| Winton Formation | |
| Type: | Geological formation |
| Age: | Late Albian-Early Turonian ~ |
| Period: | Turonian |
| Prilithology: | Sandstone, siltstone, claystone |
| Otherlithology: | Conglomerate, coal |
| Country: |  Australia |
| Coordinates: | -22.3°N 143.1°W |
| Paleocoordinates: | -51.8°N 134.1°W |
| Unitof: | Rolling Downs Group |
| Underlies: | Unconformity with Quaternary Lake Eyre Basin sediments |
| Overlies: | Mackunda Formation,[1] Oodndatta Formation |
| Thickness: | <100m (300feet) at the margin 1200m (3,900feet) in the centre |
| Extent: | Eromanga Basin |
| Map: | Winton formation.svg |
| Namedfor: | Winton, Queensland |
| Namedby: | Whitehouse |
| Year Ts: | 1955 |
| Location Ts: | Bores in and around Winton |
The Winton Formation is a Cretaceous geological formation in central-western Queensland, Australia. It is late Albian to early Turonian in age.[2] The formation blankets large areas of central-western Queensland. It consists of sedimentary rocks such as sandstone, siltstone and claystone. The sediments 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 or Mississippi rivers. As more and more sediment was brought in, the margins of the inland sea slowly contracted. By around 95 million years ago, the deposition 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.
A fossil footprint-(ichnite), Wintonopus, found with two other dinosaur genera footprints at the Lark Quarry in Australia, c.f. Tyrannosauropus and Skartopus, have been found in the Winton Formation.
| Dipnoi of the Winton Formation | |||||
|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images |
| Metaceratodus[3] | M. bonei | Isolated tooth plates | Lungfish belonging to the extinct family Ceratodontidae | ||
| M. ellioti | |||||
| M. wollastoni | |||||
| Crocodyliformes of the Winton Formation | |||||
|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images |
| Confractosuchus[7] | C. sauroktonos | Nearly complete skeleton preserving a juvenile ornithopod in its abdomen | |||
| Isisfordia | I. duncani | Nearly complete skeleton and partial skull, referred complete skull | |||
| Ornithischians of the Winton Formation | ||||||
|---|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images | |
| Amblydactylus | A. gethingi | Lark Quarry. | Multiple footprints. | |||
| Ankylosauria[8] | Indeterminate | Three isolated teeth from left and right dentary and right maxilla | ||||
| Neornithischia | Indeterminate | Tooth[9] | ||||
| Ornithopoda | Indeterminate | Digested remains associated with the holotype of Confractosuchus | ||||
| Ornithopoda | Undescribed | A nearly complete skull and mandible and at least three partial postcranial skeletons.[10] | Small-bodied, recovered as part of "Elasmaria" | |||
| Wintonopus | W. latomorum | Snake Creek and Lark Quarry track site. | Footprints. | An ornithopod. | ||
| Sauropods of the Winton Formation | ||||||
|---|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images | |
| Australotitan[11] | A. cooperensis | A partial scapula, humeri, ulna, pubes, ischia, femora, presacral vertebral centrum fragments, and rib fragments. | A large diamantinasaurian sauropod that possesses a mosaic of features shared with titanosaurians with similar geographical and temporal range. Possibly a junior synonym of Diamantinasaurus.[12] | |||
| Diamantinasaurus | D. matildae | A squamosal, quadrates, braincase, surangular, atlas intercentrum axis, cervical vertebrae, middle cervical neural arch, co-ossified sacral centra, cervical ribs, dorsal vertebrae, numerous dorsal ribs, fragmentary gastralia, coalesced sacral vertebrae, isolated sacral processes, scapula, coracoid, partial sternal plate, humeri, ulnae, radius, metacarpals I–V, manual phalanges, ilium, pubes, both ischia, femur, tibia, fibula, astragalus, and numerous fragments. | A diamantinasaurian sauropod known from partial cranial material. | |||
