Magnitude 2.2, Thu Feb 1 2024 4:09 AM


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Origin


PublicID 2024p082787
UTC Time 2024-01-31T15:09:03Z
Latitude -36.97 (± 34.8 km)
Longitude 178.39 (± 43.0 km)
Depth 133 km (± 90 km)
Depth Type free
Earth Model iasp91
Used Phase Count 7
Used Station Count 7
Standard Error 0.40 (s)
Azimuthal Gap 320.91 (degrees)
Minimum Distance 0.85 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (MLv) 2.2 (± 0.8)  
MLv 2.2 (± 0.8) 3
M 2.2 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


-17.0-15.0-13.0-11.0-9.0-7.0-5.0-3.0-1.01.03.05.07.09.011.013.015.017.0residual (s)0123Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.04.0Magnitude123Distance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (MLv)


-1.00.01.0Residual123Distance (degrees)Magnitude Residuals (MLv)