Canadian researcher joins Chch seismic team

When Canadian researcher Joanna Cooper began geophysics PhD studies at the University of Otago last year, she never dreamed she would soon be carrying out seismic hazard identification work in Christchurch, after a devastating earthquake.

Miss Cooper, who has an MSc degree in geophysics from the University of Calgary, Canada, recently returned to Dunedin after spending several days in Christchurch working intensely to gather seismic data, using a specialised truck-mounted vibrating device.

About 12 days ago, she had travelled to Christchurch as part of an international team of scientists, including four from Canada, who are striving to better identify future earthquake hazards in the city, including clarifying the location of nearby fault-lines.

This research followed the February 22 magnitude-6.3 earthquake, which killed more than 170 people in Christchurch and caused widespread property damage.

This is one of several related research projects which aim to strengthen earthquake hazard identification, to help with the future rebuilding of Christchurch, and to better guide engineers and planners in protecting the city's residents.

The latest phase of land-based seismological research - following earlier ship-based testing off the Christchurch coast - is also part of the Natural Hazards Platform, a collaborative research programme involving GNS Science, other crown research institutes and several universities.

Miss Cooper may be studying a long way from home, but earlier this month found herself unexpectedly using specialised truck-mounted seismic testing gear from her alma mater, the University of Calgary, in Canada.

This equipment - usually used for training Canadian geophysics students, including Miss Cooper - had been flown by cargo plane to Christchurch as part of international efforts to help after the February quake.

The "vibroseis" truck sends low-frequency vibrations several kilometres into the Earth's subsurface layers, and uses geophones - electronic receivers of seismic vibrations - and computers to build up a map of subsurface structures, including signs of fault-line activity.

Miss Cooper also found herself working again in Christchurch with one of her Canadian MSc co-supervisors, Calgary University geophysics Prof Don Lawton, who is New Zealand-born.

Miss Cooper, whose PhD work is supervised by Otago University seismologist Dr Andrew Gorman, said she enjoyed the Christchurch research, which involved three "lines" of consecutive test sites, up to about 8km long - one at Darfield, another in central Christchurch, and the other near New Brighton.

"It's great to be able to help out and also to do so in my area of expertise." And she was well aware of the huge cost, including in human lives, of the February quake.

"You can't walk in a city that's had that kind of damage and not be affected by it."

john.gibb@odt.co.nz