Earthquake with magnitude of Mwp 6.3 on date 05-09-2021 and time 17:51:45 (UTC) in region Tonga Islands [Sea: Tonga]

A magnitude Mwp 6.3 earthquake occured in region: Tonga Islands [Sea: Tonga], on

  • 05-09-2021 17:51:45 (UTC)
  • 05-09-2021 19:51:45 (UTC +02:00) Italian time
  • 06-09-2021 06:51:45 (UTC +13:00) local time in the region of the earthquake (Pacific/Tongatapu)

and geographic coordinates (lat, lon) -21.867, -174.36 at 17 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

No Italian municipalities within 100 km from the epicenter with at least 50000 inhabitants.

Recent and historical seismicity
Seismic hazard
Shakemap

These three maps show the results of the analysis using the software ShakeMap designed to provide the level of ground shaking experienced in a region using the data recorded by seismometers and strong motion instruments and seismological information regarding the attenuation of the wavefield with distance and the site characteristics. The Shakemaps are determined for research purposes to provide fast estimates of the level of ground shaking produced by the earthquake. The maps are calculated automatically and adjourned progressively as more data become available. See http://shakemap.rm.ingv.it/ for additional information.

The red star indicates the epicenter. The red triangles show the stations of the INGV Italian National Seismic Network and the blue triangles those of the Nationa Accelerometric Network of the Dipartimento della Protezione Civile.

Intensity Shakemap

Intensity Shakemap

This map shows the distribution of the istrumentally derived intensities. To this purpose, it is used a conversion relation between ground acceleration and velocity, and the Mercalli Modificata (MMI - Modified Mercalli Intensity) scale. In general, the Mercalli intensity scale relies on the effects that the ground shaking produces as reported by an observer.
Peak ground acceleration Shakemap

Peak ground acceleration Shakemap

This map shows This map shows the distribution of peak ground acceleration expressed as per cent of the acceleration of gravity (i.e., g = 9.81 m/s²).
Peak velocity Shakemap

Peak velocity Shakemap

This map shows the distribution of peak ground velocities expressed in cm/s.
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
mb 5.5
Mwp 6.3

Mwpd 6.4
2021-09-05
17:51:45
-21.8672 -174.36 17 2021-09-05
18:06:57
Sala Sismica INGV-Roma 95081571
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-09-05 17:51:45
Latitude -21.8672
Longitude -174.3600
Depth (km) 17 (from location)
Evaluation mode of Origin automatic
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV-A
Event type earthquake
Origin ID 95081571

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 17012
Semi-minor axis of confidence ellipse (meter) 13263
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 327
Circular confidence region, given by single value of horizontal uncertainty (meter) 13738.5
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 40.9391
Number of associated phases, regardless of their use for origin computation 119
Number of defining phases 119
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 1.91834
Epicentral distance of station closest to the epicenter (degree) 8.24071
Epicentral distance of station farthest from the epicenter (degree) 91.48637
Number of stations at which the event was observed 100
Number of stations from which data was used for origin computation 100
Magnitudes information

Mwp:6.3

Field Value
Value 6.3
Uncertainty 0.1
Num. used stations 29
Type of magnitude Mwp
Reference to an origin 95081571
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-09-05 18:06:57

Mwpd:6.4

Field Value
Value 6.4
Uncertainty 0.1
Num. used stations 27
Type of magnitude Mwpd
Reference to an origin 95081571
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-09-05 18:06:57

