Magnitude 4.5, Sun Dec 31 2023 10:12 PM


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Origin


PublicID 2023p984830
UTC Time 2023-12-31T09:12:48Z
Latitude -28.20 (± 7.5 km)
Longitude -175.37 (± 10.2 km)
Depth 33 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 10
Used Station Count 7
Standard Error 1.28 (s)
Azimuthal Gap 154.95 (degrees)
Minimum Distance 2.48 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (mB) 4.5  
mB 4.5 1
ML 5.5 1
MLv 5.5 1
Mw(mB) 3.7 (± 0.4) 2
M 5.5 1

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


-9.0-7.0-5.0-3.0-1.01.03.05.07.09.0residual (s)02468101214161820222426283032343638404244464850Distance (degrees)Pick Residuals

Station Magnitudes (mB)


0.01.02.03.04.05.0MagnitudeDistance (degrees)Station Magnitudes (mB)

Station Magnitudes (ML)


0.01.02.03.04.05.06.0MagnitudeDistance (degrees)Station Magnitudes (ML)

Station Magnitudes (MLv)


0.01.02.03.04.05.06.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (mB)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (mB)

Magnitude Residuals (ML)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)