| Savannasaurus[13] | S. elliottorum | Posterior cervical vertebrae, cervical ribs, dorsal vertebrae, dorsal ribs, sacral vertebrae with processes, partial caudal vertebrae, fragmentary scapula, coracoid, sternal plates, incomplete humeri, shattered ulna, radius, metacarpals I–V, metacarpal IV, manual phalanges, fragments of ilia, pubes, ischia, astragalus, metatarsal III, and associated fragments. | A wide-bodied sauropod that was well adapted to the wet, temperate floodplain environment it inhabited. | |||
| Sauropoda | Indeterminate | Poorly preserved remains associated with the holotype of Confractosuchus | ||||
| Titanosauriformes | Undescribed | Partial skull, consisting of a braincase, quadrates, quadratojugals, a left squamosal, postorbitals, and several unprepared elements. associated with a hind limb[14] | ||||
| Wintonotitan | W. wattsi | A scapula, both humeri, both ulnae, both radii, near complete metacarpus preserving complete metacarpals II–V with proximal half of metacarpal I, fragmentary dorsal and sacral vertebrae and ribs, partial ilium, ischium, caudal vertebral series including anterior caudals, middle caudals, posterior caudals, proximal chevrons, and numerous unidentifiable fragments. | A titanosaur that is likely to be closely related to Australotitan, Diamantinasaurus and Savannasaurus. | |||
| Theropods of the Winton Formation | |||||
|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images |
| Australovenator[15] | A. wintonensis | Dentaries, dorsal ribs and rib fragments, gastralial ribs and fragments, partial ilium, ulnae, radius, manus metacarpals, unguals, femur, tibiae, fibula, astragalus, metatarsals, pedal phalanges, humeri, radiale, distal carpal, and manual phalanxes. | A megaraptoran theropod known from postcranial and cranial material. | ||
| Megaraptoridae[16] | Indeterminate | A partial skeleton, consisting of caudal vertebrae, metatarsals, a phalanx, and numerous unidentifiable fragments. | |||
| Flora of the Winton Formation[18] | |||||
|---|---|---|---|---|---|
| Taxa | Species | Presence | Material | Notes | Images |
| Angiospermae | Indeterminate | Leaf impressions, cuticle fragments | At least ten distinct types, belonging to both monocots and dicotyledons | ||
| Araucariaceae | Indeterminate | Leaves | |||
| Austrosequoia | A. wintonensis | Cones and leaved axes | A member of Cupressaceae | ||
| Cheirolepidiaceae | Four taxa | Dispersed cuticle | |||
| Emwadea | E. microcarpa | Seed cones | A member of Araucariaceae, more closely related to Agathis and Wollemia than Araucaria.[19] | ||
| Equisetites | Indeterminate | Axes | Horsetail | ||
| Ginkgo | G. wintonensis, four other possible species | Leaf impressions (G. wintonensis) Dispersed cuticle | A gingophyte, genus extant. | ||
| Lovellea | L. wintonensis | Permineralised flower | A member of Laurales | ||
| Aff. Lygodium? | Indeterminate | Fern pinna | |||
| Marchantites | M. marguerita | Liverwort | |||
| Microphyllopteris | cf. M. gleichenoides | Frond fragment impression | A fern belonging to the family Gleicheniaceae | ||
| Otozamites | cf. O. bengalensis | Leaves | Member of Bennettitales | ||
| Phyllopteroides | P. macclymontae | Numerous pinnule impressions | A fern belonging to the family Osmundaceae | ||
| Pterostoma | Indeterminate | Leaves | A possible cycad | ||
| Ptilophyllum | Indeterminate | Leaves | Member of Bennettitales | ||
| Taeniopteris | Indeterminate | Leaf impression | A member of Pentoxylales, youngest record of the group in Australia | ||
| Tempskya | T. judithae | Permineralized false trunks | A tree fern | ||