Earthquake with magnitude of ML 2.5 on date 27-08-2021 and time 15:47:46 (Italy) in region 1 km N Savignone (GE)

A magnitude ML 2.5 earthquake occured in region: 1 km N Savignone (GE), on

  • 27-08-2021 13:47:46 (UTC)
  • 27-08-2021 15:47:46 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 44.571, 8.988 at 8 km depth.

The earthquake was located by: Sala Sismica INGV-Roma.

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
Savignone GE 1 3205 3205
Crocefieschi GE 3 548 3753
Busalla GE 3 5563 9316
Casella GE 4 3144 12460
Ronco Scrivia GE 5 4417 16877
Vobbia GE 5 409 17286
Valbrevenna GE 6 798 18084
Mignanego GE 8 3675 21759
Montoggio GE 8 2067 23826
Serra Riccò GE 8 7885 31711
Isola del Cantone GE 9 1540 33251
Fraconalto AL 9 336 33587
Mongiardino Ligure AL 10 165 33752
Sant'Olcese GE 10 5906 39658
Campomorone GE 10 6996 46654
Ceranesi GE 10 3875 50529
Roccaforte Ligure AL 12 136 50665
Voltaggio AL 13 738 51403
Davagna GE 14 1884 53287
Grondona AL 14 510 53797
Cabella Ligure AL 14 528 54325
Torriglia GE 15 2311 56636
Arquata Scrivia AL 15 6409 63045
Propata GE 16 142 63187
Carrosio AL 16 510 63697
Albera Ligure AL 16 325 64022
Carrega Ligure AL 16 84 64106
Rocchetta Ligure AL 16 200 64306
Bargagli GE 16 2708 67014
Cantalupo Ligure AL 17 527 67541
Vignole Borbera AL 17 2182 69723
Bosio AL 18 1227 70950
Borghetto di Borbera AL 18 1966 72916
Genova GE 18 586655 659571
Rondanina GE 18 62 659633
Lumarzo GE 18 1535 661168
Serravalle Scrivia AL 19 6128 667296
Gavi AL 20 4614 671910
Fascia GE 20 81 671991
Mornese AL 20 737 672728
Stazzano AL 20 2486 675214

Municipalities with at least 50000 inhabitants

An earthquake occurred to
18 Km N of Genova (586655 inhabitants)
48 Km SE of Alessandria (93943 inhabitants)
50 Km NE of Savona (61345 inhabitants)
70 Km S of Pavia (72576 inhabitants)
72 Km SE of Asti (76202 inhabitants)
77 Km SW of Piacenza (102191 inhabitants)
84 Km S of Vigevano (63310 inhabitants)
84 Km NW of La Spezia (93959 inhabitants)
Recent and historical seismicity

These maps show the seismicity for different time windows. The earthquake locations reported in these maps are determined in quasi real-time by the personnel on duty in the seismic surveillance center of INGV in Rome. Note that the earthquake source parameters (hypocentral location and magnitude) are the best estimates obstained with the available data and they are adjourned as additional data become available. The source parameters obtained by the personnel on duty are then revised by the group in charge of the INGV Seismic Bulletin (Bollettino Sismico Italiano dell’INGV).

Earthquakes of the 3 days preceding this event

Earthquakes of the 3 days preceding this event

This map reports the earthquake epicenters located in the 72 hours (3 days) preceding the time of the current earthquake occurrence, using the data acquired by the Italian National Seismic Network and by other collaborating networks in Italy and in the neighbouring countries. The radius of the circle representing the earthquake on the map scales with magnitude. The color depends on the time of occurrence of the earthquakes with respect to the time of generation of the map (red = 1 hour; orange = 24 hours; yellow = 72 hours). The open star shows the epicenter of the current earthquake.
Earthquakes of the 90 days preceding this event

