Which type of sediment settles the fastest?

Gravel settles the fastest due to its larger particle size compared to the other types of sediment. The settling velocity of particles in a fluid is influenced by their mass and shape, with larger, denser particles typically experiencing less resistance from the fluid they are settling through. In this case, gravel has a higher density and a larger size than clay, silt, or sand, allowing it to overcome the drag force exerted by the water more efficiently and settle quickly to the bottom.

In contrast, clay and silt are much finer and will remain suspended in water for longer periods due to their smaller size and lower settling rates. Sand, while coarser than clay and silt, still has a slower settling rate than gravel because of its smaller size compared to gravel particles. This dynamic underscores the importance of understanding sediment characteristics in cavern diving, as it impacts visibility and environmental conditions.