mb:5.5

Field Value
Value 5.5
Uncertainty 0.1
Num. used stations 43
Type of magnitude mb
Reference to an origin 95081571
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-09-05 18:06:57
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
IU.HKT.BHZ.00 2021-09-05T18:04:53.75 10.0 negative automatic pP 58 91.4864 -1.51909 0
IU.COLA.BHZ.00 2021-09-05T18:04:52.57 10.0 positive automatic sP 11 89.1105 7.43223 0
GE.LHMI.BHZ. 2021-09-05T18:04:48.37 10.0 positive automatic P 275 90.7331 2.28291 0.0814711
US.EGMT.BHZ.00 2021-09-05T18:04:47.43 10.0 positive automatic PcP 37 90.6093 0.641203 0
G.PEL.BHZ.00 2021-09-05T18:04:45.75 10.0 positive automatic sP 126 88.8616 1.63806 0
G.PEL.BHZ.00 2021-09-05T18:04:41.05 10.0 positive automatic P 126 88.8616 3.58983 0.0932555
US.AMTX.BHZ.00 2021-09-05T18:04:41.65 10.0 positive automatic PcP 52 89.2143 1.0509 0
US.ISCO.BHZ.00 2021-09-05T18:04:40.30 10.0 positive automatic P 46 88.8471 2.55563 0.106027
IU.COLA.BHZ.00 2021-09-05T18:04:38.82 10.0 positive automatic P 11 89.1105 0.275707 0
US.LKWY.BHZ.00 2021-09-05T18:04:38.55 10.0 positive automatic PcP 40 88.3398 1.5735 0
US.BOZ.BHZ.00 2021-09-05T18:04:35.78 10.0 positive automatic P 38 88.1951 1.30489 0.091666
US.SDCO.BHZ.00 2021-09-05T18:04:36.23 10.0 negative automatic P 48 87.8943 3.01761 0.107865
US.BW06.BHZ.00 2021-09-05T18:04:33.60 10.0 positive automatic P 42 87.8661 0.585675 0.0927875
IU.ANMO.BHZ.00 2021-09-05T18:04:33.10 10.0 negative automatic sP 50 85.8199 3.35432 0
US.MSO.BHZ.00 2021-09-05T18:04:31.98 10.0 positive automatic P 37 87.6002 0.395257 0
US.AHID.BHZ.00 2021-09-05T18:04:30.23 10.0 positive automatic PcP 41 86.92 -0.401066 0
US.NEW.BHZ.00 2021-09-05T18:04:28.38 10.0 positive automatic P 34 86.7632 0.942813 0.104022
GE.SNAA.BHZ. 2021-09-05T18:04:26.76 10.0 positive automatic P 177 86.2752 1.70572 0.118584
GT.PLCA.BHZ.00 2021-09-05T18:04:26.98 10.0 positive automatic pP 132 85.6842 -0.913015 0
US.HWUT.BHZ.00 2021-09-05T18:04:25.00 10.0 positive automatic P 42 85.9862 1.20479 0.109345
GT.PLCA.BHZ.00 2021-09-05T18:04:26.90 10.0 positive automatic P 132 85.6842 4.73481 0.123113
US.MVCO.BHZ.00 2021-09-05T18:04:24.05 10.0 positive automatic P 47 85.5772 2.22071 0.0969002
IU.ANMO.BHZ.00 2021-09-05T18:04:25.27 10.0 positive automatic P 50 85.8199 2.29858 0.114105
US.WRAK.BHZ.00 2021-09-05T18:04:25.18 10.0 positive automatic P 22 85.9193 2.01333 0.0573182
US.HLID.BHZ.00 2021-09-05T18:04:22.68 10.0 positive automatic P 39 85.401 1.79553 0.106703
CN.BBB.BHZ. 2021-09-05T18:04:18.13 10.0 positive automatic P 26 84.2996 3.0859 0.138902
US.DUG.BHZ.00 2021-09-05T18:04:17.45 10.0 positive automatic P 42 84.4086 1.60959 0.121845
US.BMO.BHZ.00 2021-09-05T18:04:17.73 10.0 positive automatic P 37 84.5379 1.28314 0.13214
US.HAWA.BHZ.00 2021-09-05T18:04:16.85 10.0 positive automatic P 35 84.3128 1.68363 0.129435
US.ELK.BHZ.00 2021-09-05T18:04:11.63 10.0 positive automatic P 41 83.2336 1.66916 0.136453
G.COYC.BHZ.00 2021-09-05T18:04:11.80 10.0 positive automatic P 136 82.6519 5.19986 0.141124
US.NLWA.BHZ.00 2021-09-05T18:04:10.08 10.0 positive automatic P 32 82.782 2.72856 0.120062
RM.DLV.BHZ. 2021-09-05T18:04:09.27 10.0 positive automatic P 286 82.8355 1.54781 0.142814
US.WUAZ.BHZ.00 2021-09-05T18:04:09.73 10.0 positive automatic P 47 82.7159 2.55782 0.140606
