Earth:Beaufort Group
Beaufort Group Stratigraphic range: Guadalupian-Early Triassic ~268–247 Ma | |
---|---|
Type | Geologic group |
Underlies | Stormberg Group |
Overlies | Ecca Group |
Thickness | up to 22,965.88 feet (7,000 m) |
Lithology | |
Primary | Mudstone, claystone, siltstone |
Other | Sandstone, shale, Tuff |
Location | |
Region | Northern Cape, Western, Eastern Cape, KwaZulu-Natal, Free State. |
Country | South Africa |
Extent | 145 000 km squared |
A simplified geological map of the outcrops of Karoo Supergroup rocks in Southern Africa. The Beaufort Group is represented by the yellow key on the map. |
The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa . It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup.[1][2] It follows conformably after the Ecca Group and unconformably underlies the Stormberg Group. Based on stratigraphic position, lithostratigraphic and biostratigraphic correlations,[3] palynological analyses, and other means of geological dating, the Beaufort Group rocks are considered to range between Middle Permian (Wordian) to Early Triassic (Anisian) in age.[4][5]
Background
During the period when sedimentation of the Beaufort Group rocks took place, the Ecca sea had retreated to the northeastern Karoo Basin. All sediment deposition at this time took place in a terrestrial, although in a predominantly fluvial or alluvial environment that was seasonally arid. This environment covered a vast area and deposition was influenced by a retroarc foreland basin. This foreland system was caused by crustal uplift (orogenesis) that had previously begun to take course due to the subduction of the Palaeo-pacific plate beneath the Gondwanan Plate. This resulted in the rise of the Gondwanide mountain range in what is known as the Gondwanide orogeny. The continuation of mountain-building and erosion from the growing Gondwanide mountain chain and associated subduction created accommodation space for sediment deposition in the Karoo Basin. Orogenic loading was the initial subsidence mechanism acting on the Karoo Basin and flexural tectonics partitioned the Karoo Basin into the foredeep, forebulge, and backbulge flexural provinces. Orogenic loading and unloading caused changes in position of the forebulge and foredeep. This resulted in the deposition zones shifting from the proximal or distal regions of the Karoo Basin.[6]
The Beaufort Group rocks are predominantly mudstone-dominated up until the upper sections in the lower Tarkastad Subgroup. Tuffs are also found due to concurrent volcanic activity that took place with the foreland tectonics.[7][8][9][10]
Geographic extent
The geological formations of the Beaufort Group are outcrop over approximately 145 000 km2, attaining a total thickness of around 6000 m thick at its thickest outcrops. In the west, the lowermost Beaufort Group rocks are found east of Laingsburg and remain continuous eastward to East London. Deposits are also found in the central Karoo and continue north-north-eastwards to Gariep Dam, Colesberg, and up to Bloemfontein. In the extreme north and north-east, the Beaufort Group outcrops in Harrismith and northeastern KwaZulu-Natal.
Stratigraphic units
Adelaide Subgroup
The Adelaide Subgroup is the lower subgroup of the Beaufort Group and contains all Middle to Late Permian-aged rocks. This subgroup contains six geological formations in total, however, these formations are latitude specific. These formations are the Abrahaamskraal and Teekloof Formations, west of 24°E, Middleton and Balfour Formations east of 24°E, and the Normandien and Emakwezini Formations in the northern Free-State and Kwa-Zulu Natal provinces. Composing the lower Beaufort succession, the rocks are mudstone-dominated. The mudstones in the lower Beaufort Group are mainly greenish-grey to blueish-grey and gradually change to greyish-red, reddish-brown or purple in color. The dominant presence of mudstones in the lower Beaufort Group represent tranquil depositional settings such as overbank or floodplain facies associations. The formations here are listed below (from oldest to youngest):
West of 24 degrees
- Abrahamskraal Formation: The Abrahamskraal Formation is found in both its western and eastern deposits. Previously, east of 24 degrees deposits of the Abrahaamskraal Formation were known as the Koonap Formation.[11] Recently these were amalgamated into the Abrahaamskraal Formation due to recent stratigraphic and biostratigraphic research.[12][13][14][15][16]
- Teekloof Formation: Floodplain facies association comprising some greenish-grey mudstones. However, redder mudstones are dominant.[17]
East of 24 degrees
- Middleton Formation: Lies conformably over the Abrahamskraal Formation in the east. Semi-arid climate supported a lush flora and fauna that thrived along meander belts and semi-permanent lakes. The formation contains lenses of red mudstone which are likely to have been deposited in a sub-aerial fluvial environment.[17]
- Balfour Formation: Low-energy, fluvial environmental facies, most likely one that had meandering rivers. Mudstone-rich.[18][19][20]
- Normadien Formation (northeastern region only): Mudstone-rich, but these are interbedded with diagnostic layers of very coarse-grained sandstones that exhibit coarsening upward cycles.
