Seafloor cables detect Pacific Ocean earthquakes

The team is performing ultra-sensitive optical measurements, converting a branch of the Southern Cross Next seafloor cable, which connects New Zealand to Australia, into an array of sensors for earthquakes and ocean currents. The technique uses the optical fibre inside the cable as the sensing element and gathers environmental data from the seabed, where no other permanent sensors exist.

In a statement, Giuseppe Marra, principal scientist, NPL said: “We are very excited to have started detecting earthquakes and ocean currents in the Tasman Sea. This is the very first test of this technology in the Pacific Ocean and the waters surrounding New Zealand are the ’perfect laboratory’ to demonstrate the full potential of these…techniques for Earth sciences and coastal population protection.”

The Pacific Ocean is a highly seismically active area and since the start of the measurements in October 2024, the team has recorded over 50 earthquakes, with an epicentre from tens to hundreds of kilometres from the cable.