Earthquakes of the 90 days preceding this event

This map reports the Magnitudo ≥ 1.0 earthquake epicenters located in the 90 days preceding the time of the current earthquake occurrence, using the data acquired by the Italian National Seismic Network and by other collaborating networks in Italy and in the neighbouring countries. The radii of the circles representing the epicenters on the map scale with magnitude. The color of each circle depends on the time of occurrence of the earthquakes with respect to the time of generation of the map (red = 1 hour; orange = 24 hours; yellow = 72 hours; blue = all other earthquakes). The open star shows 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 reports the Magnitudo ≥ 2.5 earthquake epicenters located using the data acquired by the Italian National Seismic Network and by other collaborating networks in Italy and in the neighbouring countries. The radii of the circles representing the epicenters on the map scale with magnitude. The color of each circle depends on the time of occurrence of the earthquakes with respect to the time of generation of the map (red = 1 hour; orange = 24 hours; yellow = 72 hours; blue = all other earthquakes). The open star shows 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 https://emidius.mi.ingv.it/CPTI15-DBMI15/) with estimated magnitude ≥ 5.0 since 1000 AD until 2014. The epicenters are represented by squares which sides scale with the estimated earthquake magnitude. For earthquakes with magnitude ≥ 6.0, it is also shown the year of occurrence and the magnitude value. The open star shows 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
Preliminary map of the earthquake effects from the web questionnaire

Preliminary map of the earthquake effects from the web questionnaire

This map shows the distribution of the effects of the earthquake on the territory in terms of the MCS (Mercalli-Cancani-Sieberg) intensity scale. The intensities are determined using the data provided in the questionnaire (http://www.haisentitoilterremoto.it/) that are analysed using robust statistical techniques since they are not verified individually. Specifically, the assignment of MCS intensities greater or equal the VI degree of the MCS scale require opportune in situ verification by professional experts. The purple start shows the epicenter. This map is prepared every so often that the population fill in new questionnaires. The number of questionnaires used to determine the map and the date and time of the last adjournment are shown in the upper right part of the panel.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
ML 2.5 2021-08-27
13:47:46
44.5713 8.9883 9 2021-08-27
14:01:11
Sala Sismica INGV-Roma 94709071
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-27 13:47:46 ± 0.11
Latitude 44.5713 ± 0.0063
Longitude 8.9883 ± 0.0063
Depth (km) 9 ± 1 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 94709071

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 689
Semi-minor axis of confidence ellipse (meter) 280
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 167
Circular confidence region, given by single value of horizontal uncertainty (meter) 690
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 91
Number of associated phases, regardless of their use for origin computation 50
Number of defining phases 32
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.33
Epicentral distance of station closest to the epicenter (degree) 0
Epicentral distance of station farthest from the epicenter (degree) 1.50636
Number of stations at which the event was observed 37
Number of stations from which data was used for origin computation 20
Magnitude information

