Earthquake with magnitude of Md 2.2 on date 20-10-1987 and time 23:12:45 (UTC) in region 4 km NW Posta (RI)

A magnitude Md 2.2 earthquake occured in region: 4 km NW Posta (RI), on

  • 20-10-1987 23:12:45 (UTC)
  • 21-10-1987 00:12:45 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 42.5590, 13.0700 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
Posta RI 4 694 694
Borbona RI 7 617 1311
Leonessa RI 9 2435 3746
Cittareale RI 10 482 4228
Micigliano RI 12 127 4355
Monteleone di Spoleto PG 14 599 4954
Montereale AQ 15 2581 7535
Antrodoco RI 16 2588 10123
Poggio Bustone RI 16 2055 12178
Cantalice RI 17 2755 14933
Cagnano Amiterno AQ 17 1369 16302
Borgo Velino RI 17 972 17274
Rivodutri RI 18 1253 18527
Castel Sant'Angelo RI 18 1308 19835
Cascia PG 18 3217 23052
Polino TR 19 233 23285
Capitignano AQ 19 665 23950
Amatrice RI 20 2657 26607
Morro Reatino RI 20 373 26980

Municipalities with at least 50000 inhabitants

An earthquake occurred to
35 Km E of Terni (111501 inhabitants)
36 Km NW of L'Aquila (69753 inhabitants)
53 Km W of Teramo (54892 inhabitants)
53 Km SE of Foligno (57155 inhabitants)
68 Km NE of Guidonia Montecelio (88673 inhabitants)
70 Km NE of Tivoli (56533 inhabitants)
81 Km E of Viterbo (67173 inhabitants)
83 Km SE of Perugia (166134 inhabitants)
88 Km NE of Roma (2864731 inhabitants)
89 Km W of Montesilvano (53738 inhabitants)
93 Km W of Chieti (51815 inhabitants)
94 Km W of Pescara (121014 inhabitants)
100 Km N of Velletri (53303 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 1987-10-20
23:12:45
42.559 13.07 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 57349
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-10-20 23:12:45 ± 0.138
Latitude 42.5590 ± 0.0085
Longitude 13.0700 ± 0.0133
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 57349

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) 1440.9
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 92
Number of associated phases, regardless of their use for origin computation 14
Number of defining phases 14
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) 0.00283
Epicentral distance of station farthest from the epicenter (degree) 0.00907
Number of stations at which the event was observed 7
Number of stations from which data was used for origin computation 7
Magnitude information

Md:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 4
Type of magnitude Md
Reference to an origin 57349
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:55:00
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.SDI.Z. 1987-10-20T23:13:21.60 10.0 undecidable manual SG! 147 1.0101 1.59 0
--.ARV.Z. 1987-10-20T23:13:17.10 10.0 undecidable manual SG 354 0.9324 -0.31 0.3
--.CM8.Z. 1987-10-20T23:13:07.65 10.0 undecidable manual SG 5 0.6327 0.15 0.8
--.ASS.Z. 1987-10-20T23:13:06.50 10.0 undecidable manual SG 329 0.5883 0.57 0.2
--.SDI.Z. 1987-10-20T23:13:05.34 10.0 undecidable manual PG 147 1.0101 0.4 0.7
--.ARV.Z. 1987-10-20T23:13:03.39 10.0 undecidable manual PG 354 0.9324 -0.31 0.8
--.ALP.Z. 1987-10-20T23:13:01.32 10.0 undecidable manual SG 58 0.4218 0.58 0.3
--.ASS.Z. 1987-10-20T23:12:57.00 10.0 undecidable manual PG 329 0.5883 -0.13 1.4
--.MNS.Z. 1987-10-20T23:12:57.90 10.0 undecidable manual SG 239 0.333 0.13 0.6
--.CM8.Z. 1987-10-20T23:12:57.64 10.0 undecidable manual PG 5 0.6327 -0.39 0.9
--.AQU.Z. 1987-10-20T23:12:55.92 10.0 undecidable manual SG 129 0.3108 -1.34 0
--.ALP.Z. 1987-10-20T23:12:54.48 10.0 undecidable manual PG 58 0.4218 0.34 1
--.MNS.Z. 1987-10-20T23:12:52.50 10.0 negative manual PG 239 0.333 0.08 3
--.AQU.Z. 1987-10-20T23:12:52.20 10.0 negative manual PG 129 0.3108 0.08 3
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
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