.4
--.OSS.Z. 1991-04-26T03:55:48.89 10.0 undecidable manual PN 46 2.4198 0.63 2.5
--.SBF.Z. 1991-04-26T03:55:45.10 10.0 undecidable manual SN! 184 1.1877 -2.65 0
--.LLS.Z. 1991-04-26T03:55:43.00 10.0 undecidable manual PN 28 2.0535 -0.22 3.4
--.VDL.Z. 1991-04-26T03:55:42.10 10.0 undecidable manual PN 41 1.9425 0.33 3.4
--.CDR.Z. 1991-04-26T03:55:42.10 10.0 undecidable manual PN 223 1.8759 1.2 0.7
--.LMR.Z. 1991-04-26T03:55:41.20 10.0 undecidable manual PN 204 1.8648 0.42 1.6
--.FIN.Z. 1991-04-26T03:55:40.39 10.0 undecidable manual SG 151 0.9546 -1.13 0.3
--.LRG.Z. 1991-04-26T03:55:40.70 10.0 undecidable manual PN 208 1.8093 0.76 1.2
--.PCP.Z. 1991-04-26T03:55:38.24 10.0 undecidable manual SG 125 0.8547 -0.09 0.7
--.FRF.Z. 1991-04-26T03:55:37.39 10.0 undecidable manual PN 204 1.6317 0 1.9
--.ROB.Z. 1991-04-26T03:55:35.66 10.0 undecidable manual SG 163 0.777 -0.15 0.7
--.ENR.Z. 1991-04-26T03:55:34.75 10.0 undecidable manual SG! 187 0.8214 -2.78 0
--.STV.Z. 1991-04-26T03:55:34.54 10.0 undecidable manual SG! 192 0.8103 -2.57 0
--.LPG.Z. 1991-04-26T03:55:32.50 10.0 undecidable manual SG 307 0.7326 -1.86 0.1
--.LPL.Z. 1991-04-26T03:55:32.50 10.0 undecidable manual SG! 308 0.7437 -2.56 0
--.EMS.Z. 1991-04-26T03:55:30.39 10.0 undecidable manual PN 336 1.11 0.09 1.9
--.SBF.Z. 1991-04-26T03:55:30.39 10.0 undecidable manual PN 184 1.1877 -0.96 1
--.BNI.Z. 1991-04-26T03:55:29.78 10.0 undecidable manual SG 270 0.6327 -1.41 0.2
--.DIX.Z. 1991-04-26T03:55:28.20 10.0 undecidable manual PN 353 1.0323 -1.02 1.8
--.DOI.Z. 1991-04-26T03:55:28.81 10.0 undecidable manual SG 203 0.5883 -1.14 0.3
--.PZZ.Z. 1991-04-26T03:55:28.90 10.0 undecidable manual SG! 211 0.6327 -2.53 0
--.MMK.Z. 1991-04-26T03:55:27.80 10.0 undecidable manual PN 14 1.0323 -1.44 0.4
--.RRL.Z. 1991-04-26T03:55:27.98 10.0 undecidable manual SG 256 0.5661 -1.33 0.2
--.FIN.Z. 1991-04-26T03:55:27.88 10.0 undecidable manual PG 151 0.9546 0.13 1.8
--.PCP.Z. 1991-04-26T03:55:26.44 10.0 undecidable manual PG 125 0.8547 0.53 1.5
--.LSD.Z. 1991-04-26T03:55:26.30 10.0 undecidable manual SG! 323 0.4995 -0.97 0
--.ROB.Z. 1991-04-26T03:55:25.10 10.0 undecidable manual PG 163 0.777 0.55 1.5
--.STV.Z. 1991-04-26T03:55:24.19 10.0 undecidable manual PG 192 0.8103 -1.02 0.9
--.ENR.Z. 1991-04-26T03:55:24.39 10.0 undecidable manual PG 187 0.8214 -1.06 0.8
--.LPL.Z. 1991-04-26T03:55:23.50 10.0 undecidable manual PG 308 0.7437 -0.53 1.5
--.LPG.Z. 1991-04-26T03:55:23.00 10.0 undecidable manual PG 307 0.7326 -0.62 1.4
--.BNI.Z. 1991-04-26T03:55:22.50 10.0 undecidable manual PG 270 0.6327 0.26 1.8
--.PZZ.Z. 1991-04-26T03:55:21.21 10.0 undecidable manual PG 211 0.6327 -0.72 1.3
--.RRL.Z. 1991-04-26T03:55:20.80 10.0 undecidable manual PG 256 0.5661 0.1 1.9
--.DOI.Z. 1991-04-26T03:55:20.63 10.0 negative manual PG 203 0.5883 -0.45 3.2
--.LSD.Z. 1991-04-26T03:55:19.68 10.0 undecidable manual PG 323 0.4995 0.3 1.7
--.RSP.Z. 1991-04-26T03:55:19.57 10.0 undecidable manual SG 294 0.2442 0.8 0.5
--.RSP.Z. 1991-04-26T03:55:15.37 10.0 undecidable manual PG 294 0.2442 0.75 1.3
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