Rust Fossils

I first stumbled across this bed of what appears to be rust fossils about 20 years ago. They are only visible at low tide. The place is Kakanuni about 10 kms form Oamaru. My theory on these is, many years ago this area was used as a dumping ground for old unwanted railways bits. Because this is at the bottom of a cliff it was easy to to just shove the rubbish over. The continual tumbling of the waves and rocks eventually pounded, corroded and fused the bed rock and rubbish together. This whole area is part of an extinct volcano around about 35 million years old.
I took these snaps recently. I met a geology student taking measurements for part of his course. He told me how old the area is.