The Winton Formation is a Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 formation in central-western Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

, Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. The sauropod dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 Austrosaurus

Austrosaurus

Austrosaurus was a sauropod dinosaur from the Allaru Mudstone, from the early Cretaceous of Central-Western Queensland in Australia.-Discovery and species:...

 is found in the early Cretaceous Winton formation.

This formation is a rock unit that blankets large areas of central-western Queensland. It consists of sedimentary rock

Sedimentary rock

Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....

s such as sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

, siltstone

Siltstone

Siltstone is a sedimentary rock which has a grain size in the silt range, finer than sandstone and coarser than claystones.- Description :As its name implies, it is primarily composed of silt sized particles, defined as grains 1/16 - 1/256 mm or 4 to 8 on the Krumbein phi scale...

 and claystone

Claystone

Claystone is a geological term used to describe a clastic sedimentary rock that is composed primarily of clay-sized particles ....

. The sediment

Sediment

Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....

s that make up these rocks represent the remnants of the river plains that filled the basin left by the Eromanga Sea - an inland sea that covered large parts of Queensland and central Australia at least four times during the Early Cretaceous. Great meandering rivers, forest pools and swamps, creeks, lakes and coastal estuaries, all left behind different types of sediment.

In some areas, the Winton Formation is over 400 metres thick. To bring with them such a huge amount of sediment, the rivers that flowed across these plains must have been comparable in size to the present day Amazon

Amazon River

The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...

 or Mississippi

Mississippi River

The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...

 rivers . As more and more sediment was brought in, the margins of the inland sea slowly contracted. By around 95 million years ago, the job was complete and the inland sea would never be seen again.

By virtue of its age and the environmental conditions under which the rocks it consists of were deposited, the Winton Formation represents one of the richest sources of dinosaur fossils anywhere in Australia.

Fauna

A fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 footprint-(ichnite

Ichnite

An ichnite is a fossilised footprint. This is a type of trace fossil. Over the years, many ichnites have been found, around the world, giving important clues about the behaviour of the animals that made them...

), Wintonopus, found with two other dinosaur genera footprints at the Lark Quarry

Lark Quarry

Lark Quarry in Australia is the site of the world's only known record of a dinosaur stampede. Fossilised footprints have been interpreted as a predator stalking and causing a chaotic stampede of around 150 two-legged dinosaurs....

 in Australia, c.f. Tyrannosauropus and Skartopus, have been found in the Winton Formation.

Dinosaur Dinosaur Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of... s of the Winton Formation
Taxa	Presence	Description	Images
Genus: Australovenator Australovenator Australovenator is a genus of allosauroid theropod dinosaur from late Albian -age rocks of Australia... A. wintonensis'	Geographically located in Queensland, Australia.	2 metres (6.6 ft) tall and 6 metres (19.7 ft) long lightweight predatory theropod
Genus: Wintonotitan Wintonotitan Wintonotitan is a genus of titanosauriform dinosaur from late Albian -age rocks of Australia. It is known from partial postcranial remains.-Description and history:... W. wattsi	Geographically located in Queensland, Australia.	Giant herbivorous sauropod about 52 feet (15.8 m) in length.
Genus: Diamantinasaurus Diamantinasaurus Diamantinasaurus is a genus of derived titanosaurian dinosaur from late Albian -age rocks of Australia... D. matildae	Geographically located in Queensland, Australia.	Giant, stocky herbivorous sauropod about 52 feet (15.8 m) in length.
Genus: Austrosaurus Austrosaurus Austrosaurus was a sauropod dinosaur from the Allaru Mudstone, from the early Cretaceous of Central-Western Queensland in Australia.-Discovery and species:... Austrosaurus sp.	Geographically located in Queensland, Australia.
Euornithopoda Tracks.	Geographically located in Queensland, Australia.
Order: Ornithischia Ornithischia Ornithischia or Predentata is an extinct order of beaked, herbivorous dinosaurs. The name ornithischia is derived from the Greek ornitheos meaning 'of a bird' and ischion meaning 'hip joint'... Indeterminate remains.	Geographically located in Queensland, Australia.
Order: Saurischia Saurischia Saurischia meaning 'lizard' and ischion meaning 'hip joint') is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure... Indeterminate remains.	Geographically located in Queensland, Australia.
Infraorder: Sauropoda Sauropoda Sauropoda , or the sauropods , are an infraorder of saurischian dinosaurs. They had long necks, long tails, small heads , and thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land... Undescribed genus. Tracks.	Geographically located in Queensland, Australia. Geographically located in Queensland, Australia.