Slow earthquakes discovered in NZ
The researchers don't know what these slow earthquakes mean for the fault line, but suggest further work is needed to help predict hazards. Image: -hakusan-/iStockphoto Victoria University scientists have discovered that slow, creeping earthquakes take place deep beneath the Alpine Fault on the South Island of New Zealand's West Coast, which is regarded as New Zealand’s most hazardous fault line.Scientists have been puzzled for decades by an apparent absence of earthquakes in the central section of the Alpine Fault, between Fox Glacier and Whataroa Valley 50km to the north.But a study led by Victoria University Geophysics Professor Tim Stern has shown the area often experiences seismic tremor, or a series of slow, creeping earthquakes that each last up to 30 minutes.Professor Stern says that the seismic tremor is located at depths of 20 to 45 kilometres whereas regular earthquakes are mainly confined to the top 10 kilometres of the Earth’s crust.It’s only...