Explosive earthquake research to begin in new year
Scientists researching New Zealand’s largest fault line are preparing for an explosive start to the new year.
In Napier on Wednesday night, researchers from GNS Science and the National Institute of Water and Atmospheric Research (Niwa) discussed their latest findings and the future of their ongoing monitoring of the Hikurangi subduction zone off the east coast.
Dr Dan Bassett, of GNS Science, said 900 seismometers would be deployed between Gisborne and Whakata¯ ne as part of the next phase of the organisation’s Seismogenesis Hikurangi Integrated Research Experiment (Shire) project.
Scientists would then detonate five dynamite shots within shallow boreholes to generate seismic energy.
They were hoping to get under way between February and March next year, with Bassett saying consultation with communities, landowners and iwi was ‘‘all going well’’.
‘‘This energy from the shots will travel down to the deeper portions of the [Hikurangi] subduction zone beneath the Raukumara Peninsula and travel back up to the surface to be recorded by that dense seismometer array,’’ he said.
The project intended to fill ‘‘blaring gaps’’ in the data for the transition between the southern portion of the Hikurangi, where the plate was strongly locked, and the region to the north, where the plate was creeping.
Scientists carried out the same experiment across the southern portion of the Hikurangi in 2009, Bassett said.
Before then, scientists ‘‘didn’t really have good knowledge of the deeper portion of the subduction interface’’ and the data gained gave them a ‘‘much more detailed picture’’ on things, including the geometry of the Pacific Plate, and slow-slip earthquakes.
GNS Science’s Dr Laura Wallace spoke of the organisation’s rolling deployments of sea floor-monitoring instruments off the east coast, and the future possibility of permanent instruments.
‘‘Our development of sea floor instrument capability we hope will position us to be able to start going down a road of having more permanent, continuous, monitoring out there that we can actually use in real time to keep our finger on the pulse of what’s happening and what that means for earthquakes.’’
The research had received more than $60 million in international science funding and investment, Wallace said. ‘‘We’re really excited, because [of] the studies going on over the next several years, we’re going to have a really big step change in our understanding of this plate boundary that you guys are all living on.’’