- Emakwezini Formation (northeastern KwaZulu-Natal only): An extremely understudied geological formation that outcrops in a thin, faulted, and meridional belt in central Eswatini and the southern Lebombo Basin of northeastern KwaZulu-Natal. It is actively mined for its coal seams which are found intercalated with fine, greenish-grey to brown mudstones and carbonaceous shales. The mudstones contain layers of fining upward successions of coarse-grained, yellow-white sandstones. Rare limestone lenses are sometimes also found. The mudstones have yielded diverse fossils, mainly of plants such as Phyllotheca, Glossopteris and associated Dictyopteridium. Insect fossils are also found, such as of Neoliomopterum picturatum, various mollusc fossils, fish scales of Coelacanthus dendrites and unidentified ganoid fish scales and teeth. Being upper Permian in age, it correlates with the Normandien and Balfour Formations, but is differentiated from these two formations due to its unique sedimentary facies structure. Unlike the rest of the Beaufort Group sequence, the Emakwezini Formation was deposited in a permanently wet, fluvial-lacustrine environment where peat swamps were present.[21][22][23][24]
Tarkastad Subgroup
There are no equivalent deposits of the Tarkastad Subgroup west of 24°E. This is either due to erosion of the lowlands west of 24°E or sediment deposition in the western section of the Karoo Basin ceased at the end of the Permian. In the lower sections sandstones dominate, especially in the Katberg Formation. In the upper units the sandstone to mudstone ratio steadily evens out.[25] The Tarkastad Subgroup is composed of the following formations (from oldest to youngest):
- Katberg Formation: Dominated by fine to medium-grained sandstones. Alluvial fan and braided river environmental facies.[26]
- Burgersdorp Formation: Very mudstone-rich which are reddish or purple in color.
- Verkykerskop Formation (extreme northeast only): Composed entirely of fine-grained sandstone interbedded with very coarse sandstones.
- Driekoppen Formation (extreme northeast only): Nearly entirely composed of mudstone.[27]
Paleontology
The Beaufort Group is internationally renowned for its diverse fossil fauna,[28][29][30][31][32][33][34][35][36] in particular for its therapsid fossils.[37][38][39][40][41][42][43][44][45][46] The entire expanse of this geological group has been categorized into eight fossil biozones or assemblage zones.[47][48][49][50][51] These assemblage zones are listed below:
- Cynognathus Assemblage Zone (Youngest)
- Lystrosaurus Assemblage Zone
- Daptocephalus Assemblage Zone
- Cistecephalus Assemblage Zone
- Tropidostoma Assemblage Zone
- Pristerognathus Assemblage Zone
- Tapinocephalus Assemblage Zone
- Eodicynodon Assemblage Zone (Oldest)
The Beaufort Group deposits also yield numerous insect, plant, and trace fossils.[52][53][54]
Correlation
The Beaufort Group rocks correlate chronologically with numerous other geological formations and groups within southern Africa[55] and abroad. Most notably from numerous localities in Russia ,[56][57] China ,[58] South America,[59][60][61][62] Antarctica, Madagascar , India , and Australia .[63]
See also
References
- ↑ Keyser, A. W., & Smith, R. M. H. (1978). Vertebrate biozonation of the Beaufort Group with special reference to the western Karoo Basin. Geological Survey, Department of Mineral And Energy Affairs, Republic of South Africa.
