Posts by craigm
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I ride most days for commuting - about 9kms each way. Taupo to Wairakei. I have the luxury of either Mtn bike track or main road (SH1 - but with nice wide shoulders for most of it.) I ride a road bike with clipless pedals (or mtn bike with spd's) and usually take a change of clothes in my bag, along with lunch etc. luckily dress code at work is jeans / tee shirt, so no worries with wardrobe issues.
Used to be totally lyrca for shorts, but this summer have been wearing some groundeffect baggy shorts. Totally fine for the 9k and a bit more stylish if you want to stop off in town for something on the way home.
We have a shower at work, so i just wear a sports tee shirt in summer or in winter it's lyrca cycle shorts with groundeffect daddy long legs tights over the top. then a merino top (or 2 if it's real cold). Then over that a groundeffect Flash Gordon jacket. Just got my 2nd one of those after wearing my previous one for 10 years! Then if it's super cold a full face ski mask. It can get to -4C in winter here so full cover is totally necessary.
Gloves, always. In summer fingerless gloves, in winter full finger gloves. These are my favourite, ninja ice gloves http://www.argus.co.nz/mainmenu99/cat113/Freezer+Gloves/p767/Ninja+Ice+Gloves.html.Lights, just got one of these for winter. super cool!
http://www.youtube.com/watch?v=ix2sNGhXJ2cHelmet, always.
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Hard News: Cheer Germ, in reply to Sacha,
except for the times when he didn’t quite make it…..<wince>
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where he said that earthquakes were most likely to happen at the full moon, and the new moon, and two weeks either side. And I guess he’s right, technically
2 weeks either side of a full or new moon covers the entire month! So basically he "predicts" an earthquake for any day of the year!
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I've been lucky enough to visit Eyjafjallajokull in 2008, my personal pronunciation guide is "eh-a-fiatla-jokult" - gottal stop on the last "t".
The floods that come out of the glaicers -from all the melting ice are call jokulhaups.
Anyway pyroclastic flows are the result material collapsing out of an ash column - they're also called pyroclastic density currents and they can happen at a range of scales. The whole cloud doesnt have to collapse all at once, but bits can fall out of it as the main cloud continues to rise. Ngauruhoe in the 70's had small ones that only made the foot of the cone - whereas other ones (such as from Taupo) travel hundreds of kilometres - the deposit is then called an ignimbrite and if it's hot enough when it lands it will weld together into a solid rock. What you might be mistaking for a pyroclastic flow in the Auckland video is a base surge which is kind of a low angle PDC that comes straight out of the vent at an angle rather than going up in a cloud and then collapsing. A base surge is the result of interaction of magma and water, so if an Auckland volcano erupted in the harbour, a base surge is what you'd get.
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I rather like my own suggestion for that sign on the hill next to the airport.
whoop whoop pullup!
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unfortunately !!!??!!!!
You sound disappointed.
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hah! poor choice of words, *luckily* i meant.
@Yamis. The Waitaks are indeed made up of an old volcano that once existed to the west of AUckland. It is part of a chain of long dead volcanoes that exist offshore from Kaipara to the Waitak's. THey were formed when the plate boundary was much further west than it is today (may somewhere around where AK is today - except of course Ak didnt exist then). THat was about 20million years ago (20Ma). Around 10Ma the plate boundary moved east (rotated clockwise) and formed the Coromandel Peninsula. Then around 2-3Ma it moved east again and started to form the present day Taupo Volcanic Zone. East Cape is continuing to rotate clockwise and eventually the next volcanoes in NZ will probably form somewhere around W(h)anganui - but we're talking millions of years....
The Auckland volcanic field is unrelated to the present day (or past) plate boundary. It's what's called an Intraplate volcanic field, ie a volcanic field that forms within a plate away from a boundary. There's another one in Northland - Kaikohe that last erupted only 2ka. The Mumbai Hills are an older version of the auckland field, it's thought that activity moved nth from the Bombays which were active about 1Ma to the AVF which started about 250ka.
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@rich
unfortunately that La Palma story is somewhat exagerated......
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@Chris - thanks !
@ Hilary
The best place to look for overseas stuff is the usgs website.
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html
they look after the global seismic network which is able to locate large earthquakes any where in the world. Our NZ network cant locate events too far outside NZ with any accuracy so we rely on the GSN for that info. A couple of NZ stations contribute to the global network. There's a link to it on the Geonet website under the Earthquakes tab - links.
@lucy
havent actually seen that TV3 program ...probably an omission on my part. bUt the estimated shaking intensity in the Wellington CBD from the 1855 quake is MM10 on the Mercalli scale. This is described as "Many buildings are damaged and most weak buildings are destroyed."
http://www.geonet.org.nz/earthquake/modified-mercalli-intensity-scale.html
Volcanoes are more my thing anyway ;-).
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@Russell
assuming you're not meaning the pending Phoenix game....
http://www.gns.cri.nz/wellingtonfault/
The good news is that recent GNS research has shown the Wellington Fault ruptures more like every 900 years (on average) not every 600 years as previously thought. The last big one was about 300 years ago ,so plenty of time yet....
But that's just the Wellington fault. The nearby Wairarapa Fault last broke in 1855 and caused a magnitude 8.2 quake which would still be pretty, shall we say, exciting, in the wellington CBD.
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@Hilary
The energy is derived as follows. In Chile the Nazca plate is moving eastward under the Sth American plate at the rate of about 70mm per year. This is along a plate interface of several 1000km's. Now not all of this interface moves freely, parts of it are "stuck" and dont move, yet they are still being pushed together at a rate of 70mm per year. Over hundreds of years this 70mm of movement is accumlated as a strain deficit in the plate boundary . 100 years = 7m of accumlated (yet not realised) movement. Eventually the accumlated strain builds up to be greater than the friction stopping the plates from moving freely and then the whole lot lets go causing massive earthquakes. In NZ we have a similar situation off the east coast of the Nth Island where the Australian and Pacific Plates meet. There are zones along the plate boundary between Gisborne and Wellington that are locked and arent moving at the rate they should be moving compared to the rest of the interface. We can tell all of this through very precise continous GPS measurements which show which parts of the country are moving at what rates. What we cant tell however is how much strain the locked interfaces are able to accomodate before they release. We can however map out roughly which parts of the plate boundary are more strained than other and therefore more likely to fail.
There are also things called "slow earthquakes" in which the accumulated strain is released over the period of several days or weeks (as opposed to seconds in a earthquake). Several of these have happened off the East Cape in last 10 years since we have had the technology to measure them. In the slow earthquakes you might get 20-30mm of movement occuring slowly over several days (normally it would take a year or 2 for this amount of movement), which because it is so slow doesnt cause an actual earthquake. This amount of movement equates to something like a magnitude 6 earthquake. So slow earthwquakes do a lot for preventing bigger earthquakes. http://www.gns.cri.nz/news/release/gisborne.html
The moon has very little effect, as even though it is large it is very far away so its gravitational effect is very small.
disclaimer: i work for GNS in GeoNet... :-)