Bulldog Shale

Last updated

Bulldog Shale
Stratigraphic range: Aptian-Albian
~120–110  Ma
Type Geological formation
Unit of Rolling Downs Group
  Marree Subgroup
Sub-unitsWilpoorinna Breccia Member
Underlies Coorikiana Sandstone
Overlies Cadna-owie Formation
Thickness200–340 m (660–1,120 ft)
Lithology
Primary Mudstone, claystone
Other Shale, limestone, gypsum
Location
Coordinates 30°30′S137°12′E / 30.5°S 137.2°E / -30.5; 137.2
Approximate paleocoordinates 67°30′S104°30′E / 67.5°S 104.5°E / -67.5; 104.5
RegionFlag of South Australia.svg  South Australia
CountryFlag of Australia (converted).svg  Australia
Extent Eromanga Basin
Australia relief map.jpg
Green pog.svg
Green pog.svg
Green pog.svg
Green pog.svg
Bulldog Shale (Australia)
Australia South Australia relief location map.png
Green pog.svg
Green pog.svg
Green pog.svg
Green pog.svg
Bulldog Shale (South Australia)

The Bulldog Shale is a formation of Early Cretaceous age (Aptian to Albian stages) that forms part of the Marree Subgroup of the Rolling Downs Group, located in the Eromanga Basin of South Australia, Queensland and New South Wales. [1] [2]

Contents

Description

It is the lowermost unit in the Marree Subgroup, overlying the Cadna-owie Formation and is overlain by the Coorikiana Sandstone. The formation dates to the Aptian to Albian stages of the Early Cretaceous. [3] The Bulldog Shale is composed of finely laminated carbonaceous and pyritic mudstone and claystone beds. Weathering has caused heavy leaching and bleaching in some regions of the Bulldog Shale, including those around Coober Pedy, so that the rocks are white or multicolored. These horizons contain rich opal deposits. Horizons without this bleaching are primarily composed of organic-rich shale. Gypsum, in addition to carbonate limestone concretions rich in fossils are common in these unbleached shaly horizons. [4]

Fossil content

The Bulldog Shale has yielded fossils of plants, invertebrates, fish, and reptiles. [5] The macroinvertebrate fauna of this formation includes several molluscs, such belemnites, gastropods, and bivalves. Fish are represented by chimaeras [6] and ray-finned fish (these include teleosts) [6] and a lungfish. Sharks are conspicuously absent in the Bulldog Shale. [4] Many plesiosaurs are known from the formation, including leptocleidids, elasmosaurids, [4] pliosaurids, and possible polycotylids. Ichthyosaurs are also present. [7] Archosaur fossils from the Bulldog Shale are rare, and are represented mostly indeterminate specimens, some of which can be assigned to Dinosauria. [8] Due to the coastal location of the Bulldog Shale, large amounts of wood have also been recovered in this formation. [4]

Paleobiota

Archosaurs

Archosaurs reported from the Bulldog Shale
GenusSpeciesLocationMaterialNotesImages
Archosauria Indet.Andamooka, Coober PedyVarious fragments, some opalizedIncludes some material referable to Dinosauria (Theropoda) [8]
Kakuru K. kujaniAndamookaOpalized tibiaNow considered Tetanurae indet. [8]

Plesiosaurs

Plesiosaurs reported from the Bulldog Shale
GenusSpeciesLocationMaterialNotesImages
Kronosaurus K. queenslandicusTeethOriginally referred to cf. K. sp. [4] [7]
Kronosaurus.jpg
Leptocleidus L. sp.Reclassified as Umoonasaurus [7]
Opallionectes O. andamookaensisLunatic Hill opal fieldOpalized incomplete articulated skeletonA plesiosaur of uncertain classification [4] [7]
Umoonasaurus U. demoscyllusZorba Extension Opal Field, Andamooka opal fields, Curdimurka area, Neales River regionOpalized skulls and skeletonsA small leptocleidid [9] plesiosaur with three crests on its head [2]
Umoonasaurus demoscyllus.png
Elasmosauridae Indet.AndamookaPartial skeletons and several fragments [4]
Polycotylidae Indet.Hermit HillFragmentary specimen [4]

