A 3 minute interview on RadioNZ on 30 January 2024 caught my attention — Research shows huge tsunami hit Kāpiti | RNZ. Further exploration gave more detail from other sites:
From What scientists discovered in Kāpiti: ‘This was no small tsunami’ - NZ Herald:
Scientists have uncovered evidence of a massive tsunami that slammed into the North Island’s west coast some 600 years ago, raising intriguing questions about what might have caused it.
The event, thought to have occurred in the mid-15th century, is among dozens of prehistoric “paleotsunamis” around the country that researchers have documented through ancient geological deposits.
In the latest case, a team of researchers were working on dune systems on the Kāpiti Coast when they found evidence to suggest sand had suddenly and violently been shifted inland at some point in the past.
After measuring the extent and height of the dunes, the team dug trenches to explore material beneath it, before taking samples of old tree stumps submerged in a nearby wetland formed when the sand blocked drainage.
Further analysis and radiocarbon dating allowed them to reconstruct the environment – including a large podocarp forest and sand dunes that offered Māori inhabitants a refuge from the wind, as indicated by old shell middens - as it would have appeared in the 1400s.
More interestingly, they were able to show how this area was instantly transformed by an event that drowned the forest, wiped out the dunes and seemingly caused Māori to abandon the coastal area, with no further signs of occupation after that date.
The research is available at: Reconstructing a palaeotsunami: Geomorphological and cultural change associated with a catastrophic 15th century event, Kāpiti Coast, Aotearoa/New Zealand - Jodie McClintock, James Goff, Bruce McFadgen, 2023.
