new caledonia trip

[Bartos Fam]

Here is a trip report from an area that rarely is mentioned in this forum. Last December we had a family trip to the islands of Lifou and Mare in New Caledonia, in the south west pacific.  These islands are raised coral atolls, and due to their location at the point where the Australian Plate meets the Pacific Plate the islands experienced an uncommon amount of uplift, leading an unusually large amount of exposed underlying limestone.  Lifou is the world’s largest  raised atoll, it is about 80km/50mi long, Mare is slightly smaller but  is probably the second or third highest uplifted atoll reaching up to 138m above sea level. 

The other unique thing about these islands is the abundance of living fossils, in the form of Arucaria trees.  The Arucaria genus dates back as far as 200 million years, of the 19 species remaining today, 13 are only found in New Caledonia.    These trees give a distinctly prehistoric feel.  New Caledonia  is also the only place in the world were the Amborella plant can still be found, it is the closest and oldest relative of the very first flowering plant which emerged about 160 million years ago.

 

The uplift took place between 7 and 2.5 million years ago, and as far as I can tell most of the marine fossils were deposited between about 5 and 2.5 million years ago.  The uplifting and changes in sea level were sometimes quite abrupt, leading to distinct boundaries between different epochs of coastline.

The eroded section on this cliff shows where the sea once lapped the shore, and then in a short period the land rose or sea fell by about 15 metres leaving the former shore high and dry.  This formation runs like this for at least 40km along Lifou’s east coast.

 

On Mare the abrupt sea/land level gave rise to this “wedding cake” formation  where 2 former  coast lines can be clearly seen above the present one.

 

In areas where the limestone is weaker and the weathering gentle the preservation can be remarkable, such as this clump of corals and shells which was under a ledge protected from direct rain and sun.  It is hard to believe these are probably around 3-4 million years old.

 

In some places entire corals remain in their original formation, such as this example which about 1m wide and 1.5 m high.

 

In places on the rockshelf  fossils have been naturally polished by the sea.

 

I didn’t have any tools and was not sure if I should be hacking into the rocks so I just collected a couple of items that were lying around, but they give an idea of how much fine detail was preserved.

[Darktooth]

Thank-you very much for sharing these wonderful pictures and information. I really enjoyed reading this. Also I absolutely love those corals!

[FossilGuy1024]

What a fantastic family trip! Thank you for the post.

[Fossildude19]

Nice report and pictures.

Thanks for posting them. 

Regards, 

[Ludwigia]

Fascinating! Thanks for telling us about this little known treasure-trove!

[RJB]

A very interesting post indeed, and what a beautiful location!  Thanks

 

RB

[ynot]

DITTO to what the others have said!

 

Tony

[fossisle]

Cool finds