Earthquake (quarry blast) with magnitude of ML 1.1 on date 03-08-2021 and time 08:40:50 (Italy) in region 2 km NE Melilli (SR)

A magnitude ML 1.1 (quarry blast) earthquake occured in region: 2 km NE Melilli (SR), on

  • 03-08-2021 06:40:50 (UTC)
  • 03-08-2021 08:40:50 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 37.1980, 15.1430 at 0 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

Event type: quarry blast.

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
Melilli SR 3 13621 13621
Priolo Gargallo SR 6 12091 25712
Augusta SR 8 36305 62017
Sortino SR 10 8690 70707
Solarino SR 11 8091 78798
Floridia SR 13 22762 101560
Carlentini SR 14 17798 119358
Lentini SR 16 24085 143443
Canicattini Bagni SR 19 7109 150552
Ferla SR 20 2523 153075

Municipalities with at least 50000 inhabitants

An earthquake occurred to
20 Km NW of Siracusa (122291 inhabitants)
34 Km S of Catania (314555 inhabitants)
46 Km S of Acireale (52622 inhabitants)
47 Km NE of Ragusa (73313 inhabitants)
51 Km NE of Modica (54633 inhabitants)
60 Km E of Vittoria (63339 inhabitants)
80 Km E of Gela (75827 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 1.1 2021-08-03
06:40:50
37.1982 15.1427 1 2021-12-29
11:12:53
Bollettino Sismico Italiano INGV 98463451
Reviewed
Rev100
ML 1.3 2021-08-03
06:40:49
37.1693 15.0902 17 2021-08-03
06:49:31
Sala Sismica INGV-Roma 93595981
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-03 06:40:50 ± 0.1
Latitude 37.1982 ± 0.0045
Longitude 15.1427 ± 0.0102
Depth (km) 1 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type quarry blast
Origin ID 98463451

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 890
Semi-minor axis of confidence ellipse (meter) 520
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 259
Circular confidence region, given by single value of horizontal uncertainty (meter) 890.0
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 143
Number of associated phases, regardless of their use for origin computation 5
Number of defining phases 5
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.16
Epicentral distance of station closest to the epicenter (degree) 0.06835
Epicentral distance of station farthest from the epicenter (degree) 0.23922
Number of stations at which the event was observed 5
Number of stations from which data was used for origin computation 5
Magnitudes information

ML:1.1

Field Value
Value 1.1
Uncertainty 0.2
Num. used stations 8
Type of magnitude ML
Reference to an origin 98463451
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2021-12-13 12:24:38

ML:1.3

Field Value
Value 1.3
Uncertainty 0.1
Num. used stations 8
Type of magnitude ML
Reference to an origin 93595981
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-08-03 06:49:31
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.HAVL.HHZ. 2021-08-03T06:40:55.53 0.3 undecidable manual P 184 0.2392 91 -0.21 94
IV.HSRS.HHZ. 2021-08-03T06:40:53.31 0.3 undecidable manual P 149 0.1232 92 0.15 97
IV.HCRL.HHZ. 2021-08-03T06:40:53.17 0.3 undecidable manual P 314 0.1223 92 0.03 100
IV.SSY.HHZ. 2021-08-03T06:40:52.03 0.3 undecidable manual P 234 0.0683 94 0.08 100
IV.HAGA.HHZ. 2021-08-03T06:40:52.33 0.3 undecidable manual P 6 0.0872 93 -0.05 100
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.SSY.HHN. ML:0.0 0.005373302 0.2592 AML other m 2021-08-03T06:40:55.68
IV.SSY.HHE. ML:0.0 0.0025235665000000003 0.64 AML other m 2021-08-03T06:40:55.65
IV.HSRS.HNE. ML:0.9 0.000108897775 1.3184 AML other m 2021-08-03T06:40:56.12
IV.HSRS.HHN. ML:1.0 0.00011966170000000001 0.3616 AML other m 2021-08-03T06:40:56.63
IV.HCRL.HHN. ML:1.0 0.0001485297 1.0784 AML other m 2021-08-03T06:40:56.34
IV.HSRS.HNN. ML:1.0 0.00014033045 0.688 AML other m 2021-08-03T06:40:57.19
IV.HSRS.HHE. ML:1.0 0.00012148082499999999 0.4224 AML other m 2021-08-03T06:40:57.27
IV.HCRL.HHE. ML:1.2 0.00020912355 0.1792 AML other m 2021-08-03T06:40:57.86
IV.HAVL.HHN. ML:1.4 0.00013900000000000002 0.24 AML other m 2021-08-03T06:41:04.52
IV.HAVL.HHE. ML:1.3 0.000115507005 1.7792 AML other m 2021-08-03T06:41:05.04
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