Magnitude 0.3, Wed Mar 17 2021 9:00 PM


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Origin


PublicID 2021p203602
UTC Time 2021-03-17T08:00:06Z
Latitude -39.54 (± 7.2 km)
Longitude 175.69 (± 5.7 km)
Depth 5 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 15
Used Station Count 9
Standard Error 0.31 (s)
Azimuthal Gap 260.52 (degrees)
Minimum Distance 0.15 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 0.3  
M 0.3 2

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


-1.00.01.0residual (s)0Distance (degrees)Pick Residuals