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English: The Pierre Shale is a geologic formation or series in the Upper Cretaceous which occurs east of the Rocky Mountains from North Dakota to New Mexico.The Pierre Shale is of marine origin and was deposited in the Western Interior Seaway. It is correlative with other marine shales that occur farther west, such as the Bearpaw Shale, Mancos Shale and the Lewis Shale. It correlates with the Lea Park Formation in central Alberta.
Media in category "Pierre Shale"
The following 8 files are in this category, out of 8 total.