Earthquake with magnitude of Md 2.3 on date 25-02-1987 and time 03:48:54 (UTC) in region 1 km SE Riolo Terme (RA)

A magnitude Md 2.3 earthquake occured in region: 1 km SE Riolo Terme (RA), on

  • 25-02-1987 03:48:54 (UTC)
  • 25-02-1987 04:48:54 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 44.271, 11.738 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
Riolo Terme RA 1 5720 5720
Brisighella RA 6 7639 13359
Castel Bolognese RA 7 9554 22913
Imola BO 9 69797 92710
Casalfiumanese BO 10 3438 96148
Casola Valsenio RA 10 2617 98765
Faenza RA 12 58541 157306
Borgo Tossignano BO 12 3288 160594
Solarolo RA 13 4488 165082
Dozza BO 13 6652 171734
Modigliana FC 13 4560 176294
Fontanelice BO 14 1943 178237
Bagnara di Romagna RA 15 2429 180666
Mordano BO 15 4760 185426
Castel San Pietro Terme BO 19 20811 206237
Castel Guelfo di Bologna BO 19 4455 210692
Castel del Rio BO 20 1246 211938
Castrocaro Terme e Terra del Sole FC 20 6426 218364

Municipalities with at least 50000 inhabitants

An earthquake occurred to
9 Km S of Imola (69797 inhabitants)
12 Km W of Faenza (58541 inhabitants)
25 Km W of Forlì (117913 inhabitants)
40 Km SE of Bologna (386663 inhabitants)
40 Km W of Ravenna (159116 inhabitants)
43 Km W of Cesena (96758 inhabitants)
64 Km S of Ferrara (133155 inhabitants)
67 Km NE of Prato (191150 inhabitants)
68 Km NE of Firenze (382808 inhabitants)
70 Km W of Rimini (147750 inhabitants)
72 Km NE of Scandicci (50609 inhabitants)
75 Km E of Pistoia (90315 inhabitants)
77 Km SE of Modena (184973 inhabitants)
88 Km SE of Carpi (70699 inhabitants)
89 Km S of Rovigo (51867 inhabitants)
90 Km N of Arezzo (99543 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 1987-02-25
03:48:54
44.271 11.738 5 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 41959
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-02-25 03:48:54 ± 0.516
Latitude 44.2710 ± 0.0296
Longitude 11.7380 ± 0.0435
Depth (km) 5 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 41959

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) 4775.3
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 133
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) 0.00364
Epicentral distance of station farthest from the epicenter (degree) 0.01595
Number of stations at which the event was observed 5
Number of stations from which data was used for origin computation 5
Magnitude information

Md:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 41959
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:41:42
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.BDI.Z. 1987-02-25T03:49:25.50 10.0 undecidable manual SG 256 0.0075 1.03 0.4
--.CTI.Z. 1987-02-25T03:49:25.00 10.0 undecidable manual PN 358 0.0159 -0.72 1
--.ARV.Z. 1987-02-25T03:49:18.50 10.0 undecidable manual PN 131 0.0104 1.22 0.7
--.CRE.Z. 1987-02-25T03:49:18.50 10.0 undecidable manual SG 166 0.006 -0.34 0.8
--.BDI.Z. 1987-02-25T03:49:11.50 10.0 undecidable manual PG 256 0.0075 -0.3 2
--.CRE.Z. 1987-02-25T03:49:08.00 10.0 undecidable manual PG 166 0.006 -0.55 1.7
--.MF9.Z. 1987-02-25T03:49:08.50 10.0 undecidable manual SG 166 0.0036 -1.76 0.1
--.MF9.Z. 1987-02-25T03:49:04.50 10.0 undecidable manual PG 166 0.0036 0.91 1.3
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
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