Hollow tubes

[BirdsAreDinosaurs]

Hi all, 

 

A friend of mine found these in a quarry in Limburg, near Maastricht, many years ago. The exact location is unknown, but it was found in very bright, loose sand (maybe that rings a bell). I suspect they are concretions, but I am not sure. Any info and insights are welcome! Thanks!

 

 

[Rockwood]

I'm going to guess that these date to the late Cretaceous. I think they probably are fossil burrows. Organic matter may aid the concretion of their walls helping to preserve them in this manner. 

[BirdsAreDinosaurs]

Thanks! So I should think of a tube worm of some kind?

[digit]

Probably larger--possibly something like a crustacean.

 

 

Cheers.

 

-Ken