Magnitude 2.9, Sat May 27 2023 11:12 PM

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PublicID 2023p395858
UTC Time 2023-05-27T11:12:58Z
Latitude -36.00 (± 17.5 km)
Longitude 179.36 (± 27.2 km)
Depth 100 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 12
Used Station Count 9
Standard Error 0.34 (s)
Azimuthal Gap 342.14 (degrees)
Minimum Distance 2.16 (degrees)


Type Magnitude Station Count
Preferred (MLv) 2.9 (± 0.4)  
MLv 2.9 (± 0.4) 4
ML 2.7 (± 0.2) 4
M 2.9 4

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

- (s)0123Distance (degrees)Pick Residuals

Station Magnitudes (MLv) (degrees)Station Magnitudes (MLv)

Station Magnitudes (ML) (degrees)Station Magnitudes (ML)

Magnitude Residuals (MLv)

- (degrees)Magnitude Residuals (MLv)

Magnitude Residuals (ML)

- (degrees)Magnitude Residuals (ML)