Earthquake with magnitude of ML 2.1 on date 18-08-2021 and time 02:59:07 (Italy) in region 2 km NW Sant'Alfio (CT)

A magnitude ML 2.1 earthquake occured in region: 2 km NW Sant'Alfio (CT), on

  • 18-08-2021 00:59:07 (UTC)
  • 18-08-2021 02:59:07 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 37.7560, 15.1250 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
Sant'Alfio CT 2 1582 1582
Milo CT 4 1087 2669
Giarre CT 6 27659 30328
Mascali CT 6 14282 44610
Zafferana Etnea CT 7 9517 54127
Riposto CT 7 14838 68965
Piedimonte Etneo CT 8 3963 72928
Santa Venerina CT 8 8592 81520
Fiumefreddo di Sicilia CT 9 9623 91143
Linguaglossa CT 10 5403 96546
Calatabiano CT 12 5308 101854
Castiglione di Sicilia CT 14 3215 105069
Gaggi ME 15 3184 108253
Trecastagni CT 16 10910 119163
Motta Camastra ME 16 845 120008
Pedara CT 16 14102 134110
Acireale CT 16 52622 186732
Francavilla di Sicilia ME 16 3945 190677
Viagrande CT 16 8563 199240
Giardini-Naxos ME 16 9415 208655
Aci Sant'Antonio CT 17 17984 226639
Aci Catena CT 17 29851 256490
Moio Alcantara ME 17 717 257207
Aci Bonaccorsi CT 18 3524 260731
Taormina ME 18 10960 271691
Graniti ME 18 1492 273183
Castelmola ME 18 1088 274271
Nicolosi CT 18 7463 281734
Malvagna ME 19 733 282467
Valverde CT 20 7840 290307
San Giovanni la Punta CT 20 23060 313367

Municipalities with at least 50000 inhabitants

An earthquake occurred to
16 Km N of Acireale (52622 inhabitants)
28 Km N of Catania (314555 inhabitants)
60 Km SW of Reggio di Calabria (183035 inhabitants)
62 Km SW of Messina (238439 inhabitants)
79 Km N of Siracusa (122291 inhabitants)
98 Km E of Caltanissetta (63360 inhabitants)
99 Km NE of Ragusa (73313 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
ML 2.1 2021-08-18
00:59:07
37.7562 15.1252 10 2021-12-29
11:12:24
Bollettino Sismico Italiano INGV 94919591
Reviewed
Rev200
ML 2.0 2021-08-18
00:59:07
37.752 15.1 9 2021-12-10
11:13:27
Sala Operativa INGV_OE (Catania) 94316781
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-18 00:59:07 ± 0.06
Latitude 37.7562 ± 0.0036
Longitude 15.1252 ± 0.0068
Depth (km) 10 ± 0 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type earthquake
Origin ID 94919591

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 577
Semi-minor axis of confidence ellipse (meter) 326
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 291
Circular confidence region, given by single value of horizontal uncertainty (meter) 580.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 109
Number of associated phases, regardless of their use for origin computation 53
Number of defining phases 41
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.28
Epicentral distance of station closest to the epicenter (degree) 0.00000
Epicentral distance of station farthest from the epicenter (degree) 0.81029
Number of stations at which the event was observed 35
Number of stations from which data was used for origin computation 26
Magnitudes information

ML:2.1

Field Value
Value 2.1
Uncertainty 0.3
Num. used stations 36
Type of magnitude ML
Reference to an origin 94919591
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-12-10 11:13:17

