Topography and significance of a basinwide sequence-bounding erosion surface in the Cretaceous Cardium Formation, Alberta, Canada

The Cardium Formation (Turonian-Coniacian, Upper Cretaceous) of the Western Interior Seaway, Alberta, contains six marine sandier-upward successions bounded by seven basin-wide erosion surfaces. In the subsurface, erosion surface E5 is associated with major oil and gas fields and is penetrated by thousands of wells. A topographic map of E5, based on 6126 well logs and over 1100 measured cores, shows a series of subparallel elongate highs …