Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of Md 3.2 on date 25-07-1993 and time 18:47:47 (UTC) in region 4 km NW Rialto (SV)

A magnitude Md 3.2 earthquake occured in region: 4 km NW Rialto (SV), on

  • 25-07-1993 18:47:47 (UTC)
  • 25-07-1993 20:47:47 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.2420, 8.2360 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.

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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
Rialto SV 4 564 564
Bormida SV 4 387 951
Osiglia SV 5 444 1395
Magliolo SV 6 974 2369
Calice Ligure SV 6 1730 4099
Mallare SV 8 1146 5245
Orco Feglino SV 8 890 6135
Tovo San Giacomo SV 8 2582 8717
Giustenice SV 8 977 9694
Calizzano SV 10 1475 11169
Bardineto SV 10 756 11925
Pallare SV 10 923 12848
Vezzi Portio SV 10 809 13657
Murialdo SV 10 841 14498
Borgio Verezzi SV 11 2205 16703
Pietra Ligure SV 11 8992 25695
Finale Ligure SV 12 11711 37406
Boissano SV 12 2492 39898
Loano SV 13 11407 51305
Toirano SV 13 2644 53949
Plodio SV 13 650 54599
Altare SV 14 2108 56707
Carcare SV 14 5587 62294
Balestrino SV 14 595 62889
Roccavignale SV 14 752 63641
Millesimo SV 14 3383 67024
Borghetto Santo Spirito SV 14 4948 71972
Cosseria SV 14 1105 73077
Massimino SV 15 113 73190
Spotorno SV 15 3803 76993
Castelnuovo di Ceva CN 15 110 77103
Noli SV 15 2736 79839
Quiliano SV 15 7232 87071
Erli SV 16 245 87316
Castelvecchio di Rocca Barbena SV 16 145 87461
Perlo CN 16 116 87577
Ceriale SV 16 5561 93138
Vado Ligure SV 16 8336 101474
Cengio SV 16 3563 105037
Bergeggi SV 17 1129 106166
Bagnasco CN 17 1035 107201
Priola CN 17 701 107902
Montezemolo CN 17 259 108161
Garessio CN 17 3244 111405
Zuccarello SV 17 309 111714
Nucetto CN 18 430 112144
Cairo Montenotte SV 18 13269 125413
Cisano sul Neva SV 19 2085 127498
Priero CN 19 529 128027
Castelbianco SV 19 330 128357
Saliceto CN 20 1323 129680
Battifollo CN 20 219 129899

Municipalities with at least 50000 inhabitants

An earthquake occurred to
21 Km W of Savona (61345 inhabitants)
57 Km E of Cuneo (56081 inhabitants)
59 Km W of Genova (586655 inhabitants)
59 Km NE of Sanremo (54807 inhabitants)
73 Km S of Asti (76202 inhabitants)
81 Km SW of Alessandria (93943 inhabitants)
95 Km SE of Moncalieri (57294 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 3.2
M 2.8 		1993-07-25
18:47:47		 44.242 8.236 10 2013-07-15
08:40:51		 Bollettino Sismico Italiano INGV 192179
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1993-07-25 18:47:47 ± 0.205
Latitude 44.2420 ± 0.0123
Longitude 8.2360 ± 0.0184
Depth (km) 10 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 192179

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) 2005.2
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 125
Number of associated phases, regardless of their use for origin computation 40
Number of defining phases 40
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.4
Epicentral distance of station closest to the epicenter (degree) 0.00032
Epicentral distance of station farthest from the epicenter (degree) 0.01603
Number of stations at which the event was observed 21
Number of stations from which data was used for origin computation 21
Magnitudes information

Md:3.2

Field Value
Value 3.2
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 192179
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 20:00:34

