Geometry and facies of stacked shallow-marine sandier upward sequences dissected by erosion surface, Cardium Formation, Willesden Green, Alberta

Willesden Green field is a long narrow sandstone body completely encased in marine mudstones. The field is Late Cretaceous (Turonian) in age, and contains as many as seven stacked, sandier upward sequences. The sequences are as much as 12 m (39.3 ft) thick, are stratigraphically distinct, and do not offlap systematically. Each sequence begins with marine bioturbated mudstones and passes upward into storm-dominated shallow marine sandstones. …