THE world's longest chain of dinosaur footprints would be broken by a new gas processing plant and port planned for the West Australian coast, scientists say.

The fossilised footprints of 15 types of dinosaur, including diplodocus, brachiosaurus, muttaburrasaurus and several types of large carnivore stretch for 80 kilometres along the Kimberley coast around Broome.

Dinosaur

They were made when the dinosaurs strode across mudflats about 130 million years ago, but some of the footprints could be gone forever within a few years if the port goes ahead.

''There's a number of prints here of dinosaurs for which we have no other record in Australia, and some of the sauropod prints are the largest anywhere in the world,'' a University of Queensland palaeontologist, Steve Salisbury, said.