Magnitude 0.6, Wed Sep 18 2019 7:40 AM


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Origin


PublicID 2019p702215
UTC Time 2019-09-17T19:40:27Z
Latitude -39.47 (± 8.3 km)
Longitude 175.66 (± 4.7 km)
Depth 14 km (± 12 km)
Depth Type free
Earth Model iasp91
Used Phase Count 11
Used Station Count 8
Standard Error 0.14 (s)
Azimuthal Gap 252.28 (degrees)
Minimum Distance 0.10 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 0.6  
ML 0.9 (± 0.5) 5
MLv 0.6 (± 0.3) 6
M 0.6 6

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

Station Magnitudes (ML)


0.01.02.0MagnitudeDistance (degrees)Station Magnitudes (ML)

Station Magnitudes (MLv)


0.01.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (ML)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)