antidunes are commonly observed in small streams that flow across beaches into the ocean. flume studies have shown that they can also occur in submarine environments beneath density flows like turbidity currents. antidunes produce sedimentary structures characteristic of their flow regime, which allow sedimentary geologists to understand past flow conditions. unlike low flow regime bedforms like dunes and ripples which generally produce downstream dipping cross stratification, antidunes produce a mixture of low-angle downstream and upstream dipping strata. while antidunes migrate upstream, upstream dipping cross-stratification is not indicative of antidunes or upper flow regime conditions.