ML:2.5

Field Value
Value 2.5
Uncertainty 0.3
Num. used stations 52
Type of magnitude ML
Reference to an origin 94709071
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-08-27 14:01:11
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.PAOL.HHZ. 2021-08-27T13:49:27.85 3.0 undecidable manual Pg 21.040001 0
IV.ASSB.HHZ. 2021-08-27T13:49:27.27 3.0 undecidable manual Sg 15.08 0
IV.IOCA.HHZ. 2021-08-27T13:49:21.95 3.0 negative manual Pg 17.299999 0
IV.AGLI.HHZ. 2021-08-27T13:49:16.56 3.0 undecidable manual Sn -4.17 0
IV.VBKN.HHZ. 2021-08-27T13:49:07.14 3.0 positive manual Pn -0.51 0
IT.PLTA.HNZ. 2021-08-27T13:49:03.27 3.0 undecidable manual Pn 1.89 0
IV.RIBO.EHZ.01 2021-08-27T13:48:58.93 3.0 undecidable manual Sg 8.14 0
IV.FREG.EHZ. 2021-08-27T13:48:43.66 3.0 positive manual Pg 12.68 0
CH.MMK.HHZ. 2021-08-27T13:48:40.14 3.0 undecidable manual Sg 1.08 0
IV.FRON.EHZ. 2021-08-27T13:48:36.72 3.0 undecidable manual Pn 4.4 0
IV.NARO.HHZ. 2021-08-27T13:48:36.12 3.0 negative manual Pn 5.62 0
GU.TRAV.HHZ. 2021-08-27T13:48:30.12 3.0 undecidable manual S 1.286 2.85 0
GU.MAIM.HHZ. 2021-08-27T13:48:27.03 0.3 undecidable manual S 121 1.2617 50 0.49 53
CH.BNALP.HHZ. 2021-08-27T13:48:26.68 3.0 negative manual Pn 1.23 0
ST.CARE.HNZ. 2021-08-27T13:48:25.66 3.0 undecidable manual Pn 1.97 0
GU.CARD.HHZ. 2021-08-27T13:48:24.33 0.3 undecidable manual S 117 1.1997 50 -0.38 55
GU.MGRO.HHZ. 2021-08-27T13:48:19.44 0.3 undecidable manual S 238 0.9955 50 0.77 51
GU.IMI.HHZ. 2021-08-27T13:48:19.96 0.3 undecidable manual S 230 1.0252 50 0.42 57
IV.MAGA.HHZ. 2021-08-27T13:48:18.60 3.0 undecidable manual Pg 2.34 0
IV.SALO.HHZ. 2021-08-27T13:48:16.35 3.0 undecidable manual P 1.5064 2.7 0
GU.EQUI.HHZ. 2021-08-27T13:48:16.00 0.3 undecidable manual S 116 0.9254 50 -0.59 55
GU.GBOS.HHZ. 2021-08-27T13:48:15.31 0.6 undecidable manual S 248 0.884 50 -0.04 42
IV.PLMA.HHZ. 2021-08-27T13:48:12.48 0.3 undecidable manual S 130 0.8094 50 -0.66 55
GU.TRAV.HHZ. 2021-08-27T13:48:11.84 3.0 undecidable manual P 1.286 1.96 0
GU.RSP.HHZ. 2021-08-27T13:48:11.41 0.3 negative manual P 296 1.3499 50 0.43 53
GU.MAIM.HHZ. 2021-08-27T13:48:10.10 0.3 undecidable manual P 121 1.2617 50 0.63 50
GU.CARD.HHZ. 2021-08-27T13:48:09.27 0.3 undecidable manual P 117 1.1997 50 0.86 47
GU.BHB.HHZ. 2021-08-27T13:48:09.79 0.6 negative manual P 283 1.2537 50 0.46 36
GU.STV.HHZ. 2021-08-27T13:48:09.26 0.6 positive manual P 255 1.2303 50 0.32 37
GU.IMI.HHZ. 2021-08-27T13:48:05.79 0.6 negative manual P 230 1.0252 50 0.36 39
GU.MGRO.HHZ. 2021-08-27T13:48:04.88 0.1 undecidable manual P 238 0.9955 50 -0.04 83
GU.EQUI.HHZ. 2021-08-27T13:48:03.85 1.0 undecidable manual P 116 0.9254 50 0.13 21
IV.PLMA.HHZ. 2021-08-27T13:48:02.11 0.1 undecidable manual P 130 0.8094 50 0.38 81
GU.GBOS.HHZ. 2021-08-27T13:48:02.84 0.6 positive manual P 248 0.884 50 -0.16 41
GU.RORO.HHZ. 2021-08-27T13:48:01.16 0.1 undecidable manual P 235 0.8022 50 -0.46 79
