Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of ML 1.9 on date 18-08-2020 and time 18:34:30 (Italy) in region 7 km NW Colonna (RM)

A magnitude ML 1.9 earthquake occured in region: 7 km NW Colonna (RM), on

  • 18-08-2020 16:34:30 (UTC)
  • 18-08-2020 18:34:30 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 41.8810, 12.7030 at 7 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
Colonna RM 7 4287 4287
Monte Porzio Catone RM 7 8693 12980
Frascati RM 8 22087 35067
Monte Compatri RM 9 11978 47045
Gallicano nel Lazio RM 10 6334 53379
San Cesareo RM 11 15153 68532
Grottaferrata RM 11 20327 88859
Rocca Priora RM 11 11962 100821
Zagarolo RM 12 17843 118664
Ciampino RM 12 38412 157076
Tivoli RM 12 56533 213609
Marino RM 13 43026 256635
Rocca di Papa RM 13 17034 273669
Guidonia Montecelio RM 14 88673 362342
Fonte Nuova RM 15 32562 394904
San Gregorio da Sassola RM 15 1619 396523
Castel Gandolfo RM 15 8997 405520
Casape RM 16 744 406264
Poli RM 16 2418 408682
Palestrina RM 16 21672 430354
Castel San Pietro Romano RM 16 902 431256
Sant'Angelo Romano RM 17 5018 436274
Albano Laziale RM 17 41715 477989
Castel Madama RM 17 7399 485388
Nemi RM 18 1943 487331
Mentana RM 18 22921 510252
Ariccia RM 18 19407 529659
Roma RM 18 2864731 3394390
Marcellina RM 18 7280 3401670
Labico RM 19 6379 3408049
San Polo dei Cavalieri RM 19 2992 3411041
Genzano di Roma RM 19 23970 3435011

Municipalities with at least 50000 inhabitants

An earthquake occurred to
12 Km SW of Tivoli (56533 inhabitants)
14 Km S of Guidonia Montecelio (88673 inhabitants)
18 Km E of Roma (2864731 inhabitants)
22 Km N of Velletri (53303 inhabitants)
29 Km NE of Pomezia (62966 inhabitants)
32 Km N of Aprilia (73446 inhabitants)
40 Km E of Fiumicino (78395 inhabitants)
48 Km N of Anzio (54211 inhabitants)
49 Km NW of Latina (125985 inhabitants)
76 Km S of Terni (111501 inhabitants)
77 Km SE of Viterbo (67173 inhabitants)
78 Km SW of L'Aquila (69753 inhabitants)
79 Km E of Civitavecchia (52991 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 		ML 1.9 2020-08-18
16:34:30		 41.881 12.7028 7 2020-11-19
12:37:03		 Bollettino Sismico Italiano INGV 83590501
Reviewed
Rev100 		Md 1.3 2020-08-18
16:34:30		 41.8777 12.7052 8 2020-08-18
16:41:05		 Sala Sismica INGV-Roma 82119441
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2020-08-18 16:34:30 ± 0.3
Latitude 41.8810 ± 0.0054
Longitude 12.7028 ± 0.0157
Depth (km) 7 ± 2 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 83590501

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1288
Semi-minor axis of confidence ellipse (meter) 249
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 279
Circular confidence region, given by single value of horizontal uncertainty (meter) 1290.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 153
Number of associated phases, regardless of their use for origin computation 39
Number of defining phases 10
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.27
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.14479
Number of stations at which the event was observed 32
Number of stations from which data was used for origin computation 5
Magnitudes information

ML:1.9

Field Value
Value 1.9
Uncertainty 0.3
Num. used stations 8
Type of magnitude ML
Reference to an origin 83590501
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2020-10-07 17:42:42

