Here along Angola's coast, the bulge lifted the ocean floor hundreds of feet out of the water. Starting about 45,000 years ago, heat flow within Earth's mantle caused the crust to bulge in a process called dynamic uplift. Over millions of years, these sediment layers turned to rock and the remains fossilized - but they were still underwater.

Sediments covered dead animals that sank to the ocean floor. The three-toed tracks of Marala, the 'Emu Man'.This figure shows how Angola's fossils were formed and exposed: 1. The three-toed tracks of Marala, the 'Emu Man'.

“The disappearance of stegosaurs and the apparent drop in diversity of theropods by 115 million years ago suggests that, similar to South America, Australia passed through a period of faunal turnover during the Early Cretaceous Period.”Ī stegosaur track found along the coastline near Walmadany, Western Australia. “The dinosaur fauna from the Broome Sandstone is a lot like what we see in similarly aged faunas from South Africa and South America, and is probably similar to the more globally distributed dinosaur faunas of the Late Jurassic Period. “Both sauropods and ornithopods were diverse and abundant, and stegosaurs and ankylosaurs were the only type of four-legged, bird-hipped dinosaurs. “The results of our study show that the general composition of Australia’s better-known, younger dinosaur fauna was already in place by 127 million to 140 million years ago,” he said. Dr Salisbury said the tracks at Walmadany were considerably older. Most of Australia’s dinosaur fossils come from the eastern side of the continent, and are between 90 million and 115 million years old.

Dr steve dinosaur hunter