Using the combined benefits of genetics and geology, a team of researchers from the University of Otago has discovered and concealed a previously unknown coastal uplift area in Raranga, Marlborough. This unknown region of earthquake uplift was discovered using a combination of laser mapping and new data from algae genetics.

Co-author Professor John Waters, from the Department of Zoology, says the study provides new insights into changes in Aotearoa’s landscapes and the history of recent earthquake effects.

“In a geologically well-studied country like New Zealand, there is a lot to learn about our history of earthquakes and landforms,” he says.

An article just published Journal of the Royal Society InterfaceIt used LiDAR mapping (a remote sensing technology used to model ground clearance) and genetic analysis of bull kelp from an elevated part of the shore.

The team discovered a previously unknown area of ​​elevated rocky shoreline – lava about 1 m above sea level – and a genetic abnormality in the algae beneath that lava. Kelp genetics indicate that the species became extinct in the region after the earthquake before being replenished by algae moving 300km south.

The “lava” rising above the waterline in Raranga originally formed at sea level but was raised by an earthquake. Credit: University of Otago

The group believes the responsible earthquake occurred about 2,000-3,000 years ago, indicating the moss’s potential to record geological events.

“This area is located near a known active fault and several past major earthquakes have been well appreciated by other researchers, but this coastal uplift area was previously unknown – the evidence for this is very clear and now has the opportunity to examine it closely. Rarangi is also a very popular summer swimming spot. The place is not obscure or remote, and evidence of coastal uplift is hidden from view,” says Professor Waters.

The research is the latest result of the group’s Marsden-funded project to assess the impact of earthquakes on coastal species.

“Our study uses a combination of genetics and geology, and it’s very exciting that these combined approaches allow us to locate a previously unknown coastal uplift in New Zealand.” serves to emphasize once again.” Source