Earthquake with magnitude of Md 2.2 on date 21-03-1993 and time 00:20:40 (UTC) in region 8 km E Volterra (PI)

A magnitude Md 2.2 earthquake occured in region: 8 km E Volterra (PI), on

  • 21-03-1993 00:20:40 (UTC)
  • 21-03-1993 01:20:40 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 43.4290, 10.9510 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
Volterra PI 8 10519 10519
San Gimignano SI 9 7820 18339
Casole d'Elsa SI 12 3897 22236
Gambassi Terme FI 12 4870 27106
Colle di Val d'Elsa SI 14 21620 48726
Montaione FI 14 3700 52426
Certaldo FI 15 16121 68547
Pomarance PI 16 5897 74444
Poggibonsi SI 16 29196 103640
Montecatini Val di Cecina PI 17 1749 105389
Lajatico PI 19 1336 106725
Castelfiorentino FI 20 17504 124229
Radicondoli SI 20 914 125143

Municipalities with at least 50000 inhabitants

An earthquake occurred to
33 Km W of Siena (53903 inhabitants)
41 Km SW of Scandicci (50609 inhabitants)
45 Km SW of Firenze (382808 inhabitants)
52 Km S of Prato (191150 inhabitants)
54 Km E of Livorno (159219 inhabitants)
55 Km SE of Pisa (89158 inhabitants)
56 Km S of Pistoia (90315 inhabitants)
59 Km SE of Lucca (89046 inhabitants)
75 Km SE of Viareggio (62467 inhabitants)
75 Km N of Grosseto (82087 inhabitants)
75 Km W of Arezzo (99543 inhabitants)
94 Km SE of Massa (69479 inhabitants)
100 Km SE of Carrara (63133 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 1993-03-21
00:20:40
43.429 10.951 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 182019
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1993-03-21 00:20:40 ± 0.473
Latitude 43.4290 ± 0.0315
Longitude 10.9510 ± 0.0216
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 182019

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) 3909.1
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 238
Number of associated phases, regardless of their use for origin computation 7
Number of defining phases 7
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) 0.00380
Epicentral distance of station farthest from the epicenter (degree) 0.00672
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:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 182019
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:50:49
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.CRE.Z. 1993-03-21T00:21:06.00 10.0 undecidable manual SG 74 0.7437 -0.8 0
--.BDI.Z. 1993-03-21T00:21:04.73 10.0 undecidable manual SG 337 0.6771 0.08 0.6
--.PII.Z. 1993-03-21T00:20:56.45 10.0 undecidable manual SG 313 0.4218 0.07 0.6
--.CRE.Z. 1993-03-21T00:20:56.20 10.0 negative manual PG 74 0.7437 0.19 2.4
--.PGD.Z. 1993-03-21T00:20:55.20 10.0 undecidable manual PG 50 0.7104 0.03 1.5
--.BDI.Z. 1993-03-21T00:20:54.81 10.0 undecidable manual PG 337 0.6771 0.23 1.2
--.PII.Z. 1993-03-21T00:20:49.42 10.0 undecidable manual PG 313 0.4218 -0.39 0.7
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