Pebbly Arkose Formation

The Pebbly Arkose Formation is a Late Triassic geologic formation found in southern Africa.

Pebbly Arkose
Stratigraphic range: Carnian
~235–222 Ma
Pebbly arkose outcrop, Ndepa hill, Kariba District, Zimbabwe
TypeGeological formation
Unit ofUpper Karoo Group, Karoo Supergroup
UnderliesForest Sandstone
OverliesEscarpment Grit & Angwa Sandstone
Lithology
PrimarySandstone
Location
Coordinates16°12′S 30°18′E / 16.2°S 30.3°E / -16.2; 30.3
Approximate paleocoordinates50°48′S 11°54′E / 50.8°S 11.9°E / -50.8; 11.9
RegionMashonaland Central & West
Country Botswana
 Zambia
 Zimbabwe
Type section
Named forDescriptive name
Named byA.M. MacGregor, Zimbabwe Geological Survey
Pebbly Arkose Formation is located in Africa
Pebbly Arkose Formation
Pebbly Arkose Formation (Africa)
Pebbly Arkose Formation is located in Zimbabwe
Pebbly Arkose Formation
Pebbly Arkose Formation (Zimbabwe)

Geology

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Description

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The formation comprises mainly coarse, arkosic sandstones.[1]

Extent

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The Pebbly Arkose Formation is found in Botswana, Zambia and Zimbabwe, in the Mid-Zambezi, Mana Pools, Cabora Bassa and Limpopo basins.

Stratigraphy

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The Pebbly Arkose Formation is part of the Upper Karoo Group, overlies the Escarpment formation (in the Mid-Zambezi and Limpopo basins)[2] and the Angwa Sandstone Formation (in the Mana Pools and Cabora Bassa Basins)[3] and underlies the Forest Sandstone Formation.[4]

The Pebbly Arkose has been correlated to the Elliot Formation of the Great Karroo Basin, South Africa[4][5] and the Mpandi Formation of the Thuli Basin in Botswana and Zimbabwe.[6]

Fossil content

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Flora

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Pinales of the Pebbly Arkose Formation
Taxa Presence Notes Images
Form genus: Dadoxylon Widespread in the formation[7]

Vertebrate fauna

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Archosaur
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Archosaurs of the Pebbly Arkose Formation
Taxon Species Presence Materials Notes Images
Mbiresaurus[8] M. raathi Dande Communal Land. A complete partially-articulated skeleton. An early member of Sauropodomorpha
Musankwa[9] M. sanyatiensis Spurwing Island. An articulated partial right leg. A basal massopodan sauropodomorph
 
Massospondylus M. sp. Spurwing Island. A basal sauropodomorph.
Aetosaur[8] Indeterminate.
Herrerasaurid[8] Indeterminate Dande Communal Land.
Reptiles
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Rhynchosauria of the Pebbly Arkose Formation
Taxon Species Presence Materials Notes Images
Hyperodapedon[10] Dande, Mbire District, Zimbabwe[10]
 
Synapsids
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Synapsida of the Pebbly Arkose Formation
Taxon Species Presence Materials Notes Images
Dicynodontia Indeterminate. A possible dicynodont[8]
Gomphodontosuchine[8] A traversodontid cynodont.
Fish
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Fish of the Pebbly Arkose Formation
Taxon Species Presence Materials Notes Images
Ferganoceratodus[11] F. edwardsi A ceratodontiform lungfish

See also

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References

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  1. ^ Love, David; Ravengai, S.; Katemaunzanga, D.; Shoko, D.S.M.; Kambewa, C.; Matura, N.E. (July 2004). "The Karoo sequence in the Nyaminyami area, Zambezi Valley, Zimbabwe". Abstract volume, Geoscience Africa Conference. Johannesburg, South Africa: Geological Society of South Africa. p. 135.
  2. ^ Bordy, Emese M.; Catuneanu, Octavian (2001). "Sedimentology of the upper Karoo fluvial strata in the Tuli Basin, South Africa". Journal of African Earth Sciences. 33 (3–4): 605. Bibcode:2001JAfES..33..605B. doi:10.1016/S0899-5362(01)00090-2.
  3. ^ d'Engelbronner, E.R. (1996). "New palynological data from Karoo sediments, Mana Pools basin, northern Zimbabwe". Journal of African Earth Sciences. 23 (1): 17–30. Bibcode:1996JAfES..23...17D. doi:10.1016/S0899-5362(96)00049-8.
  4. ^ a b Nyambe, Imasiku A.; Utting, John (1997). "Stratigraphy and palynostratigraphy, Karoo Supergroup (Permian and Triassic), mid-Zambezi Valley, southern Zambia". Journal of African Earth Sciences. 24 (4): 563. Bibcode:1997JAfES..24..563N. doi:10.1016/S0899-5362(97)00081-X.
  5. ^ Catuneanu, O.; Wopfner, H.; Eriksson, P.G.; Cairncross, B.; Rubidge, B.S.; Smith, R.M.H.; Hancox, P.J. (2005). "The Karoo basins of south-central Africa". Journal of African Earth Sciences. 43 (1–3): 211–253. Bibcode:2005JAfES..43..211C. doi:10.1016/j.jafrearsci.2005.07.007.
  6. ^ Rogers, Raymond R.; Rogers, Kristina Curry; Munyikwa, Darlington; Terry, Rebecca C.; Bradley s.Singer (2004). "Sedimentology and taphonomy of the upper Karoo-equivalent Mpandi Formation in the Tuli Basin of Zimbabwe, with a new 40Ar/39Ar age for the Tuli basalts" (PDF). Journal of African Earth Sciences. 40 (3–4): 147. Bibcode:2004JAfES..40..147R. doi:10.1016/j.jafrearsci.2004.11.004.
  7. ^ Nugent, Chris (1990). "The Zambezi River: Tectonism, climatic change and drainage evolution". Palaeogeography, Palaeoclimatology, Palaeoecology. 78 (1–2): 55–69. Bibcode:1990PPP....78...55N. doi:10.1016/0031-0182(90)90204-K.
  8. ^ a b c d e Griffin CT, Wynd BM, Munyikwa D, Broderick TJ, Zondo M, Tolan S, Langer MC, Nesbitt SJ, Taruvinga HR (2022). "Africa's oldest dinosaurs reveal early suppression of dinosaur distribution". Nature. 609 (7926): 313–319. Bibcode:2022Natur.609..313G. doi:10.1038/s41586-022-05133-x. PMID 36045297.
  9. ^ Barrett, Paul M.; Chapelle, Kimberley E.J.; Sciscio, Lara; Broderick, Timothy J.; Zondo, Michel; Munyikwa, Darlington; Choiniere, Jonah N. "A new Late Triassic sauropodomorph dinosaur from the Mid-Zambezi Basin, Zimbabwe". Acta Palaeontologica Polonica. 69 (2): 227–241. doi:10.4202/app.01100.2023.
  10. ^ a b Raath, MA, Oesterlen PM, Kitching JW (1992). "First record of Triassic Rhynchosauria (Reptilia: Diapsida) from the lower Zambezi Valley, Zimbabwe". Palaentologia Africana. 29: 1–10.
  11. ^ Challands, T. J.; Cavin, L.; Zondo, M.; Munyikwa, D.; Choiniere, J. N.; Barrett, P. M. (2024). "A new lungfish from the Upper Triassic of the Mid-Zambezi Basin, Zimbabwe". Journal of Vertebrate Paleontology. e2365391. doi:10.1080/02724634.2024.2365391.

Bibliography

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