110 Million years ago - when dinosaurs walked the earth
About Lightning Ridge
Lightning Ridge is located in northern New South Wales. Around 110 million years ago Lightning Ridge was on the edge of an inland sea called the Eromanga Sea. Fragments of the remains of animals from this time accumulated in the sands of freshwater creeks that drained into the inland sea. Over time these fragments have become opalised. Today, Lightning Ridge deposits contain some of the rarest and most beautiful fossils in the world.
Significant fossils from Lightning Ridge
The most famous and important fossils from Lightning Ridge are those of a special group of mammals that lay eggs, called monotremes. Mammal fossils are rare in Cretaceous fossil deposits, especially in Australia, because the tiny and delicate mammals of this time were far outnumbered by the larger and diverse dinosaurs. This is why these monotreme fossils, which are among the oldest known in the world, are so important. Early monotremes are the ancestors of the modern Platypus and echidnas of Australia and New Guinea. These fossils help us to understand the history of this mysterious group of animals - survivors from the time of the dinosaurs.
Palaeontologists search for fossils in underground opal mines (left) and in rubble processed by mining equipment to remove opal (right).
Photos: © J Brammall & H Godthelp.
Fossils of animals living in the inland sea including fish, lungfish, crocodiles and marine reptiles, such as long-necked plesiosaurs, have also been found at Lightning Ridge. Bones of flying pterosaurs have been found, as have dinosaurs from the time. These include: giant long-necked sauropods; the tiny 1.5m long Lightning Beast Fulgurotherium australe; and large carnivorous predators such as Rapator ornitholestoides that were up to 6m in length.
Fossil-hunting at Lightning Ridge
Palaeontologists searching for fossils of dinosaurs and early kinds of mammals at Lightning Ridge consult with the opal miners who find fossils. Miners often allow the researchers to sift through their spoil heaps or dig in their mines. Without the miners' help, many fossils, including those of Steropodon and Kollikodon, would never have been recognised.
