Magnitude 0.7, Fri Dec 8 2017 1:52 AM


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Origin


PublicID 2017p920366
UTC Time 2017-12-07T12:52:38Z
Latitude -39.15 (± 3.7 km)
Longitude 175.36 (± 7.1 km)
Depth 7 km (± 10 km)
Depth Type free
Earth Model iasp91
Used Phase Count 10
Used Station Count 5
Standard Error 0.17 (s)
Azimuthal Gap 209.64 (degrees)
Minimum Distance 0.10 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 0.7  
MLv 0.7 (± 0.2) 5
ML 1.1 (± 0.2) 5
M 0.7 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


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

Station Magnitudes (MLv)


0.01.02.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Station Magnitudes (ML)


0.01.02.0MagnitudeDistance (degrees)Station Magnitudes (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)

Magnitude Residuals (ML)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (ML)