Drilling off Gisborne to study silent quakes

  • Breaking
  • 07/07/2015

By Jacob Brown

Scientists baffled by a mysterious type of earthquake are eyeing up the North Island's east coast for groundbreaking research.

Called silent earthquakes, they're considered one of the most important discoveries in seismology over the past 15 years, and it turns out the ocean off Gisborne is the perfect place to study them.

One rig has drilled more than 1300 holes in the ocean floor since 1985 – not for oil, but for earthquake research – and New Zealand waters could be next.

Scientists say it's the perfect place to study "slow slip events" – earthquakes that take place over weeks and months.

"We don't understand what the physics behind them are," says Dr Laura Wallace of the University of Texas. "We don't know why they happen. There's a lot of different theories for why they happen, and we're hoping some of the results from this project will illuminate that."

The project will focus on an area 40km east of Gisborne. Three separate drill sites are planned, each of them up to 1.5km deep.

They'll straddle the Hikurangi Trench, where the Australian and Pacific plates intersect. That's directly above where silent earthquakes take place.

The world-first proposal would start in 2018 and involve scientists from eight countries. It has scientists excited because the results could be groundbreaking.

Drilling for science is not without risk, but it is permitted by the Environmental Protection Authority.

Researchers have been talking with community groups and local iwi and are confident it will go ahead.

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source: newshub archive