Blackstone Formation, Australia
| Blackstone Formation | |
|---|---|
| Stratigraphic range: Carnian-Norian ~ | |
| Type | Geological formation |
| Unit of | Ipswich Coal Measures |
| Sub-units | Denmark Hill Insect Bed, Striped Bacon Seam Member |
| Underlies | Unconformity with Raceview Formation and Aberdare Conglomerate |
| Overlies | Tivoli Formation |
| Thickness | 200–240 m (660–790 ft) |
| Lithology | |
| Primary | Shale |
| Other | Siltstone, coal, tuff |
| Location | |
| Coordinates | 27°36′S 152°48′E / 27.6°S 152.8°E |
| Approximate paleocoordinates | 58°36′S 101°00′E / 58.6°S 101.0°E |
| Region | Ipswich |
| Country |  Australia |
| Type section | |
| Named for | Blackstone, Queensland |
  Blackstone Formation, Australia (Australia)  Blackstone Formation, Australia (Queensland) | |
The Blackstone Formation is a geologic formation of the Ipswich Coal Measures Group in southeastern Queensland, Australia, dating to the Carnian to Norian stages of the Late Triassic. The shales, siltstones, coal and tuffs were deposited in a lacustrine environment. The Blackstone Formation contains the Denmark Hill Insect Bed.
Fossil content
[edit]Vertebrates
[edit]Lungfish
[edit]| Dipnoans of the Blackstone Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | State | Abundance | Notes | Images | |
| Ceratodus | C. robustus |  | ||||
Invertebrates
[edit]| Insects of the Blackstone Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Mesochorista[1] | M. proavita | Ipswich | A Permochoionid |  | ||
| Mesodiphthera | M. grandis | Tettigarctid cicada | ||||
| Tardilly | T. dunstani | |||||
| T. prosboloides | ||||||
| Phanerogramma | P. australis | Dermapterid earwig | ||||
| Dinmopsylla | D. semota | Dinmore clay pit | Archipsyllid Permopsocid | |||
| Mesopsyche | M. triareolata | Dinmore clay pit | Mesopsychid mecopteran | |||
Ichnofossils
[edit]In 1964, dinosaur footprints were discovered from the Rhondda colliery (underground coal mine) 230 metres below ground along the sandstone ceiling of the Striped Bacon coal seam.[2] These were initially described as Eubrontes, a type of predatory dinosaur (theropod) footprint. Later, these footprints were considered as evidence for the world's largest Triassic theropod, with legs towering over 2 metres tall.[3] A 3D evaluation of the fossil indicated the footprint length was much smaller than previously reported (34 cm rather than 46 cm long) and its shape was characteristic of the trace fossil genus (ichnogenus) Evazoum.[4] The existing hypothesis is that Evazoum were made by prosauropods, ancestral forms of long-necked sauropod dinosaurs. The bipedal dinosaur track-maker may have resembled the dinosaur Plateosaurus, and this fossil is the only evidence of this group of dinosaurs in Australia. The next evidence for sauropodomorphs in Australia comes over 50 million years later in the Jurassic.
See also
[edit]References
[edit]- ^ E.F. Riek (1955). "A Re-examination of the Mecopteroid and Orthopteroid Fossils (Insecta) from the Triassic Beds at Denmark Hill, Queensland, with Descriptions of Further Specimens" (PDF). Australian Journal of Zoology. 4: 98–110. doi:10.1071/ZO9560098. Retrieved 11 August 2011.
- ^ Staines, H. R. E. (1964). "Recent discovery of Triassic dinosaur footprints in Queensland". Australian Journal of Science. 27: 55.
- ^ Thulborn, T. (11 July 2003). "Comment on "Ascent of Dinosaurs Linked to an Iridium Anomaly at the Triassic-Jurassic Boundary"". Science. 301 (5630): 169. doi:10.1126/science.1082048. ISSN 0036-8075. PMID 12855792. S2CID 13247451.
- ^ Romilio, Anthony; Klein, Hendrik; Jannel, Andréas; Salisbury, Steven W. (16 October 2021). "Saurischian dinosaur tracks from the Upper Triassic of southern Queensland: possible evidence for Australia's earliest sauropodomorph trackmaker". Historical Biology. 34 (9): 1834–1843. doi:10.1080/08912963.2021.1984447. ISSN 0891-2963. S2CID 239170287.
Bibliography
[edit]- Staines, H. R. E.; Woods, J. T. (1964), "Recent discovery of Triassic dinosaur footprints in Queensland", The Australian Journal of Science, 27: 1–55