Professor A Seilacher of Tubingen University in Germany became a leading researcher on Cruziana in the 50s and 60s.
"Far from being random tracks they denote distinct depth related communities"
In order of increasing depth, he identified five zones based on an ichno-genus indicative of each one.
Glossifungites (Littoral)
Skolithos (Littoral)
Cruziana (Littoral down to wave base)
Zoophycos (Wave base to turbidite zone)
Nereites (turbidite zone)