Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of Md 2.5 on date 23-02-1991 and time 12:52:57 (UTC) in region 3 km NW Denice (AL)

A magnitude Md 2.5 earthquake occured in region: 3 km NW Denice (AL), on

  • 23-02-1991 12:52:57 (UTC)
  • 23-02-1991 13:52:57 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 44.6220, 8.3180 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
Denice AL 3 176 176
Monastero Bormida AT 3 931 1107
Ponti AL 4 606 1713
Roccaverano AT 5 399 2112
Bubbio AT 5 893 3005
Sessame AT 6 271 3276
Montechiaro d'Acqui AL 6 560 3836
Mombaldone AT 6 209 4045
San Giorgio Scarampi AT 6 122 4167
Bistagno AL 6 1887 6054
Castelletto d'Erro AL 6 148 6202
Cessole AT 7 403 6605
Olmo Gentile AT 7 80 6685
Loazzolo AT 7 359 7044
Vesime AT 7 622 7666
Cassinasco AT 8 611 8277
Perletto CN 9 292 8569
Cartosio AL 9 747 9316
Serole AT 9 123 9439
Spigno Monferrato AL 9 1050 10489
Melazzo AL 9 1325 11814
Terzo AL 10 923 12737
Rocchetta Palafea AT 10 338 13075
Malvicino AL 10 85 13160
Montabone AT 10 333 13493
Castino CN 11 483 13976
Cossano Belbo CN 11 958 14934
Cavatore AL 11 291 15225
Cortemilia CN 11 2331 17556
Canelli AT 11 10485 28041
Rocchetta Belbo CN 11 167 28208
Merana AL 12 189 28397
Santo Stefano Belbo CN 12 3984 32381
Ponzone AL 12 1051 33432
Castel Boglione AT 12 609 34041
Camo CN 13 201 34242
Pareto AL 13 554 34796
Calamandrana AT 13 1761 36557
Bergolo CN 13 71 36628
Pezzolo Valle Uzzone CN 13 344 36972
Castel Rocchero AT 13 395 37367
Acqui Terme AL 14 19896 57263
Bosia CN 14 177 57440
Grognardo AL 14 259 57699
Torre Bormida CN 14 200 57899
Borgomale CN 15 381 58280
San Marzano Oliveto AT 15 1047 59327
Calosso AT 15 1279 60606
Mango CN 15 1308 61914
Piana Crixia SV 15 788 62702
Visone AL 15 1194 63896
Morbello AL 15 402 64298
Castiglione Tinella CN 15 895 65193
Levice CN 16 231 65424
Alice Bel Colle AL 16 766 66190
Cravanzana CN 16 411 66601
Moasca AT 16 494 67095
Mioglia SV 16 526 67621
Benevello CN 17 474 68095
Fontanile AT 17 567 68662
Arguello CN 17 199 68861
Castelletto Molina AT 17 180 69041
Ricaldone AL 17 684 69725
Nizza Monferrato AT 17 10429 80154
Lequio Berria CN 18 487 80641
Trezzo Tinella CN 18 331 80972
Castelletto Uzzone CN 18 331 81303
Quaranti AT 18 183 81486
Neviglie CN 18 382 81868
Coazzolo AT 18 302 82170
Cerretto Langhe CN 18 442 82612
Strevi AL 18 2019 84631
Gorzegno CN 19 304 84935
Castelnuovo Calcea AT 19 759 85694
Prasco AL 19 521 86215
Feisoglio CN 19 316 86531
Morsasco AL 19 679 87210
Dego SV 19 1985 89195
Cassinelle AL 19 914 90109
Agliano Terme AT 20 1642 91751
Vaglio Serra AT 20 275 92026
Mombaruzzo AT 20 1117 93143
Treiso CN 20 820 93963
Neive CN 20 3405 97368
Castagnole delle Lanze AT 20 3798 101166
Maranzana AT 20 277 101443
Giusvalla SV 20 441 101884

