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Precipice Sandstone

Coordinates: 24°18′S 150°30′E / 24.3°S 150.5°E / -24.3; 150.5
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(Redirected from Razorback Beds)

Precipice Sandstone
Stratigraphic range: Sinemurian to early Pliensbachian
~199–187 Ma
Mount Morgan Mine, where strata of the formation was exposed
TypeGeological formation
Unit ofBundamba Group
Sub-units
  • Lower Member
  • Upper Member
UnderliesEvergreen Formation
Overlies
Thickness175 m (574 ft)
Lithology
PrimarySandstone
OtherSiltstone, mudstone
Location
Coordinates24°18′S 150°30′E / 24.3°S 150.5°E / -24.3; 150.5
Approximate paleocoordinates58°36′S 92°24′E / 58.6°S 92.4°E / -58.6; 92.4
Region Queensland
 New South Wales
Country Australia
ExtentSurat Basin
Type section
Named forSandstone cliffs in the gorge of Precipice Creek, a tributary of the Dawson River
Named byWhitehouse
Precipice Sandstone is located in Australia
Precipice Sandstone
Precipice Sandstone (Australia)

The Precipice Sandstone an Early Jurassic (Sinemurian to early Pliensbachian, with possible Hettangian levels) geologic formation of the Surat Basin in New South Wales and Queensland, eastern Australia, know due to the presence of abundant vertebrate remains & tracks.[1][2][3] This unit includes the previously described Razorback beds.[4] This unit represents a major, almost primary, source of hydrocarbons in the region, with a Potential CO2 reservoir of up to 70m.[5] It was deposited on top of older sediments, like Bowen Basin units, in an unconformable manner, resting along the eastern basin margin and the Back Creek Group in the southern Comet Platform, while in other areas it directly overlies the Triassic Moolayember Formation & Callide Coal Measures, being deposited in a comparatively stable basin.[3] Isopach maps of the Precipice Sandstone indicate two distinct areas of sediment accumulation, suggesting two separate depocentres filled from different source regions during the Sinemurian, with the Thomson orogeny and New England Orogen hinterlands as possible ones.[6] This unit represented a fluvial-palustrine-lacustrine braided channel north-flowing succession, that seem to have debouch into a shallow restricted tidal/wave influenced marine embayment, marked at areas like Woleebee Creek.[7] Paleoenvironment-wise, it represents a hinterland rich in vegetation, hinting at wet environments like swamps, where agglutinated foraminifera suggests marine flooding and drier conditions or the encroachment of seawater onto coastal areas.[8]

Fireclay Caverns

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Fireclay Caverns' Site A1 trackmaker (Mount Morgan, Queensland) placed in its footprints to scale with a 1.75 m tall human.

The Fireclay Caverns were excavated by the Mount Morgan Mine to provide clay for its brickworks resulting in very large openings that measure between 4–12 metres in height from the cave floor.[9] Excavation of the caverns ceased when the mine brickworks were decommissioned in the early 1900s.[10] Erosion revealed dinosaur footprints (preserved as infills) being discovered in 1954.[10] To date, nine different ceiling sections of the Fireclay Caverns have been recognised as containing dinosaur footprints. These have been dated to the Early Jurassic (Sinemurian) ~195 million years ago.[9] Walkways and stairs had been constructed in 2010 to provide access to the dinosaur footprints [11] as part of the mine site tours. The site was closed to access in 2011 due to ceiling erosion posing a significant risk to public safety.[9]

The Fireclay Caverns were excavated to supply clay to brickworks of the Mount Morgan Mine. Clay was mined from within the caverns by pick and shovel, then transferred by underground rail to a brickworks lower in the Mount Morgan Mine site. Excavation from the caverns ceased when their clay was no longer required by the mine. After cavern excavations ceased, clay progressively fell from the cavern ceilings, revealing rock ceilings above. In 1954, HRE Staines, a Mount Morgan Limited geologist, identified dinosaur footprints in the rock ceilings.[10][12] Over 300 such footprints have been identified on the cavern ceilings dated to the Early Jurassic (Sinemurian) ~195 million years ago.[13][14] 2024 represents the 70th anniversary of when Ross Staines published Australia's first dinosaur trackway-consisting of four footprints.[10][14] To celebrate, previously unpublished archival photographs (c. 1954) enabled a re-examination of Staines' original trackway, from which two additional footprints were revealed.[15] Analyses indicated the trackmaker exhibited a walking gait, initially walking at ~3.8 km/h and then slowed to 1.8 km/h in association with a slight turn in direction.[15]

After cavern excavations ceased, a colony of bent-wing bats began inhabiting the caverns. The sections of the caverns containing the bats are inaccessible to protect the bat habitat.

