Magnitude 3.7, Wed Sep 6 2023 10:52 AM


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Origin


PublicID 2023p670146
UTC Time 2023-09-05T22:52:56Z
Latitude -32.11 (± 35.2 km)
Longitude -179.24 (± 90.1 km)
Depth 100 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 10
Used Station Count 6
Standard Error 0.77 (s)
Azimuthal Gap 177.26 (degrees)
Minimum Distance 3.06 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (Mw(mB)) 3.7 (± 0.4)  
M 4.3 4
MLv 4.4 (± 0.3) 2
Mw(mB) 3.7 (± 0.4) 4
mB 4.5 (± 0.2) 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


-4.0-3.0-2.0-1.00.01.02.03.04.0residual (s)012345678Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.04.05.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Station Magnitudes (mB)


0.01.02.03.04.05.0Magnitude7Distance (degrees)Station Magnitudes (mB)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)

Magnitude Residuals (mB)


-1.00.01.0Residual7Distance (degrees)Magnitude Residuals (mB)