US.WVOR.BHZ.00 2021-09-05T18:04:06.50 10.0 positive automatic P 38 82.2695 1.69899 0.144236
II.KDAK.BHZ.00 2021-09-05T18:04:02.22 10.0 positive automatic P 12 81.6965 0.634989 0.152349
IU.COR.BHZ.00 2021-09-05T18:04:01.25 10.0 positive automatic P 34 81.1372 2.6311 0.13046
US.TPNV.BHZ.00 2021-09-05T18:03:56.70 10.0 positive automatic P 43 80.3289 2.15705 0.174098
IU.YSS.BHZ.00 2021-09-05T18:03:47.35 10.0 positive automatic P 332 78.9303 0.658715 0.176789
BK.CMB.BHZ.00 2021-09-05T18:03:45.90 10.0 positive automatic P 41 78.4335 1.84139 0.183456
II.PFO.BHZ.00 2021-09-05T18:03:44.87 10.0 positive automatic P 46 78.1966 2.0281 0.140477
IU.PET.BHZ.00 2021-09-05T18:03:43.52 10.0 positive automatic P 344 78.4674 -0.618717 0.181057
MX.SRIG.BHZ. 2021-09-05T18:03:42.34 10.0 positive automatic P 54 77.6019 3.01725 0.180948
MX.SRIG.BHZ. 2021-09-05T18:03:42.74 10.0 positive automatic pP 54 77.6019 -2.24865 0
IU.TATO.BHZ.00 2021-09-05T18:03:40.87 10.0 positive automatic P 303 77.8947 -0.106039 0.15773
AT.SMY.BHZ. 2021-09-05T18:03:25.60 10.0 positive automatic P 353 75.2684 -0.498853 0.217881
JP.JKA.BHZ. 2021-09-05T18:03:36.15 10.0 positive automatic PcP 328 74.5708 -0.289454 0
JP.YOJ.BHZ. 2021-09-05T18:03:32.60 10.0 positive automatic P 304 76.4583 -0.287842 0.183487
AT.AKUT.BHZ. 2021-09-05T18:03:31.50 10.0 positive automatic P 5 76.3587 -0.81994 0
MY.SBM.BHZ. 2021-09-05T18:03:28.77 10.0 positive automatic P 279 75.6054 0.707399 0.218503
JP.JTM.BHZ. 2021-09-05T18:03:25.40 10.0 positive automatic P 327 75.0934 0.296487 0.223875
II.ERM.BHZ.00 2021-09-05T18:03:25.62 10.0 positive automatic P 329 74.9738 1.2231 0.214905
JP.JSU.BHZ. 2021-09-05T18:03:25.05 10.0 positive automatic P 314 75.1024 -0.152074 0.218576
JP.JMN.BHZ. 2021-09-05T18:03:20.85 10.0 positive automatic P 317 74.2818 0.374969 0.232522
JP.JOW.BHZ. 2021-09-05T18:03:18.10 10.0 positive automatic P 309 73.8315 0.316889 0.23187
IU.ADK.BHZ.00 2021-09-05T18:03:16.87 10.0 positive automatic P 359 73.7743 -0.563691 0.235213
IU.MAJO.BHZ.00 2021-09-05T18:03:15.82 10.0 positive automatic P 322 73.5853 -0.550908 0.219199
G.INU.BHZ.00 2021-09-05T18:03:14.91 10.0 positive automatic P 320 73.4395 -0.551297 0.207148
JP.JGF.BHZ. 2021-09-05T18:03:14.75 10.0 positive automatic P 321 73.4226 -0.690588 0.241857
GE.JAGI.BHZ. 2021-09-05T18:02:51.82 10.0 positive automatic P 269 69.7355 -1.33603 0.265063
AU.GIRL.BHZ.00 2021-09-05T18:02:27.53 10.0 negative automatic P 254 65.3835 1.87521 0.330226
GE.LUWI.BHZ. 2021-09-05T18:02:19.87 10.0 positive automatic P 280 64.5345 -0.23884 0.333319
IU.CASY.BHZ.00 2021-09-05T18:02:18.37 10.0 positive automatic P 206 64.0874 1.18805 0.324231
AU.MORW.BHZ. 2021-09-05T18:02:05.57 10.0 positive automatic P 248 62.371 -0.280933 0.378293
GE.MMRI.BHZ. 2021-09-05T18:02:03.47 10.0 positive automatic P 272 62.1758 -1.04602 0.363658
GE.TNTI.BHZ. 2021-09-05T18:01:56.52 10.0 positive automatic P 284 61.118 -0.850093 0.386478
GE.SANI.BHZ. 2021-09-05T18:01:56.42 10.0 positive automatic P 280 61.1867 -1.4105 0.368401
IU.NWAO.BHZ.00 2021-09-05T18:01:54.42 10.0 positive automatic P 243 60.7093 -0.230366 0.383187
IU.MBWA.BHZ.00 2021-09-05T18:01:54.27 10.0 positive automatic P 257 60.8065 -1.00868 0.400062
GE.SOEI.BHZ. 2021-09-05T18:01:49.92 10.0 positive automatic P 271 59.9105 0.624634 0.412804