Biota

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Invertebrates

[edit]
Genus Species Type Location Material Origin Notes Images
Asterosoma[16]
  • A. isp.
Fodinichnia
  • Chinchilla 4 Borehole
  • Condabri MB9-H Borehole
  • Kenya East GW7 Borehole
  • Moonie 31 Borehole
  • Moonie 34 Borehole
  • Reedy Creek MB3-H Borehole
  • Roma 8 Borehole
  • Taroom 17 Borehole
  • West Wandoan 1 Borehole
  • Woleebee Creek GW4 Borehole
Radiating bulb-like swelling burrows Annelid worm, vermiform organism Freshwater/Blackish burrow-like ichnofossils
Conichnus[16]
  • C. isp.
  • Domichnia
  • Cubichnia
trails Gastropods Freshwater/Blackish fillings-like ichnofossils
Cylindrichnus[16]
  • C. isp.
  • Domichnia
Long, subconical, weakly curved burrows
  • Anemones
  • Polychaete worms
Freshwater/Blackish burrow-like ichnofossils
Diplocraterion[16]
  • D. parallelum
Domichnia U-shaped burrows Marine-Mangroove Vertical, U-shaped, single-spreite Burrows; unidirectional or bidirectional spreite, generally continuous, rarely discontinuous. Most Diplocraterion show only protrusive spreiten, like the local ones, produced under predominantly erosive conditions where the organism was constantly burrowing deeper into the substrate as sediment was eroded from the top.
Diplocraterion parallelum diagram
Helminthopsis[16]
  • H. isp.
Fodinichnia Simple, unbranched, horizontal cylinder traces Saltwater/Blackish burrow-like ichnofossils.
Example of Helminthopsis fossil
Lockeia[16]
  • L. amygdaloides
  • L. isp.
  • Cubichnia
  • Domichnia
Dwelling traces
  • Bivalves
Marine, brackish or freshwater resting traces of Bivalves.
Naktodemasis[16]
  • N. isp.
Fodinichnia Straight to sinuous, unlined and unbranched burrows
  • Soil bugs
  • Cicada nymphs
  • Scarabaeid beetle larvae
Freshwater/Terrestrial burrow-like ichnofossils.
Palaeophycus[16]
  • P. tubularis
Domichnia Straight or gently curved tubular burrows.
  • Polychaetes
  • Semiaquatic Insects (Orthoptera and Hemiptera)
  • Semiaquatic and non-aquatic Beetles.
Freshwater/Blackish burrow-like ichnofossils.
Example of Palaeophycus fossil
Phycosiphon[16]
  • P. isp.
Fodinichnia Irregularly meandering burrows Vermiform Animals Freshwater burrow-like ichnofossils.
Planolites[16]
  • P. montanus
  • P. beverleyensis
  • P. isp.
Pascichnia Cylindrical or elliptical curved/tortuous trace fossils
  • Polychaetes
  • Insects
Freshwater/Blackish burrow-like ichnofossils. Planolites is really common in all types of the Ciechocinek Formation deposits. It is referred to vermiform deposit-feeders, mainly Polychaetes, producing active Fodinichnia. It is controversial, since is considered a strictly a junior synonym of Palaeophycus.
Example of Planolites fossil
Scolicia[16]
  • S. isp.
  • Cubichnia
Symmetrical trail or burrow Gastropods Freshwater/Blackish trail-like ichnofossils
Scolicia trails
Skolithos[16]
  • S. isp.
Domichnia Cylindrical strands with branches
  • Polychaetes
  • Phoronidans
Blackish trace ichnofossils. Interpreted as dwelling structures of vermiform animals, more concretely the Domichnion of a suspension-feeding Worm or Phoronidan.
Siphonichnus[16]
  • S. ophthalmoides
Domichnia Cylindrical strands with branches
  • Polychaetes
  • Phoronidans
Blackish trace ichnofossils. Interpreted as dwelling structures of vermiform animals, more concretely the Domichnion of a suspension-feeding Worm or Phoronidan.
Taenidium[16]
  • T. serpentinum
  • T. isp.
Fodinichnia Unlined meniscate burrows Freshwater/Blackish burrow-like ichnofossils. Taenidium is a meniscate backfill structure, usually considered to be produced by an animal progressing axially through the sediment and depositing alternating packets of differently constituted sediment behind it as it moves forward.
Thalassinoides[16]
  • T. isp.
Tubular Fodinichnia Tubular Burrows Burrow-like ichnofossils. Large burrow-systems consisting of smooth-walled, essentially cylindrical components. Common sedimentary features are Thalassinoides trace fossils in the fissile marlstone to claystone intervals
Thalassinoides burrowing structures, with modern related fauna, showing the ecological convergence and the variety of animals that left this Ichnogenus.
Teichichnus[16]
  • T. isp.
Fodinichnia Vertical to oblique, unbranched or branched, elongated to arcuate spreite burrow Saltwater/Blackish burrow-like ichnofossils. The overall morphology and details of the burrows, in comparison with modern analogues and neoichnological experiments, suggest Echiurans (spoon worms) or Holothurians (sea cucumbers) with a combined suspension- and deposit-feeding behaviour as potential producers.
Teichichnus burrows

