The Ichthyosaur has been found in many geological formations like theAgardhfjellet Formation in Norway that spans several eras.
Agardhfjellet Formation The Agardhfjellet Formation is a geologic formation in Svalbard, Norway. It preserves fossils dating back to the Oxfordian to Berriasian stages, spanning the Late Jurassic-Early Cretaceous boundary. Antimonio Formation Besano Formation Blue Lias Clearwater Formation Favret Formation (Fossil Hill Member) Franciscan Formation Guanling Formation Hosselkus Limestone Jialingjiang Formation Katrol Formation Khao Thong Hill Kimmeridge Clay Loon River Formation Los Molles Formation Lower Greensand Luning Formation Muschelkalk Nanlinghu formation Nyalam Opalinuston Formation Osawa Formation (upper) Oxford Clay Paja Formation Pardonet Formation Posidonia Shale Prida Formation (Fossil Hill Member) Ringnes Formation Solnhofen Limestone Speeton Clay Sticky Keep Formation Strawberry Bank, Ilminster Sulphur Mountain Formation Sundance Formation Tschermakfjellet Formation Vaca Muerta Xiaowa Formation 
