Earthquake with magnitude of Md 2.2 on date 18-09-1987 and time 12:09:28 (Italy) in region 5 km SW Norcia (PG)

A magnitude Md 2.2 earthquake occured in region: 5 km SW Norcia (PG), on

  • 18-09-1987 10:09:28 (UTC)
  • 18-09-1987 12:09:28 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.7640, 13.0450 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
Norcia PG 5 4957 4957
Cascia PG 6 3217 8174
Poggiodomo PG 11 117 8291
Cerreto di Spoleto PG 12 1075 9366
Preci PG 13 724 10090
Monteleone di Spoleto PG 15 599 10689
Vallo di Nera PG 15 364 11053
Sellano PG 17 1079 12132
Castelsantangelo sul Nera MC 17 281 12413
Sant'Anatolia di Narco PG 17 564 12977
Scheggino PG 18 461 13438
Accumoli RI 18 667 14105
Cittareale RI 19 482 14587
Visso MC 19 1107 15694

Municipalities with at least 50000 inhabitants

An earthquake occurred to
35 Km SE of Foligno (57155 inhabitants)
40 Km NE of Terni (111501 inhabitants)
54 Km NW of L'Aquila (69753 inhabitants)
55 Km W of Teramo (54892 inhabitants)
66 Km SE of Perugia (166134 inhabitants)
86 Km E of Viterbo (67173 inhabitants)
89 Km NE of Guidonia Montecelio (88673 inhabitants)
91 Km N of Tivoli (56533 inhabitants)
95 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
Bulletin
Rev1000
Md 2.2 1987-09-18
10:09:28
42.764 13.045 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 55639
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-09-18 10:09:28 ± 0.144
Latitude 42.7640 ± 0.0080
Longitude 13.0450 ± 0.0128
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 55639

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) 1375.5
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 128
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) 0.00340
Epicentral distance of station farthest from the epicenter (degree) 0.00664
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:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 1
Type of magnitude Md
Reference to an origin 55639
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:53:30
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.ARV.Z. 1987-09-18T10:09:54.50 10.0 undecidable manual SG 354 0.7326 -0.06 0.5
--.CM8.Z. 1987-09-18T10:09:45.60 10.0 undecidable manual SG 9 0.4329 0.18 0.9
--.MNS.Z. 1987-09-18T10:09:45.00 10.0 undecidable manual SG 215 0.4551 -0.77 0.1
--.ASS.Z. 1987-09-18T10:09:44.00 10.0 undecidable manual SG 316 0.4107 -0.17 0.6
--.ALP.Z. 1987-09-18T10:09:43.45 10.0 undecidable manual SG 87 0.3774 0.28 0.8
--.ARV.Z. 1987-09-18T10:09:43.00 10.0 undecidable manual PG 354 0.7326 -0.74 0.3
--.MNS.Z. 1987-09-18T10:09:38.80 10.0 positive manual PG 215 0.4551 0.14 3.2
--.CM8.Z. 1987-09-18T10:09:38.60 10.0 undecidable manual PG 9 0.4329 -0.09 1.6
--.ASS.Z. 1987-09-18T10:09:38.50 10.0 undecidable manual PG 316 0.4107 0.76 0.3
--.ALP.Z. 1987-09-18T10:09:37.80 10.0 undecidable manual PG 87 0.3774 -0.09 1.6
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
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