INGVCENTRO​NAZIONALE​TERREMOTI
Sala Sismica

Earthquake (volcanic eruption) with magnitude of ML 2.1 on date 31-12-2017 and time 14:00:08 (Italy) in region 7 km NE Ragalna (CT)

A magnitude ML 2.1 (volcanic eruption) earthquake occured in region: 7 km NE Ragalna (CT), on

  • 31-12-2017 13:00:08 (UTC)
  • 31-12-2017 14:00:08 (UTC +01:00) Italian time

and geographic coordinates (lat, lon) 37.68, 14.98 at 1 km depth.

The earthquake was located by: Bollettino Sismico Italiano INGV.

Event type: volcanic eruption.

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
Ragalna CT 7 3924 3924
Nicolosi CT 9 7463 11387
Pedara CT 10 14102 25489
Belpasso CT 10 28108 53597
Biancavilla CT 11 24007 77604
Santa Maria di Licodia CT 11 7641 85245
Zafferana Etnea CT 11 9517 94762
Trecastagni CT 12 10910 105672
Milo CT 13 1087 106759
San Pietro Clarenza CT 13 7743 114502
Adrano CT 13 36122 150624
Camporotondo Etneo CT 13 5023 155647
Viagrande CT 13 8563 164210
Paternò CT 14 48228 212438
Mascalucia CT 14 31958 244396
Santa Venerina CT 14 8592 252988
Tremestieri Etneo CT 15 20589 273577
Aci Bonaccorsi CT 15 3524 277101
Gravina di Catania CT 16 25838 302939
Aci Sant'Antonio CT 16 17984 320923
San Giovanni la Punta CT 16 23060 343983
Sant'Alfio CT 16 1582 345565
Sant'Agata li Battiati CT 17 9479 355044
Aci Catena CT 17 29851 384895
Bronte CT 17 19172 404067
Valverde CT 17 7840 411907
San Gregorio di Catania CT 18 11966 423873
Misterbianco CT 18 49410 473283
Acireale CT 18 52622 525905
Giarre CT 19 27659 553564
Maletto CT 19 3920 557484
Motta Sant'Anastasia CT 19 12116 569600

Municipalities with at least 50000 inhabitants

An earthquake occurred to
18 Km W of Acireale (52622 inhabitants)
22 Km NW of Catania (314555 inhabitants)
75 Km NW of Siracusa (122291 inhabitants)
75 Km SW of Reggio di Calabria (183035 inhabitants)
76 Km SW of Messina (238439 inhabitants)
84 Km E of Caltanissetta (63360 inhabitants)
87 Km N of Ragusa (73313 inhabitants)
91 Km NE of Vittoria (63339 inhabitants)
94 Km N of Modica (54633 inhabitants)
94 Km NE of Gela (75827 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 last three days (72 hours)

Earthquakes of the last three days (72 hours) *

This map reports the earthquake epicenters located in the past 72 hours (3 days) from the time this page has been generated. 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 last 90 days

Earthquakes of the last 90 days *

This map reports the Magnitudo ≥ 1.0 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 1985

Earthquakes since 1985 *

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.
Significant earthquakes since 1000 AD until 2006

Significant earthquakes since 1000 AD until 2006 *

This map shows the epicenters of the historical earthquakes catalogue CPT11 (Catalogo Parametrico dei Terremoti Italiani, 2011 version) with estimated magnitude ≥ 5.0 since 1000 AD until 2006. 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
Shakemap
Felt maps
The earthquake effects in MCS scale as obtained from the compiled questionnaire

The earthquake effects in MCS scale as obtained from the compiled 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
Rev 1000 ML 2.1 2017-12-31
13:00:08
37.68 14.98 1 2018-09-04
09:10:41
Bollettino Sismico Italiano INGV 54197991
Rev 100 ML 2.2 2017-12-31
13:00:07
37.68 14.94 5 2017-12-31
13:32:53
Sala Sismica INGV-Roma 52935131
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2017-12-31 13:00:08 ± 0.17
Latitude 37.68 ± 0.01
Longitude 14.98 ± 0.01
Depth (km) 1 (operator assigned)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 1000 -> BULLETIN-INGV
Event type volcanic eruption
Origin ID 54197991

