Trip to GNS

Whoever said that being retired leads to a very  busy life wasn’t kidding - we have recently joined the local 60’s Up group.   (They took our money and we were joined up straight away – no questions asked!)  The Sixties Up Movement is a body of senior members of the community made up of those who are active, usually no longer in full time employment, who meet in local branches to find new friends and activities.  One of the Movement's main objectives is to offer opportunities for members to maintain and expand their minds and bodies with social communication and educational and recreation activities.  We recently went on our first bus trip with the group, down to the Hutt Valley to GNS Science. 

All aboard the bus

As former Hutt Valley residents we can remember when this building used to house the National Film Unit.  

Our speakers for the morning were Katie and Delia, who have an impressive range of academic achievements between them.  They welcomed us to the theatre in the facility and presented a slide show of their respective areas of research. 

A welcome to our group on the big screen

 

GNS Science (formerly known as the Institute of Geological and Nuclear Sciences)  is a New Zealand Crown Research Institute.  It focuses on geology, geophysics including seismology and volcanology, and nuclear and isotope science, and carbon dating.  As well as undertaking basic research, and operating the national geological hazards monitoring network, GNS Science is employed, both in New Zealand and overseas, by various private groups (notably energy companies), as well as central and local government agencies, to provide scientific advice and information.

The long drawn out process of Geological mapping was explained.  With many field trips made to collect rock samples and take measurements, then back to the lab to plot and collate huge amounts of data, the geological map is slowly built up.  Helicopters are used these days to drop the scientists off in remote locations, and bring back the heavy rock samples.  Things were quite different in the old days, we were told.  Geologists would go into the field with a wooden case of whisky, consume the contents while they were camped out in rugged terrain, and fill up the empty cases with rock samples.

 

Whisky box from Alexander McKay Field Exhibition

Research into geological hazards is a big part of the work done at GNS.  The Tongariro eruption in 2012 opened up a new fissure and researchers advised that the popular Tongariro Crossing Walk be closed for several months while the area was monitored.

Te Maari 21/11/2012 eruption column taken from Emerald Lakes.

Much work has also been done by GNS on ground surveys after the disastrous Christchurch earthquakes in 2011 and 2012.  The previously unknown fault that ruptured under the northern edge of the Port Hills was sloping back and pointing straight at Christchurch. When it ruptured, most of the energy was directed north-west toward the city.  A recently discovered physical phenomenon explains this observation. As the huge early pulses of energy travelled through horizontal layers of the earth beneath Christchurch, the weaker upper layers travelled farther upward than the stronger lower ones, and so separated from them. When these upper layers fell back under gravity, they ‘slapped’ against the lower layers coming up again, producing very high impacts.  This effect also helped to explain the widespread liquefaction in Christchurch. As the layers separated, water in subsurface layers became less bound in soils. When the slapping occurred, large amounts of water was forced up to the surface.

Stuck in a sea of liquefaction

We all felt that our minds had been expanded after the presentation given by the young researchers, our brains were trying hard to take it all in!  Next stop was to the Petone Working Mens Club for lunch, and once again we had a special welcome, with tables reserved for our group.

There was plenty of choice at the Bistro, and all very reasonably priced too.  It was a great day, and it was noted that several nodded off during the bus trip home.