Macca to dodge tsunamis?

 

Last week I heard on the ABC that the Macquarie Island research station (Macca) may be moved to higher grounds because of the risk of tsunami.

Back in 2000 Macca was my home away from home! I even remember a minor earthquake there and then. The station is built on an isthmus between a cape called North Head and the rest of the island which consists mainly of a plateau at about 200m of altitude. When the westerlies blow about 70 knots, it is not uncommon to see a big wave cross the isthmus. This annoys the elephant seals a bit, but a tsunami… I can’t remember this being mentioned during the 9 months training or the year I spent there.

A tsunami is a different kind of wave. It happens when a very large volume of water suddenly moves up from the bottom of the sea or lake. This kind of movement may be caused by an earthquake, a sub-sea landslide, a volcanic eruption or a meteorite impact.

Located 1600km South-East of Hobart, Macca sits on the boundary between the Pacific and Australian tectonic plates. Motion along this boundary can cause major earthquakes. And given the local submarine topography, even a minor earthquake can cause a landslide, the second most common cause of tsunamis.

The Antarctic Division plans to refurbish the station as it is getting a bit old. But according to marine geophysicist Mike Coffin, it would be a better idea to move it to higher ground.

References:

Tsunami definition and basic facts
http://geodesy.unr.edu/hanspeterplag/library/projects/eseas_white/Tsunami.htm

Macquarie Island concerns
https://www.abc.net.au/news/2021-08-04/quake-tsunami-concerns-for-macquarie-island-expeditioners/100342756