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DISCOVERDISCOVERDISCOVERDISCOVERDISCOVER UNDERSTANDUNDERSTANDUNDERSTANDUNDERSTAUNDERSTAND APPLYAPPLYAPPLYAPPLYAPPLYAPPLYAPPLY ISSUE NO.4 AUGUST 2013 globeMAGAZINE including: SW eeT Win FOR HOneY inDUSTRY Isotope science throws honey a lifeline NOVEL USE FOR RADIOCARBON Measuring CO2 emissions with radiocarbon EARTHQUAKES anD BULK WATER SUPPLY A wakeup call for Wellington’s water supplies globeMAGAZINE CARBON CALLING PH OTOGRAPHY: Radiocarbon dating is one of the most widely known scientific techniques. However, Lloyd Homer, Margaret Low, less well known is that New Zealand scientists were at the forefront of its development Heidi Roop, Julian Thomson, in the early 1950s. As a result of this trailblazing work, this year the New Zealand Tourism Bay of Plenty, radiocarbon community is celebrating the 60th anniversary of the publication of the The Dominion Post. first radiocarbon dates in 1953. Our Rafter Radiocarbon Laboratory, where it all began, is the oldest continually operating radiocarbon lab in the world. DESIGN: Darren D’Cruz Dating with radiocarbon acts as a kind of egg-timer to measure the time that has elapsed since an organism died and stopped taking in carbon from its environment. COVER PHOTO:. It works for objects that are up to 50,000 years old. Sixty years ago, the pioneer There are about 380,000 bee- developers knew they were on to something big, but they may not have realised that hives in New Zealand. Isotope radiocarbon would become a cornerstone scientific technique for dozens of industries science supports the bee and scientific disciplines. industry which, directly and indirectly, contributes about Applications include dating antiquities, atmospheric studies, archaeology, climate $5 billion annually to the research, oceanography, geology, earthquake, volcano, and tsunami research, marine New Zealand economy. biology, and tracing the movement of carbon atoms through the environment for carbon Story pages 6 & 7 accounting. For example, radiocarbon has given us the dates of the more recent Taupo The information in this publication eruptions, and dates for the last 24 ruptures on the Alpine Fault in the South Island – may be copied and distributed to providing a remarkable 8000-year history of activity on this fault. others, provided GNS Science is acknowledged as the source of the In spite of the fact that there about 140 radiocarbon laboratories in the world, the Rafter information. Under no circumstances Laboratory, with its recently upgraded accelerator mass spectrometry facility, has may this information be changed carved out a special niche. This is because of its continual drive to improve precision, without the express permission of its commitment to prompt turn around times, and its willingness to take on new or GNS Science. challenging dating assignments. It has become a preferred facility for those who have special requirements such as high precision or small sample size – just a few milligrams ISSN 1179-7177 (Print) of carbon. Its precision is now routinely plus or minus 20 years. It has also expanded ISSN 1179-7185 (Online) its capabilities to measure beryllium-10 and aluminium-26, in addition to carbon-14. This versatility ensures it contributes to a wide range of science applications in GNS Science, Te Pū Ao, is the New Zealand. New Zealand science organisation that focuses on geological resources, More recently Rafter Radiocarbon staff have successfully trialled a new application – environmental and industrial isotopes, measuring industrial greenhouse gas emissions. We thank Vector who generously and geological hazards. By applying its allowed us access to their Kapuni facility for this project. Outlined on page 9, it shows scientific knowledge, GNS Science there is now an independent technique to verify self-reporting of greenhouse gas creates wealth, protects the emissions by industry. The project has strong parallels with one of the early applications environment, and improves the safety 2 of radiocarbon in New Zealand - the pioneering measurements of atmospheric carbon of people. dioxide at Baring Head near Wellington. This long record of measurements has, over many decades, been a vital contributor to global atmospheric studies and climate models. GNS Science employs 390 staff and has offices in Lower Hutt, Taupo, and John Callan Dunedin. Editor Copyright © 2013. issue 4 C ontents 4 4 GPS SURVEY Keeping track of land deformation 6 S WEET VICTORY FOR HonEY Isotope science throws honey a lifeline NOVEL USE FOR radIOCARBON 8 Measuring CO2 emissions with radiocarbon 10 10 Fa ST daTA FOR BAY OF PLENTY I nstant access to 3D geology and groundwater information 12 T SUNAMI STUDY Mitigating tsunami risk in coastal development 14 SP LO E FAILURE S tudy promises to reduce the risk of building on slopes 16 LakEBED SECRETS 14 L ake Ohau sediment a key to understanding climate patterns 18 Ear THQUAKES and BULK WATER SUPPLY A wakeup call for Wellington’s water supplies 20 T HE BIG ICE MELT 30,000 years of detailed Antarctic climate