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 1260
Semi-minor axis of confidence ellipse (meter) 880
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 281
Circular confidence region, given by single value of horizontal uncertainty (meter) 1260
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 67
Number of associated phases, regardless of their use for origin computation 14
Number of defining phases 14
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.47
Epicentral distance of station closest to the epicenter (degree) 0.00989
Epicentral distance of station farthest from the epicenter (degree) 0.42268
Number of stations at which the event was observed 11
Number of stations from which data was used for origin computation 11
Magnitudes information

ML:2.1

Field Value
Value 2.1
Uncertainty 0.2
Num. used stations 12
Type of magnitude ML
Reference to an origin 54197991
Agency INGV
Autore Bollettino Sismico Italiano INGV
Time of creation (UTC) 2018-07-26 12:17:07

ML:2.2

Field Value
Value 2.2
Uncertainty 0.2
Num. used stations 10
Type of magnitude ML
Reference to an origin 52935131
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2017-12-31 13:32:53
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IV.HAGA.HHN. 2017-12-31T13:00:25.57 0.6 undecidable manual S 161 0.4227 91 0.75 39
IV.NOV.HHZ. 2017-12-31T13:00:17.34 0.3 undecidable manual P 20 0.3651 92 0.7 61
IV.HAGA.HHN. 2017-12-31T13:00:17.09 0.3 undecidable manual P 161 0.4227 91 -0.84 57
IV.GALF.HHZ. 2017-12-31T13:00:16.00 0.3 undecidable manual P 275 0.3274 92 0.2 71
IV.AIO.HHE. 2017-12-31T13:00:16.29 0.3 undecidable manual P 35 0.3498 92 -0.01 73
IV.MUCR.HHZ. 2017-12-31T13:00:16.95 0.3 undecidable manual P 347 0.3678 92 0.25 70
IV.HLNI.HHZ. 2017-12-31T13:00:15.32 0.3 undecidable manual P 194 0.3462 92 -0.91 56
IV.ESML.HHZ. 2017-12-31T13:00:13.24 0.1 undecidable manual S 230 0.1034 96 0.73 84
IV.EPOZ.HHZ. 2017-12-31T13:00:12.62 0.3 undecidable manual P 94 0.1664 94 0.4 70
IV.EPZF.HHZ. 2017-12-31T13:00:11.96 0.3 undecidable manual P 325 0.1691 94 -0.33 71
IV.EMSG.HHZ. 2017-12-31T13:00:11.70 0.1 undecidable manual P 350 0.1376 94 0.1 100
IV.ESML.HHZ. 2017-12-31T13:00:10.33 0.6 undecidable manual P 230 0.1034 96 -0.49 46
IV.ESLN.HHE. 2017-12-31T13:00:09.01 0.3 undecidable manual S 338 0.0099 138 -0.05 78
IV.ESLN.HHE. 2017-12-31T13:00:08.23 0.1 undecidable manual P 338 0.0099 138 -0.6 90
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
IV.ESML.HHN. ML:1.9 0.0014074565 0.22 AML other m 2017-12-31T13:00:13.45
IV.ESML.HHE. ML:2.1 0.0022475595 0.5376 AML other m 2017-12-31T13:00:13.76
IV.EMSG.HHN. ML:2.5 0.003310888 0.4224 AML other m 2017-12-31T13:00:17.62
IV.EMSG.HHE. ML:2.6 0.0046045145 0.66 AML other m 2017-12-31T13:00:17.89
IV.EPOZ.HHE. ML:1.8 0.00065300155 0.54 AML other m 2017-12-31T13:00:20.66
IV.EPOZ.HHN. ML:1.8 0.00063213215 0.58 AML other m 2017-12-31T13:00:21.46
IV.EPZF.HHN. ML:2.2 0.0016256075 1.5 AML other m 2017-12-31T13:00:21.20
IV.EPZF.HHE. ML:2.2 0.0014150485 1.6 AML other m 2017-12-31T13:00:21.15
IV.MUCR.HHE. ML:0 0.0006840209 0.64 AML other m 2017-12-31T13:00:26.04
IV.GALF.HHN. ML:2 0.00043544155 0.6592 AML other m 2017-12-31T13:00:30.84
IV.GALF.HHE. ML:2.1 0.0004779378 0.72 AML other m 2017-12-31T13:00:31.94
IV.MUCR.HHN. ML:0 0.00048464815 0.88 AML other m 2017-12-31T13:00:32.26
TDMT - Time Domain Moment Tensor
Focal Mechanism in the area
Focal Mechanisms

Focal Mechanisms *

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://cnt.rm.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 full SEED format Download