There’s a new episode of PBS Eons.  This one is about an amazing specimen of Nodosaur discovered in Canada in 2011.  It was found in a siderite concretion which formed in the ocean.

Paleontologists have been studying nodosaurs since the 1830s, but nobody had ever found a specimen like Borealopelta before. The key to its exceptional preservation was where it ended up after it died and how it got there.