Earthquake with magnitude of Md 2.1 on date 12-01-1991 and time 13:44:02 (Italy) in region 1 km NE Ariccia (RM)

A magnitude Md 2.1 earthquake occured in region: 1 km NE Ariccia (RM), on

  • 12-01-1991 12:44:02 (UTC)
  • 12-01-1991 13:44:02 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 41.7240, 12.6770 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
Ariccia RM 1 19407 19407
Albano Laziale RM 2 41715 61122
Genzano di Roma RM 2 23970 85092
Nemi RM 3 1943 87035
Castel Gandolfo RM 3 8997 96032
Rocca di Papa RM 5 17034 113066
Lanuvio RM 5 13632 126698
Marino RM 5 43026 169724
Grottaferrata RM 7 20327 190051
Frascati RM 9 22087 212138
Velletri RM 9 53303 265441
Monte Compatri RM 11 11978 277419
Rocca Priora RM 11 11962 289381
Ciampino RM 11 38412 327793
Monte Porzio Catone RM 11 8693 336486
Lariano RM 13 13432 349918
Colonna RM 14 4287 354205
Aprilia LT 15 73446 427651
San Cesareo RM 15 15153 442804
Pomezia RM 16 62966 505770
Ardea RM 17 49183 554953
Zagarolo RM 18 17843 572796
Labico RM 19 6379 579175
Cisterna di Latina LT 19 36868 616043

Municipalities with at least 50000 inhabitants

An earthquake occurred to
9 Km W of Velletri (53303 inhabitants)
15 Km N of Aprilia (73446 inhabitants)
16 Km E of Pomezia (62966 inhabitants)
25 Km SE of Roma (2864731 inhabitants)
29 Km SW of Tivoli (56533 inhabitants)
31 Km N of Anzio (54211 inhabitants)
31 Km S of Guidonia Montecelio (88673 inhabitants)
34 Km NW of Latina (125985 inhabitants)
37 Km E of Fiumicino (78395 inhabitants)
84 Km SE of Civitavecchia (52991 inhabitants)
91 Km SE of Viterbo (67173 inhabitants)
92 Km SW of L'Aquila (69753 inhabitants)
93 Km S of Terni (111501 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 2.1
ML-VAX 1.7
1991-01-12
12:44:02
41.724 12.677 10 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 134109
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1991-01-12 12:44:02 ± 0.303
Latitude 41.7240 ± 0.0130
Longitude 12.6770 ± 0.0199
Depth (km) 10 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 134109

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) 2197.1
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 304
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) 0.1
Epicentral distance of station closest to the epicenter (degree) 0.00040
Epicentral distance of station farthest from the epicenter (degree) 0.00591
Number of stations at which the event was observed 4
Number of stations from which data was used for origin computation 4
Magnitudes information

Md:2.1

Field Value
Value 2.1
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 134109
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 19:05:02

ML:1.7

Field Value
Value 1.7
Uncertainty
Num. used stations 2
Type of magnitude ML
Reference to an origin 134109
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
--.MNS.Z. 1991-01-12T12:44:25.00 10.0 undecidable manual SG 0 0.6549 -0.34 0.1
--.MNS.Z. 1991-01-12T12:44:15.80 10.0 undecidable manual PG 0 0.6549 0.23 0.5
--.CP9.Z. 1991-01-12T12:44:12.36 10.0 undecidable manual SG 55 0.2442 0.28 0.2
--.RMP.Z. 1991-01-12T12:44:07.24 10.0 undecidable manual SG 12 0.0777 0.05 0.8
--.CP9.Z. 1991-01-12T12:44:07.73 10.0 undecidable manual PG 55 0.2442 -0.19 1.2
--.RDP.Z. 1991-01-12T12:44:06.95 10.0 undecidable manual SG? 40 0.0444 0.73 0
--.RMP.Z. 1991-01-12T12:44:05.90 10.0 undecidable manual PG 12 0.0777 0 2.1
--.RDP.Z. 1991-01-12T12:44:04.51 10.0 undecidable manual PG 40 0.0444 -0.02 2.1
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