GU.GRAM.HHZ. 2021-08-27T13:48:01.59 1.0 positive manual P 96 0.7716 50 0.51 20
GU.ROTM.HHZ. 2021-08-27T13:47:59.81 3.0 undecidable manual P 1.79 0
GU.PCP.HHZ. 2021-08-27T13:47:58.28 0.3 undecidable manual S 265 0.3166 50 -0.27 68
GU.CANO.HHZ. 2021-08-27T13:47:58.41 0.6 undecidable manual P 236 0.6484 50 -0.56 40
IV.QLNO.HHZ. 2021-08-27T13:47:56.24 0.3 negative manual P 242 0.5207 50 -0.56 61
GU.GORR.HHZ. 2021-08-27T13:47:55.06 0.1 undecidable manual S 81 0.2194 109 -0.03 98
GU.GENL.EHZ. 2021-08-27T13:47:53.51 0.3 undecidable manual S 185 0.1664 115 0.33 70
IV.SARZ.HHZ. 2021-08-27T13:47:53.29 0.3 undecidable manual P 350 0.3004 50 0.26 68
IT.GNV.HGZ. 2021-08-27T13:47:52.65 0.1 undecidable manual S 196 0.1457 118 0.19 96
GU.PCP.HHZ. 2021-08-27T13:47:52.67 0.1 negative manual P 265 0.3166 50 -0.63 83
GU.GORR.HHZ. 2021-08-27T13:47:51.09 0.1 negative manual P 81 0.2194 109 -0.22 95
GU.RNCA.HHZ. 2021-08-27T13:47:50.81 0.1 undecidable manual S 195 0.1034 126 -0.29 95
GU.GENL.EHZ. 2021-08-27T13:47:50.15 0.1 positive manual P 185 0.1664 115 -0.05 98
IT.GNV.HGZ. 2021-08-27T13:47:49.76 0.1 positive manual P 196 0.1457 118 -0.03 99
GU.RNCA.HHZ. 2021-08-27T13:47:48.96 0.1 undecidable manual P 195 0.1034 126 -0.04 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
GU.GENL.EHN. ML:2.7 0.004495 0.92 AML other m 2021-08-27T13:47:54.51
GU.GENL.EHE. ML:2.5 0.00258 0.14 AML other m 2021-08-27T13:47:54.00
GU.GORR.HHN. ML:2.9 0.00446 1.46 AML other m 2021-08-27T13:47:54.24
GU.GORR.HHE. ML:2.9 0.004675 1.38 AML other m 2021-08-27T13:47:56.99
GU.PCP.HHE. ML:2.2 0.000678 1.18 AML other m 2021-08-27T13:47:58.23
GU.PCP.HHN. ML:2.2 0.000691 0.26 AML other m 2021-08-27T13:47:59.44
IV.SARZ.HHN. ML:2.8 0.00282 0.62 AML other m 2021-08-27T13:48:02.51
IV.SARZ.HNN. ML:2.8 0.002675 0.62 AML other m 2021-08-27T13:48:02.51
IV.SARZ.HHE. ML:2.9 0.00356 1.46 AML other m 2021-08-27T13:48:03.97
IV.SARZ.HNE. ML:2.9 0.00349 1.46 AML other m 2021-08-27T13:48:03.98
IV.QLNO.HHN. ML:2.4 0.0004875 0.46 AML other m 2021-08-27T13:48:07.38
IV.QLNO.HHE. ML:2.3 0.0004265 0.5 AML other m 2021-08-27T13:48:08.27
GU.CANO.HHN. ML:2.8 0.0009155 1.16 AML other m 2021-08-27T13:48:10.33
GU.CANO.HHE. ML:2.6 0.000685 1.36 AML other m 2021-08-27T13:48:12.11
GU.RORO.HHN. ML:2.5 0.000406 1.1 AML other m 2021-08-27T13:48:14.67
GU.RORO.HHE. ML:2.6 0.0005045 0.76 AML other m 2021-08-27T13:48:15.76
IV.PLMA.HHE. ML:2.5 0.0003535 0.8 AML other m 2021-08-27T13:48:16.23
IV.PLMA.HHN. ML:2.5 0.000383 0.54 AML other m 2021-08-27T13:48:17.48
GU.GRAM.HHE. ML:2.6 0.0004435 0.3 AML other m 2021-08-27T13:48:18.20
GU.GBOS.HHN. ML:2.4 0.0002775 0.4 AML other m 2021-08-27T13:48:18.03
GU.EQUI.HHE. ML:2.3 0.000184 0.26 AML other m 2021-08-27T13:48:18.84
GU.EQUI.HHN. ML:2.4 0.0002705 0.34 AML other m 2021-08-27T13:48:19.18
GU.GBOS.HHE. ML:2.1 0.000142 0.66 AML other m 2021-08-27T13:48:19.16