- ↑ Smith, R.M.H., Eriksson, P.G. and Botha, W.J. (1993-01-01). "A review of the stratigraphy and sedimentary environments of the Karoo-aged basins of Southern Africa" (in en). Journal of African Earth Sciences (and the Middle East) 16 (1–2): 143–169. doi:10.1016/0899-5362(93)90164-L. ISSN 0899-5362. Bibcode: 1993JAfES..16..143S.
- ↑ Rubidge, B. S.; Hancox, P. J. (1997). "The role of fossils in interpreting the development of the Karoo Basin" (in en). Palaeontologia Africana. ISSN 0078-8554. http://wiredspace.wits.ac.za/handle/10539/16396.
- ↑ Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience.
- ↑ Jirah, Sifelani; McPhee, Blair W.; Viglietti, Pia A.; Bamford, Marion K.; Choiniere, Jonah N.; Hancox, P. John; Barbolini, Natasha; Day, Michael O. et al. (2016), "Advances in Nonmarine Karoo Biostratigraphy: Significance for Understanding Basin Development" (in en), Origin and Evolution of the Cape Mountains and Karoo Basin, Regional Geology Reviews (Springer, Cham): pp. 141–149, doi:10.1007/978-3-319-40859-0_14, ISBN 9783319408583
- ↑ Clevis, Quintijn; Boer, Poppe L. De; Nijman, Wouter (2004). "Differentiating the effect of episodic tectonism and eustatic sea-level fluctuations in foreland basins filled by alluvial fans and axial deltaic systems: insights from a three-dimensional stratigraphic forward model" (in en). Sedimentology 51 (4): 809–835. doi:10.1111/j.1365-3091.2004.00652.x. ISSN 1365-3091. Bibcode: 2004Sedim..51..809C.
- ↑ Waschbusch, Paula; Beaumont, Christopher; Catuneanu, Octavian (1997-12-01). "Interplay of static loads and subduction dynamics in foreland basins: Reciprocal stratigraphies and the "missing" peripheral bulge" (in en). Geology 25 (12): 1087–1090. doi:10.1130/0091-7613(1997)025<1087:IOSLAS>2.3.CO;2. ISSN 0091-7613. Bibcode: 1997Geo....25.1087C.
- ↑ Rubidge, B. S.; Hancox, P. J.; Catuneanu, O. (1998-12-01). "Reciprocal flexural behaviour and contrasting stratigraphies: a new basin development model for the Karoo retroarc foreland system, South Africa" (in en). Basin Research 10 (4): 417–439. doi:10.1046/j.1365-2117.1998.00078.x. ISSN 1365-2117. Bibcode: 1998BasR...10..417C. http://www.earthdoc.org/publication/publicationdetails/?publication=62697.
- ↑ Catuneanu, O.; Hancox, P. J.; Rubidge, B. S. (2000-03-01). "Sequence analysis of the Ecca—Beaufort contact in the southern Karoo of South Africa" (in en). South African Journal of Geology 103 (1): 81–96. doi:10.2113/103.1.81. ISSN 1012-0750.
- ↑ Catuneanu, O., Hancox, P., Cairncross, B. & Rubidge, B. (2002-11-01). "Foredeep submarine fans and forebulge deltas: orogenic off-loading in the underfilled Karoo Basin" (in en). Journal of African Earth Sciences 35 (4): 489–502. doi:10.1016/S0899-5362(02)00154-9. ISSN 1464-343X. Bibcode: 2002JAfES..35..489C.