Municipalities with at least 50000 inhabitants

An earthquake occurred to
32 Km S of Asti (76202 inhabitants)
37 Km NW of Savona (61345 inhabitants)
40 Km SW of Alessandria (93943 inhabitants)
54 Km W of Genova (586655 inhabitants)
65 Km SE of Moncalieri (57294 inhabitants)
66 Km E of Cuneo (56081 inhabitants)
71 Km SE of Torino (890529 inhabitants)
88 Km SW of Vigevano (63310 inhabitants)
91 Km SW of Pavia (72576 inhabitants)
95 Km S of Novara (104380 inhabitants)
99 Km NE of Sanremo (54807 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 2.5
M 2.8 		1991-02-23
12:52:57		 44.622 8.318 10 2013-07-15
08:40:51		 Bollettino Sismico Italiano INGV 136489
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-02-23 12:52:57 ± 0.523
Latitude 44.6220 ± 0.0105
Longitude 8.3180 ± 0.0158
Depth (km) 10 ± 4 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 136489

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) 1711.4
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 49
Number of associated phases, regardless of their use for origin computation 58
Number of defining phases 58
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) 0.00162
Epicentral distance of station farthest from the epicenter (degree) 0.03659
Number of stations at which the event was observed 32
Number of stations from which data was used for origin computation 32
Magnitudes information

Md:2.5

Field Value
Value 2.5
Uncertainty
Num. used stations 7
Type of magnitude Md
Reference to an origin 136489
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:07:15