GU.IMI.HHE. ML:2.5 0.0002665 1.68 AML other m 2021-08-27T13:48:21.96
GU.GRAM.HHN. ML:2.4 0.000324 0.7 AML other m 2021-08-27T13:48:21.49
GU.MGRO.HHE. ML:2.4 0.000218 1.02 AML other m 2021-08-27T13:48:21.52
GU.MGRO.HHN. ML:2.5 0.0002555 0.7 AML other m 2021-08-27T13:48:21.83
GU.IMI.HHN. ML:2.6 0.000352 0.96 AML other m 2021-08-27T13:48:23.00
GU.CARD.HHE. ML:2.8 0.00036 1.08 AML other m 2021-08-27T13:48:27.08
GU.STV.HHN. ML:2.1 7.8E-5 1.24 AML other m 2021-08-27T13:48:27.37
GU.CARD.HHN. ML:2.6 0.000268 0.4 AML other m 2021-08-27T13:48:28.67
GU.MAIM.HHE. ML:2.3 0.0001175 0.34 AML other m 2021-08-27T13:48:29.07
GU.MAIM.HHN. ML:2.4 0.000152 0.26 AML other m 2021-08-27T13:48:29.35
GU.STV.HHE. ML:2.1 8.155E-5 0.58 AML other m 2021-08-27T13:48:30.38
GU.BHB.HHN. ML:2.2 9.635E-5 1.32 AML other m 2021-08-27T13:48:30.21
GU.TRAV.HHN. ML:2.7 0.0002835 0.24 AML other m 2021-08-27T13:48:31.25
GU.TRAV.HHE. ML:2.8 0.00038 1.04 AML other m 2021-08-27T13:48:31.77
GU.BHB.HNN. ML:2.3 0.0001085 0.8 AML other m 2021-08-27T13:48:31.21
GU.BHB.HHE. ML:2.2 9.89E-5 0.5 AML other m 2021-08-27T13:48:32.67
GU.BHB.HNE. ML:2.3 0.000113 1.08 AML other m 2021-08-27T13:48:32.14
GU.RSP.HHE. ML:2.2 7.835E-5 0.72 AML other m 2021-08-27T13:48:38.41
IV.SALO.HHN. ML:2.6 0.0001485 0.84 AML other m 2021-08-27T13:48:39.61
CH.MMK.HHN. ML:1.8 2.26E-5 0.34 AML other m 2021-08-27T13:48:40.38
GU.RSP.HHN. ML:2.1 6.975E-5 0.32 AML other m 2021-08-27T13:48:40.58
CH.MMK.HHE. ML:1.8 2.45E-5 0.3 AML other m 2021-08-27T13:48:41.32
IV.SALO.HHE. ML:2.4 9.72E-5 0.74 AML other m 2021-08-27T13:48:42.79
IV.MAGA.HHN. ML:2.7 0.0001605 0.28 AML other m 2021-08-27T13:48:46.48
ST.CARE.HNN. ML:4.4 0.00562 0.1 AML other m 2021-08-27T13:48:47.57
ST.CARE.HNE. ML:4.2 0.002845 0.12 AML other m 2021-08-27T13:48:47.74
IV.MAGA.HHE. ML:3 0.0003135 0.54 AML other m 2021-08-27T13:48:48.54
CH.BNALP.HHE. ML:2.1 2.015E-5 1.46 AML other m 2021-08-27T13:49:02.92
CH.BNALP.HHN. ML:2.1 1.9E-5 0.64 AML other m 2021-08-27T13:49:05.06
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Fault Plane solutions

Fault Plane solutions

This map reports the focal mechanisms since 1977 in the region. The white and red beach ball symbols are mechanisms determined using the Regional Centroid Moment Tensor (RCMT, http://www.bo.ingv.it/RCMT) and are determined for earthquakes with magnitude larger than 4.5 in the Euro-Mediterranenan area. Occasionally, when there is a good source-receiver geometry of the target earthquake, the RCMT can be obtained also for earthquakes with magnitude larger than 4.0. The blue and white beach ball symbols indicate the mechanisms obtained from application of the Time Domain Moment Tensor (TDMT, http://terremoti.ingv.it/tdmt.html). This technique is used for M ≥ 3.5. The size of the beach ball sysmbol 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
Waveforms Seismic signals in miniseed + resp format Download