Magnitude 3.8, Sun Apr 27 2025 12:37 PM


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Origin


PublicID 2025p313586
UTC Time 2025-04-27T00:37:14Z
Latitude -31.54 (± 39.9 km)
Longitude -178.15 (± 28.7 km)
Depth 490 km (± 126 km)
Depth Type free
Earth Model iasp91
Used Phase Count 12
Used Station Count 9
Standard Error 1.21 (s)
Azimuthal Gap 330.44 (degrees)
Minimum Distance 6.87 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (Mw(mB)) 3.8 (± 0.4)  
MLv 5.0 (± 0.1) 5
mB 4.6 (± 0.1) 12
Mw(mB) 3.8 (± 0.4) 12
M 4.2 12

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


-19.0-17.0-15.0-13.0-11.0-9.0-7.0-5.0-3.0-1.01.03.05.07.09.011.013.015.017.019.0residual (s)0246810121416Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.04.05.06.0Magnitude7Distance (degrees)Station Magnitudes (MLv)

Station Magnitudes (mB)


0.01.02.03.04.05.06.0Magnitude791113Distance (degrees)Station Magnitudes (mB)

Magnitude Residuals (MLv)


-1.00.01.0Residual7Distance (degrees)Magnitude Residuals (MLv)

Magnitude Residuals (mB)


-1.00.01.0Residual791113Distance (degrees)Magnitude Residuals (mB)