Earthquake with magnitude of Md 3.1 on date 25-08-1985 and time 21:00:18 (UTC) in region 7 km S Alcamo (TP)

A magnitude Md 3.1 earthquake occured in region: 7 km S Alcamo (TP), on

  • 25-08-1985 21:00:18 (UTC)
  • 25-08-1985 23:00:18 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 37.92, 12.96 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
Alcamo TP 7 45307 45307
Calatafimi-Segesta TP 9 6712 52019
Camporeale PA 12 3373 55392
Castellammare del Golfo TP 14 15394 70786
Vita TP 14 2056 72842
Gibellina TP 15 4115 76957
Balestrate PA 15 6436 83393
Trappeto PA 18 3174 86567
Santa Ninfa TP 18 5043 91610
Salemi TP 18 10794 102404
Salaparuta TP 19 1696 104100
Poggioreale TP 19 1494 105594
Roccamena PA 19 1505 107099
Partinico PA 20 32079 139178
San Cipirello PA 20 5372 144550

Municipalities with at least 50000 inhabitants

An earthquake occurred to
41 Km E of Trapani (68759 inhabitants)
41 Km SW of Palermo (674435 inhabitants)
44 Km NE of Mazara del Vallo (51718 inhabitants)
48 Km E of Marsala (83194 inhabitants)
51 Km W of Bagheria (55387 inhabitants)
87 Km NW of Agrigento (59770 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
Rev 1000 Md 3.1 1985-08-25
21:00:18
37.92 12.96 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 12339
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1985-08-25 21:00:18 ± 0.23
Latitude 37.92 ± 0.03
Longitude 12.96 ± 0.02
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 12339

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) 4024.8
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 153
Number of associated phases, regardless of their use for origin computation 6
Number of defining phases 6
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) 0.00283
Epicentral distance of station farthest from the epicenter (degree) 0.01603
Number of stations at which the event was observed 4
Number of stations from which data was used for origin computation 4
Magnitude information

Md:3.1

Field Value
Value 3.1
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 12339
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:15:36
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.PA1.Z. 1985-08-25T21:00:49.00 10.0 undecidable manual PN? 119 0.016 0.23 0.5
--.GIB.Z. 1985-08-25T21:00:48.00 10.0 undecidable manual SG 84 0.0075 0.88 0.4
--.FA1.Z. 1985-08-25T21:00:35.20 10.0 undecidable manual PG 138 0.0077 0.02 2
--.GIB.Z. 1985-08-25T21:00:34.00 10.0 undecidable manual PG 84 0.0075 -0.89 0.6
--.ERC.Z. 1985-08-25T21:00:30.00 10.0 undecidable manual SG 291 0.0028 -0.29 0.7
--.ERC.Z. 1985-08-25T21:00:25.50 10.0 undecidable manual PG 291 0.0028 0.33 1.8
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
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