Earthquake with magnitude of Md 2.2 on date 21-09-1987 and time 04:06:00 (Italy) in region 7 km W Montemonaco (AP)

A magnitude Md 2.2 earthquake occured in region: 7 km W Montemonaco (AP), on

  • 21-09-1987 02:06:00 (UTC)
  • 21-09-1987 04:06:00 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.9, 13.25 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
Montemonaco AP 7 604 604
Castelsantangelo sul Nera MC 8 281 885
Montefortino FM 9 1178 2063
Montegallo AP 9 523 2586
Ussita MC 10 444 3030
Bolognola MC 11 142 3172
Amandola FM 13 3629 6801
Visso MC 13 1107 7908
Arquata del Tronto AP 15 1178 9086
Comunanza AP 15 3166 12252
Acquacanina MC 16 121 12373
Sarnano MC 16 3264 15637
Fiastra MC 17 559 16196
Preci PG 17 724 16920
Palmiano AP 17 196 17116
Norcia PG 17 4957 22073
Roccafluvione AP 19 2010 24083
Acquasanta Terme AP 20 2916 26999
Montefalcone Appennino FM 20 424 27423
Fiordimonte MC 20 202 27625
Smerillo FM 20 365 27990

Municipalities with at least 50000 inhabitants

An earthquake occurred to
45 Km E of Foligno (57155 inhabitants)
46 Km NW of Teramo (54892 inhabitants)
62 Km NE of Terni (111501 inhabitants)
62 Km N of L'Aquila (69753 inhabitants)
74 Km E of Perugia (166134 inhabitants)
83 Km S of Ancona (100861 inhabitants)
85 Km NW of Montesilvano (53738 inhabitants)
93 Km NW of Pescara (121014 inhabitants)
97 Km NW of Chieti (51815 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 2.2 1987-09-21
02:06:00
42.9 13.25 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 55789
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-09-21 02:06:00 ± 0.166
Latitude 42.90 ± 0.02
Longitude 13.25 ± 0.02
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 55789

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) 2150.6
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 8
Number of defining phases 8
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.3
Epicentral distance of station closest to the epicenter (degree) 0.00235
Epicentral distance of station farthest from the epicenter (degree) 0.00575
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 1
Type of magnitude Md
Reference to an origin 55789
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:53:39
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.ARV.Z. 1987-09-21T02:06:24.00 10.0 undecidable manual SG 339 0.0057 0.88 0
--.ASS.Z. 1987-09-21T02:06:17.50 10.0 undecidable manual SG 290 0.0041 -0.05 0.7
--.ARV.Z. 1987-09-21T02:06:14.00 10.0 undecidable manual PG 339 0.0057 0.35 1
--.CM8.Z. 1987-09-21T02:06:12.00 10.0 undecidable manual SG 345 0.0027 -0.4 0.7
--.ALP.Z. 1987-09-21T02:06:11.14 10.0 undecidable manual SG 117 0.0023 0.11 1.2
--.ASS.Z. 1987-09-21T02:06:10.37 10.0 undecidable manual PG 290 0.0041 -0.06 1.9
--.CM8.Z. 1987-09-21T02:06:06.90 10.0 undecidable manual PG 345 0.0027 -0.56 0.7
--.ALP.Z. 1987-09-21T02:06:06.48 10.0 undecidable manual PG 117 0.0023 -0.19 1.8
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
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