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Lapurr Sandstone

Coordinates: 4°18′N 35°48′E / 4.3°N 35.8°E / 4.3; 35.8
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(Redirected from Turkana Grits)
Lapurr Sandstone
Stratigraphic range: Campanian-Paleocene
~72–65 Ma
TypeGeological formation
UnderliesOligocene basalt
OverliesPrecambrian metamorphic basement
Thickness400–610 m (1,310–2,000 ft)
Lithology
PrimarySandstone
Location
Coordinates4°18′N 35°48′E / 4.3°N 35.8°E / 4.3; 35.8
Approximate paleocoordinates13°48′S 27°48′E / 13.8°S 27.8°E / -13.8; 27.8
RegionRift Valley Province
Country Kenya
ExtentTurkana Basin, Great Rift Valley, Kenya
Type section
Named forLake Turkana
Lapurr Sandstone is located in Kenya
Lapurr Sandstone
Lapurr Sandstone (Kenya)

The Lapurr Sandstone, also spelled Lapur Sandstone, previously considered part of the informal "Turkana Grits", is a geological formation in Kenya (Turkana County). It is the oldest unit in the Turkana Basin. The strata date back to the Late Cretaceous, likely Campanian to Maastrichtian, based on palynology and the presence of dyrosaurs and mosasaurs, the upper part of the unit likely extends into the Palaeogene, based on zircon dating.[1] It predominantly consists of fine-coarse arkosic sandstone, which has been interpreted as either been deposited in fluvial or shallow marine conditions.[2][1] Dinosaur remains among other vertebrates have been recovered from it around Lokitaung Gorge, though these mostly consist of heavily abraded, isolated bones of robust morphology like sauropod limb bones and caudal vertebrae.[3][1]

Vertebrate paleofauna

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Dinosaurs
Taxa Presence Notes Images
Lithostrotia gen. et sp. nov.[4] Rift Valley Province, Kenya An unnamed titanosaur
Spinosaurus sp.?[5] (probably Theropoda indet.) Rift Valley Province, Kenya
Sauropoda indet Two distinct taxa
Iguanodontia indet Two distinct taxa
?Ornithopoda indet.[3] Rift Valley Province, Kenya[3]
Abelisauridae gen. et sp. nov.[6] Rift Valley Province, Kenya An unnamed giant abelisaurid, known from partial cranial and post cranial remains
Theropoda indet. Large taxon
Other reptiles
Taxa Presence Notes Images
Mosasauria indet[1] Caudal vertebra, initially misidentified as the vertebra of a pterosaur[7][1]
Dyrosauridae[1] Abundant remains
Testudines[1]

See also

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References

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  1. ^ a b c d e f g Agyemang, Prince C. Owusu; Roberts, Eric M.; Downie, Bob; Sertich, Joseph J. W. (August 2019). "Sedimentary provenance and maximum depositional age analysis of the Cretaceous? Lapur and Muruanachok sandstones (Turkana Grits), Turkana Basin, Kenya". Geological Magazine. 156 (8): 1334–1356. Bibcode:2019GeoM..156.1334A. doi:10.1017/S0016756818000663. ISSN 0016-7568. S2CID 134925592.
  2. ^ Wescott, W.A.; Morley, C.K.; Karanja, F.M. (May 1993). "Geology of the "Turkana Grits" in the Lariu range and Mt. Porr areas, southern Lake Turkana, Northwestern Kenya". Journal of African Earth Sciences (and the Middle East). 16 (4): 425–435. Bibcode:1993JAfES..16..425W. doi:10.1016/0899-5362(93)90101-U.
  3. ^ a b c Weishampel, et al. (2004). "Dinosaur distribution" Pp. 517-607. in Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. ISBN 0-520-24209-2. " Pp. 517-607.
  4. ^ "OhioLINK ETD: Gorscak, Eric". etd.ohiolink.edu. Archived from the original on 2018-08-31.
  5. ^ The dinosauria. David B. Weishampel, Peter Dodson, Halszka Osmólska (2 ed.). Berkeley, Calif.: University of California Press. 2007. ISBN 978-0-520-25408-4. OCLC 154697781.{{cite book}}: CS1 maint: others (link)
  6. ^ Sertich, J., O’Connor, P., Seiffert, E. & Manthi, F. 2013. A giant abelisaurid theropod from the latest Cretaceous of Northern Turkana, Kenya. Journal of Vertebrate Paleontology, SVP Program and Abstracts Book, 2013, pp211.
  7. ^ O'Connor PM, Sertich JJW, Manthi FK (2011) A pterodactyloid pterosaur from the Upper Cretaceous Lapurr sandstone, West Turkana, Kenya. Anais da Academia Brasileira de Ciências 83: 309–315.