Magnitude 2.7, Sat Apr 10 2021 4:48 PM


Download Event Information


Origin


PublicID 2021p268109
UTC Time 2021-04-10T04:48:59Z
Latitude -37.17 (± 31.5 km)
Longitude -179.76 (± 15.2 km)
Depth 33 km (± 0 km)
Depth Type operator assigned
Earth Model iasp91
Used Phase Count 8
Used Station Count 6
Standard Error 0.34 (s)
Azimuthal Gap 337.58 (degrees)
Minimum Distance 1.59 (degrees)

Magnitudes


Type Magnitude Station Count
Preferred (M) 2.7  
ML 2.7 (± 0.2) 5
MLv 2.7 (± 0.1) 2
M 2.7 2

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)012Distance (degrees)Pick Residuals

Station Magnitudes (ML)


0.01.02.03.0Magnitude2Distance (degrees)Station Magnitudes (ML)

Station Magnitudes (MLv)


0.01.02.03.0MagnitudeDistance (degrees)Station Magnitudes (MLv)

Magnitude Residuals (ML)


-1.00.01.0Residual2Distance (degrees)Magnitude Residuals (ML)

Magnitude Residuals (MLv)


-1.00.01.0ResidualDistance (degrees)Magnitude Residuals (MLv)