On 1 March 2011 02:01, N. T. wrote: > =A0IVP wrote: >> >> Christchurch is particularly prone to liquefaction during tremors >> because of the underlying geology, and that allowed for more >> damage than might have happened on solid ground >> >> http://www.guardian.co.uk/weather/2011/feb/23/new-zealand-christchurch-e= arthquake-geology >> >> On the surface of course it's a very nice place to live. Plains, >> hills, harbours, rivers etc >> > > I am not getting what's going on to South-West of Christchurch now: > > 3.3M, depth: 0km 28/2/2011 20:22 > http://www.christchurchquakemap.co.nz/ > > Zero depth. Would the next be negative depth? > No humor or sarcasm, just wondering what's that? How does that feel to > be there? This seems to be the place where September quake line > crosses latest quake line. > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > Yes, that one was "0" depth which means closer than about 2.5km deep. The epicentre was about 6km away from home, so we felt it, but no worse than many of the other aftershocks we're getting. One thing to consider is that the epicentre is the surface location above the initiation point (isocentre ?) , the centre of mass movement can be several km from this and the actual movement magnetude can be focussed or dissipated by the type and location of other features. It seems to be a very complicated issue. We are about 8km from the main city centre that suffered last Tuesday, and yet had no damage (that we know about) and never lost water or power. Just lucky. Richard P --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .