Earthquake with magnitude of Md 2.3 on date 19-10-1987 and time 11:22:30 (Italy) in region Costa Toscana settentrionale (Massa Carrara, Lucca, Pisa)

A magnitude Md 2.3 earthquake occured in region: Costa Toscana settentrionale (Massa Carrara, Lucca, Pisa), on

  • 19-10-1987 10:22:30 (UTC)
  • 19-10-1987 11:22:30 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 43.9630, 9.8330 at 5 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
Portovenere SP 10 3630 3630
Lerici SP 14 10228 13858
Ameglia SP 15 4365 18223
La Spezia SP 16 93959 112182
Riomaggiore SP 17 1576 113758
Arcola SP 18 10607 124365
Sarzana SP 20 21976 146341

Municipalities with at least 50000 inhabitants

An earthquake occurred to
16 Km S of La Spezia (93959 inhabitants)
25 Km SW of Carrara (63133 inhabitants)
26 Km W of Massa (69479 inhabitants)
35 Km W of Viareggio (62467 inhabitants)
53 Km NW of Pisa (89158 inhabitants)
55 Km W of Lucca (89046 inhabitants)
60 Km NW of Livorno (159219 inhabitants)
87 Km W of Pistoia (90315 inhabitants)
87 Km SE of Genova (586655 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 2.3
ML-VAX 1.8
1987-10-19
10:22:30
43.963 9.833 5 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 57199
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-10-19 10:22:30 ± 0.245
Latitude 43.9630 ± 0.0214
Longitude 9.8330 ± 0.0228
Depth (km) 5 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 57199

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) 2993.6
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 171
Number of associated phases, regardless of their use for origin computation 7
Number of defining phases 7
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.5
Epicentral distance of station closest to the epicenter (degree) 0.00494
Epicentral distance of station farthest from the epicenter (degree) 0.01732
Number of stations at which the event was observed 6
Number of stations from which data was used for origin computation 6
Magnitudes information

Md:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 57199
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:54:52

ML:1.8

Field Value
Value 1.8
Uncertainty
Num. used stations 3
Type of magnitude ML
Reference to an origin 57199
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(km) Takeoff_angle Residual Weight
--.DOI.Z. 1987-10-19T10:23:04.11 10.0 undecidable manual PN 287 1.9203 0.34 1.1
--.BOB.Z. 1987-10-19T10:23:00.67 10.0 undecidable manual SG 341 0.8436 0.11 0.7
--.CRE.Z. 1987-10-19T10:22:59.28 10.0 undecidable manual PN 102 1.5651 0.52 0.9
--.CKI.Z. 1987-10-19T10:22:53.89 10.0 undecidable manual PN 293 1.1988 0.1 1.7
--.BOB.Z. 1987-10-19T10:22:47.15 10.0 undecidable manual PG 341 0.8436 -0.68 0.8
--.MME.Z. 1987-10-19T10:22:44.90 10.0 undecidable manual PG 69 0.6549 0.51 1.2
--.PII.Z. 1987-10-19T10:22:41.50 10.0 undecidable manual PG 116 0.5439 -0.84 0.5
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