Earthquake with magnitude of ML 1.9 on date 31-08-2021 and time 07:42:01 (Italy) in region Golfo di Trieste (Trieste, Gorizia, Udine)

A magnitude ML 1.9 earthquake occured in region: Golfo di Trieste (Trieste, Gorizia, Udine), on

  • 31-08-2021 05:42:01 (UTC)
  • 31-08-2021 07:42:01 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) 45.477, 13.233 at 3 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

No Italian municipalities within 20 km distance.

Municipalities with at least 50000 inhabitants

An earthquake occurred to
46 Km W of Trieste (204420 inhabitants)
65 Km S of Udine (99169 inhabitants)
69 Km SE of Pordenone (51229 inhabitants)
70 Km E of Venezia (263352 inhabitants)
80 Km E of Treviso (83731 inhabitants)
Recent and historical seismicity
Seismic hazard
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 1.9 2021-08-31
05:42:01
45.4768 13.2328 3 2021-08-31
05:48:17
Sala Sismica INGV-Roma 94852881
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-31 05:42:01 ± 0.58
Latitude 45.4768 ± 0.0648
Longitude 13.2328 ± 0.0192
Depth (km) 3 ± 8 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV
Event type earthquake
Origin ID 94852881

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 7020
Semi-minor axis of confidence ellipse (meter) 1509
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 173
Circular confidence region, given by single value of horizontal uncertainty (meter) 7020
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 285
Number of associated phases, regardless of their use for origin computation 32
Number of defining phases 14
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.36
Epicentral distance of station closest to the epicenter (degree) 0
Epicentral distance of station farthest from the epicenter (degree) 0.99825
Number of stations at which the event was observed 25
Number of stations from which data was used for origin computation 7
Magnitude information

