Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of Md 2.2 on date 21-12-1989 and time 03:21:48 (UTC) in region 2 km E Velletri (RM)

A magnitude Md 2.2 earthquake occured in region: 2 km E Velletri (RM), on

  • 21-12-1989 03:21:48 (UTC)
  • 21-12-1989 04:21:48 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 41.6930, 12.8020 at 5 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.

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Municipalities within 20 km from the epicenter

Distances are determinated based on the geographic coordintes of the (Istat).
Municipality Region Dist Inh Cum Inh
Velletri RM 2 53303 53303
Lariano RM 5 13432 66735
Nemi RM 8 1943 68678
Lanuvio RM 8 13632 82310
Genzano di Roma RM 9 23970 106280
Rocca Massima LT 10 1136 107416
Artena RM 11 14276 121692
Cori LT 11 11065 132757
Rocca di Papa RM 11 17034 149791
Cisterna di Latina LT 11 36868 186659
Ariccia RM 11 19407 206066
Rocca Priora RM 12 11962 218028
Albano Laziale RM 13 41715 259743
Labico RM 13 6379 266122
Valmontone RM 14 15959 282081
Castel Gandolfo RM 14 8997 291078
Monte Compatri RM 14 11978 303056
San Cesareo RM 14 15153 318209
Marino RM 15 43026 361235
Grottaferrata RM 15 20327 381562
Monte Porzio Catone RM 15 8693 390255
Frascati RM 16 22087 412342
Colonna RM 16 4287 416629
Zagarolo RM 17 17843 434472
Aprilia LT 17 73446 507918
Colleferro RM 18 21595 529513
Cave RM 18 11287 540800
Palestrina RM 18 21672 562472
Segni RM 18 9159 571631
Norma LT 19 3946 575577
Castel San Pietro Romano RM 19 902 576479
Gallicano nel Lazio RM 20 6334 582813

Municipalities with at least 50000 inhabitants

An earthquake occurred to
2 Km E of Velletri (53303 inhabitants)
17 Km NE of Aprilia (73446 inhabitants)
25 Km E of Pomezia (62966 inhabitants)
26 Km NW of Latina (125985 inhabitants)
30 Km S of Tivoli (56533 inhabitants)
31 Km NE of Anzio (54211 inhabitants)
35 Km SE of Roma (2864731 inhabitants)
35 Km S of Guidonia Montecelio (88673 inhabitants)
48 Km E of Fiumicino (78395 inhabitants)
88 Km SW of L'Aquila (69753 inhabitants)
95 Km E of Civitavecchia (52991 inhabitants)
97 Km S of Terni (111501 inhabitants)
99 Km SE of Viterbo (67173 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 1989-12-21
03:21:48		 41.693 12.802 5 2013-07-15
08:41:04		 Bollettino Sismico Italiano INGV 106419
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1989-12-21 03:21:48 ± 0.367
Latitude 41.6930 ± 0.0189
Longitude 12.8020 ± 0.0139
Depth (km) 5 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 106419

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) 2392.5
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 227
Number of associated phases, regardless of their use for origin computation 10
Number of defining phases 10
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.5
Epicentral distance of station closest to the epicenter (degree) 0.00081
Epicentral distance of station farthest from the epicenter (degree) 0.00672
Number of stations at which the event was observed 5
Number of stations from which data was used for origin computation 5
Magnitude information

Md:2.2

Field Value
Value 2.2
Uncertainty
Num. used stations 4
Type of magnitude Md
Reference to an origin 106419
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 18:39:06
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
--.SDI.Z. 1989-12-21T03:22:16.50 10.0 undecidable manual SG 88 0.7437 0.12 0.6
--.MNS.Z. 1989-12-21T03:22:13.44 10.0 undecidable manual SG 352 0.6882 -0.71 0.2
--.MNS.Z. 1989-12-21T03:22:03.20 10.0 undecidable manual PG 352 0.6882 -0.46 1.3
--.SDI.Z. 1989-12-21T03:22:03.76 10.0 undecidable manual PG 88 0.7437 -0.74 0.8
--.CP9.Z. 1989-12-21T03:21:56.98 10.0 undecidable manual SG 33 0.1998 0.08 1
--.CP9.Z. 1989-12-21T03:21:54.33 10.0 undecidable manual PG 33 0.1998 0.82 0.8
--.RMP.Z. 1989-12-21T03:21:54.00 10.0 undecidable manual SG 327 0.1332 -0.54 0.6
--.RMP.Z. 1989-12-21T03:21:52.50 10.0 undecidable manual PG 327 0.1332 0.34 1.9
--.RDP.Z. 1989-12-21T03:21:52.48 10.0 undecidable manual SG 316 0.0888 -0.33 0.9
--.RDP.Z. 1989-12-21T03:21:51.45 10.0 undecidable manual PG 316 0.0888 0.3 1.9
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