Md:1.3

Field Value
Value 1.3
Uncertainty 0.7
Num. used stations 4
Type of magnitude Md
Reference to an origin 82119441
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2020-08-18 16:41:05
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
IV.SALB.HHZ. 2020-08-18T16:35:25.14 3.0 undecidable manual Sn -4.96 0
IV.SCHR.EHZ. 2020-08-18T16:35:19.07 3.0 undecidable manual Sn -1.79 0
IT.ACQ.HGZ. 2020-08-18T16:35:13.56 3.0 undecidable manual Sn 2.45 0
IV.PANTE.HHZ. 2020-08-18T16:35:13.82 3.0 undecidable manual Pn 0.48 0
IV.VENT.EHZ. 2020-08-18T16:35:11.13 3.0 undecidable manual Sg 13.64 0
MN.KEK.HHZ. 2020-08-18T16:35:09.64 3.0 undecidable manual Pn 11.36 0
IV.ZONE.HHZ. 2020-08-18T16:35:06.28 3.0 undecidable manual Sg 13.62 0
XK.GIZZ.HHZ. 2020-08-18T16:35:02.84 3.0 negative manual Pg 16.440001 0
IV.MTMR.EHZ. 2020-08-18T16:34:59.33 3.0 undecidable manual Sn 1.79 0
GU.BLANC.HHZ. 2020-08-18T16:34:57.28 3.0 undecidable manual Pg 14.42 0
IV.CAR1.HHZ. 2020-08-18T16:34:56.75 3.0 undecidable manual Pg 13.87 0
GU.ENR.HHZ. 2020-08-18T16:34:55.35 3.0 undecidable manual Pg 20.65 0
XK.SELL.HHZ. 2020-08-18T16:34:53.13 3.0 undecidable manual Pn 5.18 0
GU.GRAM.HHZ. 2020-08-18T16:34:49.49 3.0 undecidable manual Sg 6.78 0
IV.PTRP.HHZ. 2020-08-18T16:34:43.06 3.0 undecidable manual Pg 16.85 0
IV.MTCE.HHZ. 2020-08-18T16:34:36.62 0.3 undecidable manual S 12 16.0728 113 0.22 73
IV.RIBO.EHZ.01 2020-08-18T16:34:36.88 3.0 undecidable manual Sg 4.31 0
IV.SAMA.EHZ. 2020-08-18T16:34:36.16 0.3 undecidable manual S 219 14.3745 116 0.27 72
OX.CIMO.HHZ. 2020-08-18T16:34:36.50 3.0 undecidable manual Sn 0.02 0
IV.VIVA.HHN. 2020-08-18T16:34:36.96 0.6 undecidable manual S 159 15.5733 114 0.72 42
IV.RDP.HHZ. 2020-08-18T16:34:35.21 0.6 undecidable manual S 177 13.3755 117 -0.36 48
IV.SAMA.EHZ. 2020-08-18T16:34:33.52 0.3 undecidable manual P 219 14.3745 116 -0.02 76
IV.VIVA.HHN. 2020-08-18T16:34:33.80 0.3 undecidable manual P 159 15.5733 114 0.06 76
IV.RDP.HHZ. 2020-08-18T16:34:33.25 0.3 undecidable manual P 177 13.3755 117 -0.1 75
IV.RMP.HHZ. 2020-08-18T16:34:33.76 0.3 undecidable manual S 179 7.6812 132 -0.16 75
IV.MTCE.HHZ. 2020-08-18T16:34:33.68 0.1 undecidable manual P 12 16.0728 113 -0.16 99
IV.RMP.HHZ. 2020-08-18T16:34:32.24 0.1 undecidable manual P 179 7.6812 132 -0.17 100
IV.SCHR.EHZ. 2020-08-18T16:34:27.95 3.0 positive manual Pn -2.35 0
IV.CMPR.HHZ. 2020-08-18T16:34:25.78 3.0 undecidable manual Pn -0.2 0
IV.CAPR.HNZ. 2020-08-18T16:34:24.16 3.0 undecidable manual Pg 9.06 0
IV.MTMR.EHZ. 2020-08-18T16:34:15.50 3.0 undecidable manual Pn -1.7 0
IV.IMOL.HNZ. 2020-08-18T16:34:11.85 3.0 undecidable manual Sg -1.35 0
IV.VCEL.EHZ. 2020-08-18T16:33:57.26 3.0 negative manual Pg 2.12 0
IV.RONT.HHZ. 2020-08-18T16:33:56.75 3.0 positive manual Pn 1.7 0
IV.BRSN.EHZ. 2020-08-18T16:33:48.45 3.0 negative manual P -0.39 0
IV.OFFI.HHZ. 2020-08-18T16:33:48.40 3.0 positive manual P 0.68 0
IV.CPGN.EHZ. 2020-08-18T16:33:45.68 3.0 undecidable manual P -1.05 0
IV.PE3.EHZ. 2020-08-18T16:33:45.23 3.0 negative manual P 0.1 0
IV.NARO.HHZ. 2020-08-18T16:33:43.45 3.0 undecidable manual P -1.35 0
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.RMP.HHE. ML:2.2 0.003094672 0.1408 AML other m 2020-08-18T16:34:33.98
IV.RMP.HHN. ML:2.5 0.006191520000000001 0.1536 AML other m 2020-08-18T16:34:34.03
IV.RDP.HHN. ML:2.0 0.0011724475 0.3968 AML other m 2020-08-18T16:34:36.89
IV.RDP.HHE. ML:1.8 0.0007405991 0.4864 AML other m 2020-08-18T16:34:37.68
IV.MTCE.HHE. ML:1.2 0.0001763835 0.3584 AML other m 2020-08-18T16:34:37.00
IV.MTCE.HHN. ML:1.4 0.00023229265 0.3072 AML other m 2020-08-18T16:34:36.94
IV.VIVA.HHE. ML:2.0 0.0010978852500000001 0.2816 AML other m 2020-08-18T16:34:40.06
IV.VIVA.HHN. ML:2.0 0.00096909155 0.2432 AML other m 2020-08-18T16:34:38.57
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