Istituto Nazionale di Geofisica e Vulcanologia

Earthquake with magnitude of Mwp 6.1 on date 23-10-2015 and time 04:04:17 (UTC) in region South Africa [Sea]

A magnitude Mwp 6.1 earthquake occured in region: South Africa [Sea], on

  • 23-10-2015 04:04:17 (UTC)
  • 23-10-2015 06:04:17 (UTC +02:00) Italian time

and geographic coordinates (lat, lon) -45.6820, 37.1780 at 1 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.

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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
Felt maps
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100 		mb 5.4
Mwp 6.1
Mwpd 6.1 		2015-10-23
04:04:17		 -45.682 37.1777 1 2015-10-23
04:21:21		 Sala Sismica INGV-Roma 21916961
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2015-10-23 04:04:17
Latitude -45.6820
Longitude 37.1777
Depth (km) 1 (from location)
Evaluation mode of Origin automatic
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV-A
Event type earthquake
Origin ID 21916961

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 17397
Semi-minor axis of confidence ellipse (meter) 1596
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 60
Circular confidence region, given by single value of horizontal uncertainty (meter) 14085.1
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 50.9178
Number of associated phases, regardless of their use for origin computation 37
Number of defining phases 37
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 1.22622
Epicentral distance of station closest to the epicenter (degree) 10.19775
Epicentral distance of station farthest from the epicenter (degree) 88.64289
Number of stations at which the event was observed 36
Number of stations from which data was used for origin computation 36
Magnitudes information

Mwpd:6.1

Field Value
Value 6.1
Uncertainty 0.3
Num. used stations 7
Type of magnitude Mwpd
Reference to an origin 21916961
Agency INGV
Autore early-est_ee1.1.8
Time of creation (UTC) 2015-10-23 04:21:23

Mwp:6.1

Field Value
Value 6.1
Uncertainty 0.3
Num. used stations 9
Type of magnitude Mwp
Reference to an origin 21916961
Agency INGV
Autore early-est_ee1.1.8
Time of creation (UTC) 2015-10-23 04:21:23