Ichthyosaurs

Ichthyosaurs reported from the Bulldog Shale
GenusSpeciesLocationMaterialNotesImages
Platypterygius P. sp.Bopeechee SidingFragmentary cranial and postcranial materialThe specimen SAM P14508 shows evidence of healed bite marks. [5]
Platypterigius longmani DB.jpg

Chondrichthyes

Chondrichthyans reported from the Bulldog Shale
GenusSpeciesLocationMaterialNotesImages
Ptyktoptychion P. eyrensisNear Lake Eyre in northern South Australia [10] [11]

Invertebrates

Invertebratess reported from the Bulldog Shale
GenusSpeciesLocationMaterialNotesImages
Isocrinus I. australis Opalised calyx [12]
Maccoyella M. barklyi [13]
Pursiphonia P. clarkei Opalised sponge remains [12]
Tropaeum T. imperator [13]
Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

See also

Related Research Articles

<span class="mw-page-title-main">South Polar region of the Cretaceous</span> Animals that lived below the Antarctic circle in the Cretaceous

The South Polar region of the Cretaceous comprised the continent of East Gondwana–modern day Australia, Zealandia, and Antarctica–a product of the break-up of Gondwana in the Cretaceous Period. The southern region, during this time, was much warmer than it is today, ranging from perhaps 4–8 °C (39–46 °F) in the latest Cretaceous Maastrichtian in what is now southeastern Australia. This prevented permanent ice sheets from developing and fostered polar forests, which were largely dominated by conifers, cycads, and ferns, and relied on a temperate climate and heavy rainfall. Major fossil-bearing geological formations that record this area are: the Santa Marta and Sobral Formations of Seymour Island off the Antarctic Peninsula; the Snow Hill Island, Lopez de Bertodano, and the Hidden Lake Formations on James Ross Island also off the Antarctic Peninsula; and the Eumeralla and Wonthaggi Formations in Australia.

<i>Kronosaurus</i> Pliosaur genus from the Early Cretaceous period

Kronosaurus is an extinct genus of short-necked pliosaurs that lived during the Early Cretaceous period in what is now Australia. It is a monotypic genus with one species K. queenslandicus, described in 1924 from the Toolebuc Formation in Queensland, Australia. With traditionally attributed fossils indicating a total length of up to 10 meters (33 ft), Kronosaurus may have been among the largest pliosaurs.

<i>Koolasuchus</i> Extinct genus of amphibians

Koolasuchus is an extinct genus of brachyopoid temnospondyl in the family Chigutisauridae. Fossils have been found from Victoria, Australia and date back 125-120 million years ago to Barremian-Aptian stages of the Early Cretaceous. Koolasuchus is the youngest known temnospondyl. It is known from several fragments of the skull and other bones such as vertebrae, ribs, and pectoral elements. The type species Koolasuchus cleelandi was named in 1997. K. cleelandi was adopted as the fossil emblem for the state of Victoria, Australia on 13 January 2022.

<i>Kakuru</i> Extinct genus of theropod dinosaurs

Kakuru is a dubious genus of theropod dinosaur from the early Cretaceous Period.

<i>Umoonasaurus</i> Extinct species of reptile

Umoonasaurus is an extinct genus of plesiosaur belonging to the family Leptocleididae. This genus lived approximately 115 million years ago during the Early Cretaceous period, in shallow seas covering parts of what is now Australia. It was a relatively small animal around 2.5 metres (8.2 ft) long. An identifying trait of Umoonasaurus is three crest-ridges on its skull.

Opallionectes andamookaensis is the name given to a 5 m (16 ft) long cryptoclidian plesiosaur, which is thought to have lived during the early Cretaceous period, 115 million years ago, in shallow seas covering what is now Australia.

The Eromanga Basin is a large Mesozoic sedimentary basin in central and northern Australia. It covers parts of Queensland, the Northern Territory, South Australia, and New South Wales, and is a major component of the Great Artesian Basin. The Eromanga Basin covers 1,000,000 km2 and overlaps part of the Cooper Basin.

The Toolebuc Formation is a geological formation that extends from Queensland across South Australia and the Northern Territory in Australia, whose strata date back to the Albian stage of the Early Cretaceous. Dinosaurs, pterosaurs, plesiosaurs, ichthyosaurs, protostegid turtles, sharks, chimaeroids and bony fish remains are among the fossils that have been recovered from the formation.

