Clues to Nelson's ancient history are embedded in the rock formations at Magazine Pt. The horizontal layers of rock which provide hours of entertainment for rockpool fossickers are a window into New Zealand's geological past, and a relatively calm period between violent land upheavals.
Nelson Mail photographer Marion van Dijk followed Nelson geotechnical consultant Mike Johnston on a trip dating back about 23 million years.
Dr Johnston explains that the rocks below Magazine Pt are the result of a geological process which began 23 million years ago, and finally became a landform eight million years ago.
Sediment consisting of sand, silt and mud flowed down the coast into deep water and 23 million years ago settled into a graded layer, which solidified into rock. The process was repeated again over several million years until it was uplifted about 8 million years ago to form land. In the process the layers, or "graded beds" were tilted to the east. The land was then eroded before another period of tilting, or mountain-building, created the formations we see today.
"Nelson's early settlers came across them, and presumably Maori observed them," Dr Johnston said.
In 1859 German geologist Ferdinand von Hochstetter visited the site, which also contains coral, bivalve and gastropod (snail) fossils embedded in the sandstone.
- © Fairfax NZ News