ML:2.0

Field Value
Value 2.0
Uncertainty 0.3
Num. used stations
Type of magnitude ML
Reference to an origin 94316781
Agency INGV
Autore Sala Operativa INGV_OE (Catania)
Time of creation (UTC) 2021-08-18 01:06:01
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.HAVL.HHZ. 2021-08-18T00:59:33.93 0.3 undecidable manual S 180 0.7959 50 0.19 62
IV.SSY.HHZ. 2021-08-18T00:59:28.11 0.3 undecidable manual S 184 0.5989 50 0.19 65
IV.MSRU.HHE. 2021-08-18T00:59:27.75 0.3 undecidable manual S 31 0.5909 50 0.1 66
IV.HAGA.HHE. 2021-08-18T00:59:24.28 0.6 undecidable manual S 177 0.4712 50 0.16 45
IV.HCRL.HHE. 2021-08-18T00:59:24.43 0.3 undecidable manual S 189 0.4784 50 0.1 68
IV.PLLN.EHZ. 2021-08-18T00:59:22.55 0.3 undecidable manual P 287 0.8103 50 -0.28 61
IV.HLNI.HHZ. 2021-08-18T00:59:22.99 0.3 undecidable manual S 206 0.4542 50 -0.62 60
IV.MPNC.HHN. 2021-08-18T00:59:22.78 1.0 undecidable manual S 25 0.4299 50 -0.1 23
IV.HAVL.HHZ. 2021-08-18T00:59:22.43 0.3 undecidable manual P 180 0.7959 50 -0.16 63
IV.ESCV.HHN. 2021-08-18T00:59:19.65 3.0 undecidable manual S 1.32 0
IV.MSRU.HHE. 2021-08-18T00:59:19.18 0.1 undecidable manual P 31 0.5909 50 0.11 88
IV.MSFR.HHZ. 2021-08-18T00:59:18.21 0.6 undecidable manual P 304 0.5045 50 0.62 39
IV.MTTG.HHE. 2021-08-18T00:59:18.38 0.1 undecidable manual P 61 0.5162 50 0.58 80
IV.SSY.HHZ. 2021-08-18T00:59:18.96 0.3 undecidable manual P 184 0.5989 50 -0.26 64
IT.LNT.HGZ. 2021-08-18T00:59:17.21 0.1 undecidable manual P 192 0.4775 50 0.07 91
IV.EPZF.HHN. 2021-08-18T00:59:17.24 3.0 undecidable manual S -0.41 0
IV.HAGA.HHE. 2021-08-18T00:59:17.33 0.1 undecidable manual P 177 0.4712 50 0.3 87
IV.GALF.HHZ. 2021-08-18T00:59:17.43 0.3 undecidable manual P 264 0.4434 50 0.87 54
IV.AIO.HHN. 2021-08-18T00:59:17.10 0.6 undecidable manual S 22 0.2311 110 0.25 46
IV.HCRL.HHE. 2021-08-18T00:59:16.87 0.3 undecidable manual P 189 0.4784 50 -0.28 65
IV.HLNI.HHZ. 2021-08-18T00:59:16.29 0.3 undecidable manual P 206 0.4542 50 -0.45 63
IV.MPNC.HHN. 2021-08-18T00:59:16.01 0.1 undecidable manual P 25 0.4299 50 -0.31 87
IV.EMSG.HHN. 2021-08-18T00:59:15.38 3.0 undecidable manual S 0.01 0
IV.MUCR.HHZ. 2021-08-18T00:59:14.90 0.3 undecidable manual P 325 0.3489 50 -0.03 70
IV.ESCV.HHZ. 2021-08-18T00:59:13.35 3.0 positive manual P -0.1 0
IV.NOV.HHZ. 2021-08-18T00:59:13.49 0.3 undecidable manual P 2 0.2716 50 -0.13 70
IV.EPIT.HHE. 2021-08-18T00:59:13.32 3.0 undecidable manual S 0.3 0
IV.EMFS.HHZ. 2021-08-18T00:59:13.01 0.3 undecidable manual S 250 0.1070 129 0.38 69
