Magnitude 1.6, Tue Oct 31 2023 7:26 PM


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Origin


PublicID 2023p819643
UTC Time 2023-10-31T06:26:19Z
Latitude -38.63 (± 54.7 km)
Longitude 176.09 (± 70.9 km)
Depth 5 km (± 57 km)
Depth Type free
Earth Model nz3drx
Used Phase Count 9
Used Station Count 9
Standard Error 0.27 (s)
Azimuthal Gap 110.42 (degrees)
Minimum Distance 0.02 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 1.6  
ML 1.6 (± 0.5) 5
M 1.6 5
MLv 1.6 (± 0.5) 5

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


-28.0-26.0-24.0-22.0-20.0-18.0-16.0-14.0-12.0-10.0-8.0-6.0-4.0-2.00.02.04.06.08.010.012.014.016.018.020.022.024.026.028.0residual (s)01Distance (degrees)Pick Residuals

Station Magnitudes (ML)


0.01.02.03.0MagnitudeDistance (degrees)Station Magnitudes (ML)

Station Magnitudes (MLv)


0.01.02.03.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (ML)


-2.0-1.00.01.02.0ResidualDistance (degrees)Magnitude Residuals (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)