- ↑ Bottjer, David J.; Shen, Shuzhong; Clapham, Matthew E. (2009-04-08). "The double mass extinction revisited: reassessing the severity, selectivity, and causes of the end-Guadalupian biotic crisis (Late Permian)" (in en). Paleobiology 35 (1): 32–50. doi:10.1666/08033.1. ISSN 1938-5331. https://www.cambridge.org/core/journals/paleobiology/article/double-mass-extinction-revisited-reassessing-the-severity-selectivity-and-causes-of-the-endguadalupian-biotic-crisis-late-permian/2DAC8E0FBA521986AE878E8A2469AA8D.
- ↑ Catuneanu, O. & Bowker, D. (2001-01-01). "Sequence stratigraphy of the Koonap and Middleton fluvial formations in the Karoo foredeep South Africa" (in en). Journal of African Earth Sciences 33 (3–4): 579–595. doi:10.1016/S0899-5362(01)00095-1. ISSN 1464-343X. Bibcode: 2001JAfES..33..579C.
- ↑ Day, M.O. and Rubidge, B.S. (2014-12-01). "A brief lithostratigraphic review of the Abrahamskraal and Koonap formations of the Beaufort Group, South Africa: Towards a basin-wide stratigraphic scheme for the Middle Permian Karoo" (in en). Journal of African Earth Sciences 100: 227–242. doi:10.1016/j.jafrearsci.2014.07.001. ISSN 1464-343X. Bibcode: 2014JAfES.100..227D.
- ↑ Jirah, S. (2014-12-01). "Refined stratigraphy of the Middle Permian Abrahamskraal Formation (Beaufort Group) in the southern Karoo Basin" (in en). Journal of African Earth Sciences 100: 121–135. doi:10.1016/j.jafrearsci.2014.06.014. ISSN 1464-343X. Bibcode: 2014JAfES.100..121J.
- ↑ Day, M. O.; Johnson, M. R.; Cole, D. I. (2016-06-01). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa" (in en). South African Journal of Geology 119 (2): 415–424. doi:10.2113/gssajg.119.2.415. ISSN 1012-0750.
- ↑ Lucas, S. G. (2001). "A Global Hiatus in the Middle Permian Tetrapod Fossil Record". Permophiles 38: 24–27.
- ↑ 17.0 17.1 Day, Michael Oliver (2014-03-04). Middle Permian continental biodiversity changes as reflected in the Beaufort Group of South Africa: a bio- and lithostratigraphic review of the Eodicynodon, Tapinocephalus and Pristerognathus assemblage zones (Thesis thesis).
- ↑ Viglietti, P. A., Smith, R. M., Angielczyk, K. D., Kammerer, C. F., Fröbisch, J., & Rubidge, B. S. (2016-01-01). "The Daptocephalus Assemblage Zone (Lopingian), South Africa: A proposed biostratigraphy based on a new compilation of stratigraphic ranges" (in en). Journal of African Earth Sciences 113: 153–164. doi:10.1016/j.jafrearsci.2015.10.011. ISSN 1464-343X. Bibcode: 2016JAfES.113..153V.
- ↑ Viglietti, Pia; Rubidge, Bruce; Malcom Harris Smith, Roger (2017-03-01). "Revised lithostratigraphy of the upper Permian Balfour and Teekloof formations of the main Karoo Basin, South Africa". South African Journal of Geology 120 (3–4): 45–60. doi:10.25131/gssajg.120.1.45. https://www.researchgate.net/publication/319543960.
- ↑ Katemaunzanga, David; Gunter, Cornelis Janse (2009). "Lithostratigraphy, Sedimentology, and Provenance of the Balfour Formation (Beaufort Group) in the Fort Beaufort–Alice Area, Eastern Cape Province, South Africa" (in en). Acta Geologica Sinica - English Edition 83 (5): 902–916. doi:10.1111/j.1755-6724.2009.00110.x. ISSN 1755-6724.
