Magnitude 2.1, Sun Dec 21 2025 4:37 PM


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Origin


PublicID 2025p957165
UTC Time 2025-12-21T03:37:50Z
Latitude -37.45 (± 68.2 km)
Longitude 176.28 (± 120.0 km)
Depth 176 km (± 127 km)
Depth Type free
Earth Model nz3drx
Used Phase Count 9
Used Station Count 9
Standard Error 2.32 (s)
Azimuthal Gap 148.10 (degrees)
Minimum Distance 1.11 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 2.1  
MLv 2.1 (± 0.5) 2
M 2.1 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


-5.0-3.0-1.01.03.05.0residual (s)012Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)