Earthquake with magnitude of Md 2.6 on date 02-10-1987 and time 17:41:31 (Italy) in region 3 km SW Grondona (AL)

A magnitude Md 2.6 earthquake occured in region: 3 km SW Grondona (AL), on

  • 02-10-1987 16:41:31 (UTC)
  • 02-10-1987 17:41:31 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 44.68, 8.95 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
Grondona AL 3 510 510
Isola del Cantone GE 3 1540 2050
Arquata Scrivia AL 5 6409 8459
Roccaforte Ligure AL 6 136 8595
Vignole Borbera AL 6 2182 10777
Borghetto di Borbera AL 6 1966 12743
Ronco Scrivia GE 7 4417 17160
Rocchetta Ligure AL 9 200 17360
Cantalupo Ligure AL 9 527 17887
Serravalle Scrivia AL 9 6128 24015
Stazzano AL 9 2486 26501
Sardigliano AL 10 406 26907
Carrosio AL 10 510 27417
Mongiardino Ligure AL 10 165 27582
Albera Ligure AL 10 325 27907
Voltaggio AL 11 738 28645
Vobbia GE 11 409 29054
Fraconalto AL 11 336 29390
Cabella Ligure AL 11 528 29918
Crocefieschi GE 12 548 30466
Busalla GE 12 5563 36029
Gavi AL 12 4614 40643
Gavazzana AL 12 180 40823
Cassano Spinola AL 12 1731 42554
Garbagna AL 12 696 43250
Sant'Agata Fossili AL 13 425 43675
Savignone GE 13 3205 46880
Dernice AL 13 185 47065
Bosio AL 13 1227 48292
Castellania AL 14 90 48382
Avolasca AL 14 294 48676
Carezzano AL 15 431 49107
San Sebastiano Curone AL 15 583 49690
Parodi Ligure AL 15 715 50405
Tassarolo AL 16 672 51077
Montacuto AL 16 278 51355
Valbrevenna GE 16 798 52153
Costa Vescovato AL 16 335 52488
Casella GE 16 3144 55632
Mornese AL 16 737 56369
San Cristoforo AL 16 608 56977
Novi Ligure AL 16 28154 85131
Mignanego GE 17 3675 88806
Brignano-Frascata AL 17 456 89262
Paderna AL 17 220 89482
Villalvernia AL 18 955 90437
Montaldeo AL 18 265 90702
Casasco AL 18 129 90831
Casaleggio Boiro AL 18 372 91203
Montegioco AL 18 313 91516
Pasturana AL 18 1318 92834
Gremiasco AL 18 324 93158
Fabbrica Curone AL 18 656 93814
Cerreto Grue AL 19 323 94137
Serra Riccò GE 19 7885 102022
Francavilla Bisio AL 19 531 102553
Carrega Ligure AL 19 84 102637
Pozzolo Formigaro AL 19 4775 107412
Spineto Scrivia AL 19 337 107749
Montoggio GE 19 2067 109816
Campomorone GE 19 6996 116812
Momperone AL 19 223 117035
Lerma AL 20 869 117904
Ceranesi GE 20 3875 121779
Montemarzino AL 20 341 122120
Castelletto d'Orba AL 20 2047 124167

Municipalities with at least 50000 inhabitants

An earthquake occurred to
29 Km N of Genova (586655 inhabitants)
38 Km SE of Alessandria (93943 inhabitants)
55 Km NE of Savona (61345 inhabitants)
59 Km S of Pavia (72576 inhabitants)
64 Km E of Asti (76202 inhabitants)
72 Km S of Vigevano (63310 inhabitants)
72 Km SW of Piacenza (102191 inhabitants)
90 Km SE of Novara (104380 inhabitants)
90 Km S of Milano (1345851 inhabitants)
94 Km NW of La Spezia (93959 inhabitants)
95 Km S of Rho (50434 inhabitants)
98 Km S of Sesto San Giovanni (81608 inhabitants)
99 Km SW of Cremona (71901 inhabitants)
100 Km S of Cinisello Balsamo (75078 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 2.6
ML-VAX 2.0
1987-10-02
16:41:31
44.68 8.95 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 56369
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-10-02 16:41:31 ± 1.218
Latitude 44.68 ± 0.06
Longitude 8.95 ± 0.11
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 56369

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) 10976.7
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 268
Number of associated phases, regardless of their use for origin computation 8
Number of defining phases 8
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.7
Epicentral distance of station closest to the epicenter (degree) 0.01052
Epicentral distance of station farthest from the epicenter (degree) 0.01481
Number of stations at which the event was observed 4
Number of stations from which data was used for origin computation 4
Magnitudes information

Md:2.6

Field Value
Value 2.6
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 56369
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:54:09

ML:2

Field Value
Value 2
Uncertainty
Num. used stations 3
Type of magnitude ML
Reference to an origin 56369
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2015-04-28 13:07:13
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.BNI.Z. 1987-10-02T16:42:23.20 10.0 undecidable manual SN 283 0.0148 1.84 0.1
--.VAI.Z. 1987-10-02T16:42:10.80 10.0 undecidable manual SN 353 0.0108 0.32 0.8
--.DA9.Z. 1987-10-02T16:42:10.20 10.0 undecidable manual SN 261 0.011 -1.02 0.5
--.ORO.Z. 1987-10-02T16:42:09.00 10.0 undecidable manual SN 323 0.0105 -0.89 0.5
--.BNI.Z. 1987-10-02T16:42:00.98 10.0 undecidable manual PN 283 0.0148 0.67 1.4
--.DA9.Z. 1987-10-02T16:41:54.20 10.0 undecidable manual PN 261 0.011 -0.25 2.1
--.VAI.Z. 1987-10-02T16:41:54.68 10.0 undecidable manual PN 353 0.0108 0.65 1.7
--.ORO.Z. 1987-10-02T16:41:52.50 10.0 undecidable manual PN 323 0.0105 -1.18 0.9
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
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QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download