Earthquake with magnitude of Md 2.2 on date 22-04-1987 and time 22:30:36 (Italy) in region 2 km S Arquata del Tronto (AP)

A magnitude Md 2.2 earthquake occured in region: 2 km S Arquata del Tronto (AP), on

  • 22-04-1987 20:30:36 (UTC)
  • 22-04-1987 22:30:36 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.7580, 13.2990 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
Arquata del Tronto AP 2 1178 1178
Accumoli RI 8 667 1845
Acquasanta Terme AP 9 2916 4761
Montegallo AP 10 523 5284
Amatrice RI 14 2657 7941
Montemonaco AP 16 604 8545
Valle Castellana TE 17 977 9522
Norcia PG 17 4957 14479
Roccafluvione AP 19 2010 16489
Cittareale RI 19 482 16971
Castelsantangelo sul Nera MC 19 281 17252

Municipalities with at least 50000 inhabitants

An earthquake occurred to
35 Km W of Teramo (54892 inhabitants)
46 Km N of L'Aquila (69753 inhabitants)
53 Km E of Foligno (57155 inhabitants)
58 Km E of Terni (111501 inhabitants)
75 Km W of Montesilvano (53738 inhabitants)
82 Km W of Pescara (121014 inhabitants)
84 Km E of Perugia (166134 inhabitants)
84 Km NW of Chieti (51815 inhabitants)
96 Km NE of Guidonia Montecelio (88673 inhabitants)
97 Km NE of Tivoli (56533 inhabitants)
97 Km S 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 2.2 1987-04-22
20:30:36
42.758 13.299 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 45419
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-04-22 20:30:36 ± 0.603
Latitude 42.7580 ± 0.0273
Longitude 13.2990 ± 0.0301
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 45419

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) 3902.1
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 287
Number of associated phases, regardless of their use for origin computation 8
Number of defining phases 8
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) 0.00405
Epicentral distance of station farthest from the epicenter (degree) 0.00737
Number of stations at which the event was observed 4
Number of stations from which data was used for origin computation 4
Magnitude information

Md:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 45419
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:44:44
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.AM8.Z. 1987-04-22T20:31:05.59 10.0 undecidable manual SG 15 0.8214 0.92 0.2
--.ARV.Z. 1987-04-22T20:31:03.40 10.0 undecidable manual SG 340 0.777 -0.11 0.8
--.ASS.Z. 1987-04-22T20:30:57.00 10.0 undecidable manual SG 302 0.555 0.62 0.4
--.AM8.Z. 1987-04-22T20:30:53.50 10.0 undecidable manual PG 15 0.8214 0.32 1.7
--.CM8.Z. 1987-04-22T20:30:52.52 10.0 undecidable manual SG 345 0.444 -0.28 0.8
--.ARV.Z. 1987-04-22T20:30:51.50 10.0 undecidable manual PG 340 0.777 -0.55 1.2
--.ASS.Z. 1987-04-22T20:30:48.30 10.0 undecidable manual PG 302 0.555 0.35 1.8
--.CM8.Z. 1987-04-22T20:30:45.26 10.0 undecidable manual PG 345 0.444 -0.62 1.1
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