The Allaru Formation, also known as the Allaru Mudstone, is a geological formation in Queensland, Australia, whose strata date back to the Early Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.

The Marree Subgroup, previously described as Maree Formation and Marree Formation, is a geological subgroup in the Eromanga Basin of South Australia whose strata date back to the Aptian. The subgroup was first described as a formation by Forbes in 1966. Dinosaur remains are among the fossils that have been recovered from the formation.

The Griman Creek Formation is a geological formation in northern New South Wales and southern Queensland, Australia whose strata date back to the Albian-Cenomanian stages of the mid-Cretaceous. It is most notable being a major source of opal, found near the town of Lightning Ridge, New South Wales. Alongside the opal opalised fossils are also found, including those of dinosaurs and primitive monotremes.

<span class="mw-page-title-main">Wonthaggi Formation</span>

The Wonthaggi Formation is an informal geological formation in Victoria, Australia whose strata date back to the Early Cretaceous. It is part of the Strzelecki Group within the Gippsland Basin. Dinosaur remains are among the fossils that have been recovered from the formation. It is partially equivalent to the Eumeralla Formation.

<span class="mw-page-title-main">Eumeralla Formation</span> Geological formation in Victoria, Australia

The Eumeralla Formation is a geological formation in Victoria, Australia whose strata date back to the Early Cretaceous. It is Aptian to Albian in age. Dinosaur remains are among the fossils that have been recovered from the formation, particularly from the Dinosaur Cove locality.

Eromangasaurus is an extinct genus of elasmosaurid known from northern Queensland of Australia.

The Wallumbilla Formation is an Aptian geologic formation found in Australia. Plesiosaur and theropod remains are among the fossils that have been recovered from its strata.

<span class="mw-page-title-main">Paja Formation</span> Early Cretaceous geologic formation of central Colombia

The Paja Formation is an Early Cretaceous geologic formation of central Colombia. The formation extends across the northern part of the Altiplano Cundiboyacense, the Western Colombian emerald belt and surrounding areas of the Eastern Ranges of the Colombian Andes. In the subsurface, the formation is found in the Middle Magdalena Valley to the west. The Paja Formation stretches across four departments, from north to south the southernmost Bolívar Department, in Santander, Boyacá and the northern part of Cundinamarca. Well known fossiliferous outcrops of the formation occur near Villa de Leyva, also written as Villa de Leiva, and neighboring Sáchica.

<span class="mw-page-title-main">Australian Age of Dinosaurs</span> Museum of Natural History in Winton, Queensland

Australian Age of Dinosaurs Ltd. (AAOD) is a nonprofit organization located in Winton, Queensland, founded by David Elliott and Judy Elliott in 2002. The organization’s activities include the operation of the Australian Age of Dinosaurs Museum of Natural History, which holds annual dinosaur digs in the Winton Formation of Western Queensland and oversees the year-round operation of Australia's most productive dinosaur fossil preparation laboratory. Since 2005, the AAOD Museum has accumulated the largest collection of Australian dinosaur fossils in the world and holds the holotype specimens of Diamantinasaurus matildae ("Matilda"), Savannasaurus elliottorum ("Wade"), Australovenator wintonensis ("Banjo"), Australia's most complete theropod skeleton, Ferrodraco lentoni, the first pterosaur to be named from the Winton Formation, and Confractosuchus sauroktonos. The museum is open to the public daily from April to October and is open six days a week from November to March. The site of the museum was designated a dark-sky preserve, the first International Dark-Sky Sanctuary in Australia, in 2019.

<span class="mw-page-title-main">Araripe Basin</span> Rift Basin in brazil famous for its pterosaur fossils

The Araripe Basin is a rift basin covering about 8,000 square kilometres (3,100 sq mi), in Ceará, Piauí and Pernambuco states of northeastern Brazil. It is bounded by the Patos and Pernambuco lineaments, and is situated east of the Parnaíba Basin, southwest of the Rio do Peixe Basin and northwest of the Tucano and Jatobá Basins.

<i>Leyvachelys</i> Extinct genus of turtles

Leyvachelys is an extinct genus of turtles in the family Sandownidae from the Early Cretaceous of the present-day Altiplano Cundiboyacense, Eastern Ranges, Colombian Andes. The genus is known only from its type species, Leyvachelys cipadi, described in 2015 by Colombian paleontologist Edwin Cadena. Fossils of Leyvachelys have been found in the fossiliferous Paja Formation, close to Villa de Leyva, Boyacá, after which the genus is named. The holotype specimen is the oldest and most complete sandownid turtle found to date.

