List of plesiosaur-bearing stratigraphic units

Group or Formation Period Country Notes Adaffa Formation Cretaceous Agardhfjellet FormationHurum, J.H., Nakrem, H.A., Hammer, Ø, Knutsen, E. M., Druckenmiller, P.S., Hryniewicz, K. & Novis, L.K.: An Arctic Lagerstätte – the Slotts- møya Member of the Agardhfjellet Formation (Upper Jurassic – Lower Cretaceous) of Spitsbergen. Norwegian Journal of Geology, Vol 92, pp. 55-64. Trondheim 2012, ISSN 029-196X. Jurassic Agrio Formation Cretaceous Akrabou Formation Cretaceous Allaru Mudstone Formation Cretaceous Allen Formation Cretaceous Alum Shale Formation Jurassic Ampthill Clay Formation Jurassic Ancholme Group/Kimmeridge Clay Formation Jurassic Ancholme Group/Oxford Clay Formation Jurassic Arauco Group/Quiriquina Formation Cretaceous Arcillas de Morella Formation Cretaceous Arctic Red Formation Cretaceous Argiles de Châtillon Formation Jurassic Argiles de Montaubert Formation Jurassic Argille Varicolori Formation Cretaceous Artemesia Formation Jurassic Artoles Formation Cretaceous Ashville Formation Cretaceous Balqa Group/Phosphorite Unit Formation Cretaceous Barrow Formation Cretaceous Barrow Group/Birdrong Sandstone Formation Cretaceous Bearpaw Formation Cretaceous Bearpaw Shale Formation Cretaceous Belly River Formation Cretaceous Belly River Group/Dinosaur Park Formation Cretaceous Bissekty Formation Cretaceous Blue Lias Formation Jurassic Braunjura Group/Braunjura alpha & Braunjura beta Formation Jurassic Bückeberg Formation Cretaceous Calcaire de Caen Formation Jurassic Calcaire à Bélemnites Formation Jurassic Calcaires de MoulinFormation Jurassic Calcaires à Spatangues Formation Cretaceous Calcareous Grit Formation Jurassic Carlile Shale Formation Cretaceous Chalk Formation Cretaceous Chalk Group/"Upper Chalk" Formation Cretaceous Chalk Group/Lower Chalk Formation Cretaceous Chalk Group/LowerFormation Cretaceous Chalk Group/LowerFormation Cretaceous Champion Bay Group/Colalura Sandstone Formation Jurassic Charmouth Mudstone Formation Jurassic Chico Formation Cretaceous Chico Group/Moreno Formation Cretaceous Clearwater Formation Cretaceous Colorado Group/Belle Fourche Formation Cretaceous Colorado Group/Carlile Shale Formation Cretaceous Colorado Group/Graneros Shale Formation Cretaceous Colorado Group/Greenhorn Limestone Formation Cretaceous Colorado Group/Niobrara Formation Cretaceous Conway Formation Cretaceous Conway Siltstone Formation Cretaceous Coon Creek Formation Cretaceous Coral Rag Formation Jurassic Corallian Oolite Formation Jurassic Corallian Group/Coral Rag Formation Jurassic Corallian Group/Kingston Formation Jurassic Couche III Formation Cretaceous Cuyo Group/Los Molles Formation Jurassic Dinosaur Park Formation Cretaceous Dorotea Formation Cretaceous Duwi Formation Cretaceous Eagle Ford Formation Cretaceous Eagle Ford Group/Britton Formation Cretaceous Estratos de Quebrada Municipalidad Formation Cretaceous Eutaw Formation Cretaceous Evergreen Formation Jurassic Favel Formation Cretaceous Fernie Formation Jurassic Frontier Formation Cretaceous Futaba Group/Ashizawa Formation Cretaceous Futaba Group/Tamayama Formation Cretaceous Great Estuarine Formation Jurassic Great Estuarine Series Group/Estheria Shales Formation Jurassic Great Estuarine Group/Lealt Shale Formation Jurassic Great Oolite Formation Jurassic Gres de Mortinsart Formation Triassic Grès de Infralias Formation Triassic Grünsandstein Formation Cretaceous Hailey Shales Formation Cretaceous Hasle Formation Jurassic Hastings Formation Cretaceous Hastings Beds Group/Wadhurst Clay Formation Cretaceous Hell Creek Formation Cretaceous Hiccles Cove Formation Jurassic Hornerstown Formation Cretaceous Isachsen Formation Cretaceous Itapecuru Formation Cretaceous Alcântara Formation Cretaceous Jagua Formation Jurassic Jagüel Formation Cretaceous Judith River Formation Cretaceous Kajlâka Formation Cretaceous Kangauz Formation Cretaceous Kanguk Formation Cretaceous Katiki Formation Cretaceous Katrol Formation Jurassic Kimmeridge Clay Formation Jurassic Kunrade Formation Cretaceous La Cabana Formation Cretaceous La Caja Formation Jurassic La Casita Formation Jurassic La Colonia Formation Cretaceous La Luna Formation Cretaceous Lajas Formation Jurassic Lake Waco Formation Cretaceous Laramie Formation Cretaceous Lias Formation Jurassic Lias Formation Jurassic Lias Group/Blue Lias Formation Jurassic Lias Group/Charmouth Mudstone Formation Jurassic