Details of earthquake:
Magnitude 7.9 occurred near the New Zealand south coast at 7:22pm EST.
Australia's warning response:
|7.22pm||Earthquake detected off the south-west tip of New Zealand.|
|7.30pm||Geoscience Australia locates the earthquake and activates the tsunami warning centre.|
|7.46pm||The bureau issues a Tsunami Watch 24 minutes after the earthquake.|
|7.50pm||Deep-ocean buoy in the southern Tasman Sea confirms the existence of a tsunami.|
|8.05pm||Tsunami Warning (Land Threat) issued for Lord Howe Island.|
|8.17pm||Tsunami Warning (Marine Threat) issued for the mainland, Tasmania and Norfolk Island.|
|10.30pm||Tsunami waves of about 30cm are recorded at Port Kembla.|
Impacts on Australia
Small tsunami were observed (approximately 3 hours after the earthquake) at several Australian sea-level gauges, including Port Kembla, NSW, and no damage was reported. The largest tsunami was at Southport in southern Tasmania which recorded a 55-centimetre sea level difference above the expected tidal level.
Figure 1: Sea level at Port Kembla, NSW, during the tsunami on 15 July 2009.