IV.ESML.HHZ. 2021-08-18T00:59:13.07 3.0 positive manual P -0.05 0
IV.ECTS.HHN. 2021-08-18T00:59:12.34 0.3 undecidable manual S 359 0.1259 124 -0.88 57
IV.AIO.HHN. 2021-08-18T00:59:12.55 0.3 undecidable manual P 22 0.2311 110 -0.28 68
IV.EPZF.HHZ. 2021-08-18T00:59:12.86 3.0 positive manual P -0.21 0
IV.EMCN.HHZ. 2021-08-18T00:59:12.29 0.6 undecidable manual S 296 0.0800 137 0.41 46
IV.EMSG.HHZ. 2021-08-18T00:59:11.53 3.0 negative manual P -0.26 0
IV.ECBD.HHZ. 2021-08-18T00:59:11.42 0.6 undecidable manual S 308 0.0387 156 0.44 46
IV.EFIU.HHN. 2021-08-18T00:59:11.94 0.3 undecidable manual S 64 0.0755 139 0.2 72
IV.EVRN.HHN. 2021-08-18T00:59:11.70 0.3 undecidable manual S 173 0.0674 142 0.15 73
IV.ENIC.HHE. 2021-08-18T00:59:10.05 3.0 negative manual P -1.28 0
IV.EMCN.HHZ. 2021-08-18T00:59:10.16 0.1 undecidable manual P 296 0.0800 137 0.2 96
IV.ESVO.HHZ. 2021-08-18T00:59:10.82 0.1 undecidable manual P 277 0.1421 121 -0.22 94
IV.ECTS.HHN. 2021-08-18T00:59:10.58 0.3 undecidable manual P 359 0.1259 124 -0.16 72
IV.EMPL.HHE. 2021-08-18T00:59:10.84 3.0 undecidable manual P -0.61 0
IV.EMFO.HHZ. 2021-08-18T00:59:10.94 0.6 undecidable manual S 234 0.0342 158 0.04 50
IV.EMNR.HHZ. 2021-08-18T00:59:10.64 0.1 undecidable manual P 308 0.0989 131 0.38 92
IV.EPOZ.HHZ. 2021-08-18T00:59:10.65 3.0 negative manual P 0.64 0
IV.ECNE.HHZ. 2021-08-18T00:59:10.25 0.1 undecidable manual P 275 0.0980 131 0.01 99
IV.EMFS.HHZ. 2021-08-18T00:59:10.15 0.1 undecidable manual P 250 0.1070 129 -0.25 94
IV.ESPC.HHZ. 2021-08-18T00:59:09.89 0.1 undecidable manual P 231 0.0998 131 -0.39 91
IV.ECBD.HHZ. 2021-08-18T00:59:09.43 0.1 undecidable manual P 308 0.0387 156 -0.01 100
IV.EFIU.HHN. 2021-08-18T00:59:09.82 0.3 undecidable manual P 64 0.0755 139 -0.07 74
IV.ESAL.HHE. 2021-08-18T00:59:09.22 3.0 negative manual P -0.34 0
IV.EVRN.HHN. 2021-08-18T00:59:09.60 0.3 undecidable manual P 173 0.0674 142 -0.17 72
IV.EMFO.HHZ. 2021-08-18T00:59:09.25 0.1 undecidable manual P 234 0.0342 158 -0.15 97
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.ESAL.HHE. ML:0.0 0.007845 0.28 AML other m 2021-08-18T00:59:11.46
IV.EVRN.HHN. ML:2.7 0.00791 0.14 AML other m 2021-08-18T00:59:12.38
IV.EFIU.HHN. ML:1.8 0.0009379999999999999 0.58 AML other m 2021-08-18T00:59:13.07
IV.EPIT.HHN. ML:2.7 0.00675 0.68 AML other m 2021-08-18T00:59:13.54
IV.EPIT.HHE. ML:2.6 0.00591 0.28 AML other m 2021-08-18T00:59:13.52
IV.EFIU.HHE. ML:1.9 0.001265 1.02 AML other m 2021-08-18T00:59:13.32
