Explore the findings of a large-scale flume experiment investigating combined-flow ripple development on mixed sand-clay beds in this 59-minute video. Discover the threshold bed clay content that controls the generation of two distinct types of equilibrium ripples: large ripples comparable to clean-sand counterparts and smaller, flatter ripples reflecting strong bed cohesion. Learn about the clay loss observed at deeper layers below large equilibrium ripples due to clay winnowing under combined flow, and its potential impact on rippled bed stability. Gain insights into the complex interactions between clay content, ripple formation, and sediment transport in mixed substrate environments.