Istituto Nazionale di Geofisica e Vulcanologia

Earthquake (quarry blast) with magnitude of ML 1.1 on date 20-05-2021 and time 17:43:13 (Italy) in region 2 km S Battifollo (CN)

A magnitude ML 1.1 (quarry blast) earthquake occured in region: 2 km S Battifollo (CN), on

  • 20-05-2021 15:43:13 (UTC)
  • 20-05-2021 17:43:13 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.3040, 8.0110 at 0 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

Event type: quarry blast.

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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Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Battifollo CN 2 219 219
Lisio CN 3 201 420
Bagnasco CN 3 1035 1455
Viola CN 4 391 1846
Scagnello CN 4 194 2040
Massimino SV 5 113 2153
Nucetto CN 6 430 2583
Monasterolo Casotto CN 6 89 2672
Priola CN 6 701 3373
Perlo CN 7 116 3489
Mombasiglio CN 8 609 4098
Pamparato CN 8 302 4400
Ceva CN 10 5782 10182
Roburent CN 10 495 10677
Torre Mondovì CN 10 498 11175
Priero CN 11 529 11704
Castelnuovo di Ceva CN 11 110 11814
Calizzano SV 11 1475 13289
San Michele Mondovì CN 12 2003 15292
Lesegno CN 12 794 16086
Montaldo di Mondovì CN 12 557 16643
Garessio CN 12 3244 19887
Sale delle Langhe CN 12 486 20373
Sale San Giovanni CN 12 183 20556
Murialdo SV 12 841 21397
Roascio CN 13 97 21494
Montezemolo CN 13 259 21753
Vicoforte CN 14 3136 24889
Castellino Tanaro CN 14 312 25201
Niella Tanaro CN 14 1046 26247
Torresina CN 15 52 26299
Briaglia CN 15 318 26617
Paroldo CN 15 211 26828
Osiglia SV 15 444 27272
Bardineto SV 16 756 28028
Monastero di Vasco CN 16 1297 29325
Igliano CN 16 74 29399
Roccavignale SV 16 752 30151
Cigliè CN 16 190 30341
Frabosa Soprana CN 16 759 31100
Rocca Cigliè CN 16 142 31242
Marsaglia CN 17 245 31487
Camerana CN 17 631 32118
Frabosa Sottana CN 17 1497 33615
Millesimo SV 17 3383 36998
Saliceto CN 18 1323 38321
Mondovì CN 18 22484 60805
Bormida SV 18 387 61192
Bastia Mondovì CN 18 669 61861
Cengio SV 18 3563 65424
Ormea CN 19 1617 67041
Murazzano CN 19 834 67875
Cosseria SV 19 1105 68980
Mombarcaro CN 19 268 69248
Plodio SV 20 650 69898
Monesiglio CN 20 645 70543
Erli SV 20 245 70788

Municipalities with at least 50000 inhabitants

An earthquake occurred to
38 Km W of Savona (61345 inhabitants)
38 Km E of Cuneo (56081 inhabitants)
57 Km NE of Sanremo (54807 inhabitants)
68 Km S of Asti (76202 inhabitants)
74 Km W of Genova (586655 inhabitants)
82 Km SE of Moncalieri (57294 inhabitants)
83 Km SW of Alessandria (93943 inhabitants)
90 Km SE of Torino (890529 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 		ML 1.1 2021-05-20
15:43:13		 44.3035 8.0112 1 2021-12-29
11:12:16		 Bollettino Sismico Italiano INGV 93580181
Reviewed
Rev100 		ML 1.2 2021-05-20
15:43:13		 44.272 8.0338 8 2021-05-20
15:50:46		 Sala Sismica INGV-Roma 90297521
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-05-20 15:43:13 ± 0.25
Latitude 44.3035 ± 0.0216
Longitude 8.0112 ± 0.0163
Depth (km) 1 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type quarry blast
Origin ID 93580181

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 2430
Semi-minor axis of confidence ellipse (meter) 1290
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 360
Circular confidence region, given by single value of horizontal uncertainty (meter) 2430.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 130
Number of associated phases, regardless of their use for origin computation 6
Number of defining phases 6
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.47
Epicentral distance of station closest to the epicenter (degree) 0.13760
Epicentral distance of station farthest from the epicenter (degree) 0.75273
Number of stations at which the event was observed 6
Number of stations from which data was used for origin computation 6
Magnitudes information

ML:1.2

Field Value
Value 1.2
Uncertainty 0.2
Num. used stations 12
Type of magnitude ML
Reference to an origin 90297521
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-05-20 15:50:46

ML:1.1

Field Value
Value 1.1
Uncertainty 0.2
Num. used stations 12
Type of magnitude ML
Reference to an origin 93580181
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-08-02 23:06:31
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
GU.BHB.HHZ. 2021-05-20T15:43:29.05 0.3 undecidable manual P 315 83.5497 50 -0.21 64
GU.ENR.HHZ. 2021-05-20T15:43:22.86 0.1 undecidable manual P 260 47.8188 91 -0.33 89
GU.IMI.HHZ. 2021-05-20T15:43:22.11 0.3 undecidable manual P 192 44.622 91 -0.44 66
IV.QLNO.HHZ. 2021-05-20T15:43:19.07 0.1 undecidable manual P 85 26.6511 91 0.12 97
GU.CANO.HHZ. 2021-05-20T15:43:17.79 0.1 undecidable manual P 121 20.868 91 0 100
GU.GBOS.HHZ. 2021-05-20T15:43:17.38 0.1 undecidable manual P 243 15.2736 92 0.71 84
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
GU.GBOS.HHE. ML:0.8 0.00007000000000000001 0.1 AML other m 2021-05-20T15:43:17.51
IV.QLNO.HHE. ML:1.2 0.0000976 0.16 AML other m 2021-05-20T15:43:19.30
GU.GBOS.HHN. ML:1.0 0.000107 0.42 AML other m 2021-05-20T15:43:19.73
GU.CANO.HHN. ML:1.4 0.00018597164999999998 0.256 AML other m 2021-05-20T15:43:20.76
IV.QLNO.HHN. ML:1.3 0.0001285 0.14 AML other m 2021-05-20T15:43:23.17
GU.ENR.HHE. ML:1.2 0.00004667685 0.1024 AML other m 2021-05-20T15:43:23.33
GU.CANO.HHE. ML:1.4 0.0001850049 0.5376 AML other m 2021-05-20T15:43:23.64
GU.IMI.HHE. ML:1.0 0.00003607722 0.2176 AML other m 2021-05-20T15:43:27.74
GU.ENR.HHN. ML:1.3 0.00005658088 0.0768 AML other m 2021-05-20T15:43:31.11
GU.IMI.HHN. ML:1.1 0.00004111151 0.192 AML other m 2021-05-20T15:43:35.49
GU.BHB.HHN. ML:0.9 0.000011202456 0.7552 AML other m 2021-05-20T15:43:55.68
GU.BHB.HHE. ML:1.1 0.00001385562 1.3984 AML other m 2021-05-20T15:43:56.93
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