* NEW ZEALAND CIVIL DEFENSE HAS ISSUED A TSUNAMI THREAT
MESSAGE FOR THE EAST COAST OF SOUTH ISLAND.
* TSUNAMI THREAT BEYOND NEW ZEALAND IS NOT EXPECTED.
* THE FOLLOWING ARE TSUNAMI WAVE OBSERVATIONS FROM COASTAL
AND/OR DEEP-OCEAN SEA LEVEL GAUGES AT THE INDICATED
LOCATIONS. THE MAXIMUM TSUNAMI HEIGHT IS MEASURED WITH
RESPECT TO THE NORMAL TIDE LEVEL.
GAUGE TIME OF MAXIMUM WAVE
COORDINATES MEASURE TSUNAMI PERIOD
GAUGE LOCATION LAT LON (UTC) HEIGHT (MIN)
CASTLEPOINT NZ 40.9S 176.2E 1210 0.12M/ 0.4FT 18
WELLINGTON NZ 41.3S 174.8E 1232 0.43M/ 1.4FT 16
KAIKOURA NZ 42.4S 173.7E 1140 1.47M/ 4.8FT 16
NZ Geonet reports Mag 7.5 at 15 km depth, 15 km north-east of Culverden, which is about 53 km NNE of AmberleyHere's the USGS info:
They are also reporting 7.8.
As to why there are varying figures on the scale (USGS changed from 7.4 to now 7.9, Potsdam had 7. 8 and I've heard 6.6 by local reports):
A geology professor on a news channel here said: "It's difficult to determine the exact magnitude because it lasted so long, more than 2 minutes." Aftershocks are still occurring, but the danger of a major tsunami is likely banned.
And interestingly, almost all of the larger following events were not even in the area of the main shock.
So far 2 people have been reported killed, one when their house collapsed on them
Two people have been pulled alive from a home destroyed in the quake.
One person is understood to have died at the Elms homestead near Kaikoura Airport.
The two buildings on the property are piles of rubble, barely recognisable as buildings.
GeoNet says the massive 7.5 earthquake overnight seemed so long was because it was two quakes, not one - lasting a combined two minutes and triggering a swarm of frightening aftershocks.
This is interesting:
EDIT: also, I think the largest aftershock so far has been 6.2 in the Nelson region. That hit at 1.34pm.
Nelson to Kaikoura is about 130 km (80.7 miles). Is it possible Nelson received some P-waves? Possibly from the Mag 6+ group that were 12 to 23 km N to NNW from Kaikoura toward Blenheim?
A number of years ago, I was about 60 miles from a Mag 6.5, and I felt the P-wave then S-wave. I was sitting on a large couch, and all of a sudden, it started shaking like an imbalanced washing machine. Moments latter, it started bouncing.
Did you feel the two just before?
then 42 seconds later, at a different location,
When I woke up because of the quake (I'm in Lower Hutt), I thought it would stop. But it got more intense and once I heard things falling down in other rooms, I thought 'this isn't good'. I expected that the quake was located quite near Wellington. It did go through my mind that the house could collapse, once I heard things falling. I -cannot- imagine what it was like down in Christchurch 2010 and 2011.I woke just after midnight to my house falling apart again. There was slow rolling with no high frequency component which lasted for 2mins. It was different from the violent jolting of our Christchurch quakes of 5 years ago and I realized the quake was not local and some poor blighters were really in trouble. My first thought was that it was the Alpine fault as we expect this kind of quake from that fault. Luckily it was at night or casualties could have been a lot higher.
Police have cordoned off an area of central Wellington over fears a large building is structurally unsafe.
Emergency Services rushed to Molesworth St, near Parliament, where the road has been blocked off.
My first thought was that it was the Alpine fault as we expect this kind of quake from that fault.