Magnitude 3.5, Tue Aug 25 2015 11:27 AM


Download Event Information


Origin


PublicID 2015p637777
UTC Time 2015-08-24T23:27:43Z
Latitude -44.53 (± 3.1 km)
Longitude 168.84 (± 3.4 km)
Depth 5 km (± 8 km)
Depth Type free
Earth Model iasp91
Used Phase Count 11
Used Station Count 6
Standard Error 0.47 (s)
Azimuthal Gap 97.24 (degrees)
Minimum Distance 0.32 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 3.5  
MLv 3.5 (± 0.2) 6
ML 3.7 (± 0.3) 6
M 3.5 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


-10.0-8.0-6.0-4.0-2.00.02.04.06.08.010.0residual (s)0123456789Distance (degrees)Pick Residuals

Station Magnitudes (MLv)


0.01.02.03.04.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Station Magnitudes (ML)


0.01.02.03.04.05.0MagnitudeDistance (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)