Turners Falls Formation

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| name = Turners Falls Formation

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| type = Geological formation

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| region = {{Flag|Massachusetts}}

| country = {{Flag|United States}}

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| unitof = Newark Supergroup

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The Turners Falls Formation or Turners Falls Sandstone is an Early Jurassic geological formation in Massachusetts. Various reptile tracks and footprints are known from this strata. These include Antipus flexiloquus, which has been interpreted as belonging to a small quadrupedal reptile{{Cite journal|last=Coombs|first=Walter P.|date=1996|title=Redescription of the ichnospecies Antipus flexiloquus Hitchcock, from the Early Jurassic of the Connecticut Valley|url=https://www.cambridge.org/core/journals/journal-of-paleontology/article/redescription-of-the-ichnospecies-antipus-flexiloquus-hitchcock-from-the-early-jurassic-of-the-connecticut-valley/625149984DD34EC99C15FE8762690E66|journal=Journal of Paleontology|language=en|volume=70|issue=2|pages=327–331|doi=10.1017/S0022336000023416|s2cid=132779327 |issn=0022-3360}} or a pterosaur,{{Cite journal|last=Rainforth|first=E.C.|date=2006|title=Antipus flexiloquus – the earliest pterosaur tracks from North America?|journal=Geological Society of America Abstracts with Programs|volume=38|issue=2|pages=82}} though it is most likely a crocodylomorph.{{Cite journal|last1=Whyte|first1=M. A.|last2=Romano|first2=M.|date=2014-05-01|title=First record of the pterosaur footprint Pteraichnus from the Saltwick Formation (Aalenian) of the Cleveland Basin, Yorkshire, UK|url=https://pubs.geoscienceworld.org/pygs/article-abstract/60/1/19/322397/First-record-of-the-pterosaur-footprint|journal=Proceedings of the Yorkshire Geological Society|language=en|volume=60|issue=1|pages=19–27|doi=10.1144/pygs2014-338|issn=0044-0604}}

The formation is thought to represent the distal zones of three alluvial fans flowing west into a semiarid rift valley formed by a Mesozoic graben.{{Cite journal |last=Little |first=Richard D. |date=1982 |title=Lithified Armored Mud Balls of the Lower Jurassic Turners Falls Sandstone, North-Central Massachusetts |url=https://www.jstor.org/stable/30070759 |journal=The Journal of Geology |volume=90 |issue=2 |pages=203–207 |doi=10.1086/628665 |jstor=30070759 |s2cid=140571464 |issn=0022-1376}} These deposits represent the first infilling of the lowland that would one day become the Connecticut River Valley.

In addition to trace fossils, the Turners Falls Formation bears some of the most well-preserved specimens of armored mud balls in the world.{{Cite book |last=Little |first=R. D. |title=Exploring Franklin County, Western Massachusetts: Your Guide to Amazing Stories in Rocks & Landscapes. |publisher=Earth View LLC |year=2020 |location=Easthampton, MA}}