Blackstone Formation, Australia
{{Short description|Stratigraphic layer in QLD, Australia}}
{{other uses|Blackstone Formation (disambiguation){{!}}Blackstone Formation}}
{{Use dmy dates|date=December 2021}}
{{Use Australian English|date=August 2011}}{{Infobox rockunit
| name = Blackstone Formation
| image =
| caption =
| type = Geological formation
| age = Carnian-Norian
~{{fossil range|235|206}}
| period = Late Triassic
| prilithology = Shale
| otherlithology = Siltstone, coal, tuff
| namedfor = Blackstone, Queensland
| namedby =
| region = Ipswich
| country = {{flag|Australia}}
| coordinates = {{Coord|27.6|S|152.8|E|display=inline,title}}
| paleocoordinates = {{Coord|58.6|S|101.0|E|display=inline}}
| unitof = Ipswich Coal Measures
| subunits = Denmark Hill Insect Bed, Striped Bacon Seam Member
| underlies = Unconformity with Raceview Formation and Aberdare Conglomerate
| overlies = Tivoli Formation
| thickness = {{convert|200|-|240|m|ft|abbr=on}}
| extent =
| area =
| map = {{Location map+ | Australia#Queensland
| relief = 1
| width = 250
| float = center
| places =
{{Location map~ | Australia#Queensland
| lat_deg = -27.6
| lon_deg = 152.8
| mark = Pink ff0080 pog.svg
| marksize = 12
}}
}}
| map_caption =
}}
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
{{see also|Denmark Hill Insect Bed#Fossil content}}
Vertebrates
= Lungfish =
= Invertebrates =
| class="wikitable" align="center" | ||||||
| colspan="7" align="center" | Insects of the Blackstone Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Mesochorista{{cite journal|author=E.F. Riek|year=1955|title=A Re-examination of the Mecopteroid and Orthopteroid Fossils (Insecta) from the Triassic Beds at Denmark Hill, Queensland, with Descriptions of Further Specimens|journal=Australian Journal of Zoology|volume=4|pages=98–110|doi=10.1071/ZO9560098|url=http://insects.tamu.edu/research/neuropterida/neur_bibliography/edocs/riek1956ref6529s-879.pdf|access-date=11 August 2011 }}
| Ipswich | | | A Permochoionid | ||||||
| Mesodiphthera
| M. grandis | | | | rowspan="3" | Tettigarctid cicada | | ||||||
| rowspan="2" | Tardilly
| T. dunstani | | | | | ||||||
| T. prosboloides
| | | | | ||||||
| Phanerogramma
| P. australis | | | | | ||||||
| Dinmopsylla
| D. semota | Dinmore clay pit | | | Archipsyllid Permopsocid | | ||||||
| Mesopsyche
| M. triareolata | Dinmore clay pit | | | |
= Ichnofossils =
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.{{Cite journal|last=Staines|first=H. R. E.|date=1964|title=Recent discovery of Triassic dinosaur footprints in Queensland|journal=Australian Journal of Science|volume=27|pages=55}} 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.{{Cite journal|last=Thulborn|first=T.|date=11 July 2003|title=Comment on "Ascent of Dinosaurs Linked to an Iridium Anomaly at the Triassic-Jurassic Boundary"|url=https://www.science.org/doi/10.1126/science.1082048|journal=Science|language=en|volume=301|issue=5630|pages=169|doi=10.1126/science.1082048|pmid=12855792|s2cid=13247451|issn=0036-8075}} 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.{{Cite journal|last1=Romilio|first1=Anthony|last2=Klein|first2=Hendrik|last3=Jannel|first3=Andréas|last4=Salisbury|first4=Steven W.|date=16 October 2021|title=Saurischian dinosaur tracks from the Upper Triassic of southern Queensland: possible evidence for Australia's earliest sauropodomorph trackmaker|journal=Historical Biology|volume=34 |issue=9 |pages=1834–1843|doi=10.1080/08912963.2021.1984447|s2cid=239170287|issn=0891-2963}} 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
References
{{Reflist}}
= Bibliography =
- {{citation |last=Staines |first=H. R. E. |first2=J. T. |last2=Woods |year=1964 |title=Recent discovery of Triassic dinosaur footprints in Queensland |journal=The Australian Journal of Science |volume=27 |pages=1–55}}
Category:Geologic formations of Australia
Category:Ichnofossiliferous formations