Magnitude 4.2, Sun Jan 7 2024 4:50 AM


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Origin


PublicID 2024p015302
UTC Time 2024-01-06T15:50:59Z
Latitude -27.80 (± 21.3 km)
Longitude -176.25 (± 35.1 km)
Depth 327 km (± 17 km)
Depth Type free
Earth Model iasp91
Used Phase Count 11
Used Station Count 9
Standard Error 0.74 (s)
Azimuthal Gap 170.27 (degrees)
Minimum Distance 2.07 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (mB) 4.2 (± 0.2)  
mB 4.2 (± 0.2) 7
Mw(mB) 3.3 (± 0.4) 3
MLv 4.0 1
M 3.9 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


-2.0-1.00.01.02.0residual (s)0246810121416Distance (degrees)Pick Residuals

Station Magnitudes (mB)


0.01.02.03.04.05.0Magnitude1315Distance (degrees)Station Magnitudes (mB)

Station Magnitudes (MLv)


0.01.02.03.04.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (mB)


-1.00.01.0Residual1315Distance (degrees)Magnitude Residuals (mB)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)