Vertebrata

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Genus Species Location Stratigraphic position Material Notes Images

Anomoepodidae[17]

Indeterminate

  • Biloela

Lower Member

Footprints

ornithischian footprints, unassigned to any concrete ichnogenus, but with resemblance with Anomoepodidae

Small ornithischians similar to Lesothosaurus may have left these footprints

Anomoepus[15][18]

  • A. scambus
  • A. ispp.
  • Carnarvon Gorge
  • Fireclay Caverns
  • Mount Morgan

Lower Member

Footprints

Ornithischian Footprints, originally suggested as quadrupedal theropod tracks, latter identified as of Ornithischian origin.[19] Up to 130 tracks & 4 short trackways are know.

Eubrontes[20]

E. isp.

Fireclay Caverns

Lower Member

Footprints

Medium-sized Theropod Footprints. Currently represent the largest of the prints at Mount Morgan

Grallator[20]

G. isp.

Fireclay Caverns

Lower Member

Footprints

Small-sized Theropod Footprints

Plesiosauria[21]

Indeterminate

  • Mount Morgan

Razorback Beds

  • QM F3983-QM F5500, single disarticulated skeleton preserved as natural moulds

A Freshwater Plesiosaur that cannot be confidently attributed to any particular plesiosaurian clade

Theropodipedia[1][22]

Indeterminate

  • Callide Mine
  • Mount Morgan

Lower Member

Footprints

Possible theropod footprints, unassigned to any concrete ichnogenus. One morphotype includes large tridactyl prints, up to 24 cm.

Small theropods similar to Procompsognathus may have left these footprints

"Indet. 2"[9]

Fireclay Caverns

"Indet. 3"[9]

Fireclay Caverns

Wintonopus[20]

W. isp.

Fireclay Caverns

Lower Member

Footprints

Small-sized Ornithischian Footprints

Bryophyta

[edit]
Genus Species Stratigraphic position Material Notes Images

Annulispora[23]

  • A. folliculosa
  • A. microannulata
  • Razorback Beds
  • Spores

Incertae sedis; affinities with Bryophyta.

Cingutriletes[23]

  • C. spp.

Incertae sedis; affinities with Bryophyta.

Distalanulisporites[23]

  • D. punctus
  • D. verrucosus

Affinities with the family Sphagnaceae in the Sphagnopsida.

Foraminisporis[23]

  • F. spp.

Affinities with the family Notothyladaceae in the Anthocerotopsida.

Nevesisporites[23]

  • N. vallatus

Incertae sedis; affinities with Bryophyta. This spore is found in Jurassic sediments associated with the polar regions.

Polycingulatisporites[23]

  • P. crenulatus
  • P. densatus
  • P. mooniensis

Affinities with the family Notothyladaceae in the Anthocerotopsida. Hornwort spores.

