Magnitude 4.3, Mon Aug 4 2025 1:09 PM


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Origin


PublicID 2025p581216
UTC Time 2025-08-04T01:09:10Z
Latitude -24.19 (± 23.2 km)
Longitude -178.37 (± 41.2 km)
Depth 600 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 9
Used Station Count 8
Standard Error 0.55 (s)
Azimuthal Gap 328.92 (degrees)
Minimum Distance 5.06 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (mB) 4.3 (± 0.2)  
mB 4.3 (± 0.2) 16
Mw(mB) 3.4 (± 0.4) 16
M 3.4 16

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)0246810121416182022Distance (degrees)Pick Residuals

Station Magnitudes (mB)


0.01.02.03.04.05.06.0Magnitude151719Distance (degrees)Station Magnitudes (mB)

Magnitude Residuals (mB)


-1.00.01.0Residual151719Distance (degrees)Magnitude Residuals (mB)