The Teekloof Formation is a geological formation that forms part of the Beaufort Group, one of the five geological groups that comprises the Karoo Supergroup in South Africa. The Teekloof Formation is the uppermost formation of Adelaide Subgroup deposits West of 24ºE and contains Middle to Late Permian-aged (Guadalupian to Lopingian) deposits and four biozones (Pristerognathus, Tropidostoma, Cistecephalus, and Daptocephalus assemblage zones) of the Beaufort Group.Keyser, A. W., and 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.Keyser, A. W. (1979). A review of the biostratigraphy of the Beaufort Group in the Karoo Basin of South Africa. Geocongress, Geological Society of South Africa, 2, 13-31. It overlies the Abrahamskraal Formation (the western correlate of the Middleton Formation). The Teekloof Formation does not underlie other units other than the younger Karoo dolerites and sills that relate to the emplacement of the Early Jurassic Drakensberg Group to the east.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). Outcrops and exposures of the Teekloof Formation range from Sutherland through the mountain escarpments between Fraserburg and Beaufort West. The northernmost localities of the Teekloof Formation are found by Loxton, Victoria West and Richmond.Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience.
Geology The Teekloof Formation overlies the Abrahamskraal Formation and is not capped by any other preserved sedimentation. Only East of 24ºE does the preservation of Beaufort Group rocks continue. There is no rock preservation in the western-southwestern portions of the Karoo Basin. It is unclear whether rock preservation there ceased in the Late Permian due to localized basinal tectonics, or if that rock material was preserved but later weathered away. The Teekloof Formation has five subdivisions or members which are listed below (from oldest to youngest):
Poortjie Member - Correlates with the Lycosuchus - Eunotosaurus Subzone Endothiodon Assemblage Zone Hoedemaker Member - Correlates with the Tropidostoma - Gorgonops Subzone of the Endothiodon Assemblage Zone Oukloof Member - Correlates with the Cistecephalus Assemblage Zone Steenkampsvlakte Member - Correlates with the Daptocephalus Assemblage Zone Javanerskop Member - Correlates with the Daptocephalus Assemblage Zone
Lithologies The sedimentary rocks of this formation are predominantly reddish or minor green mudstones that are either structureless, horizontally laminated, or medium to thickly bedded. Pedogenic and diagenetic carbonate nodules and also fossil gypsum rosettes occur in the mudstone deposits. Interbedded with the mudstone deposits are minor channel sandstones ranging from pale olive to greenish-grey in colour. The sandstones are fine to medium grained and preserve fining-upward sequences (e.g. from bottom to top: Massive, horizontally laminated, trough cross-bedded, and ripple cross-laminated sedimentary structures). In the uppermost sections of the Teekloof Formation, the Javanerskop Member contains ribbon-shaped, single storied sandstones. These sandstones in the uppermost sections contain numerous erosional surfaces lined with siltstone or mudstone pellet conglomerates.
Geologists consider the Teekloof Formation depositional environment to have been a floodplain facies association that underwent seasonal arid conditions and playa lake formation as indicated by the presence of fossil gypsum rosettes and carbonate nodules. The sandstone occurrences preserve evidence of deposition on point bars in a meandering river system. Seasonal waning flood level events are indicated by the fining upward sequences.
Paleontology The Teekloof Formation is rich in fossil material and is particularly renowned for its diverse therapsid fossil fauna. Plant and invertebrate trace fossils are also found as are some preserved vertebrate fossil trackways. Well-known trackways of the pareiasaur Bradysaurus, and therapsids Diictodon and Tapinocaninus have been found by the town Fraserburg.
Paleofauna Synapsids Biarmosuchia Biarmosuchians of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesLobalopexL. mordax Victoria West HoedemakerEndothiodon AZA partial skullLophorhinusL. willodenensisHoedemaker Endothiodon AZ The anterior half of a skull. A Biarmosuchian
Therapsids
Cynodontia Cynodonts of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesAbdalodonA. diastematicusLeeukloofHoedemaker CharassognathusC. gracilis Willodene Farm Hoedemaker Endothiodon AZ A crushed skull, partial lower jaw, and a leg bone. A charassognathidae cynodontCynosaurusC. longiceps Willodene Farm Hoedemaker Endothiodon AZProcynosuchusP. delaharpeae Matjiesfortien 412 Oukloof Endothidon Az
Dicynodonts Dicynodonts of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesBulbasaurus B. phylloxyron Vredelus Hoedemaker Endothiodon AZ A skull A geikiidae dicynodontCistecephalusC. microrhinus Matjiesfortein 412 Oukloof/Steenkamp Endothiodon AZA dicynodontDiictodonD. feliceps Leeukloof and Amandelboom Farm Endothiodon AZ A dicynodontEndothiodonE. bathystoma Amandelboom Farm Poortjie Endothiodon AZ A dicynodontEmydopsE. arctatus Willodene FarmHoedemakerEndothiodon AZA dicynodontPalemydopsP. minor Leeukloof Endothiodon AZ A emydopidae dicynodontPristerodonP. mackayi LeeukloofHoedemakerEndothiodon AZ A dicynodontP. mirusOudenodonO. bainii Willodene FarmHoedemaker Endothiodon AZA dicynodontRhachiocephalusR. magnusTropidostomaT. dubium Willodene Farm Hoedemaker Endothiodon AZA dicynodont Dinocephalian Therocephalians of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesCriocephalosaurusDay MO, Guven S, Abdala F, Jirah S, Rubidge B, Almond J. Youngest dinocephalian fossils extend the Tapinocephalus Zone, Karoo Basin, South Africa. S Afr J Sci. 2015;111(3/4), Art. #2014-0309, 5 pages. http://dx.doi.org/10.17159/sajs.2015/20140309C. sp Putfortien PoortjieEndothiodon AZ Two new partial skull specimens A tapinocephalian Therocephalia Therocephalians of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesAlopecorhinusA. parvidens Poortjie Ictidognathus I. hemburyi Poortjie MicrowhaitsiaM. mendreziHoedemaker MirotenthesM. digitipes Oukloof Ophidostoma O. tatarinovi OukloofScylacoidesS. ferox
Reptiles Reptiles of the Teekloof Formation Taxa Species Locality Member Assemblage Zone Material Notes ImagesSaurorictusS. australis Leeukloof 43 HoedemakerEndothiodon AZ A partial skull A captorhinidScyllacertaS. creanae Leeukloof 43HoedemakerEndothiodon AZ An aggregation comprising at least six individuals, four of which have articulated skull. A younginidPareiasaurusP. serridens LeeukloofA pareiasaur
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