- ↑ Jourbert, M.R., 1994. Emakwezini Formation. Lexicon of South African Stratigraphy: Part, 1.
- ↑ Prevec, R.; Bordy, E. M. (2008-12-01). "Sedimentology, palaeontology and palaeo-environments of the Middle (?) to Upper Permian Emakwezini Formation (Karoo Supergroup, South Africa)" (in en). South African Journal of Geology 111 (4): 429–458. doi:10.2113/gssajg.111.4.429. ISSN 1012-0750.
- ↑ Aristov, D.S., Prevec, R. and Mostovski, M.B., 2009. (2009). "New and poorly known grylloblattids (Insecta: Grylloblattida) from the Lopingian of the Lebombo Basin, South Africa". African Invertebrates 50 (2): 279–286. doi:10.5733/afin.050.0205.
- ↑ Prevec, R.; Bordy, E. M. (2015-09-01). "Lithostratigraphy of the Emakwezini Formation (Karoo Supergroup), South Africa" (in en). South African Journal of Geology 118 (3): 307–310. doi:10.2113/gssajg.118.3.307. ISSN 1012-0750.
- ↑ R.M.H. Smith (1995-08-01). "Changing fluvial environments across the Permian-Triassic boundary in the Karoo Basin, South Africa and possible causes of tetrapod extinctions" (in en). Palaeogeography, Palaeoclimatology, Palaeoecology 117 (1–2): 81–104. doi:10.1016/0031-0182(94)00119-S. ISSN 0031-0182. Bibcode: 1995PPP...117...81S.
- ↑ Viglietti, P.A., Smith, R.M.H. and Compton, J. (2013-12-15). "Origin and palaeoenvironmental significance of Lystrosaurus bonebeds in the earliest Triassic Karoo Basin, South Africa" (in en). Palaeogeography, Palaeoclimatology, Palaeoecology 392: 9–21. doi:10.1016/j.palaeo.2013.08.015. ISSN 0031-0182. Bibcode: 2013PPP...392....9V.
- ↑ Johnson, M.R.; Van Vuuren, C.J.; Visser, J.N.J.; Cole, D.I.; Wickens, H. (2006). "Sedimentary rocks of the Karoo Supergroup". The Geology of South Africa Geological. Society of South Africa/Council for Geoscience 461: 499.
- ↑ Cisneros, J. C., Rubidge, B. S., Mason, R. & Dube, C. (2008). "Analysis of millerettid parareptile relationships in the light of new material of Broomia perplexa Watson, 1914, from the Permian of South Africa". Journal of Systematic Palaeontology 6 (4): 453–462. doi:10.1017/s147720190800254x.
- ↑ Damiani, R. J. (2004-01-01). "Temnospondyls from the Beaufort Group (Karoo Basin) of South Africa and Their Biostratigraphy" (in en). Gondwana Research 7 (1): 165–173. doi:10.1016/S1342-937X(05)70315-4. ISSN 1342-937X. Bibcode: 2004GondR...7..165D.
- ↑ Reisz, Robert R.; Laurin, Michel (January 1991). "Owenetta and the origin of turtles" (in en). Nature 349 (6307): 324–326. doi:10.1038/349324a0. ISSN 1476-4687. Bibcode: 1991Natur.349..324R. https://doi.org/10.1038/349324a0.
- ↑ Reisz, Robert R.; Scott, Diane (8 July 2002). [0244:OKSNAS2.0.CO;2 "Owenetta kitchingorum, sp. nov., a small parareptile (Procolophonia: Owenettidae) from the Lower Triassic of South Africa"]. Journal of Vertebrate Paleontology 22 (2): 244–256. doi:10.1671/0272-4634(2002)022[0244:OKSNAS2.0.CO;2]. ISSN 0272-4634. https://doi.org/10.1671/0272-4634(2002)022[0244:OKSNAS]2.0.CO;2.