<span class="mw-page-title-main">Santana Group</span>

The Santana Group is a geologic group, formerly included as the middle part of the Araripe Group, in the Araripe Basin of northeastern Brazil. The group comprises the Crato, Ipubi and Romualdo Formations and is dated to the Aptian to Albian stages of the Early Cretaceous. The formations of the group were deposited in a lacustrine to subtidal shallow marine environment in the Araripe rift basin.

References

  1. Geoscience Australia. "Stratigraphic Unit Details: Bulldog Shale". Australian Stratigraphic Units Database. Retrieved 26 June 2020.
  2. 1 2 Kear, Benjamin P.; Schroeder, Natalie I.; Lee, Michael S.Y. (2006). "An archaic crested plesiosaur in opal from the Lower Cretaceous high-latitude deposits of Australia". Biology Letters. 2 (4): 615–619. doi:10.1098/rsbl.2006.0504. PMC   1833998 . PMID   17148303.
  3. Bulldog Shale at Fossilworks.org
  4. 1 2 3 4 5 6 7 8 Kear, Benjamin P. (2006). "Marine reptiles from the Lower Cretaceous of South Australia: elements of a high‐latitude cold‐water assemblage". Palaeontology. 49 (4): 837–856. Bibcode:2006Palgy..49..837K. doi: 10.1111/j.1475-4983.2006.00569.x . S2CID   128232205.
  5. 1 2 Zammit, Maria; Kear, Benjamin P. (2011). "Healed bite marks on a Cretaceous ichthyosaur" (PDF). Acta Palaeontologica Polonica. 56 (4): 859–863. doi: 10.4202/app.2010.0117 .
  6. 1 2 McHenry, Colin R. (2009). Devourer of Gods: The palaeoecology of the Cretaceous pliosaur Kronosaurus queenslandicus (Thesis). The University of Newcastle.
  7. 1 2 3 4 Kear, Benjamin P. (2016). "Cretaceous marine amniotes of Australia: perspectives on a decade of new research" (PDF). Memoirs of Museum Victoria. 74: 17–28. doi: 10.24199/j.mmv.2016.74.03 .
  8. 1 2 3 Barrett, Paul M.; Kear, Benjamin P.; Benson, Roger B.J. (2010). "Opalized archosaur remains from the Bulldog Shale (Aptian: Lower Cretaceous) of South Australia" (PDF). Alcheringa. 34: 1–9. ISSN   0311-5518.
  9. Parrilla-Bel, Jara; Canudo, José Ignacio (2015). "On the presence of plesiosaurs in the Blesa Formation (Barremian) in Teruel (Spain)". Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 278 (2): 213–227. doi:10.1127/njgpa/2015/0526.
  10. Kear, Benjamin P. (2011). Dinosaurs in Australia : Mesozoic life from the Southern Continent. Robert J. Hamilton-Bruce, CSIRO Publishing. Collingwood, Vic.: CSIRO Pub. p. 86. ISBN   978-0-643-10169-2. OCLC   692219338.
  11. Popov, Evgeny V. (2020-12-10). "Systematic reassessment of Edaphodon eyrensis Long, 1985 (Holocephali, Chimaeroidei) from the Early Cretaceous of South Australia". Journal of Vertebrate Paleontology. 40 (6): e1884564. doi:10.1080/02724634.2020.1884564. ISSN   0272-4634.
  12. 1 2 Kear, Benjamin P. (2011). Dinosaurs in Australia : Mesozoic life from the Southern Continent. Robert J. Hamilton-Bruce, CSIRO Publishing. Collingwood, Vic.: CSIRO Pub. p. 82. ISBN   978-0-643-10169-2. OCLC   692219338.
  13. 1 2 Kear, Benjamin P. (2011). Dinosaurs in Australia : Mesozoic life from the Southern Continent. Robert J. Hamilton-Bruce, CSIRO Publishing. Collingwood, Vic.: CSIRO Pub. p. 83. ISBN   978-0-643-10169-2. OCLC   692219338.

Further reading