Earthquake with magnitude of Md 2.3 on date 09-12-1985 and time 06:21:25 (Italy) in region 7 km W Arquata del Tronto (AP)

A magnitude Md 2.3 earthquake occured in region: 7 km W Arquata del Tronto (AP), on

  • 09-12-1985 05:21:25 (UTC)
  • 09-12-1985 06:21:25 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.78, 13.22 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 7 1178 1178
Accumoli RI 9 667 1845
Norcia PG 10 4957 6802
Montegallo AP 12 523 7325
Castelsantangelo sul Nera MC 14 281 7606
Acquasanta Terme AP 16 2916 10522
Montemonaco AP 17 604 11126
Amatrice RI 17 2657 13783
Cascia PG 18 3217 17000
Cittareale RI 18 482 17482
Preci PG 19 724 18206
Ussita MC 20 444 18650

Municipalities with at least 50000 inhabitants

An earthquake occurred to
42 Km W of Teramo (54892 inhabitants)
46 Km E of Foligno (57155 inhabitants)
49 Km NW of L'Aquila (69753 inhabitants)
52 Km E of Terni (111501 inhabitants)
77 Km E of Perugia (166134 inhabitants)
82 Km W of Montesilvano (53738 inhabitants)
89 Km W of Pescara (121014 inhabitants)
91 Km NW of Chieti (51815 inhabitants)
95 Km NE of Guidonia Montecelio (88673 inhabitants)
96 Km NE of Tivoli (56533 inhabitants)
97 Km S of Ancona (100861 inhabitants)
99 Km E of Viterbo (67173 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 2.3 1985-12-09
05:21:25
42.78 13.22 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 17719
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1985-12-09 05:21:25 ± 0.224
Latitude 42.78 ± 0.01
Longitude 13.22 ± 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 17719

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) 2771.5
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 169
Number of associated phases, regardless of their use for origin computation 9
Number of defining phases 9
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) 0.00372
Epicentral distance of station farthest from the epicenter (degree) 0.00672
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:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 4
Type of magnitude Md
Reference to an origin 17719
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:20:32
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.ARV.Z. 1985-12-09T05:21:52.30 10.0 undecidable manual SG 344 0.0067 0.52 0.4
--.ASS.Z. 1985-12-09T05:21:44.00 10.0 undecidable manual SG 304 0.0045 0.16 0.8
--.AQU.Z. 1985-12-09T05:21:43.00 10.0 undecidable manual SG 161 0.004 1.07 0.1
--.CM2.Z. 1985-12-09T05:21:41.27 10.0 undecidable manual SG 352 0.0037 0.07 1.2
--.ARV.Z. 1985-12-09T05:21:40.50 10.0 undecidable manual PG 344 0.0067 -0.29 1.5
--.ASS.Z. 1985-12-09T05:21:37.00 10.0 undecidable manual PG 304 0.0045 0.79 0.7
--.MNS.Z. 1985-12-09T05:21:36.50 10.0 undecidable manual PG 225 0.0049 -0.68 0.9
--.AQU.Z. 1985-12-09T05:21:35.00 10.0 undecidable manual PG 161 0.004 -0.11 2
--.CM2.Z. 1985-12-09T05:21:34.18 10.0 undecidable manual PG 352 0.0037 -0.51 1.3
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Download
Type Description Link
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