Magnitude 1.3, Sun Sep 23 2018 12:23 PM


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Origin


PublicID 2018p716260
UTC Time 2018-09-23T00:23:37Z
Latitude -39.29 (± 2.5 km)
Longitude 175.52 (± 7.5 km)
Depth 13 km (± 4 km)
Depth Type free
Earth Model nz3drx
Used Phase Count 10
Used Station Count 5
Standard Error 0.28 (s)
Azimuthal Gap 185.55 (degrees)
Minimum Distance 0.06 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 1.3  
MLv 1.3 1
ML 1.0 (± 0.4) 5
M 1.3 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


-9.0-7.0-5.0-3.0-1.01.03.05.07.09.0residual (s)01Distance (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)