Lealt Shale

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Lealt Shale Formation
Stratigraphic range: Bathonian
O
S
D
C
P
T
J
K
Pg
N
Lealt Shale Lava.jpg
Thinly bedded limestones of the Lealt Shale formation overlain by Paleogene lava
Type Geological formation
Unit of Great Estuarine Group
Sub-unitsKildonnan Member, Lonfearn Member
Underlies Valtos Sandstone Formation
Overlies Elgol Sandstone Formation
ThicknessBetween 45 and 50 m
Lithology
Primary Mudstone
Other Limestone
Location
Region Europe
CountryFlag of Scotland.svg  Scotland
Extent Inner Hebrides
Type section
Named for Lealt, Skye
Named byHarris and Hudson
LocationCliffs east of Lonfearn (partial), Coastal exposure 2.5 km north of Kildonnan, Eigg (partial)
Year defined1980
Thickness at type sectionLonfearn: 26 to 30 m (partial) Kildonnan: 23 m (partial)

The Lealt Shale Formation is a Middle Jurassic geologic formation in Scotland. Fossil ornithopod, theropod and stegosaur tracks, a theropod dinosaur tooth and the pterosaur Dearc have been reported from the formation. [1] [2] [3] The lithology consists of silty fissile mudstones with subordinate thin limestones. [4]

Contents

Fossil content

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs

Theropoda

Theropod of the Lealt Shale Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Theropoda Indet.Indeterminate

Pterosaurs

Pterosaurs of the Lealt Shale Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Dearc [5] D. sgiathanachA angustinaripterin rhamphorhynchid
Dearc restoration.jpg

See also

Footnotes

  1. Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607.
  2. Young, Chloe M. E.; Hendrickx, Christophe; Challands, Thomas J.; Foffa, Davide; Ross, Dugald A.; Butler, Ian B.; Brusatte, Stephen L. (May 2019). "New theropod dinosaur teeth from the Middle Jurassic of the Isle of Skye, Scotland". Scottish Journal of Geology. 55 (1): 7–19. doi:10.1144/sjg2018-020. hdl: 20.500.11820/063549bc-2a00-4ddc-bcf6-a1bc2f872c26 . ISSN   0036-9276. S2CID   134102042.
  3. dePolo, Paige E.; Brusatte, Stephen L.; Challands, Thomas J.; Foffa, Davide; Wilkinson, Mark; Clark, Neil D. L.; Hoad, Jon; Pereira, Paulo Victor Luiz Gomes da Costa; Ross, Dugald A.; Wade, Thomas J. (11 March 2020). Fiorillo, Anthony R. (ed.). "Novel track morphotypes from new tracksites indicate increased Middle Jurassic dinosaur diversity on the Isle of Skye, Scotland". PLOS ONE. 15 (3): e0229640. doi: 10.1371/journal.pone.0229640 . ISSN   1932-6203. PMC   7065758 .
  4. "Lealt Shale Formation". BGS Lexicon of Named Rock Units. Retrieved 22 February 2022.
  5. Jagielska, N.; O'Sullivan, M.; Funston, G. F.; Butler, I. B.; Challands, T. J.; Clark, N. D. L.; Fraser, N. C.; Penny, A.; Ross, D. A.; Wilkinson, M.; Brusatte, S. L. (2022). "A skeleton from the Middle Jurassic of Scotland illuminates an earlier origin of large pterosaurs". Current Biology . 32 (6): 1446–1453.e4. Bibcode:2022CBio...32E1446J. doi: 10.1016/j.cub.2022.01.073 . hdl: 10023/27028 . PMID   35196508. S2CID   247013664.

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References