Magnitude 3.5, Tue May 16 2023 3:59 AM


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Origin


PublicID 2023p363965
UTC Time 2023-05-15T15:59:45Z
Latitude -32.36 (± 53.1 km)
Longitude 179.82 (± 62.1 km)
Depth 241 km (± 153 km)
Depth Type free
Earth Model iasp91
Used Phase Count 10
Used Station Count 7
Standard Error 0.60 (s)
Azimuthal Gap 352.36 (degrees)
Minimum Distance 5.34 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (Mw(mB)) 3.5 (± 0.4)  
MLv 4.3 (± 0.2) 5
mB 4.4 (± 0.2) 5
Mw(mB) 3.5 (± 0.4) 2

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


-6.0-4.0-2.00.02.04.06.0residual (s)0246810Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.04.05.0Magnitude6Distance (degrees)Station Magnitudes (MLv)

Station Magnitudes (mB)


0.01.02.03.04.05.0Magnitude6789Distance (degrees)Station Magnitudes (mB)

Magnitude Residuals (MLv)


-1.00.01.0Residual6Distance (degrees)Magnitude Residuals (MLv)

Magnitude Residuals (mB)


-1.00.01.0Residual6789Distance (degrees)Magnitude Residuals (mB)