M:2.8

Field Value
Value 2.8
Uncertainty
Num. used stations
Type of magnitude M
Reference to an origin 192179
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
--.LPL.Z. 1993-07-25T18:48:40.40 10.0 undecidable manual SN! 320 1.6539 2.52 0
--.LPG.Z. 1993-07-25T18:48:39.79 10.0 undecidable manual SN! 320 1.6317 2.45 0
--.LRG.Z. 1993-07-25T18:48:38.29 10.0 undecidable manual SN! 240 1.554 2.7 0
--.LSD.Z. 1993-07-25T18:48:33.10 10.0 undecidable manual SN 328 1.4319 0.55 0.5
--.FRF.Z. 1993-07-25T18:48:31.10 10.0 undecidable manual SN 239 1.332 1.04 0.2
--.BNI.Z. 1993-07-25T18:48:31.88 10.0 undecidable manual SN 306 1.3653 0.86 0.3
--.RRL.Z. 1993-07-25T18:48:27.40 10.0 undecidable manual SN 303 1.2321 -0.4 0.6
--.RSP.Z. 1993-07-25T18:48:24.30 10.0 undecidable manual SN 322 1.1433 -1.32 0.1
--.LPL.Z. 1993-07-25T18:48:19.00 10.0 undecidable manual PN! 320 1.6539 2.24 0
--.LPG.Z. 1993-07-25T18:48:18.80 10.0 undecidable manual PN! 320 1.6317 2.35 0
--.BHB.Z. 1993-07-25T18:48:17.94 10.0 undecidable manual SG 310 0.9102 -1.15 0.2
--.LRG.Z. 1993-07-25T18:48:17.80 10.0 undecidable manual PN! 240 1.554 2.36 0
--.PGF.Z. 1993-07-25T18:48:17.50 10.0 undecidable manual PN 161 1.776 -0.92 0.5
--.PZZ.Z. 1993-07-25T18:48:16.40 10.0 undecidable manual SG 288 0.8436 -0.79 0.4
--.LSD.Z. 1993-07-25T18:48:14.48 10.0 undecidable manual PN 328 1.4319 0.79 0.8
--.LMR.Z. 1993-07-25T18:48:14.90 10.0 undecidable manual PN 234 1.5318 -0.23 1.6
--.BNI.Z. 1993-07-25T18:48:13.58 10.0 undecidable manual PN 306 1.3653 0.77 0.9
--.FRF.Z. 1993-07-25T18:48:13.70 10.0 undecidable manual PN 239 1.332 1.45 0.1
--.DOI.Z. 1993-07-25T18:48:13.50 10.0 undecidable manual SG 290 0.7437 -0.55 0.6
--.SBF.Z. 1993-07-25T18:48:11.29 10.0 undecidable manual SG 236 0.6882 -0.64 0.5
--.RRL.Z. 1993-07-25T18:48:11.16 10.0 undecidable manual PN 303 1.2321 0.22 1.8
--.STV.Z. 1993-07-25T18:48:09.60 10.0 undecidable manual SG 271 0.6438 -1.05 0.2
--.RSP.Z. 1993-07-25T18:48:09.54 10.0 undecidable manual PN 322 1.1433 -0.15 2
--.ENR.Z. 1993-07-25T18:48:09.60 10.0 undecidable manual SG 268 0.5772 1.02 0.2
--.BHB.Z. 1993-07-25T18:48:05.94 10.0 undecidable manual PG 310 0.9102 0.02 2.3
--.PZZ.Z. 1993-07-25T18:48:04.52 10.0 undecidable manual PG 288 0.8436 -0.29 2
--.IMI.Z. 1993-07-25T18:48:02.40 10.0 undecidable manual SG 216 0.3996 -0.67 0.5
--.SBF.Z. 1993-07-25T18:48:02.40 10.0 undecidable manual PG 236 0.6882 0.62 1.4
--.DOI.Z. 1993-07-25T18:48:02.91 10.0 undecidable manual PG 290 0.7437 -0.09 2.2
--.STV.Z. 1993-07-25T18:48:01.10 10.0 undecidable manual PG 271 0.6438 0.05 2.3
--.PCP.Z. 1993-07-25T18:48:00.80 10.0 undecidable manual SG 36 0.3663 -0.97 0.3
--.ENR.Z. 1993-07-25T18:47:59.88 10.0 undecidable manual PG 268 0.5772 0.03 2.3
--.ROB.Z. 1993-07-25T18:47:57.50 10.0 undecidable manual SG 283 0.2553 -0.89 0.3
--.CKI.Z. 1993-07-25T18:47:56.20 10.0 undecidable manual SG 9 0.1776 0.58 0.6
--.IMI.Z. 1993-07-25T18:47:56.20 10.0 undecidable manual PG 216 0.3996 -0.46 1.7
--.PCP.Z. 1993-07-25T18:47:55.62 10.0 undecidable manual PG 36 0.3663 -0.3 2
--.ROB.Z. 1993-07-25T18:47:54.00 10.0 undecidable manual PG 283 0.2553 0.04 2.3
--.CKI.Z. 1993-07-25T18:47:52.50 10.0 undecidable manual PG 9 0.1776 0.13 2.2
--.FIN.Z. 1993-07-25T18:47:51.30 10.0 undecidable manual SG 210 0.0333 -0.38 0.8
--.FIN.Z. 1993-07-25T18:47:50.22 10.0 undecidable manual PG 210 0.0333 0.13 2.2
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