Deposition and interpretation of long, narrow sandbodies underlain by a basinwide erosion surface; Cardium Formation, Cretaceous Western Interior Seaway, Alberta, Canada

Sand bodies of the Cardium alloformation (Burnstick allomember) occur in three parallel linear trends in the Garrington, Caroline-Crossfield and Lochend oilfields. They are extremely long (up to 100 km), straight and narrow (up to 4 km) and are encased in marine mudstones, suggesting their former interpretation as "offshore bars". Our study of 189 cores and over 800 resistivity well logs shows that, below the Burnstick, the Hornbeck allomember …