history revealed 22 EdA UC TION OUTREACH S cience rocks at school geocamp 16 23 PUZZLE Crossword globe August 2013 urvey S PS G Kee PING TRACK OF LAND DEFORMATION Each summer our geodesists set off for different parts of New Zealand with a battery of GPS receivers to get precise measurements of the way the land surface is deforming due to tectonic forces. Different parts of New Zealand are moving at different rates and in different directions. In some places this movement is increasing the stress in the earth’s crust, and in other places it is releasing stress. Annual summer GPS campaigns boost During February 10 people, including Scientists generally survey one area the measurement capability of the staff from Land Information NZ, worked each year, so the entire country is GeoNet-operated permanent GPS in pairs to undertake an 18-day GPS re-surveyed every eight years. instrument network. The denser measurement campaign of 164 survey 4 instrument coverage provided by the marks in the lower North Island. This However, they carry out extra surveys in short-term campaigns delivers more was part of a long-term programme areas where elevated geological activity detailed information in the gaps of summer campaigns, for which is occurring or where deformation between the permanent stations for geodesists have portioned New Zealand assessment is particularly complex. For deformation and hazard modelling. into eight zones – four in the North example, there have been numerous Island and four in the South Island. surveys in the Canterbury region in the wake of the September 2010 and February 2011 earthquakes. issue 4 Stewart Bennie (left) and Neville Palmer make a GPS measurement near Moonshine Road, north of Wellington. Each summer they make more than 100 GPS measurements in a different part of the country to determine how fast the surface of New Zealand is deforming due to tectonic forces. Photo: Margaret Low Repeated measurement over time Horizontal positions have an accuracy phenomena such as volcanism, enables scientists to keep a detailed of 3-4mm while vertical positions are geothermal activity and movement of track of the way our landscape is accurate to 6-9mm. They show that, in freshwater in aquifers. While geodesists deforming. Deformation rates are not general, much of the Wellington region are careful to filter out effects from smooth and it is common to detect is moving southwest at about 45mm-a- these phenomena, those data are fluctuating rates over a period of year relative to Australia. There are also useful to other scientists in related months or years. small changes in height as the region is research areas such as volcanology, gradually squashed horizontally by geothermal energy, and groundwater. The survey marks that contribute to this tectonic forces. long-term project range from well- Data acquired from short-term known trig stations to metal pins set in Each of the eight zones has its campaigns feeds into numerous concrete or rock outcrops in remote peculiarities and challenges. The Taupo aspects of earthquake science and locations. The GPS instruments are left Volcanic Zone, in the central North hazard modelling. on site for 48 hours of continuous data Island, is generally measured more recording and then shifted to a new frequently as the geological processes Contact: Neville Palmer, 5 survey mark to repeat the process. are occurring faster and there is more GNS Science, Lower Hutt Combining the accumulated data from variation than in other regions. There is ([email protected]) each site with specialist processing more active faulting, and the crust is techniques enables a very precise thinner and moving relatively fast. But location for each survey mark, specific this brings challenges to geodesists in to the date of the observation. the form of ‘unwanted signals’ from globe August 2013 weet victory for honey ISOTOPE SCienCE S THROWS HONEY A LIFELine Isotope science and the honey industry have teamed up to find out why genuine New Zealand honey was failing an internationally accepted test that detects adulteration with cane sugar. The test failures represented a cloud hanging over the industry until GNS Science was able to show that the international test was inadvertently biased against some New Zealand honey varieties, especially our biggest export honey, Manuka. The honey industry typically exports Prior to 2010, New Zealand honey Importing countries are slowly adopting product worth about $110 million products were not routinely tested on the new testing criteria. Prior to these annually with Manuka honey making up arrival in destination countries. However, changes, beekeepers were faced with the bulk of this. The scientist leading the overseas countries became more either holding on to their high-value project, Karyne Rogers, uncovered the vigilant with testing in 2010 in the wake Manuka honey, or blending it with other anomaly, and instigated an assessment of a sharp increase in honey fraud lower value honey to bring down its of testing procedures in government originating from Asia.