M:2.8

Field Value
Value 2.8
Uncertainty
Num. used stations
Type of magnitude M
Reference to an origin 136489
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
--.LOR.Z. 1991-02-23T12:54:48.00 10.0 undecidable manual SN! 312 4.0626 3.65 0
--.HAU.Z. 1991-02-23T12:54:36.00 10.0 undecidable manual SN 338 3.6408 1.84 0
--.BSF.Z. 1991-02-23T12:54:29.60 10.0 undecidable manual SN 342 3.3744 1.81 0.1
--.LOR.Z. 1991-02-23T12:54:02.00 10.0 undecidable manual PN! 312 4.0626 2.98 0
--.LBF.Z. 1991-02-23T12:53:57.80 10.0 undecidable manual PN! 309 3.8295 2.04 0
--.CDF.Z. 1991-02-23T12:53:57.60 10.0 undecidable manual PN 349 3.8406 1.58 0.2
--.PGF.Z. 1991-02-23T12:53:56.40 10.0 undecidable manual SN 166 2.1201 -1.76 0.1
--.LMR.Z. 1991-02-23T12:53:54.40 10.0 undecidable manual SN! 226 1.8204 3.38 0
--.HAU.Z. 1991-02-23T12:53:54.20 10.0 undecidable manual PN 338 3.6408 1.07 0.5
--.LRG.Z. 1991-02-23T12:53:54.00 10.0 undecidable manual SN! 231 1.8204 3.05 0
--.BSF.Z. 1991-02-23T12:53:50.80 10.0 undecidable manual PN 342 3.3744 1.34 0.3
--.FRF.Z. 1991-02-23T12:53:48.00 10.0 undecidable manual SN! 229 1.5984 2.42 0
--.VAI.Z. 1991-02-23T12:53:38.00 10.0 undecidable manual SN 14 1.2765 -0.03 0.8
--.BNI.Z. 1991-02-23T12:53:36.49 10.0 undecidable manual SN 291 1.2321 -0.46 0.7
--.LSD.Z. 1991-02-23T12:53:33.40 10.0 undecidable manual SN 316 1.1655 -1.94 0
--.CDR.Z. 1991-02-23T12:53:32.70 10.0 undecidable manual PN 243 2.0535 1.32 0.5
--.RRL.Z. 1991-02-23T12:53:32.78 10.0 undecidable manual SN 286 1.1211 -1.55 0.1
--.PGF.Z. 1991-02-23T12:53:31.80 10.0 undecidable manual PN 166 2.1201 -0.55 1.2
--.ORX.Z. 1991-02-23T12:53:30.32 10.0 undecidable manual SN 347 1.0323 -1.84 0.1
--.ORO.Z. 1991-02-23T12:53:30.18 10.0 undecidable manual SN 346 1.0212 -1.87 0.1
--.LMR.Z. 1991-02-23T12:53:30.40 10.0 undecidable manual PN! 226 1.8204 2.17 0
--.LRG.Z. 1991-02-23T12:53:30.60 10.0 undecidable manual PN! 231 1.8204 2.42 0
--.SBF.Z. 1991-02-23T12:53:30.64 10.0 undecidable manual SG 220 0.9768 -0.02 0.8
--.FRF.Z. 1991-02-23T12:53:26.40 10.0 undecidable manual PN 229 1.5984 1.31 0.5
--.BOB.Z. 1991-02-23T12:53:26.00 10.0 undecidable manual SG 79 0.8103 0.8 0.5
--.RSP.Z. 1991-02-23T12:53:25.36 10.0 undecidable manual SG! 305 0.9213 -3.13 0
--.PZZ.Z. 1991-02-23T12:53:25.87 10.0 undecidable manual SG 262 0.8769 -1.2 0.3
--.STV.Z. 1991-02-23T12:53:24.16 10.0 undecidable manual SG 242 0.7881 -0.41 0.7
--.MDI.Z. 1991-02-23T12:53:23.00 10.0 undecidable manual PN 40 1.5096 -0.9 1
--.DOI.Z. 1991-02-23T12:53:23.10 10.0 undecidable manual SG 261 0.7659 -0.81 0.5
--.IMI.Z. 1991-02-23T12:53:23.31 10.0 undecidable manual SG 203 0.7659 -0.53 0.7
--.LPL.Z. 1991-02-23T12:53:23.60 10.0 undecidable manual PN 309 1.4319 0.84 1.2
--.ENR.Z. 1991-02-23T12:53:22.32 10.0 undecidable manual SG 238 0.7437 -0.83 0.5
--.VAI.Z. 1991-02-23T12:53:21.26 10.0 negative manual PN 14 1.2765 0.54 3.3
--.BNI.Z. 1991-02-23T12:53:20.50 10.0 undecidable manual PN 291 1.2321 0.39 1.8
--.RRL.Z. 1991-02-23T12:53:18.80 10.0 undecidable manual PN 286 1.1211 -0.51 1.6
--.LSD.Z. 1991-02-23T12:53:18.28 10.0 undecidable manual PN 316 1.1655 -0.89 1.1
--.SBF.Z. 1991-02-23T12:53:16.68 10.0 undecidable manual PG 220 0.9768 0.21 1.9
--.ORX.Z. 1991-02-23T12:53:16.75 10.0 undecidable manual PN 347 1.0323 -0.59 1.5
--.ORO.Z. 1991-02-23T12:53:16.96 10.0 undecidable manual PN 346 1.0212 -0.31 1.8
--.PZZ.Z. 1991-02-23T12:53:14.18 10.0 undecidable manual PG 262 0.8769 -0.22 1.9
--.ROB.Z. 1991-02-23T12:53:13.77 10.0 undecidable manual SG 225 0.444 0.3 0.7
--.STV.Z. 1991-02-23T12:53:13.50 10.0 undecidable manual PG 242 0.7881 0.09 1.9
--.RSP.Z. 1991-02-23T12:53:13.88 10.0 undecidable manual PG 305 0.9213 -1.34 0.5
--.IMI.Z. 1991-02-23T12:53:12.85 10.0 undecidable manual PG 203 0.7659 0.32 1.8
--.FIN.Z. 1991-02-23T12:53:12.44 10.0 undecidable manual SG 190 0.4107 -0.07 0.8
--.BHB.Z. 1991-02-23T12:53:12.16 10.0 undecidable manual PG 286 0.777 -0.47 1.7
--.BOB.Z. 1991-02-23T12:53:12.96 10.0 undecidable manual PG 79 0.8103 -0.36 1.8
--.DOI.Z. 1991-02-23T12:53:12.32 10.0 undecidable manual PG 261 0.7659 -0.2 1.9
--.ENR.Z. 1991-02-23T12:53:12.10 10.0 undecidable manual PG 238 0.7437 -0.13 1.9
--.ROB.Z. 1991-02-23T12:53:06.39 10.0 undecidable manual PG 225 0.444 -0.16 1.9
--.CKI.Z. 1991-02-23T12:53:06.45 10.0 undecidable manual SG 188 0.1998 0.89 0.4
--.FIN.Z. 1991-02-23T12:53:05.77 10.0 undecidable manual PG 190 0.4107 -0.23 1.9
--.AB9.Z. 1991-02-23T12:53:05.78 10.0 undecidable manual SG 292 0.1887 0.49 0.7
--.PCP.Z. 1991-02-23T12:53:03.42 10.0 undecidable manual SG 116 0.1776 -1.39 0.2
--.CKI.Z. 1991-02-23T12:53:02.26 10.0 positive manual PG 188 0.1998 0.28 3.6
--.AB9.Z. 1991-02-23T12:53:02.15 10.0 negative manual PG 292 0.1887 0.32 3.6
--.PCP.Z. 1991-02-23T12:53:00.96 10.0 undecidable manual PG 116 0.1776 -0.59 1.5
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