Magnitude 2.3, Fri Oct 30 2020 7:50 AM


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Origin


PublicID 2020p818338
UTC Time 2020-10-29T18:50:44Z
Latitude -42.08 (± 48.9 km)
Longitude 172.25 (± 33.0 km)
Depth 111 km (± 75 km)
Depth Type free
Earth Model iasp91
Used Phase Count 5
Used Station Count 5
Standard Error 0.45 (s)
Azimuthal Gap 307.35 (degrees)
Minimum Distance 0.70 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 2.3  
ML 2.2 (± 0.3) 4
MLv 2.3 1
M 2.3 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


-37.0-35.0-33.0-31.0-29.0-27.0-25.0-23.0-21.0-19.0-17.0-15.0-13.0-11.0-9.0-7.0-5.0-3.0-1.01.03.05.07.09.011.013.015.017.019.021.023.025.027.029.031.033.035.037.0residual (s)0123Distance (degrees)Pick Residuals

Station Magnitudes (ML)


0.01.02.03.0Magnitude1Distance (degrees)Station Magnitudes (ML)

Station Magnitudes (MLv)


0.01.02.03.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (ML)


-1.00.01.0Residual1Distance (degrees)Magnitude Residuals (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)