Extant Notothylas specimens

Stereisporites[23]

  • S. antiquasporites
  • S. perforatus

Affinities with the family Sphagnaceae in the Sphagnopsida. "Peat moss" spores, related to genera such as Sphagnum that can store large amounts of water.

Extant Sphagnum specimens

Lycophyta

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Genus Species Stratigraphic position Material Notes Images

Apiculatisporis[23]

  • A. spp.
  • Razorback Beds
  • Spores

Incertae sedis; affinities with Lycopodiopsida

Lycopodiumsporites[23]

  • L. austroclavatidites
  • L. rosewoodensis

Affinities with the family Lycopodiaceae in the Lycopodiopsida. Lycopod spores, related to herbaceous to arbustive flora common in humid environments.

Extant Lycopodium specimens

Neoraistrickia[23]

  • N. truncata
  • N. spp.

Affinities with the Selaginellaceae in the Lycopsida.

Pteridophyta

[edit]
Genus Species Stratigraphic position Material Notes Images

Calamospora[23]

  • C. spp.
  • Razorback Beds
  • Spores

Affinities with the Calamitaceae in the Equisetales. Horsetails are herbaceous flora found in humid environments and are flooding-tolerant. In the sections of the formation such as Korsodde, this genus has small peaks in abundance in the layers where more Equisetites stems are found.

Reconstruction of the genus Calamites, found associated with Calamospora

Pteridophyta

[edit]
Genus Species Stratigraphic position Material Notes Images

Annulispora[23]

  • A. microannulata
  • A. folliculosa
  • Razorback Beds
  • Spores

Affinities with the genus Saccoloma, type representative of the family Saccolomataceae. This fern spore resembles those of the living genus Saccoloma, being probably from a pantropical genus found in wet, shaded forest areas.

Extant Saccoloma specimens; Annulispora probably comes from similar genera or maybe a species in the genus

Baculatisporites[23]

  • B. comaumensis

Affinities with the family Osmundaceae in the Polypodiopsida. Near fluvial current ferns, related to the modern Osmunda regalis.

Extant Osmunda specimens; Baculatisporites and Todisporites probably come from similar genera or maybe a species from the genus

Camarozonosporites[23]

  • C. spp.

Incertae sedis; affinities with the Pteridophyta

Cyathidites[23]

  • C. australis
  • C. minor

Affinities with the family Cyatheaceae in the Cyatheales. Arboreal fern spores.

Extant Cyathea

Densoisporites[23]

  • D. spp

Incertae sedis; affinities with the Pteridophyta

Dictyophyllidites[23]

  • D. mortoni

Affinities with the family Matoniaceae in the Gleicheniales.

Duplexisporites[23]

  • D. gyratus

Incertae sedis; affinities with the Pteridophyta

Foraminisporis[23]

  • F. tribulosus

Incertae sedis; affinities with the Pteridophyta

Foveosporites[23]

  • F. sp.

Incertae sedis; affinities with the Pteridophyta

Heliosporites[23]

  • H. spp

Incertae sedis; affinities with the Pteridophyta

Indusiisporites [23]

  • I. parvisaccatus

Incertae sedis; affinities with the Pteridophyta

Osmundacidites[23]

  • O. wellmanii

Affinities with the family Osmundaceae in the Polypodiopsida. Near fluvial current ferns, related to the modern Osmunda regalis.

Rugulatisporites[23]

  • R. spp.

Affinities with the family Osmundaceae in the Polypodiopsida. Near fluvial current ferns, related to the modern Osmunda regalis.

Peltaspermales

[edit]
Genus Species Stratigraphic position Material Notes Images

Alisporites[23]

  • A. australis
  • A. lowoodensis
  • A. sp.
  • Razorback Beds
  • Pollen

Affinities with the families Peltaspermaceae, Corystospermaceae or Umkomasiaceae in the Peltaspermales. Pollen of uncertain provenance that can be derived from any of the members of the Peltaspermales. The lack of distinctive characters and poor conservation make this pollen difficult to classify. Arboreal to arbustive seed ferns.

