Earthquake with magnitude of Md 2.0 on date 23-07-1991 and time 22:23:32 (Italy) in region 4 km NE Posta (RI)

A magnitude Md 2.0 earthquake occured in region: 4 km NE Posta (RI), on

  • 23-07-1991 20:23:32 (UTC)
  • 23-07-1991 22:23:32 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 42.5550, 13.1220 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 5 617 1311
Cittareale RI 8 482 1793
Montereale AQ 11 2581 4374
Micigliano RI 13 127 4501
Leonessa RI 13 2435 6936
Cagnano Amiterno AQ 14 1369 8305
Capitignano AQ 15 665 8970
Antrodoco RI 16 2588 11558
Amatrice RI 16 2657 14215
Borgo Velino RI 17 972 15187
Barete AQ 17 737 15924
Monteleone di Spoleto PG 18 599 16523
Accumoli RI 19 667 17190
Castel Sant'Angelo RI 19 1308 18498
Pizzoli AQ 19 4326 22824

Municipalities with at least 50000 inhabitants

An earthquake occurred to
32 Km NW of L'Aquila (69753 inhabitants)
39 Km E of Terni (111501 inhabitants)
49 Km W of Teramo (54892 inhabitants)
56 Km SE of Foligno (57155 inhabitants)
70 Km NE of Guidonia Montecelio (88673 inhabitants)
71 Km NE of Tivoli (56533 inhabitants)
84 Km W of Montesilvano (53738 inhabitants)
85 Km E of Viterbo (67173 inhabitants)
86 Km SE of Perugia (166134 inhabitants)
89 Km W of Chieti (51815 inhabitants)
90 Km W of Pescara (121014 inhabitants)
90 Km NE 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 2.0 1991-07-23
20:23:32
42.555 13.122 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 146119
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-07-23 20:23:32 ± 0.224
Latitude 42.5550 ± 0.0133
Longitude 13.1220 ± 0.0205
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 146119

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) 2236.7
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 126
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) 0.5
Epicentral distance of station closest to the epicenter (degree) 0.00259
Epicentral distance of station farthest from the epicenter (degree) 0.00356
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:2.0

Field Value
Value 2.0
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 146119
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:16:24
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.RMF.Z. 1991-07-23T20:23:47.83 10.0 undecidable manual SG 9 0.3996 0.07 0.8
--.ALP.Z. 1991-07-23T20:23:46.80 10.0 undecidable manual SG 55 0.3996 -0.73 0.3
--.MNS.Z. 1991-07-23T20:23:45.50 10.0 undecidable manual SG 242 0.3552 -1.08 0.1
--.AQU.Z. 1991-07-23T20:23:43.50 10.0 undecidable manual SG 134 0.2886 -0.53 0.6
--.MNS.Z. 1991-07-23T20:23:41.00 10.0 undecidable manual PG 242 0.3552 0.21 2.1
--.RMF.Z. 1991-07-23T20:23:41.92 10.0 undecidable manual PG 9 0.3996 0.45 1.5
--.AQU.Z. 1991-07-23T20:23:40.00 10.0 undecidable manual PG 134 0.2886 0.68 1
--.ALP.Z. 1991-07-23T20:23:40.90 10.0 undecidable manual PG 55 0.3996 -0.44 1.5
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