Earthquake with magnitude of Md 2.3 on date 16-01-1987 and time 19:46:22 (Italy) in region 7 km E Civitella in Val di Chiana (AR)

A magnitude Md 2.3 earthquake occured in region: 7 km E Civitella in Val di Chiana (AR), on

  • 16-01-1987 18:46:22 (UTC)
  • 16-01-1987 19:46:22 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 43.3970, 11.8520 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
Civitella in Val di Chiana AR 7 9121 9121
Arezzo AR 8 99543 108664
Castiglion Fiorentino AR 8 13244 121908
Marciano della Chiana AR 11 3466 125374
Monte San Savino AR 12 8743 134117
Pergine Valdarno AR 16 3162 137279
Lucignano AR 16 3581 140860
Foiano della Chiana AR 16 9516 150376
Castiglion Fibocchi AR 16 2167 152543
Laterina AR 17 3517 156060
Cortona AR 17 22450 178510
Capolona AR 19 5438 183948
Subbiano AR 20 6331 190279

Municipalities with at least 50000 inhabitants

An earthquake occurred to
8 Km SW of Arezzo (99543 inhabitants)
43 Km E of Siena (53903 inhabitants)
54 Km NW of Perugia (166134 inhabitants)
63 Km SE of Firenze (382808 inhabitants)
67 Km SE of Scandicci (50609 inhabitants)
81 Km SE of Prato (191150 inhabitants)
85 Km NW of Foligno (57155 inhabitants)
88 Km SW of Cesena (96758 inhabitants)
93 Km NE of Grosseto (82087 inhabitants)
93 Km S of Forlì (117913 inhabitants)
94 Km SW of Rimini (147750 inhabitants)
96 Km SE of Pistoia (90315 inhabitants)
99 Km S of Faenza (58541 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 2.3 1987-01-16
18:46:22
43.397 11.852 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 39379
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-01-16 18:46:22 ± 0.489
Latitude 43.3970 ± 0.0376
Longitude 11.8520 ± 0.0395
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 39379

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) 5256.2
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 191
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) 0.9
Epicentral distance of station closest to the epicenter (degree) 0.00429
Epicentral distance of station farthest from the epicenter (degree) 0.00712
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:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 39379
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:39:27
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.ARV.Z. 1987-01-16T18:46:50.50 10.0 undecidable manual SG 82 0.7881 0.64 0.7
--.ASS.Z. 1987-01-16T18:46:46.50 10.0 undecidable manual SG 119 0.666 0.71 0.7
--.FIR.N. 1987-01-16T18:46:42.00 10.0 undecidable manual SG 311 0.5661 -0.6 0.8
--.MF9.Z. 1987-01-16T18:46:41.00 10.0 undecidable manual SG 1 0.4773 1.45 0.3
--.ARV.Z. 1987-01-16T18:46:37.00 10.0 undecidable manual PG 82 0.7881 -1.21 1
--.FIR.Z. 1987-01-16T18:46:35.00 10.0 undecidable manual PG 311 0.5661 0.98 1.4
--.ASS.Z. 1987-01-16T18:46:35.50 10.0 undecidable manual PG 119 0.666 -0.36 2.1
--.MF9.Z. 1987-01-16T18:46:31.00 10.0 undecidable manual PG 1 0.4773 -1.26 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