Magnitude 3.3, Wed Nov 22 2023 7:43 AM


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Origin


PublicID 2023p877787
UTC Time 2023-11-21T18:43:46Z
Latitude -31.16 (± 59.4 km)
Longitude 179.46 (± 157.3 km)
Depth 375 km (± 141 km)
Depth Type free
Earth Model iasp91
Used Phase Count 9
Used Station Count 7
Standard Error 0.66 (s)
Azimuthal Gap 353.19 (degrees)
Minimum Distance 6.72 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (Mw(mB)) 3.3 (± 0.4)  
mB 4.2 (± 0.4) 3
Mw(mB) 3.3 (± 0.4) 3
MLv 4.1 1
M 4.0 3

GeoNet combines magnitudes into a summary magnitude, M, which consists of a weighted average of the individual magnitudes and attempts to be a best possible compromise between all magnitudes for a range of earthquake sizes. Summary magnitude for GeoNet is then defined as:

M = (2 * MLv + (0.4 * number_of stations(Mw(mB)) - 1) * Mw(mB)) / (2 + (0.4 * number_of_stations(Mw(mB)) - 1))

Where MLv is local magnitude calculated on the vertical component and Mw(mB) is a Mw estimation based of mB by Bormann and Saul (2008).

Origin Map


Map of New Zealand.

Map showing stations with picks used to locate the earthquake. Stations with picks that have a zero weight in the solution are shown as small grey circles. Those with a higher weight are shown as larger circles. The quake is shown by the largest circle.

Pick Residuals


-3.0-2.0-1.00.01.02.03.0residual (s)012345678Distance (degrees)Pick Residuals

Station Magnitudes (mB)


0.01.02.03.04.05.0Magnitude7Distance (degrees)Station Magnitudes (mB)

Station Magnitudes (MLv)


0.01.02.03.04.05.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (mB)


-1.00.01.0Residual7Distance (degrees)Magnitude Residuals (mB)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)