Vitreisporites[23]

  • V. contectus
  • V. pallidus

From the family Caytoniaceae in the Caytoniales. Caytoniaceae are a complex group of Mesozoic fossil floras that may be related to both Peltaspermales and Ginkgoaceae.

Conifers

[edit]
Genus Species Stratigraphic position Material Notes Images

Classopollis[23]

  • C. classoides
  • C. simplex
  • Razorback Beds
  • Pollen

Affinities with the Hirmeriellaceae in the Pinopsida.

Perinopollenites[23]

  • P. sp.

Affinities with the family Cupressaceae in the Pinopsida. Pollen that resembles that of extant genera such as the genus Actinostrobus and Austrocedrus, probably derived from dry environments.

Extant Austrocedrus

Podosporites[23]

  • P. spp.

Affinities with the family Podocarpaceae. Pollen from diverse types of Podocarpaceous conifers, that include morphotypes similar to the low arbustive Microcachrys and the medium arbustive Lepidothamnus, likely linked with Upland settings

Extant Microcachrys

See also

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References

[edit]
  1. ^ a b Vickers-Rich, Patricia (1991). Vertebrate palaeontology of Australasia. Lilydale, Vic: Pioneer Design Studio in cooperation with the Monash University Publications Committee, Melbourne. doi:10.5962/bhl.title.60647. ISBN 0-909674-36-1.
  2. ^ "Precipice Sandstone". Australian Stratigraphic Units Database. Geoscience Australia. Retrieved 6 December 2015.
  3. ^ a b Exon, N.F. (1976). "Geology of the Surat Basin in Queensland" (PDF). Bureau of Mineral Resources, Australia. Bulletin. 166 (2): 1–235.
  4. ^ Murray, C.G.; Blake, P.R.; Crouch, S.B.S.; Hayward, M.A.; Robertson, A.D.C.; Simpson, G.A. (2012). "Geology of the Yarrol Province central coastal Queensland". Queensland Geology. 13 (1): 1–675.
  5. ^ Farquhar, S. M.; Dawson, G. K. W.; Esterle, J. S.; Golding, S. D. (2013-02-01). "Mineralogical characterisation of a potential reservoir system for CO2 sequestration in the Surat Basin". Australian Journal of Earth Sciences. 60 (1): 91–110. Bibcode:2013AuJES..60...91F. doi:10.1080/08120099.2012.752406. ISSN 0812-0099.
  6. ^ Sobczak, Kasia; La Croix, Andrew D.; Esterle, Joan; Hayes, Phil; Holl, Heinz-Gerd; Ciesiolka, Rachael; Crowley, James L.; Allen, Charlotte M. (2022). "Geochronology and sediment provenance of the Precipice Sandstone and Evergreen Formation in the Surat Basin, Australia: Implications for the palaeo-geography of eastern Gondwana". Gondwana Research. 111: 189–208. Bibcode:2022GondR.111..189S. doi:10.1016/j.gr.2022.08.003. ISSN 1342-937X.
  7. ^ Bianchi, V.; Zhou, F.; Pistellato, D.; Martin, M.; Boccardo, S.; Esterle, J. (2018-04-26). "Mapping a coastal transition in braided systems: an example from the Precipice Sandstone, Surat Basin". Australian Journal of Earth Sciences. 65 (4): 483–502. Bibcode:2018AuJES..65..483B. doi:10.1080/08120099.2018.1455156. ISSN 0812-0099.
  8. ^ Martin, M.; Wakefield, M.; Bianchi, V.; Esterle, J.; Zhou, F. (2017-12-11). "Evidence for marine influence in the Lower Jurassic Precipice Sandstone, Surat Basin, eastern Australia". Australian Journal of Earth Sciences. 65 (1): 75–91. doi:10.1080/08120099.2018.1402821. ISSN 0812-0099.
  9. ^ a b c d e Romilio, Anthony; Dick, Roslyn; Skinner, Heather; Millar, Janice (2020-02-13). "Archival data provides insights into the ambiguous track-maker gait from the Lower Jurassic (Sinemurian) Razorback beds, Queensland, Australia: evidence of theropod quadrupedalism?". Historical Biology. 33 (9): 1573–1579. doi:10.1080/08912963.2020.1720014. ISSN 0891-2963.