IV.ESAL.HHN. ML:0.0 0.0050999999999999995 0.2 AML other m 2021-08-18T00:59:14.06
IV.EVRN.HNN. ML:2.7 0.00771 0.42 AML other m 2021-08-18T00:59:14.58
IV.EPOZ.HHE. ML:2.4 0.0030499999999999998 1.32 AML other m 2021-08-18T00:59:15.71
IV.EVRN.HNE. ML:2.6 0.005945000000000001 0.22 AML other m 2021-08-18T00:59:15.33
IV.EVRN.HHE. ML:2.6 0.006019999999999999 0.24 AML other m 2021-08-18T00:59:15.34
IV.EPOZ.HHN. ML:2.4 0.00303 0.46 AML other m 2021-08-18T00:59:15.63
IV.EMPL.HHE. ML:2.5 0.00271 1.78 AML other m 2021-08-18T00:59:17.07
IV.AIO.HHE. ML:1.8 0.00034899999999999997 1.2 AML other m 2021-08-18T00:59:17.84
IV.EMPL.HHN. ML:2.6 0.003345 0.22 AML other m 2021-08-18T00:59:17.34
IV.EMSG.HHN. ML:2.3 0.001655 0.84 AML other m 2021-08-18T00:59:18.32
IV.EPZF.HHE. ML:2.2 0.0008535 0.36 AML other m 2021-08-18T00:59:19.76
IV.AIO.HHN. ML:1.8 0.0003595 0.28 AML other m 2021-08-18T00:59:19.81
IV.ESML.HNN. ML:1.8 0.00038849999999999996 1.34 AML other m 2021-08-18T00:59:20.89
IV.ESML.HHN. ML:1.8 0.00034599999999999995 1.3 AML other m 2021-08-18T00:59:20.22
IV.EMSG.HHE. ML:2.3 0.00165 0.22 AML other m 2021-08-18T00:59:20.62
IV.ESCV.HHE. ML:2.0 0.000572 0.26 AML other m 2021-08-18T00:59:20.61
IV.NOV.HHE. ML:2.2 0.0007185000000000001 0.32 AML other m 2021-08-18T00:59:21.08
IV.ESML.HNE. ML:1.8 0.00035499999999999996 0.66 AML other m 2021-08-18T00:59:21.88
IV.ESCV.HHN. ML:2.2 0.0008085 0.22 AML other m 2021-08-18T00:59:22.24
IV.EPZF.HHN. ML:2.0 0.0006525 0.32 AML other m 2021-08-18T00:59:22.35
IV.ESML.HHE. ML:1.8 0.0003845 0.54 AML other m 2021-08-18T00:59:22.46
IV.MUCR.HHE. ML:1.6 0.000161 0.36 AML other m 2021-08-18T00:59:22.87
IV.NOV.HHN. ML:2.0 0.0005415 0.58 AML other m 2021-08-18T00:59:23.49
IV.HLNI.HHE. ML:1.4 0.00006795 0.7 AML other m 2021-08-18T00:59:24.64
IV.HCRL.HHE. ML:1.8 0.0001555 0.78 AML other m 2021-08-18T00:59:25.49
IV.MPNC.HHE. ML:2.0 0.00026000000000000003 0.84 AML other m 2021-08-18T00:59:26.42
IV.HCRL.HHN. ML:1.8 0.00013450000000000002 0.94 AML other m 2021-08-18T00:59:27.02
IV.MUCR.HHN. ML:1.6 0.000156 1.56 AML other m 2021-08-18T00:59:27.91
IV.HLNI.HHN. ML:1.5 0.00007384999999999999 0.66 AML other m 2021-08-18T00:59:27.19
IV.MPNC.HHN. ML:2.0 0.0002465 0.54 AML other m 2021-08-18T00:59:28.26
IV.GALF.HHE. ML:2.3 0.00048350000000000004 1.4 AML other m 2021-08-18T00:59:33.15
IV.GALF.HHN. ML:2.2 0.000409 1.26 AML other m 2021-08-18T00:59:38.96
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
Waveforms Seismic signals in miniseed + resp format Download