Earthquake with magnitude of Md 2.0 on date 22-10-1987 and time 23:55:05 (UTC) in region 4 km N Tredozio (FC)

A magnitude Md 2.0 earthquake occured in region: 4 km N Tredozio (FC), on

  • 22-10-1987 23:55:05 (UTC)
  • 23-10-1987 00:55:05 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 44.12, 11.74 at 19 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
Tredozio FC 4 1212 1212
Modigliana FC 6 4560 5772
Rocca San Casciano FC 11 1910 7682
Portico e San Benedetto FC 11 756 8438
Marradi FI 11 3139 11577
Brisighella RA 12 7639 19216
Dovadola FC 12 1653 20869
Casola Valsenio RA 15 2617 23486
Palazzuolo sul Senio FI 15 1154 24640
Premilcuore FC 16 799 25439
Riolo Terme RA 18 5720 31159
Castrocaro Terme e Terra del Sole FC 18 6426 37585
Galeata FC 19 2516 40101
Predappio FC 20 6346 46447

Municipalities with at least 50000 inhabitants

An earthquake occurred to
22 Km SW of Faenza (58541 inhabitants)
26 Km S of Imola (69797 inhabitants)
27 Km W of Forlì (117913 inhabitants)
41 Km W of Cesena (96758 inhabitants)
50 Km SW of Ravenna (159116 inhabitants)
52 Km SE of Bologna (386663 inhabitants)
54 Km NE of Firenze (382808 inhabitants)
57 Km E of Prato (191150 inhabitants)
60 Km NE of Scandicci (50609 inhabitants)
67 Km W of Rimini (147750 inhabitants)
69 Km E of Pistoia (90315 inhabitants)
73 Km N of Arezzo (99543 inhabitants)
81 Km S of Ferrara (133155 inhabitants)
87 Km SE of Modena (184973 inhabitants)
94 Km NE of Siena (53903 inhabitants)
97 Km W of Pesaro (94582 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 2.0
ML-VAX 1.8
1987-10-22
23:55:05
44.12 11.74 19 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 57489
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-10-22 23:55:05 ± 0.608
Latitude 44.12 ± 0.04
Longitude 11.74 ± 0.06
Depth (km) 19 ± 3 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 57489

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) 6883.8
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 302
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) 0.3
Epicentral distance of station closest to the epicenter (degree) 0.00186
Epicentral distance of station farthest from the epicenter (degree) 0.00955
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

Field Value
Value 2
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 57489
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:55:07

ML:1.8

Field Value
Value 1.8
Uncertainty
Num. used stations 1
Type of magnitude ML
Reference to an origin 57489
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
--.ARV.Z. 1987-10-22T23:55:25.40 10.0 undecidable manual PN 124 0.0096 0.34 0.9
--.CRE.Z. 1987-10-22T23:55:23.80 10.0 undecidable manual SG 162 0.0046 -0.5 0.4
--.PGD.Z. 1987-10-22T23:55:16.60 10.0 undecidable manual SG 182 0.0021 0.73 0.2
--.CRE.Z. 1987-10-22T23:55:15.68 10.0 undecidable manual PG 162 0.0046 -0.63 0.7
--.SS9.Z. 1987-10-22T23:55:15.46 10.0 undecidable manual SG 156 0.0019 0.38 0.6
--.SS9.Z. 1987-10-22T23:55:11.10 10.0 undecidable manual PG 156 0.0019 0.02 2.2
--.PGD.Z. 1987-10-22T23:55:11.20 10.0 undecidable manual PG 182 0.0021 -0.24 1.9
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
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