National Advisory: Tsunami activity. We expect New Zealand coastal areas to experience strong and unusual currents and unpredictable surges at the shore following a M6.8 earthquake off the West Coast of the South Island at 2025-03-25 2:43 PM. Please see NEMA (The National Emergency Management Agency) for official tsunami warning information.
This quake was widely felt in both islands. Strong shaking was reported as far as Palmerston North and Masterton.
| PublicID | 2014p051675 |
| UTC Time | 2014-01-20T02:52:45Z |
| Latitude | -40.62 (± 0.7 km) |
| Longitude | 175.86 (± 1.2 km) |
| Depth | 34 km (± 2 km) |
| Depth Type | free |
| Earth Model | nz3drx |
| Used Phase Count | 29 |
| Used Station Count | 20 |
| Standard Error | 0.30 (s) |
| Azimuthal Gap | 84.47 (degrees) |
| Minimum Distance | 0.10 (degrees) |
| Type | Magnitude | Station Count |
| Preferred (MLv) | 6.2 (± 0.3) | |
| MLv | 6.2 (± 0.3) | 124 |
| ML | 6.5 (± 0.3) | 12 |
| MLv | 6.0 (± 0.2) | 7 |
| M | 6.1 | 124 |
| ML | 6.0 | 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).
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.