Lias Group/Dyrham Formation Jurassic Lias Group/Marlstone Rock Formation Jurassic Lias Group/Scunthorpe Mudstone Formation Triassic Lias Group/Waterloo Mudstone Formation Jurassic Lias Group/Whitby Mudstone Formation Jurassic López de Bertodano Formation Cretaceous Los Alamitos Formation Cretaceous Lower Chalk Group/Cambridge Greensand Formation Cretaceous Lower Green Sand Formation Cretaceous Lower Greensand Group/Faringdon Sand Formation Cretaceous Lower Greensand Group/Hythe Formation Cretaceous Luxembourg Sandstone Formation Jurassic López de Bertodano Formation Cretaceous Maaree Group/Bulldog Shale Formation Cretaceous Maastricht Formation Cretaceous Malargue Group/Roca Formation Cretaceous Malargüe Formation Cretaceous Malargüe Group/Allen Formation Cretaceous Malargüe Group/Loncoche Formation Cretaceous Mannville Group/Clearwater Formation Cretaceous Marambio Group/Snow Hill Island Formation Cretaceous Marnes de Dives Formation Jurassic Marnes de Gravelotte (=La Gravclotte Marls) Formation Jurassic Marree Group/Bulldog Shale Formation Cretaceous Mata Amarilla Formation Cretaceous Mata Group/Tahora Formation Cretaceous Melovatka Formation Cretaceous Mesaverde Formation Cretaceous Middle Keuper Group/Knollenmergel Formation Triassic Middle Keuper Group/Trossingen Formation Triassic Middle Yezo Formation Cretaceous Middle Yezo Group/Chenaibo Formation Cretaceous Molecap Greensand Cretaceous Monmouth Group/Navesink Formation Cretaceous Mont Formation Jurassic Montana Group/Pierre Shale Formation Cretaceous Moreno Formation Cretaceous Navesink Formation Cretaceous Nekum Formation Cretaceous Neuquén Group/Anacleto Formation Cretaceous Newcastle Formation Triassic Niobrara Formation Cretaceous Otway Group/Eumeralla Formation Cretaceous Oxford Clay Formation Jurassic Paja Formation Cretaceous Paso del Sapo Formation Cretaceous Penarth Group/Westbury Formation Triassic Penarth Group/White Lias Formation Triassic Pender Formation Cretaceous Pernarth Group/Westbury Formation Triassic Pierre Shale Formation Cretaceous Point Lookout Formation Cretaceous Portland Oolite Formation Jurassic Portland Group/Portland Stone Formation Jurassic Posidonia Shale Jurassic Purbeck Formation Cretaceous, Jurassic Purbeck Group/Lulworth Formation Cretaceous, Jurassic Puskwaskau Formation Cretaceous Querecual Formation Cretaceous Quiriquina Formation Cretaceous Raritan Formation Cretaceous Razorback Beds Formation Jurassic Rio del Lago Formation Triassic Rodiles Formation Jurassic Rolling Downs Group/Griman Creek Formation Cretaceous Rolling Downs Group/Toolebuc Formation Cretaceous Rolling Downs Group/Wallumbilla Formation Cretaceous Rolling Downs Group/Winton Formation Cretaceous Rosablanca Formation Cretaceous Rosso Ammonitico Veronese Formation Jurassic Rybushka Formation Cretaceous Sables de Glos Formation Jurassic Saint Formation Cretaceous Santa Marta Formation Cretaceous Savel'evsk oil shales Formation Jurassic Scalpa Sandstone Formation Jurassic Selborne Group/Upper Greensand Formation Cretaceous Selma Group/Mooreville Chalk Formation Cretaceous Severn Formation Cretaceous Snow Hill Island Formation Cretaceous Speeton Clay Formation Cretaceous Spilsby Sandstone Formation Jurassic Staffin Bay Formation Jurassic Strzelecki Group/Wonthaggi Formation Cretaceous Sundance Formation Jurassic São Gião Formation Jurassic Tadi Beds Formation Cretaceous Taylor Marl' Formation Cretaceous Tessé Sandstones Formation Jurassic Thermopolis Shale Formation Cretaceous Tioriori Group/Takatika Grit Formation Cretaceous Toolebuc Formation Cretaceous Tropic Shale Formation Cretaceous Trossingen Formation Triassic Tugulu Group/Lianmugin Formation Cretaceous Uitenhage series Formation Cretaceous Uitenhage Group/Sundays River Formation Cretaceous Upper Chalk Formation Cretaceous Upper Gondwana Group/Umia Formation Jurassic Upper Greensand Formation Cretaceous Upper Keuper Group/Exter Formation Triassic Vaca Muerta Formation Cretaceous, Jurassic Vermillion River Formation Cretaceous Wallumbilla Formation Cretaceous Waterloo Formation Jurassic Weald Clay Group/Upper Weald Clay Formation Cretaceous Wealden Group/Tunbridge Wells Sand Formation Cretaceous Wealden Group/Vectis Formation Cretaceous Whitby Mudstone Formation Jurassic Wilczek Formation Triassic Wilgunya Group/Toolebuc Formation Cretaceous Wilhelmøya Formation Triassic Xiashaximiao Formation Jurassic Ziliujing Formation Jurassic

References