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Origin
PublicID |
3550173 |
UTC Time |
2011-07-21T17:39:32Z |
Latitude |
-43.63 (± 0.0
km)
|
Longitude |
172.21 (± 0.0
km)
|
Depth |
12 km (± 1 km) |
Depth Type |
free |
Earth Model |
nz1dr |
Used Phase Count |
56 |
Used Station Count |
53 |
Standard Error |
0.19 (s) |
Azimuthal Gap |
48.00 (degrees) |
Minimum Distance |
0.04 (degrees) |
Magnitudes
Type |
Magnitude |
Station Count |
Preferred (Mw) |
4.7 |
|
ML |
5.2 (± 0.3) |
84 |
Mw |
4.7 |
0 |
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).