Earthquake with magnitude of Md 2.8 on date 20-08-1991 and time 11:08:35 (UTC) in region 3 km NW Sellano (PG)

A magnitude Md 2.8 earthquake occured in region: 3 km NW Sellano (PG), on

  • 20-08-1991 11:08:35 (UTC)
  • 20-08-1991 13:08:35 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.91, 12.89 at 8 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
Sellano PG 3 1079 1079
Cerreto di Spoleto PG 10 1075 2154
Trevi PG 12 8469 10623
Preci PG 12 724 11347
Monte Cavallo MC 13 145 11492
Campello sul Clitunno PG 13 2442 13934
Vallo di Nera PG 15 364 14298
Visso MC 16 1107 15405
Foligno PG 16 57155 72560
Serravalle di Chienti MC 19 1070 73630
Montefalco PG 20 5679 79309
Sant'Anatolia di Narco PG 20 564 79873

Municipalities with at least 50000 inhabitants

An earthquake occurred to
16 Km E of Foligno (57155 inhabitants)
43 Km NE of Terni (111501 inhabitants)
47 Km E of Perugia (166134 inhabitants)
72 Km W of Teramo (54892 inhabitants)
74 Km NW of L'Aquila (69753 inhabitants)
84 Km NE of Viterbo (67173 inhabitants)
94 Km SW of Ancona (100861 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 2.8
ML-VAX 1.7
1991-08-20
11:08:35
42.91 12.89 9 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 147709
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-08-20 11:08:35 ± 0.525
Latitude 42.91 ± 0.02
Longitude 12.89 ± 0.05
Depth (km) 9 ± 4 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 147709

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) 4070.3
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 142
Number of associated phases, regardless of their use for origin computation 15
Number of defining phases 15
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) 0.0021
Epicentral distance of station farthest from the epicenter (degree) 0.0123
Number of stations at which the event was observed 9
Number of stations from which data was used for origin computation 9
Magnitudes information

Md:2.8

Field Value
Value 2.8
Uncertainty
Num. used stations 5
Type of magnitude Md
Reference to an origin 147709
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:17:52

ML:1.7

Field Value
Value 1.7
Uncertainty
Num. used stations 3
Type of magnitude ML
Reference to an origin 147709
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
--.RDP.Z. 1991-08-20T11:09:14.50 10.0 undecidable manual SN 186 0.0104 0.41 0.6
--.CP9.Z. 1991-08-20T11:09:12.79 10.0 undecidable manual SN 177 0.0094 1.3 0.3
--.AZI.Z. 1991-08-20T11:09:10.79 10.0 undecidable manual SG 156 0.009 0.65 0.5
--.SDI.Z. 1991-08-20T11:09:01.56 10.0 undecidable manual PN 149 0.0123 0.64 1.1
--.ARV.Z. 1991-08-20T11:08:57.90 10.0 undecidable manual SG 3 0.0053 0.11 0.8
--.AZI.Z. 1991-08-20T11:08:57.41 10.0 undecidable manual PG 156 0.009 1.81 0.3
--.RDP.Z. 1991-08-20T11:08:57.90 10.0 undecidable manual PN 186 0.0104 0.01 1.6
--.CP9.Z. 1991-08-20T11:08:56.66 10.0 undecidable manual PN 177 0.0094 0.28 1.6
--.MNS.Z. 1991-08-20T11:08:55.26 10.0 undecidable manual SG 196 0.0049 -0.16 0.8
--.CRE.Z. 1991-08-20T11:08:55.50 10.0 undecidable manual PG 316 0.0088 0.16 1.7
--.AQU.Z. 1991-08-20T11:08:48.51 10.0 undecidable manual PG 145 0.006 -0.88 1.3
--.ARV.Z. 1991-08-20T11:08:46.87 10.0 undecidable manual PG 3 0.0053 -1.14 1
--.ASS.Z. 1991-08-20T11:08:46.66 10.0 undecidable manual SG 311 0.0021 1.4 0.3
--.MNS.Z. 1991-08-20T11:08:45.71 10.0 positive manual PG 196 0.0049 -1.39 1.4
--.ASS.Z. 1991-08-20T11:08:41.48 10.0 undecidable manual PG 311 0.0021 0.24 1.9
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
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