- ↑ Reisz, R. R., Dilkes, D. W. & Berman, D. S. 1998. (1998). "Anatomy and relationships of Elliotsmithia longiceps Broom, a small synapsid (Eupelycosauria: Varanopseidae) from the Late Permian of South Africa". Journal of Vertebrate Paleontology 18 (3): 602–611. doi:10.1080/02724634.1998.10011087.
- ↑ Surkov, M. V.; Tverdokhlebov, V. P.; Benton, M. J. (2004-11-01). "Ecosystem remodelling among vertebrates at the Permian–Triassic boundary in Russia" (in en). Nature 432 (7013): 97–100. doi:10.1038/nature02950. ISSN 1476-4687. PMID 15525988. Bibcode: 2004Natur.432...97B. http://doc.rero.ch/record/15286/files/PAL_E2585.pdf.
- ↑ Almond, John; Rubidge, Bruce; Jirah, Sifelani; Abdala, Fernando; Güven, Saniye; Day, Michael O. (2015-04-01). "Youngest dinocephalian fossils extend the Tapinocephalus Zone, Karoo Basin, South Africa". South African Journal of Science 111 (3–4): 1–5. doi:10.17159/sajs.2015/20140309. ISSN 0038-2353.
- ↑ Lyson, T.R., Bever, G.S., Scheyer, T.M., Hsiang, A.Y. and Gauthier, J.A., 2013. (2013-06-17). "Evolutionary Origin of the Turtle Shell" (in en). Current Biology 23 (12): 1113–1119. doi:10.1016/j.cub.2013.05.003. ISSN 0960-9822. PMID 23727095.
- ↑ Botha-Brink, J. and Smith, R.M., 2011. (2011). "Osteohistology of the Triassic archosauromorphs Prolacerta, Proterosuchus, Euparkeria, and Erythrosuchus from the Karoo Basin of South Africa". Journal of Vertebrate Paleontology 31 (6): 1238–1254. doi:10.1080/02724634.2011.621797.
- ↑ Broom, R (1906). "V.—On the Permian and Triassic Faunas of South Africa". Geological Magazine 3 (1): 29–30. doi:10.1017/s001675680012271x. Bibcode: 1906GeoM....3...29B. https://zenodo.org/record/1687495.
- ↑ Broom, R (1935). "On some new genera and species of Karroo fossil reptiles". Annals of the Transvaal Museum 18: 55–72.
- ↑ Broom, R (1948). "A contribution to our knowledge of the vertebrates of the Karroo Beds of South Africa". Transactions of the Royal Society of Edinburgh 61 (2): 577–629. doi:10.1017/s0080456800004865.
- ↑ Cluver, M. A. (1975). "A new dicynodont reptile from the Tapinocephalus Zone (Karoo System, Beaufort series) of South Africa, with evidence of the jaw adductor musculature". Annals of the South African Museum 67: 7–23.
- ↑ Cluver, M. A.; King, G. M. (1983). "A reassessment of the relationships of Permian Dicynodontia (Reptilia, Therapsida) and a new classification of dicynodonts". Annals of the South African Museum 91: 195–273.
- ↑ Boonstra, L.D., 1969. The fauna of the Tapinocephalus Zone (Beaufort beds of the Karoo).
- ↑ Rubidge, B.S., King, G.M. and Hancox, P.J., 1994.. "The postcranial skeleton of the earliest dicynodont synapsid Eodicynodon from the Upper Permian of South Africa | Request PDF" (in en). https://www.researchgate.net/publication/239523242.
- ↑ Laurin, Michel (1998). "New Data on the Cranial Anatomy of Lycaenops (Synapsida, Gorgonopsidae), and Reflections on the Possible Presence of Streptostyly in Gorgonopsians". Journal of Vertebrate Paleontology 18 (4): 765–776. doi:10.1080/02724634.1998.10011105. ISSN 0272-4634. http://www.jstor.org/stable/4523954.
