Download Event Information
Origin
PublicID |
2017p615815 |
UTC Time |
2017-08-16T20:26:22Z |
Latitude |
-40.87 (± 2.0
km)
|
Longitude |
172.51 (± 3.1
km)
|
Depth |
4 km (± 2 km) |
Depth Type |
free |
Earth Model |
iasp91 |
Used Phase Count |
36 |
Used Station Count |
27 |
Standard Error |
0.58 (s) |
Azimuthal Gap |
156.55 (degrees) |
Minimum Distance |
0.05 (degrees) |
Magnitudes
Type |
Magnitude |
Station Count |
Preferred (M) |
4.5 |
|
MLv |
4.5 (± 0.2) |
85 |
ML |
4.6 (± 0.2) |
18 |
M |
4.5 |
85 |
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).