Scientists at fault over data error
Scientists monitoring New Zealand’s largest faultline have fished up monitoring instruments with no data on them due to programming errors.
As part of ongoing research into the Hikurangi subduction zone off the North Island’s east coast, seismic monitoring instruments are being placed on and removed from the ocean floor.
Dr Samer Naif, an assistant research professor at the LamontDoherty Earth Observatory at Columbia University, who is leading the current voyage, said three instruments recently fished up by scientists had no data on them.
‘‘Three of the 170 ocean-bottom electromagnetic (OBEM) receivers . . . were set to the wrong date.’’
The instruments record electric and magnetic data. The data collected on the current voyage would be used to construct an image ‘‘like a medical MRI’’ of fluid conditions below the seafloor.
Fluid conditions affect the likelihood and type of earthquakes that occur at faults.
The team lost about 2 per cent of the overall data.
‘‘We were certainly disappointed when we realised what had happened, as prior to this event we had a perfect track record,’’ Naif said.
One person was tasked with setting the recording date, and a second person checked the settings to confirm correctness.
‘‘This was a case of user error, where the date was accidentally programmed with the wrong year. It happened at a time when we were trying to work really quickly to avoid a weather front with rough seas and galeforce winds forecast to arrive later that day,’’ Naif said.
‘‘We now have a third person checking the time and date prior to the release of the instrument when we have to deploy the instruments rapidly – one every half an hour or less.’’
The scientists had brought spare materials, and designed the experiment with enough contingency time in case of such events.
‘‘This means we will be able to luckily recollect the lost data within the next few days . . . we are on track to return to port having collected at least 15 per cent more data than originally planned.’’
The voyage, on research vessel Rodger Revelle, was being led by the Lamont-Doherty Earth Observatory, and funded by the United States National Science Foundation.
East Coast LAB project leader Kate Boersen said the Hikurangi subduction zone was poorly understood.
‘‘It is great to have international scientists working alongside New Zealand scientists to learn more about our earthquake and tsunami risk.’’