AAPG Bulletin, Vol.87, No.12, 1883-1909, 2003
Depositional remnants, part 2: examples from the Western Interior Cretaceous Basin of north America
The Western Interior Cretaceous basin contains numerous examples of depositional remnants (partially preserved portions of originally extensive depositional systems). Emphasis is placed on examples of accommodation remnants (i.e., a type of depositional remnant whose overlying erosion surface displays little relief and is preserved in an area of locally increased accommodation). Variations in spatial accommodation have been attributed to synsedimentary tectonics, erosional topography, differential compaction, and salt dissolution and are commonly associated with basement. faults. Remnants range in size from small to very large (basin-scale), and larger remnants commonly contain several smaller remnants. Remnants of shallow-marine sandstone encased in shale are an important and common type of stratigraphic trap. Failure to recognize a deposits as only remnants of depositional systems has led to misinterpretations of depositional environment and inaccurate paleo-geographic reconstructions.