IU.SBA.BHZ.00 2021-09-05T18:01:30.12 10.0 positive automatic P 185 56.7032 3.40925 0.460052
AU.FITZ.BHZ. 2021-09-05T18:01:22.13 10.0 positive automatic P 262 56.165 -0.764208 0.462722
GE.FAKI.BHZ. 2021-09-05T18:01:14.07 10.0 positive automatic P 282 55.1295 -1.38578 0.484171
AU.MTN.BHZ.00 2021-09-05T18:00:54.83 10.0 positive automatic P 270 52.543 -1.7125 0.441126
AU.WRKA.BHZ.00 2021-09-05T18:00:53.38 10.0 positive automatic P 255 52.3113 -1.52291 0.510664
AU.KDU.BHZ.00 2021-09-05T18:00:45.93 10.0 positive automatic P 271 51.3477 -1.68845 0.538242
NZ.KHZ.HHZ.10 2021-09-05T18:00:45.33 10.0 positive automatic S 203 22.9044 -9.70823 0
GE.GENI.BHZ. 2021-09-05T18:00:22.47 10.0 positive automatic P 287 48.1636 -0.91185 0.546303
II.WRAB.BHZ.00 2021-09-05T18:00:17.80 10.0 positive automatic P 262 47.7215 -2.216 0.613286
IU.POHA.BHZ.00 2021-09-05T18:00:04.35 10.0 positive automatic P 25 45.5081 1.40581 0.297706
IU.WAKE.BHZ.00 2021-09-05T17:59:58.67 10.0 positive automatic P 334 45.1429 -1.03448 0.576142
AU.HTT.BHZ. 2021-09-05T17:59:37.07 10.0 positive automatic P 244 42.5907 -2.24609 0.575117
AU.MANU.BHZ.00 2021-09-05T17:59:35.05 10.0 positive automatic P 293 42.1484 -0.565043 0.715139
II.TAU.BHZ.00 2021-09-05T17:59:02.77 10.0 negative automatic P 227 38.104 0.699818 0.766255
AU.TOO.BHZ.00 2021-09-05T17:59:00.50 10.0 positive automatic P 236 37.874 -0.709806 0.770701
AU.QLP.BHZ. 2021-09-05T17:58:58.57 10.0 positive automatic P 254 37.8902 -1.70954 0.788729
AU.RABL.BHZ.00 2021-09-05T17:58:49.48 10.0 positive automatic P 294 36.9401 -2.75996 0.745537
IU.CTAO.BHZ.00 2021-09-05T17:58:48.00 10.0 positive automatic P 265 36.7179 -1.36347 0.784121
G.CAN.BHZ.00 2021-09-05T17:58:32.65 10.0 negative automatic P 239 34.6218 0.221581 0.834932
AU.ARMA.BHZ. 2021-09-05T17:58:05.80 10.0 negative automatic P 247 31.5714 -0.0685033 0.929951
IU.HNR.BHZ.00 2021-09-05T17:57:28.27 10.0 positive automatic P 293 27.6174 -2.36939 0.610687
NZ.ODZ.HHZ.10 2021-09-05T17:57:17.36 10.0 positive automatic P 204 26.2369 -0.887359 0.934579
IU.TARA.BHZ.00 2021-09-05T17:57:17.30 10.0 positive automatic P 330 26.3329 -1.77102 0.784314
AU.LHI.BHZ.00 2021-09-05T17:57:12.98 10.0 positive automatic P 242 25.5455 1.02873 0.930233
G.PPTF.BHZ.00 2021-09-05T17:56:56.75 10.0 negative automatic P 84 23.6987 1.51872 0.909091
IU.SNZO.BHZ.00 2021-09-05T17:56:33.12 10.0 positive automatic P 203 21.514 0.893939 0.952381
ND.KOUNC.BHZ.00 2021-09-05T17:56:15.60 10.0 positive automatic P 270 19.9345 0.475869 0.888889
G.SANVU.BHZ.00 2021-09-05T17:56:01.15 10.0 positive automatic P 287 18.5909 0.741109 0.930233
ND.ONTNC.BHZ.00 2021-09-05T17:55:51.85 10.0 positive automatic P 265 17.771 1.18134 0.909091
AU.NFK.BHZ.00 2021-09-05T17:55:47.12 10.0 positive automatic P 242 17.4924 -0.115417 0.625
NZ.OUZ.HHZ.10 2021-09-05T17:55:39.78 10.0 positive automatic P 216 17.006 -1.35756 0.328407
IU.FUNA.BHZ.00 2021-09-05T17:55:12.65 10.0 positive automatic P 334 14.7113 1.25955 0.747664
IU.RAR.BHZ.00 2021-09-05T17:54:51.00 10.0 positive automatic P 90 13.5779 -3.93171 0.963855
II.MSVF.BHZ.00 2021-09-05T17:53:48.57 10.0 positive automatic P 299 8.2407 5.56057 0.869565
IU.AFI.BHZ.00 2021-09-05T17:53:43.17 10.0 positive automatic P 18 8.3276 -1.01667 0.869565
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