Earthquake with magnitude of Md 2.3 on date 06-09-1991 and time 14:51:49 (UTC) in region 3 km W Monterotondo Marittimo (GR)

A magnitude Md 2.3 earthquake occured in region: 3 km W Monterotondo Marittimo (GR), on

  • 06-09-1991 14:51:49 (UTC)
  • 06-09-1991 16:51:49 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 43.1570, 10.8290 at 11 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
Monterotondo Marittimo GR 3 1371 1371
Castelnuovo di Val di Cecina PI 9 2231 3602
Monteverdi Marittimo PI 9 758 4360
Massa Marittima GR 13 8375 12735
Suvereto LI 15 3072 15807
Sassetta LI 15 514 16321
Montieri GR 16 1204 17525
Pomarance PI 16 5897 23422
Castagneto Carducci LI 18 9010 32432

Municipalities with at least 50000 inhabitants

An earthquake occurred to
45 Km W of Siena (53903 inhabitants)
50 Km NW of Grosseto (82087 inhabitants)
61 Km SE of Livorno (159219 inhabitants)
71 Km SE of Pisa (89158 inhabitants)
73 Km SW of Scandicci (50609 inhabitants)
76 Km SW of Firenze (382808 inhabitants)
81 Km SE of Lucca (89046 inhabitants)
83 Km S of Prato (191150 inhabitants)
87 Km S of Pistoia (90315 inhabitants)
92 Km SE of Viareggio (62467 inhabitants)
92 Km W of Arezzo (99543 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
ML-VAX 2.2
1991-09-06
14:51:49
43.157 10.829 11 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 148839
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-09-06 14:51:49 ± 0.299
Latitude 43.1570 ± 0.0194
Longitude 10.8290 ± 0.0507
Depth (km) 11 ± 4 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 148839

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) 4647.5
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 176
Number of associated phases, regardless of their use for origin computation 11
Number of defining phases 11
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.4
Epicentral distance of station closest to the epicenter (degree) 0.00542
Epicentral distance of station farthest from the epicenter (degree) 0.00939
Number of stations at which the event was observed 6
Number of stations from which data was used for origin computation 6
Magnitudes information

Md:2.3

Field Value
Value 2.3
Uncertainty
Num. used stations 2
Type of magnitude Md
Reference to an origin 148839
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:18:55

ML:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 3
Type of magnitude ML
Reference to an origin 148839
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(km) Takeoff_angle Residual Weight
--.MME.Z. 1991-09-06T14:52:23.92 10.0 undecidable manual SN 354 1.0323 -0.14 0.6
--.BDI.Z. 1991-09-06T14:52:20.33 10.0 undecidable manual SG 349 0.9213 -0.24 0.6
--.CRE.Z. 1991-09-06T14:52:20.00 10.0 undecidable manual SG 59 0.9324 -1.13 0.1
--.MAO.Z. 1991-09-06T14:52:14.82 10.0 undecidable manual SG 161 0.777 -1.16 0.1
--.SFI.Z. 1991-09-06T14:52:09.96 10.0 undecidable manual PN 44 1.0434 0.52 1.1
--.PII.Z. 1991-09-06T14:52:09.24 10.0 undecidable manual SG 338 0.5994 -1.23 0.1
--.MME.Z. 1991-09-06T14:52:09.67 10.0 undecidable manual PN 354 1.0323 0.37 1.3
--.CRE.Z. 1991-09-06T14:52:08.50 10.0 undecidable manual PG 59 0.9324 0.89 0.6
--.BDI.Z. 1991-09-06T14:52:07.77 10.0 undecidable manual PG 349 0.9213 0.48 1.2
--.MAO.Z. 1991-09-06T14:52:04.73 10.0 undecidable manual PG 161 0.777 0.09 1.7
--.PII.Z. 1991-09-06T14:52:01.52 10.0 negative manual PG 338 0.5994 0.06 3.5
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
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Type Description Link
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