Fox Hills Formation is a Cretaceous geologic formation in the northwestern Great Plains of North America. It is present from Alberta on the north to Colorado in the south.
Dinosaur remains including those of the tyrannosaurs as well as those of non-dinosaur mosasaurs are among the fossils that have been recovered from the formation. 
Lithology [ edit ]
The Fox Hills Formation consists of marginal marine yellow
sandstone with shale interbeds. It was deposited as a regressive sequence during the retreat of the  Western Interior Seaway in Late Cretaceous time. It is underlain by the marine Pierre Shale in the US and by the equivalent Bearpaw Formation in Canada. The Fox Hills is overlain by continental sediments, called the Laramie Formation in the US.
See also [ edit ]
References [ edit ]
^ Getman, Myron RC (1994). "Occurrences of Mosasaur and other reptilian fossil remains from the Fox Hills Formation (Maastrichtian: late Cretaceous) of North Dakota". St. Lawrence University Dept. of Geology theses.
^ Lexicon of Canadian Geologic Units. "Fox Hills Formation" . Retrieved . 2010-02-01