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cooper · 20-12-2007, 03:31

just heard that you NZ guys had a big earthquake....? Alan , Foxy, ? all you other friends all cool ?...

MarkJ · 20-12-2007, 03:40

AFP - 1 hour ago
WELLINGTON (AFP) — A powerful earthquake measuring 6.8 struck New Zealand's North Island late Thursday, causing considerable damage in the city of Gisborne

Reference Number2839343/GUniversal TimeDecember 20 2007 at 7:55NZ Daylight TimeThursday, December 20 2007 at 8:55 pmLatitude, Longitude38.86°S, 178.52°EFocal Depth40 kmRichter magnitude6.8RegionHikurangi TroughLocation

50 km south-east of Gisborne
400 km south-east of Auckland

**GordMay** · 20-12-2007, 03:49

Hope all's well!

Magnitude 6.8, Thursday, December 20 2007 at 8:55 pm NZDT , 50 km south-east of Gisborne at 38.86̊S x 178.52̊E.
Reports from Gisborne vary between “considerable” to “moderate” damage; but no injuries have (yet) been reported.
The quake was felt all the way down to Christchurch.

Latest Earthquakes Magnitude 2.5 or Greater in the United States and Adjacent Areas and Magnitude 4.0 or Greater in the Rest of the World - Last 7 days
Latest Earthquakes in the World - Past 7 days

Earthquakes with a Richter magnitude of 6.1 to 6.9 can be destructive in areas up to about 100 kilometers across where people live, often causing much damage to buildings: chimneys fall, houses move on foundations.

The Richter is a logarithmic scale, meaning that the numbers on the scale measure factors of 10. So, for example, an earthquake that measures 4.0 on the Richter scale is 10 times larger than one that measures 3.0. The maximum quake rating ever measured (Indonesia's Sumatra quake/tsunami, December 26, 2004) was about 8.9.

Whimsical · 20-12-2007, 04:12

Did Wheels have another oops day and kiss the pier

Mike

**Alan Wheeler** · 20-12-2007, 10:48

Shhhh! Don't tell everyone. With a bit of luck, I may have got away with it :-)
I felt the rocking. But we get those so often, you get used to it. What I have learn't is that you can tell by the motion if the quake was large but far away, (which this one was), or small but closer. I sit right on top of the biggest fault line we have. Seafox and Marauder do too. We are all waiting for the long over due "bigone". When this fault line lets go, it is usually in the high 7's from viewing past records. The last one was 7.8 and the Wellington Airport now stands on what was once sea before that quake.
Anyway, back to the quake of last night. A few buildings were damaged and the Central Business District (CBD) is closed today. No one was hurt. The quake centre was 50Km off shore. Interestingly, the epicentre sits very close to an area that has been highlighted as a possible Tsunami causing geographical feature. A large area of silt and sand sitting on the top edge of a huge drop. Scientists are worried the soft silt may go over the edge, creating an enormus water movement what would result in a huge Tidal wave. We don't get Tidal waves often here. Nothing big in known Human times, but there is evedence of Waves being created by these features that are scattered around the country, that have created walls of water well over 150ft high.

Seismicity Map

**Alan Wheeler** · 20-12-2007, 10:54

If you take note of the pictures above. You will see on the first one, the years and magitude of past quakes for just this region alone. On the picture below that, you wil not lots of dots in colours from Orange to Blue. The colour represents the depth of the quake. Not that the orange is on one side(east) and the blue on the other(West). That is the affect of one plate diving below the other. So the Westerly "Tasman" plate is going under the the Easterly Pacific Plate. The region in the middle is the mountanous backbone of NZ.