ML:1.9

Field Value
Value 1.9
Uncertainty 0.5
Num. used stations 12
Type of magnitude ML
Reference to an origin 94852881
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-08-31 05:48:17
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
GU.LSD.HHZ. 2021-08-31T05:44:00.11 3.0 undecidable manual Sn 0.42 0
IV.ACATE.EHZ. 2021-08-31T05:43:59.32 3.0 negative manual Pn -5.56 0
IV.EVRN.HHZ. 2021-08-31T05:43:57.66 3.0 positive manual Pn 0.93 0
GU.MGRO.HHZ. 2021-08-31T05:43:54.89 3.0 undecidable manual Sn -0.62 0
IT.LRNO.HNZ. 2021-08-31T05:43:44.93 3.0 undecidable manual Sn -2.09 0
IV.BRMO.HHZ. 2021-08-31T05:43:13.86 3.0 undecidable manual Sg 4.86 0
IV.VAGA.HHZ. 2021-08-31T05:43:12.86 3.0 negative manual Pg 8.08 0
OT.OT05.EHZ. 2021-08-31T05:43:10.36 3.0 positive manual Pg 4.99 0
IV.CADC.HNZ. 2021-08-31T05:43:09.90 3.0 undecidable manual Sn 1.74 0
IV.FIR.HHZ. 2021-08-31T05:43:09.45 3.0 undecidable manual Sg 1.09 0
GU.RORO.HHZ. 2021-08-31T05:43:03.24 3.0 undecidable manual Pn 0.1 0
CR.ZAG.BHZ. 2021-08-31T05:42:58.02 3.0 undecidable manual Sn -0.97 0
IV.ARVD.HHZ. 2021-08-31T05:42:53.05 3.0 undecidable manual Sn -8.92 0
IV.PE3.EHZ. 2021-08-31T05:42:51.89 3.0 undecidable manual Sn -7.18 0
IV.BRSN.EHZ. 2021-08-31T05:42:45.19 3.0 undecidable manual Sn -4.35 0
GU.CARD.HHZ. 2021-08-31T05:42:43.86 3.0 negative manual Pg 1.23 0
IV.PP3.EHZ. 2021-08-31T05:42:38.31 3.0 positive manual Pg 1.03 0
OX.CIMO.HHZ. 2021-08-31T05:42:34.52 0.1 undecidable manual S 327 0.9982 50 -0.6 83
OX.MPRI.HHZ. 2021-08-31T05:42:29.51 0.1 undecidable manual S 347 0.7824 50 0.79 81
OX.MLN.HHZ. 2021-08-31T05:42:29.63 0.1 undecidable manual S 328 0.7977 50 0.44 91
NI.VINO.HHZ. 2021-08-31T05:42:28.07 0.1 undecidable manual S 2 0.777 50 -0.49 91
OX.CAE.HHZ. 2021-08-31T05:42:28.24 0.1 undecidable manual S 314 0.768 50 -0.06 100
IV.IMOL.HNZ. 2021-08-31T05:42:27.79 3.0 positive manual Pn -2.4 0
OX.DRE.HHZ. 2021-08-31T05:42:27.50 0.1 undecidable manual S 22 0.7527 50 -0.35 94
OX.SABO.HHZ. 2021-08-31T05:42:23.07 0.1 undecidable manual S 29 0.5819 50 0.29 99
OX.CIMO.HHZ. 2021-08-31T05:42:20.38 1.0 undecidable manual P 327 0.9982 50 -0.48 22
OX.MLN.HHZ. 2021-08-31T05:42:17.54 1.0 positive manual P 328 0.7977 50 0.1 25
OX.MPRI.HHZ. 2021-08-31T05:42:17.34 0.6 positive manual P 347 0.7824 50 0.17 49
OX.DRE.HHZ. 2021-08-31T05:42:16.70 1.0 positive manual P 22 0.7527 50 0.04 25
NI.VINO.HHZ. 2021-08-31T05:42:16.86 0.3 negative manual P 2 0.777 50 -0.22 72
OX.CAE.HHZ. 2021-08-31T05:42:16.94 0.6 negative manual P 314 0.768 50 0.01 50
OX.SABO.HHZ. 2021-08-31T05:42:14.02 0.6 negative manual P 29 0.5819 50 0.28 50
Station Magnitude and Amplitude
SCNL mag Generic_amplitude Period Type Category Unit Time_window_reference
OX.SABO.HHN. ML:1.5 6.2E-5 0.18 AML other m 2021-08-31T05:42:23.32
OX.SABO.HHE. ML:1.5 5.395E-5 0.68 AML other m 2021-08-31T05:42:24.44
NI.VINO.HHE. ML:1.6 5.11E-5 0.36 AML other m 2021-08-31T05:42:28.24
NI.VINO.HHN. ML:1.6 5.21E-5 0.2 AML other m 2021-08-31T05:42:28.22
OX.MLN.HHE. ML:1.3 2.705E-5 1.58 AML other m 2021-08-31T05:42:31.94
OX.MLN.HHN. ML:1.2 2.12E-5 1.5 AML other m 2021-08-31T05:42:32.02
IV.IMOL.HNN. ML:3.6 0.001705 0.06 AML other m 2021-08-31T05:42:32.53
IV.FREG.EHE. ML:2.3 0.0002085 0.46 AML other m 2021-08-31T05:42:35.66
IV.FREG.EHN. ML:2.2 0.0001645 0.3 AML other m 2021-08-31T05:42:37.65
IV.IMOL.HNE. ML:3.4 0.001143 0.06 AML other m 2021-08-31T05:42:51.22
GU.CARD.HHN. ML:2.6 6.605E-5 0.06 AML other m 2021-08-31T05:42:57.96
GU.CARD.HHE. ML:2.7 7.515E-5 0.06 AML other m 2021-08-31T05:43:01.98
IV.BRMO.HHE. ML:2.5 5.605E-5 0.08 AML other m 2021-08-31T05:43:16.20
IV.BRMO.HHN. ML:2.5 5.38E-5 0.52 AML other m 2021-08-31T05:43:25.59
GU.LSD.HHN. ML:3.2 5.45E-5 0.06 AML other m 2021-08-31T05:44:03.62
GU.LSD.HHE. ML:3.6 0.0001263 0.16 AML other m 2021-08-31T05:44:03.66
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download