The first a - 5.9 magnitude quake - struck 35 kilometres west of the Milford Sound at a depth of five kilometres at 10.20am.
Five minutes later, another 4.2 magnitude quake struck 25 kilometres from the Sound - at a depth of eight kilometres - followed by a third 8 minutes later, with a magnitude of 3.4 at a depth of 5 km.
Geonet describes the first quake as moderate ... although some reports have described it as extreme and severe.