Detailed logging of ichnological variations within parasequences of several Cretaceous (Upper Turonian) delta complexes from Wyoming and Utah are correlated with inferred short and long-term changes in depositional processes. These changes reflect various proportions of river, flood, wave, storm, and tide influences. Event beds, such as storm and river-flood deposits, tend to show low BI (Bioturbation Index) values of 0-2, owing to high accumulation rates, although this also depends on event frequencies. Upper surfaces of individual storm/river-flood beds may show BI values of 4-5, reflecting the transition to longer-lived fair-weather conditions. Fair-weather waves facilitate persistent agitation near the bed, buffering environmental stresses. Therefore, wave-dominated deposits that are not affected by storms yield climax communities with robust and diverse ichnofacies signatures reflecting “uniform and high” BI trend with values that average 4.