Earthquake with magnitude of Md 2.1 on date 22-07-1991 and time 23:18:26 (Italy) in region 3 km NE Cascia (PG)

A magnitude Md 2.1 earthquake occured in region: 3 km NE Cascia (PG), on

  • 22-07-1991 21:18:26 (UTC)
  • 22-07-1991 23:18:26 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.74, 13.04 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
Cascia PG 3 3217 3217
Norcia PG 7 4957 8174
Poggiodomo PG 9 117 8291
Monteleone di Spoleto PG 12 599 8890
Cerreto di Spoleto PG 14 1075 9965
Vallo di Nera PG 15 364 10329
Preci PG 16 724 11053
Cittareale RI 16 482 11535
Sant'Anatolia di Narco PG 17 564 12099
Accumoli RI 17 667 12766
Scheggino PG 18 461 13227
Sellano PG 19 1079 14306
Castelsantangelo sul Nera MC 20 281 14587

Municipalities with at least 50000 inhabitants

An earthquake occurred to
37 Km SE of Foligno (57155 inhabitants)
38 Km NE of Terni (111501 inhabitants)
52 Km NW of L'Aquila (69753 inhabitants)
55 Km W of Teramo (54892 inhabitants)
67 Km SE of Perugia (166134 inhabitants)
85 Km E of Viterbo (67173 inhabitants)
86 Km NE of Guidonia Montecelio (88673 inhabitants)
88 Km N of Tivoli (56533 inhabitants)
94 Km W of Montesilvano (53738 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 2.1 1991-07-22
21:18:26
42.74 13.05 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 145989
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-07-22 21:18:26 ± 0.224
Latitude 42.74 ± 0.01
Longitude 13.05 ± 0.03
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 145989

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) 2401
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 188
Number of associated phases, regardless of their use for origin computation 10
Number of defining phases 10
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.2
Epicentral distance of station closest to the epicenter (degree) 0.00219
Epicentral distance of station farthest from the epicenter (degree) 0.0068
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:2.1

Field Value
Value 2.1
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 145989
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:16:17
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.ARV.Z. 1991-07-22T21:18:52.84 10.0 undecidable manual SG 354 0.0068 0.28 0.4
--.CIO.Z. 1991-07-22T21:18:43.18 10.0 undecidable manual SG 9 0.0041 0.3 0.5
--.MNS.Z. 1991-07-22T21:18:42.00 10.0 undecidable manual SG 217 0.004 -0.28 0.5
--.ASS.Z. 1991-07-22T21:18:41.57 10.0 undecidable manual SG 318 0.0039 -0.38 0.4
--.ARV.Z. 1991-07-22T21:18:41.41 10.0 undecidable manual PG 354 0.0068 0.02 1.4
--.MNS.Z. 1991-07-22T21:18:35.50 10.0 undecidable manual PG 217 0.004 0.04 1.9
--.CIO.Z. 1991-07-22T21:18:35.80 10.0 undecidable manual PG 9 0.0041 0 1.9
--.ASS.Z. 1991-07-22T21:18:35.35 10.0 undecidable manual PG 318 0.0039 0.09 1.8
--.RMF.Z. 1991-07-22T21:18:34.78 10.0 undecidable manual SG 29 0.0022 -1.2 0
--.RMF.Z. 1991-07-22T21:18:32.18 10.0 undecidable manual PG 29 0.0022 0.37 1.1
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
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