Earthquake with magnitude of Md 2.2 on date 19-12-1987 and time 21:56:18 (Italy) in region 4 km W Monterotondo Marittimo (GR)

A magnitude Md 2.2 earthquake occured in region: 4 km W Monterotondo Marittimo (GR), on

  • 19-12-1987 20:56:18 (UTC)
  • 19-12-1987 21:56:18 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 43.1330, 10.8070 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
Monterotondo Marittimo GR 4 1371 1371
Monteverdi Marittimo PI 9 758 2129
Massa Marittima GR 11 8375 10504
Castelnuovo di Val di Cecina PI 12 2231 12735
Suvereto LI 12 3072 15807
Sassetta LI 13 514 16321
Castagneto Carducci LI 16 9010 25331
Montieri GR 17 1204 26535
Campiglia Marittima LI 17 13218 39753
Pomarance PI 20 5897 45650

Municipalities with at least 50000 inhabitants

An earthquake occurred to
47 Km W of Siena (53903 inhabitants)
48 Km NW of Grosseto (82087 inhabitants)
62 Km SE of Livorno (159219 inhabitants)
73 Km SE of Pisa (89158 inhabitants)
76 Km SW of Scandicci (50609 inhabitants)
80 Km SW of Firenze (382808 inhabitants)
83 Km SE of Lucca (89046 inhabitants)
87 Km S of Prato (191150 inhabitants)
90 Km S of Pistoia (90315 inhabitants)
93 Km SE of Viareggio (62467 inhabitants)
95 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 2.2
ML-VAX 1.5
1987-12-19
20:56:18
43.133 10.807 10 2013-07-15
08:41:04
Bollettino Sismico Italiano INGV 59809
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-12-19 20:56:18 ± 0.288
Latitude 43.1330 ± 0.0149
Longitude 10.8070 ± 0.0596
Depth (km) 10 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 59809

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) 5112.6
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 180
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) 0.3
Epicentral distance of station closest to the epicenter (degree) 0.00559
Epicentral distance of station farthest from the epicenter (degree) 0.00955
Number of stations at which the event was observed 5
Number of stations from which data was used for origin computation 5
Magnitudes information

Md:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 59809
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:57:08

ML:1.5

Field Value
Value 1.5
Uncertainty
Num. used stations 1
Type of magnitude ML
Reference to an origin 59809
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
--.BDI.Z. 1987-12-19T20:56:51.50 10.0 undecidable manual SG 350 0.9324 0.39 0.5
--.MAO.Z. 1987-12-19T20:56:45.12 10.0 undecidable manual SG 160 0.7548 -0.17 0.6
--.MME.Z. 1987-12-19T20:56:41.70 10.0 undecidable manual PN? 355 1.0656 1.44 0
--.PII.Z. 1987-12-19T20:56:40.00 10.0 undecidable manual SG 340 0.6216 -0.88 0.2
--.PGD.Z. 1987-12-19T20:56:38.25 10.0 undecidable manual PG 41 0.9879 -0.28 1.3
--.BDI.Z. 1987-12-19T20:56:38.00 10.0 undecidable manual PG 350 0.9324 0.47 1
--.MAO.Z. 1987-12-19T20:56:34.17 10.0 positive manual PG 160 0.7548 -0.01 3.3
--.PII.Z. 1987-12-19T20:56:31.12 10.0 undecidable manual PG 340 0.6216 -0.52 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