  10. ^ a b c d Staines, HRE (1954). "Dinosaur footprints at Mount Morgan". Queensland Government Mining Journal. 55 (623): 483–485.
  11. ^ "Queensland Government: Mines and Energy: Mount Morgan Mine Site Quarterly Update: April-June 2010" (PDF). Archived from the original (PDF) on 6 July 2011. Retrieved 9 January 2011.
  12. ^ "Queensland Government: Mines and Energy: Mount Morgan Mine Rehabilitation Project: Project Summary" (PDF). Archived from the original (PDF) on 12 March 2011. Retrieved 9 January 2011.
  13. ^ Saini, N (2005). Geology and palaeo-ichnology of the Razorback beds, Mount Morgan, Queensland [Thesis]. University of Wollongong.
  14. ^ a b Romilio, Anthony (2020-04-20). "Additional notes on the Mount Morgan dinosaur tracks from the Lower Jurassic (Sinemurian) Razorback beds, Queensland, Australia". Historical Biology. 33 (10): 2005–2007. doi:10.1080/08912963.2020.1755853. ISSN 0891-2963. S2CID 218778298.
  15. ^ a b c Romilio, Anthony; Dick, Roslyn; Skinner, Heather; Millar, Janice (2024-02-21). "Uncovering hidden footprints: revision of the Lower Jurassic (Sinemurian) Razorback Beds – home to Australia's earliest reported dinosaur trackway". Historical Biology: 1–8. doi:10.1080/08912963.2024.2320184. ISSN 0891-2963.
  16. ^ a b c d e f g h i j k l m n o p La Croix, A. D.; Wang, J.; He, J.; Hannaford, C.; Bianchi, V.; Esterle, J.; Undershultz, J. R. (2019). "Widespread nearshore and shallow marine deposition within the Lower Jurassic Precipice Sandstone and Evergreen Formation in the Surat Basin, Australia". Marine and Petroleum Geology. 109 (3): 760–790. Bibcode:2019MarPG.109..760L. doi:10.1016/j.marpetgeo.2019.06.048. hdl:10289/12877. Retrieved 30 May 2023.
  17. ^ Romilio, Anthony (2020-11-12). "Evidence of ornithischian activity from the Lower Jurassic (Hettangian–Sinemurian) Precipice Sandstone, Callide Basin, Queensland, Australia — preliminary findings". Historical Biology. 33 (11): 3041–3045. doi:10.1080/08912963.2020.1846033. ISSN 0891-2963.
  18. ^ Thulborn, Richard A. (1994). "Ornithopod dinosaur tracks from the Lower Jurassic of Queensland". Alcheringa: An Australasian Journal of Palaeontology. 18 (3): 247–258. Bibcode:1994Alch...18..247T. doi:10.1080/03115519408619498. ISSN 0311-5518.
  19. ^ Romilio, Anthony; Dick, Roslyn; Skinner, Heather; Millar, Janice (2020-02-13). "Archival data provides insights into the ambiguous track-maker gait from the Lower Jurassic (Sinemurian) Razorback beds, Queensland, Australia: evidence of theropod quadrupedalism?". Historical Biology. 33 (9): 1573–1579. doi:10.1080/08912963.2020.1720014. ISSN 0891-2963.
  20. ^ a b c Cook, A. G.; Saini, N.; Hocknull, S. A. (2010). "Dinosaur footprints from the lower Jurassic of Mount Morgan, Queensland". Memoirs of the Queensland Museum-Nature. 55 (1): 135–146.
  21. ^ Kear, B. P. (2012). "A revision of Australia's Jurassic plesiosaurs". Palaeontology. 55 (5): 1125–1138. Bibcode:2012Palgy..55.1125K. doi:10.1111/j.1475-4983.2012.01183.x. Retrieved 30 May 2023.
  22. ^ Molnar, R. E. (1980). "Australian late Mesozoic continental tetrapods: some implications". Mémoires de la Société Géologique de France, Nouvelle Série. 139 (5): 131–143.
  23. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac Playford, G.; Cornelius, Kenneth D. (1967). "Palynological and lithostratigraphic features of the Razorback Beds, Mount Morgan District, Queensland". Papers Department of Geology, University of Queensland: 81–94.