Scalby Formation
{{Short description|Geological formation in England}}
{{Use dmy dates|date=April 2022}}
{{Infobox rockunit
| name = Scalby Formation
| period = Bathonian
| age = {{fossilrange|Bathonian|Bathonian|Bathonian}}
| image = Scalby_Beck_(geograph_2696982).jpg
| imagesize =
| caption = exposure of the Scalby Formation near Scalby, North Yorkshire
| type = Geological formation
| prilithology = *Moor Grit Member - Sandstone
| otherlithology = *Moor Grit Member - Mudstone, Siltstone
- Long Nab Member - Sandstone
| unitof = Ravenscar Group
| subunits = Moor Grit Member, Long Nab Member
| underlies = Cornbrash Formation, Osgodby Formation
| overlies = Scarborough Formation
| thickness = up to {{Convert|60|m|ft|-1}}
| area =
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| region = Europe
| country = United Kingdom
| extent = North Yorkshire
| namedfor = Scalby, North Yorkshire
| namedby =
| year_ts =
| location_ts = Scalby Cliff
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The Scalby Formation is a geological formation in England. Part of the Ravenscar Group, it was deposited in the Bathonian stage of the Middle Jurassic. The lower Moor Grit Member has a lithology consisting of medium to coarse grained cross bedded sandstone, with thin beds of mudstone and siltstone, while the upper Long Nab Member has a lithology consisting of predominantly laminated mudstone and siltstone, with fine to medium grained planar and cross stratified sandstones.{{cite web |url= https://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=SCY|title= Scalby Formation|last= |first= |date= |website= |publisher= British Geological Survey|work = BGS Lexicon of Named Rock Units|access-date= 7 August 2018|quote=}} The formation is thought to have accumulated on a floodplain,{{Cite journal |last1=Slater |first1=Sam M. |last2=Wellman |first2=Charles H. |last3=Romano |first3=Michael |last4=Vajda |first4=Vivi |date=March 2018 |title=Dinosaur-plant interactions within a Middle Jurassic ecosystem—palynology of the Burniston Bay dinosaur footprint locality, Yorkshire, UK |url=http://link.springer.com/10.1007/s12549-017-0309-9 |journal=Palaeobiodiversity and Palaeoenvironments |language=en |volume=98 |issue=1 |pages=139–151 |bibcode=2018PdPe...98..139S |doi=10.1007/s12549-017-0309-9 |issn=1867-1594}} with a seasonally dry climate.{{Cite journal |last1=Morgans |first1=Helen S. |last2=Hesselbo |first2=Stephen P. |last3=Spicer |first3=Robert A. |date=June 1999 |title=The Seasonal Climate of the Early-Middle Jurassic, Cleveland Basin, England |url=https://pubs.geoscienceworld.org/palaios/article/14/3/261-272/99727 |journal=PALAIOS |volume=14 |issue=3 |pages=261 |bibcode=1999Palai..14..261M |doi=10.2307/3515438 |jstor=3515438|url-access=subscription }}
Fossilized dinosaur tracks have been found in the Scalby Formation; these include a recently discovered footprint from a large theropod, probably a megalosaurid. The track is from the Long Nab Member, and has been assigned to the ichnogenus Megalosauripus.{{Cite journal |last=Hudson, J.G. |last2=Romano, M. |last3=Lomax, D.R. |last4=Taylor, R. |last5=Woods, M. |date=16 February 2023 |title=A new giant theropod dinosaur track from the Middle Jurassic of the Cleveland Basin, Yorkshire, UK |url=https://www.lyellcollection.org/doi/10.1144/pygs2022-008 |journal=Proceedings of the Yorkshire Geological Society |volume=64 |issue=3 |via=Lyell Collection}}
Like other members of the Ravenscar Group, the formation is well known for its plant fossils (including pollen), which consist of Ginkgoales (including the living genus Ginkgo), Czekanowskiales, bennettitaleans, cheirolepidacean and araucarian conifers, ferns, lycophytes, and seed ferns including Caytoniales.{{Cite journal |last1=Slater |first1=Sam M. |last2=Wellman |first2=Charles H. |date=March 2016 |editor-last=Lomax |editor-first=Barry |title=Middle Jurassic vegetation dynamics based on quantitative analysis of spore/pollen assemblages from the Ravenscar Group, North Yorkshire, UK |url=https://onlinelibrary.wiley.com/doi/10.1111/pala.12229 |journal=Palaeontology |language=en |volume=59 |issue=2 |pages=305–328 |bibcode=2016Palgy..59..305S |doi=10.1111/pala.12229 |issn=0031-0239|doi-access=free }}