- ↑ Modesto, Sean; Rubidge, Bruce; Visser, Ian; Welman, Johann (2003-01-01). "A new basal dicynodont from the Upper Permian of South Africa". Palaeontology 46 (1): 211–223. doi:10.1111/1475-4983.00295. ISSN 0031-0239.
- ↑ Lucas, Spencer G.; Zeigler, Kate E. (2005) (in en). The Nonmarine Permian: Bulletin 30. New Mexico Museum of Natural History and Science. https://books.google.com/books?id=7r75CQAAQBAJ&q=+Lucas,+S.+G.+2005a.+Dicynodon+(Reptilia:Therapsida)+from+the+Upper+Permian+of+Russia:+Biochronologic+significance.+New+Mexico+Museum+of+Natural+History+and+Science+Bulletin,+30,+192%E2%80%93196.&pg=PA192.
- ↑ Bain, A.G. (1845). "On the discovery of the fossil remains of bidental and other reptiles in South Africa". Quarterly Journal of the Geological Society 1 (1): 317–318. doi:10.1144/gsl.jgs.1845.001.01.72. https://zenodo.org/record/1673362.
- ↑ Seeley, H.G. (1892). "Researches on the structure, organization, and classification of the fossil Reptilia. VII. Further observations on Pareiasaurus". Philosophical Transactions of the Royal Society of London B 183: 311–370. doi:10.1098/rstb.1892.0008.
- ↑ Watson, D.M.S. (1914). "II.—The Zones of the Beaufort Beds of the Karroo System in South Africa". Geological Magazine 1 (5): 203–208. doi:10.1017/s001675680019675x. Bibcode: 1914GeoM....1..203W. https://zenodo.org/record/1506035.
- ↑ Kitching, J. W. (1970). A short review of the Beaufort zoning in South Africa. In Second Gondwana Symposium Proceedings and Papers (Vol. 1, pp. 309-312).
- ↑ van der Walt, Merrill; Day, Michael; Rubidge, Bruce; Cooper, Antony; Netterberg, Inge (2010-12-31). "A new GIS-based biozone map of the Beaufort Group (Karoo Supergroup), South Africa". Palaeontologia Africana 45: 1–6. https://www.researchgate.net/publication/239521002.
- ↑ Anderson, J. M. (1973). "THE BIOSTRATIGRAPHY OF THE PERMIAN AND TRIASSIC" (in en). Palaeontologia Africana. ISSN 0078-8554. http://wiredspace.wits.ac.za/handle/10539/16041.
- ↑ Rubidge, Bruce S. (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)" (in en). Palaeontologia Africana. ISSN 0078-8554. http://wiredspace.wits.ac.za/handle/10539/16155.
- ↑ Bamford, M.K. (2004-01-01). "Diversity of the Woody Vegetation of Gondwanan Southern Africa" (in en). Gondwana Research 7 (1): 153–164. doi:10.1016/S1342-937X(05)70314-2. ISSN 1342-937X. Bibcode: 2004GondR...7..153B.
- ↑ Sidor, C.A., Angielczyk, K.D., Smith, R.M., Goulding, A.K., Nesbitt, S.J., Peecook, B.R., Steyer, J.S. and Tolan, S., 2014. (2014). "Tapinocephalids (Therapsida, Dinocephalia) from the Permian Madumabisa Mudstone Formation (Lower Karoo, Mid-Zambezi Basin) of southern Zambia". Journal of Vertebrate Paleontology 34 (4): 980–986. doi:10.1080/02724634.2013.826669.
- ↑ Benton, Michael J.; Shishkin, Mikhail A.; Unwin, David M.; Kurochkin, Evgenii N. (2003-12-04) (in en). The Age of Dinosaurs in Russia and Mongolia. Cambridge University Press. ISBN 9780521545822. https://books.google.com/books?id=NzVGpo3M998C&q=Chudinov,+P.+K.+1969.+%5BOn+the+stratigraphic+distribution+of+Permian+vertebrates+in+eastern+European+parts+of+the+USSR.%5D.+%5BQuestions+on+the+Geology+of+the+South+Urals+and+Volga+Region%5D,+96%E2%80%93105.+Saratov:+Izdatel'stvo+Saratovskogo+Universiteta.+Chudinov,&pg=PA1.
