Earthquake with magnitude of Md 2.1 on date 19-05-1987 and time 14:00:22 (Italy) in region 3 km W Gallicano nel Lazio (RM)

A magnitude Md 2.1 earthquake occured in region: 3 km W Gallicano nel Lazio (RM), on

  • 19-05-1987 12:00:22 (UTC)
  • 19-05-1987 14:00:22 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 41.8860, 12.7870 at 8 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
Gallicano nel Lazio RM 3 6334 6334
Zagarolo RM 6 17843 24177
Colonna RM 6 4287 28464
San Cesareo RM 7 15153 43617
San Gregorio da Sassola RM 8 1619 45236
Casape RM 9 744 45980
Tivoli RM 9 56533 102513
Poli RM 9 2418 104931
Monte Compatri RM 10 11978 116909
Monte Porzio Catone RM 10 8693 125602
Palestrina RM 10 21672 147274
Castel San Pietro Romano RM 10 902 148176
Rocca Priora RM 10 11962 160138
Castel Madama RM 12 7399 167537
Frascati RM 12 22087 189624
Guidonia Montecelio RM 14 88673 278297
Labico RM 14 6379 284676
Rocca di Cave RM 14 377 285053
Capranica Prenestina RM 14 351 285404
Cave RM 14 11287 296691
Pisoniano RM 15 770 297461
Grottaferrata RM 15 20327 317788
San Polo dei Cavalieri RM 15 2992 320780
Rocca di Papa RM 15 17034 337814
Marcellina RM 15 7280 345094
Ciciliano RM 15 1336 346430
Valmontone RM 16 15959 362389
San Vito Romano RM 16 3273 365662
Genazzano RM 17 6036 371698
Marino RM 17 43026 414724
Sambuci RM 17 925 415649
Vicovaro RM 17 4019 419668
Cerreto Laziale RM 18 1118 420786
Sant'Angelo Romano RM 18 5018 425804
Ciampino RM 18 38412 464216
Lariano RM 18 13432 477648
Gerano RM 18 1263 478911
Fonte Nuova RM 19 32562 511473
Castel Gandolfo RM 19 8997 520470
Saracinesco RM 19 185 520655
Nemi RM 19 1943 522598
Artena RM 20 14276 536874
Mandela RM 20 917 537791
Rocca Santo Stefano RM 20 975 538766

Municipalities with at least 50000 inhabitants

An earthquake occurred to
9 Km S of Tivoli (56533 inhabitants)
14 Km SE of Guidonia Montecelio (88673 inhabitants)
22 Km N of Velletri (53303 inhabitants)
25 Km E of Roma (2864731 inhabitants)
34 Km NE of Pomezia (62966 inhabitants)
34 Km NE of Aprilia (73446 inhabitants)
47 Km E of Fiumicino (78395 inhabitants)
47 Km N of Latina (125985 inhabitants)
50 Km N of Anzio (54211 inhabitants)
72 Km SW of L'Aquila (69753 inhabitants)
76 Km S of Terni (111501 inhabitants)
82 Km SE of Viterbo (67173 inhabitants)
85 Km E of Civitavecchia (52991 inhabitants)
Recent and historical seismicity

These maps show the seismic activity in different time intervals, before the seismic event to which they refer. Data reported in the first two maps come from the analysis carried out in real time by the personnel of the INGV Operating Rooms, immediately after each earthquake. The third map shows data from 1985 to the date of the earthquake: the locations are reviewed by the seismological analysts of the INGV Italian Seismic Bulletin (Bollettino Sismico Italiano dell’INGV). The localization parameters (hypocentral coordinates and magnitude) are the best possible estimate with the data available to the INGV, but are constantly updated according to further data that become available. The location and magnitude parameters, subsequently reviewed by seismological analysts, may vary.

