Earthquake with magnitude of Md 2.2 on date 01-02-1987 and time 23:31:23 (Italy) in region 3 km SW Todi (PG)

A magnitude Md 2.2 earthquake occured in region: 3 km SW Todi (PG), on

  • 01-02-1987 22:31:23 (UTC)
  • 01-02-1987 23:31:23 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.7690, 12.3830 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
Todi PG 3 16851 16851
Monte Castello di Vibio PG 8 1567 18418
Fratta Todina PG 10 1839 20257
Massa Martana PG 12 3770 24027
Avigliano Umbro TR 13 2558 26585
Montecchio TR 14 1676 28261
San Venanzo TR 15 2218 30479
Collazzone PG 15 3473 33952
Montecastrilli TR 16 5022 38974
Acquasparta TR 16 4778 43752
Marsciano PG 16 18902 62654
Baschi TR 17 2722 65376
Giano dell'Umbria PG 18 3846 69222
Guardea TR 18 1836 71058
Castiglione in Teverina VT 20 2329 73387

Municipalities with at least 50000 inhabitants

An earthquake occurred to
32 Km NW of Terni (111501 inhabitants)
34 Km SW of Foligno (57155 inhabitants)
38 Km S of Perugia (166134 inhabitants)
45 Km NE of Viterbo (67173 inhabitants)
88 Km SE of Arezzo (99543 inhabitants)
89 Km NE of Civitavecchia (52991 inhabitants)
90 Km NW of Guidonia Montecelio (88673 inhabitants)
95 Km W of L'Aquila (69753 inhabitants)
96 Km NW of Tivoli (56533 inhabitants)
98 Km N of Roma (2864731 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 1987-02-01
22:31:23
42.769 12.383 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 40179
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-02-01 22:31:23 ± 0.513
Latitude 42.7690 ± 0.0216
Longitude 12.3830 ± 0.0663
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 40179

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) 5918.2
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 173
Number of associated phases, regardless of their use for origin computation 7
Number of defining phases 7
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.8
Epicentral distance of station closest to the epicenter (degree) 0.00316
Epicentral distance of station farthest from the epicenter (degree) 0.00882
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 40179
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:40:10
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.RMP.Z. 1987-02-01T22:31:57.00 10.0 undecidable manual SG 166 0.9768 -0.11 0.7
--.ARV.Z. 1987-02-01T22:31:53.00 10.0 undecidable manual SG 29 0.8214 0.7 0.6
--.RMP.Z. 1987-02-01T22:31:43.50 10.0 undecidable manual PG 166 0.9768 0.58 1.5
--.ARV.Z. 1987-02-01T22:31:42.00 10.0 undecidable manual PG 29 0.8214 1.85 0.5
--.CRE.Z. 1987-02-01T22:31:41.00 10.0 undecidable manual PG 340 0.8991 -0.45 1.6
--.AQU.Z. 1987-02-01T22:31:40.00 10.0 undecidable manual PG 118 0.8547 -0.54 1.6
--.ASS.Z. 1987-02-01T22:31:29.50 10.0 undecidable manual PG 34 0.3552 -1.7 0.6
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