- ↑ Laurin, Michel; Hook, Robert W. (2022). "The age of North America's youngest Paleozoic continental vertebrates: a review of data from the Middle Permian Pease River (Texas) and El Reno (Oklahoma) Groups" (in en). BSGF - Earth Sciences Bulletin 193: 10. doi:10.1051/bsgf/2022007. https://doi.org/10.1051/bsgf/2022007.
- ↑ Bond, D. P. G., Wignall, P. B., Wang, W., Izon, G., Jiang, H. S., Lai, X. L., Sun, Y. D., Newton, R. J., Shao, L. Y., Védrine, S. & Cope, H. (2010-06-01). "The mid-Capitanian (Middle Permian) mass extinction and carbon isotope record of South China" (in en). Palaeogeography, Palaeoclimatology, Palaeoecology 292 (1–2): 282–294. doi:10.1016/j.palaeo.2010.03.056. ISSN 0031-0182. Bibcode: 2010PPP...292..282B.
- ↑ Bueno, Ana de Oliveira; Dentzien-Dias, Paula Camboim; Rubidge, Bruce S.; Abdala, Fernando; Cisneros, Juan Carlos (2011-03-25). "Dental Occlusion in a 260-Million-Year-Old Therapsid with Saber Canines from the Permian of Brazil" (in en). Science 331 (6024): 1603–1605. doi:10.1126/science.1200305. ISSN 1095-9203. PMID 21436452. Bibcode: 2011Sci...331.1603C.
- ↑ Boos, A.D.S., Kammerer, C.F., Schultz, C.L. and Neto, V.P. (2015-11-01). "A tapinocephalid dinocephalian (Synapsida, Therapsida) from the Rio do Rasto Formation (Paraná Basin, Brazil): Taxonomic, ontogenetic and biostratigraphic considerations" (in en). Journal of South American Earth Sciences 63: 375–384. doi:10.1016/j.jsames.2015.09.003. ISSN 0895-9811. Bibcode: 2015JSAES..63..375B.
- ↑ Schultz, Cesar L.; Şengör, A. M. Celâl; Rubidge, Bruce S.; Atayman-Güven, Saniye; Abdala, Fernando; Cisneros, Juan Carlos (2012-01-31). "Carnivorous dinocephalian from the Middle Permian of Brazil and tetrapod dispersal in Pangaea" (in en). Proceedings of the National Academy of Sciences 109 (5): 1584–1588. doi:10.1073/pnas.1115975109. ISSN 1091-6490. PMID 22307615. Bibcode: 2012PNAS..109.1584C.
- ↑ Cisneros, J.C., Abdala, F., Jashashvili, T., de Oliveira Bueno, A. and Dentzien-Dias, P., 2015. (2015). "Tiarajudens eccentricus and Anomocephalus africanus, two bizarre anomodonts (Synapsida, Therapsida) with dental occlusion from the Permian of Gondwana". Royal Society Open Science 2 (7): 150090. doi:10.1098/rsos.150090. PMID 26587266. Bibcode: 2015RSOS....250090C.
- ↑ Wit, M. J. De; Milani, E. J. (2008-01-01). "Correlations between the classic Paraná and Cape–Karoo sequences of South America and southern Africa and their basin infills flanking the Gondwanides: du Toit revisited" (in en). Geological Society, London, Special Publications 294 (1): 319–342. doi:10.1144/SP294.17. ISSN 2041-4927. Bibcode: 2008GSLSP.294..319M. http://sp.lyellcollection.org/content/294/1/319.
Original source: https://en.wikipedia.org/wiki/Beaufort Group.
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