Earthquakes of the 3 days preceding this event

Earthquakes of the 3 days preceding this event

This map shows the earthquake epicenters with magnitude ≥ 0.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, in the 72 hours preceding this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes of the 90 days preceding this event

Earthquakes of the 90 days preceding this event

This map shows the earthquake epicenters with magnitude ≥ 2.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, in the 90 days preceding this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes from 1985 to the date of the event

Earthquakes from 1985 to the date of the event

This map shows the earthquake epicenters with magnitude ≥ 3.0, localized with data recorded by the National Seismic Network and other collaborative networks both in Italy and in neighboring countries, from 1985 to the date of this event. The size of the circle indicates the different classes of magnitude. The colors indicate the different time intervals preceding the seismic event. The black and white star is the epicenter of the current earthquake.
Earthquakes since 1000 AD until 2019

Earthquakes since 1000 AD until 2019

This map shows the epicenters of the historical earthquakes catalogue CPT15 (Catalogo Parametrico dei Terremoti Italiani, 2015 version 3.0, https://doi.org/10.13127/cpti/cpti15.3) since 1000 AD until 2019. The size of the square indicates the different classes of magnitude. For earthquakes with magnitude ≥ 6.0, it is also shown the year of occurrence and the magnitude value. The black and white star is the epicenter of the current earthquake.
Seismic hazard

Seismic hazard maps provide probabilistic estimates of the earthquake ground shaking exceeding a given threshold in a given geographic region within a given time window. Thus, it is not a deterministic prediction - a target that may be never reached given the complexity of the earthquake physical phenomenon - nor of the maximum expected earthquake since this has extremely low probabilities to occur.

In 2004, it was published the seismic hazard map of Italy (http://zonesismiche.mi.ingv.it) that provides a picture of the most hazardous geographic regions. The seismic hazard map of Italy (GdL MPS, 2004; rif. Ordinanza PCM del 28 aprile 2006, n. 3519, All. 1b) provides the 10% probability of exceedance in 50 years of the horizontal acceleration at rock sites (i.e., Vs30>800 m/s; cat. A, 3.2.1 of the D.M. 14.09.2005).

The colours indicate the various values of the ground acceleration that have 10% to be exceeded within 50 years. In general, the colours associated to low values of acceleration refer to areas that are less hazardous and stronger earthquakes repeat less frequently although they may still occur.

Seismic hazard map

Seismic hazard map

This map shows the seismic hazard map of Italy for the region where the earthquake occurred.
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 1987-05-19
12:00:22
41.886 12.787 8 2013-07-15
08:40:51
Bollettino Sismico Italiano INGV 47319
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 1987-05-19 12:00:22 ± 0.563
Latitude 41.8860 ± 0.0405
Longitude 12.7870 ± 0.0233
Depth (km) 8 ± 3 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-VAX
Event type earthquake
Origin ID 47319

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) 4895.8
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 241
Number of associated phases, regardless of their use for origin computation 6
Number of defining phases 6
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.2
Epicentral distance of station closest to the epicenter (degree) 0.00081
Epicentral distance of station farthest from the epicenter (degree) 0.00121
Number of stations at which the event was observed 3
Number of stations from which data was used for origin computation 3
Magnitude information

Md:2.1

Field Value
Value 2.1
Uncertainty
Num. used stations 3
Type of magnitude Md
Reference to an origin 47319
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2013-01-04 17:46:24
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
--.RDP.Z. 1987-05-19T12:00:28.00 10.0 undecidable manual SG? 202 0.0012 -0.55 0
--.CP9.Z. 1987-05-19T12:00:28.50 10.0 undecidable manual SG 101 0.0011 0.37 0.2
--.RMP.Z. 1987-05-19T12:00:27.00 10.0 undecidable manual SG 220 0.0008 -0.25 0.7
--.RDP.Z. 1987-05-19T12:00:26.00 10.0 undecidable manual PG 202 0.0012 0 1.9
--.CP9.Z. 1987-05-19T12:00:25.50 10.0 undecidable manual PG 101 0.0011 -0.26 1.1
--.RMP.Z. 1987-05-19T12:00:25.50 10.0 undecidable manual PG 220 0.0008 0.25 1.1
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Fault Plane solutions

Fault Plane solutions

The map reports the fault plane solutions for earthquakes in the region from 1977 to the date of this event. Red moment tensors are determined using the Regional Centroid Moment Tensor technique (RCMT, http://www.bo.ingv.it/RCMT) applied for earthquakes with magnitude larger than 4.5 in the Euro-Mediterranenan area. Occasionally, when a station azimuthal coverage exists RCMTs can be obtained also for earthquakes with magnitude down to 4.0. The gray moment tensors are obtained with the Time Domain Moment Tensor method (TDMT, http://terremoti.ingv.it/tdmt). This technique is applied to earthquakes with magnitude ML greater than 3.2, when it is possible. The size of symbols scales with the calculated moment magnitude Mw.
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download