Earthquake with magnitude of Md 2.3 on date 04-08-1991 and time 07:38:30 (Italy) in region 5 km SE Troina (EN)

A magnitude Md 2.3 earthquake occured in region: 5 km SE Troina (EN), on

  • 04-08-1991 05:38:30 (UTC)
  • 04-08-1991 07:38:30 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 37.7550, 14.6410 at 17 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
Troina EN 5 9373 9373
Gagliano Castelferrato EN 10 3593 12966
Regalbuto EN 11 7277 20243
San Teodoro ME 12 1403 21646
CesarĂ² ME 12 2439 24085
Cerami EN 13 2006 26091
Agira EN 15 8345 34436
Centuripe EN 17 5470 39906
Bronte CT 17 19172 59078
Capizzi ME 18 3176 62254
Maniace CT 19 3765 66019
Adrano CT 20 36122 102141

Municipalities with at least 50000 inhabitants

An earthquake occurred to
48 Km NW of Catania (314555 inhabitants)
49 Km W of Acireale (52622 inhabitants)
59 Km NE of Caltanissetta (63360 inhabitants)
84 Km NE of Gela (75827 inhabitants)
90 Km N of Vittoria (63339 inhabitants)
93 Km N of Ragusa (73313 inhabitants)
94 Km SW of Messina (238439 inhabitants)
96 Km NW of Siracusa (122291 inhabitants)
96 Km W of Reggio di Calabria (183035 inhabitants)
100 Km N of Modica (54633 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 2.4
1991-08-04
05:38:30
37.755 14.641 17 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 146829
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-08-04 05:38:30 ± 0.318
Latitude 37.7550 ± 0.0356
Longitude 14.6410 ± 0.0449
Depth (km) 17 ± 8 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 146829

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) 5589.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 129
Number of associated phases, regardless of their use for origin computation 12
Number of defining phases 12
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) 0.00478
Epicentral distance of station farthest from the epicenter (degree) 0.01684
Number of stations at which the event was observed 7
Number of stations from which data was used for origin computation 7
Magnitudes information

Md:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 4
Type of magnitude Md
Reference to an origin 146829
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:17:02

ML:2.4

Field Value
Value 2.4
Uncertainty
Num. used stations 2
Type of magnitude ML
Reference to an origin 146829
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
--.MO9.Z. 1991-08-04T05:39:01.50 10.0 undecidable manual SN 72 0.8658 1.23 0.1
--.CZI.Z. 1991-08-04T05:39:00.32 10.0 undecidable manual PN 37 1.8648 -1.17 0.2
--.PZI.Z. 1991-08-04T05:38:57.13 10.0 undecidable manual SG 160 0.7326 0.85 0.4
--.AU9.Z. 1991-08-04T05:38:54.65 10.0 undecidable manual SG 136 0.6771 0.28 0.7
--.MEU.Z. 1991-08-04T05:38:53.48 10.0 undecidable manual SG 166 0.6549 -0.28 0.6
--.SOI.Z. 1991-08-04T05:38:52.11 10.0 undecidable manual PN 73 1.1544 0.4 1.3
--.GIB.Z. 1991-08-04T05:38:49.24 10.0 undecidable manual SG 295 0.5328 -0.61 0.5
--.MO9.Z. 1991-08-04T05:38:47.50 10.0 undecidable manual PN 72 0.8658 -0.19 1.9
--.PZI.Z. 1991-08-04T05:38:45.18 10.0 undecidable manual PG 160 0.7326 -0.21 1.8
--.AU9.Z. 1991-08-04T05:38:44.16 10.0 undecidable manual PG 136 0.6771 -0.13 1.9
--.MEU.Z. 1991-08-04T05:38:43.85 10.0 undecidable manual PG 166 0.6549 -0.08 1.9
--.GIB.Z. 1991-08-04T05:38:42.54 10.0 undecidable manual PG 295 0.5328 0.87 0.8
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