mb:5.4

Field Value
Value 5.4
Uncertainty 0.2
Num. used stations 33
Type of magnitude mb
Reference to an origin 21916961
Agency INGV
Autore early-est_ee1.1.8
Time of creation (UTC) 2015-10-23 04:21:23
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance(km) Takeoff_angle Residual Weight
GT.LPAZ.BHZ.00 2015-10-23T04:17:11.48 10.0 positive automatic P 248 9839.3619 -0.386781 0.0967208
GE.LVC.BHZ.00 2015-10-23T04:16:51.52 10.0 positive automatic P 243 9375.2931 0.448545 0.0663337
AU.KDU.BHZ. 2015-10-23T04:16:50.65 10.0 positive automatic P 103 9389.3679 -0.569538 0.139777
GE.KARP.BHZ. 2015-10-23T04:16:36.90 10.0 negative automatic P 352 9071.7636 0.384992 0.151999
IU.LCO.BHZ.00 2015-10-23T04:16:31.82 10.0 positive automatic P 237 8971.3641 -0.187754 0.171473
II.WRAB.BHZ.00 2015-10-23T04:16:30.57 10.0 negative automatic P 109 8955.9573 -0.363543 0.144565
AU.FITZ.BHZ. 2015-10-23T04:16:06.51 10.0 negative automatic P 102 8447.322 0.957144 0.21582
GE.EIL.BHZ. 2015-10-23T04:16:01.60 10.0 positive automatic P 358 8366.7138 0.179579 0.215663
AU.TOO.BHZ. 2015-10-23T04:15:59.75 10.0 positive automatic P 129 8301.8898 1.62391 0.219136
GT.CPUP.BHZ.00 2015-10-23T04:15:56.25 10.0 negative automatic P 248 8263.2618 0.237774 0.215296
AU.HTT.BHZ. 2015-10-23T04:15:54.12 10.0 positive automatic P 122 8214.5439 0.563954 0.205976
IU.RCBR.BHZ.00 2015-10-23T04:15:54.62 10.0 positive automatic P 278 8218.2957 0.920825 0.235035
AU.WRKA.BHZ. 2015-10-23T04:15:48.80 10.0 positive automatic P 109 8115.4764 0.509098 0.248114
II.UOSS.BHZ.00 2015-10-23T04:15:43.52 10.0 positive automatic P 18 8071.1541 -2.34172 0.243786
GT.PLCA.BHZ.00 2015-10-23T04:15:42.75 10.0 positive automatic P 229 8014.0668 -0.178829 0.23315
IU.KOWA.BHZ.00 2015-10-23T04:15:33.35 10.0 negative automatic P 318 7851.5295 -0.617035 0.248464
IU.MBWA.BHZ.00 2015-10-23T04:15:30.27 10.0 positive automatic P 100 7765.0938 1.10026 0.262514
IU.TRQA.BHZ.00 2015-10-23T04:15:25.32 10.0 negative automatic P 236 7691.7228 0.171872 0.289138
II.PALK.BHZ.00 2015-10-23T04:15:04.72 10.0 negative automatic P 49 7289.5476 2.50706 0.31904
C.GO10.BHZ. 2015-10-23T04:14:52.68 10.0 positive automatic P 219 7081.3893 2.66932 0.32765
GT.DBIC.BHZ.00 2015-10-23T04:14:51.95 10.0 negative automatic P 312 7146.624 -1.83361 0.335088
AU.MORW.BHZ. 2015-10-23T04:14:41.05 10.0 positive automatic P 104 6909.8166 1.37632 0.346781
GE.SOCY.BHZ. 2015-10-23T04:14:23.62 10.0 negative automatic P 19 6640.0422 0.373228 0.404328
G.ATD.BHZ.00 2015-10-23T04:14:06.30 10.0 negative automatic P 7 6375.6291 -0.315067 0.207161
IU.PMSA.BHZ.00 2015-10-23T04:13:41.72 10.0 positive automatic P 211 5982.012 0.681247 0.240263
GT.VNDA.BHZ.00 2015-10-23T04:13:28.63 10.0 negative automatic P 167 5796.0204 -0.0724842 0.506175
II.HOPE.BHZ.00 2015-10-23T04:12:40.62 10.0 positive automatic P 231 5097.3642 0.189285 0.622627
II.MBAR.BHZ.00 2015-10-23T04:12:36.87 10.0 negative automatic P 351 5043.1407 0.072691 0.61681
IU.CASY.BHZ.00 2015-10-23T04:12:14.32 10.0 negative automatic P 145 4733.817 0.135507 0.609979
GE.SNAA.BHZ. 2015-10-23T04:10:44.21 10.0 positive automatic P 202 3559.1262 -0.42199 0.908157
IU.TSUM.BHZ.00 2015-10-23T04:10:34.47 10.0 positive automatic P 322 3444.3189 -1.13283 0.908643
AU.MAW.BHZ. 2015-10-23T04:09:47.31 10.0 negative automatic P 158 2848.2045 -0.122277 0.869565
GE.VOI.BHZ. 2015-10-23T04:09:42.20 10.0 positive automatic P 21 2763.9 1.49768 0.909091
GT.BOSA.BHZ.00 2015-10-23T04:08:44.40 10.0 negative automatic P 327 2162.7573 -0.30983 0.930233
G.CRZF.BHZ.00 2015-10-23T04:08:31.75 10.0 positive automatic S 99 1131.9558 -5.71449 0
II.SUR.BHZ.00 2015-10-23T04:08:31.57 10.0 positive automatic P 311 2034.5079 -0.381023 0.952381
G.CRZF.BHZ.00 2015-10-23T04:06:41.65 10.0 positive automatic P 99 1131.9558 -2.0208 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