Pebbly Arkose Formation

Last updated
Pebbly Arkose
Stratigraphic range: Carnian
~235–222  Ma
Pebbly-arkose-kariba.png
Pebbly arkose outcrop, Ndepa hill, Kariba District, Zimbabwe
Type Geological formation
Unit of Upper Karoo Group, Karoo Supergroup
Underlies Forest Sandstone
Overlies Escarpment Grit & Angwa Sandstone
Lithology
Primary Sandstone
Location
Coordinates 16°12′S30°18′E / 16.2°S 30.3°E / -16.2; 30.3
Approximate paleocoordinates 50°48′S11°54′E / 50.8°S 11.9°E / -50.8; 11.9
Region Mashonaland Central & West
CountryFlag of Botswana.svg  Botswana
Flag of Zambia.svg  Zambia
Flag of Zimbabwe.svg  Zimbabwe
Type section
Named forDescriptive name
Named byA.M. MacGregor, Zimbabwe Geological Survey
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Pebbly Arkose Formation (Africa)
Zimbabwe relief location map.jpg
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Pebbly Arkose Formation (Zimbabwe)

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

Contents

Geology

Description

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

Extent

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

Stratigraphy

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

Flora

Pinales of the Pebbly Arkose Formation
TaxaPresenceNotesImages
Form genus: Dadoxylon Widespread in the formation [7]

Vertebrate fauna

Archosaur
Archosaurs of the Pebbly Arkose Formation
TaxonSpeciesPresenceMaterialsNotesImages
Mbiresaurus [8] M. raathiDande Communal Land.A complete partially-articulated skeleton.An early member of Sauropodomorpha
Musankwa [9] M. sanyatiensisSpurwing Island.An articulated partial right leg.A basal massopodan sauropodomorph
Musankwa UDL.png
Massospondylus M. sp.Spurwing Island.A basal sauropodomorph.
Aetosaur [8] Indeterminate.
Herrerasaurid [8] IndeterminateDande Communal Land.
Reptiles
Rhynchosauria of the Pebbly Arkose Formation
TaxonSpeciesPresenceMaterialsNotesImages
Hyperodapedon [10] Dande, Mbire District, Zimbabwe [10]
Hyperodapedon BW2.jpg
Synapsids
Synapsida of the Pebbly Arkose Formation
TaxonSpeciesPresenceMaterialsNotesImages
Dicynodontia Indeterminate.A possible dicynodont [8]
Gomphodontosuchine [8] A traversodontid cynodont.
Fish
Fish of the Pebbly Arkose Formation
TaxonSpeciesPresenceMaterialsNotesImages
Ferganoceratodus [11] F. edwardsiA ceratodontiform lungfish

See also

Related Research Articles

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<span class="mw-page-title-main">Karoo Supergroup</span> Mesozoic stratigraphic unit in Africa

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<span class="mw-page-title-main">Beaufort Group</span> Third of the main subdivisions of the Karoo Supergroup in South Africa

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<span class="mw-page-title-main">Batoka Formation</span> Geological formation in Southern Africa

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<span class="mw-page-title-main">Molteno Formation</span> Triassic geological formation in the Stormberg Group in Lesotho and South Africa

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<span class="mw-page-title-main">Angwa Sandstone</span>

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<span class="mw-page-title-main">Upper Karoo Group</span> Sequence of Triassic to Early Jurassic rocks in southern Africa

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

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Mbiresaurus is an extinct genus of basal sauropodomorph dinosaur from the Late Triassic (Carnian) Pebbly Arkose Formation of Zimbabwe. The genus contains a single species, Mbiresaurus raathi, known from a nearly complete skeleton. Mbiresaurus represents one of Africa’s earliest known definitive dinosaurs.

<i>Musankwa</i> Genus of sauropodomorph dinosaurs

Musankwa is an extinct genus of massopodan sauropodomorph dinosaur from the Late Triassic (Norian) Pebbly Arkose Formation of Zimbabwe. The genus contains a single species, M. sanyatiensis, known from a partial leg. Musankwa represents the fourth dinosaur genus to be named from Zimbabwe.

References

  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. 1 2 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. 1 2 3 4 5 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. 1 2 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