Thanks Steve, hi Martin, We can always rely on the technical community for a calm and reasoned way through system failure :-)
Great to have your expertise on tap, guys. On 06/09/10 18:34, Martin Bähr wrote: > On Mon, Sep 06, 2010 at 11:27:52AM +1200, Steve Holdoway wrote: > >> The Pacific plate is constantly moving relative to and under the >> Australian one. This is what has created the Southern Alps where the >> Pacific plate gets deep enough under the Australian one to melt ( known >> as a subduction zone ). This is the opposite from the North Island, >> where the volcanics are on the eastern side. There's a big tear through >> the Cook Straits because of this contrariness. >> > interesting. just checked a map. > so north-island is on the australian plate, but south island is not. > do i sense a pun here? > > greetings, martin. > ps: news of the quake found their way north. hope you all are well... > It takes a lot for Canterbury to feature on the global radar, "green and pleasant land" that it has been. But this is obviously 'it'. - But what? From the Earth's youngest land mass.. Last night's 5.4 magnitude swarm, and this morning's (repeated) 6.? warning must be focusing minds.. From atop our "extinct" local volcano, one feels these gestated 'gentle jolts' as quite worrying - like huge churning gears below ground. But on the Canterbury Plains the effects are simply terrifying, and perhaps justifiably slow. - Get out your atlas and yesterday's Press please. Horomaka / Banks Peninsula is formed by twin collapsed cones of the same volcano - some 120 million years old, from memory. These preceded the upsurge of the Alps, caused by the plate collision that Steve has documented above, which rainfall erosion over millenia grounds down into huge alluvial fans, forming one long contiguous plain. The Canterbury Plains has many large alpine rivers, reaching east - to wash contact north and south of Banks Peninsula. The Waimakariri outlet historically varies its sea outlet north and south of Banks Peninsula, forming both Te Waihora / Lake Ellesmere and the Christchurch Estuary through its larger effect. Take a high aerial view via your atlas, blank out the Alps and Plains, and focus on Horomaka / Banks Peninsula. One large step back further in time, before these volcanic twins - that later became Lyttelton and Akaroa harbours - another land mass was formed by their parent, in the open prehistoric sea - Rekohu / the Chatham Islands. Did that volcanic event precede the formation of the entire North and South Islands? - Steve should be able to tell us. The point being to anticipate the next westward outburst of this important volcano, in the next seismic-peak period. Now go to yesterday's Press, about page A4. There is a detailed graphic of the quake epicentre and the (brand new?) fault it has revealed. Strangely, there is even a quite perfect roading triangle mapped around the epicentre, which features as its apex.. Now draw a joining line between quake epicentre, to Horomaka, and on to Rekohu. Is it horizontal and straight? I am supposing that it is. If our subterranean rumblings fail to cease, that is a most unusual sign. We could fear the worst. All of central Canterbury may need evacuating, at the least.. ~ Can Ruamoko ever be soothed back to sleep, within his infernal depths? ... http://wiki.answers.com/Q/Who_is_ruamoko Stay safe, -- Kind regards, Rik Tindall +64 03-332-1069 or 027-406-0077 Candidate for Hagley-Ferrymead community board, Burwood-Pegasus ward councillor& Christchurch mayor ~ www.OurWaterOurCity.org Canterbury Regional Councillor in exile (ECan), Christchurch East www.ecaninexile.wordpress.com + www.SaveOurWater.org.nz : 2007-10 Canterbury Civil Defence and Emergency Management portfolio chair pp SoftwareFreedomDay.org team Christchurch _______________________________________________ Linux-users mailing list [email protected] http://lists.canterbury.ac.nz/mailman/listinfo/linux-users
