Final answer:
Turbidity currents are a geologic indicator of rapid deposition, as they transport and deposit sediment downslope. The coarsest particles are found at the bottom of the sediment bed, and the smallest particles are found at the top. Structures such as flute casts can also provide information about the direction of flow.
Step-by-step explanation:
Turbidity currents are a geologic indicator of rapid deposition. Turbidity currents are underwater avalanches of sediment that move downslope, carrying grains sorted by density. As they flow, they deposit sediment in a graded bedding pattern, with the coarsest particles at the bottom of the bed and the smallest at the top. These currents also create structures such as flute casts, which indicate the direction of flow.