Exposures of the Santa Cruz formation in the cliffs above the Atlantic are inaccessible. The best fossils come from the beaches between high and low tide levels.
The fossil-bearing beds exposed at sea level dip about 3 degrees on a southward strike so that at low tide (when tide is about 7 meters) the same bedding plane is exposed to a breadth of 500-700 meters to seaward. It is then possible to collect large numbers of fossils of similar geological age; most of the fossils from one locality are analytically indistinguishable from one another in age.