Earthquake with magnitude of Md 2.2 on date 30-09-1987 and time 03:58:13 (UTC) in region 4 km NE Chiusdino (SI)

A magnitude Md 2.2 earthquake occured in region: 4 km NE Chiusdino (SI), on

  • 30-09-1987 03:58:13 (UTC)
  • 30-09-1987 04:58:13 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 43.177, 11.129 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
Chiusdino SI 4 1903 1903
Monticiano SI 6 1571 3474
Montieri GR 10 1204 4678
Radicondoli SI 12 914 5592
Sovicille SI 14 10116 15708
Castelnuovo di Val di Cecina PI 18 2231 17939
Roccastrada GR 19 9199 27138
Casole d'Elsa SI 20 3897 31035

Municipalities with at least 50000 inhabitants

An earthquake occurred to
23 Km SW of Siena (53903 inhabitants)
46 Km N of Grosseto (82087 inhabitants)
65 Km S of Scandicci (50609 inhabitants)
67 Km S of Firenze (382808 inhabitants)
69 Km W of Arezzo (99543 inhabitants)
78 Km SE of Livorno (159219 inhabitants)
78 Km S of Prato (191150 inhabitants)
84 Km SE of Pisa (89158 inhabitants)
86 Km S of Pistoia (90315 inhabitants)
90 Km SE of Lucca (89046 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
ML-VAX 2.5
1987-09-30
03:58:13
43.177 11.129 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 56249
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-09-30 03:58:13 ± 0.375
Latitude 43.1770 ± 0.0194
Longitude 11.1290 ± 0.0739
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 56249

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) 6369
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 201
Number of associated phases, regardless of their use for origin computation 5
Number of defining phases 5
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) 0.00623
Epicentral distance of station farthest from the epicenter (degree) 0.00866
Number of stations at which the event was observed 3
Number of stations from which data was used for origin computation 3
Magnitudes information

Md:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 56249
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:54:02

ML:2.5

Field Value
Value 2.5
Uncertainty
Num. used stations 1
Type of magnitude ML
Reference to an origin 56249
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2015-04-28 13:07:13
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.MAO.Z. 1987-09-30T03:58:39.78 10.0 undecidable manual SG 178 0.0068 -0.41 0.5
--.PII.Z. 1987-09-30T03:58:38.00 10.0 undecidable manual SG 320 0.0062 -0.24 0.6
--.BDI.Z. 1987-09-30T03:58:32.50 10.0 undecidable manual PG 336 0.0087 -0.38 1
--.MAO.Z. 1987-09-30T03:58:29.21 10.0 undecidable manual PG 178 0.0068 0.13 2
--.PII.Z. 1987-09-30T03:58:28.50 10.0 undecidable manual PG 320 0.0062 0.55 0.9
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