May 4, 2006 — A knucklebone discovered 1.4 miles below the North Sea represents both Norway's first dinosaur find and the world's deepest dino fossil, according to a paper to be published in next month's Norwegian Journal of Geology.

Workmen stumbled upon the fossil while drilling through sandstone for oil exploration at the Snorre offshore field located at the northern end of the North Sea. Jørn Harald Hurum, lead author of the paper, described the bone to Animal Planet News.

"It is a long bone, probably (a) tibia/fibula or radius/ulna," he said. "It is only a small fragment, but it contains a histology only known from Plateosaurus of the same age in Germany (Radial fibro-lamellar bone). So our educated guess (same age and same histology) is Plateosaurus."

Hurum further explained that the fibrous bone tissue located within the knucklebone is unique to Plateosaurus. It is associated with very rapid growth and high rates of bone deposits in the body.

Plateosaurus, which means "flat lizard," had an average length of 29.5 feet and weighed a hefty 8,818.5 pounds. It lived between 222 and 215 million years ago during the Late Triassic and Early Jurassic periods.

A common dinosaur to Europe, Plateosaurus was part of the first group of vegetarian dinos. Its beak-like jaws and leaf-shaped teeth could tear through plant material with ease. The gigantic animal walked on four legs, but many paleontologists think it could rear up on its hind legs so that its clawed forelimbs could reach high branches.

Hurum, who is an assistant professor of vertebrate paleontology at the University of Oslo and a scientist at the university's Natural History Museum, said "the dinosaurs probably roamed in Norway" and he expects that "in the North Sea there should be possibilities to drill through more dinosaurs."

He explained that the sea region consisted of dry plains crossed by large rivers during the dinosaur era. Over time, the landscape compressed to form pockets of fossil alluvial sand that is sandwiched between banks of red shale.

Because of the country's geology, Hurum doubts dinosaur remains will ever be found on the mainland. Norway's youngest rocks are actually twice as old as the dinosaurs.

Daniel Fisher, a paleontologist at the University of Michigan Museum of Paleontology, told Animal Planet News that while the find is "certainly not an everyday occurrence," he was not surprised to learn of the fossil.

"Dinosaur fossils have been found in sedimentary rocks in the deepest sea as well as on the highest mountain ranges," Fisher said. "Subduction (the pushing of Earth's plates against each other) and other geological forces mean that such fossils can exist in these extremely deep or high land and sea environments."

Fisher admitted, "Norway is not known for its dinosaur record."

However, he agreed with Hurum that it is possible dinosaurs once roamed there, although "there" is a relative term when talking about an area over millions of years of time.

"Norway used to be farther south than it is now," Fisher said. "Continental drift could have floated the dinosaur fossil to where it was recently found, but it is likely that dinosaurs and other prehistoric animals once did exist in the general region where Norway is today."