Final answer:
Aggregate is classified by size and gradation using a series of sieves. Sieves sort different sizes of sediment, providing detailed grain size distribution, essential for understanding geological processes and sediment characteristics.
Step-by-step explanation:
Aggregate is classified by size and gradation using a series of sieves.
In geosciences and engineering, the classification of aggregate or sediment involves measuring and comparing the particle size distribution. This can be exceptionally important when analyzing sedimentary rocks or evaluating a potential construction material. Traditional methods use mechanical sieves to separate particles into size fractions. Sieving provides a quantitative way to measure grain sizes and their distribution within a sediment sample. For more precise laboratory measurements, geologists might use computerized particle sizers, but mechanical sieves are common in both field and lab work.
Grain size analysis is critical as it can reveal considerable information about the sediment, such as the transport and depositional history. Moreover, graded bedding, a sedimentary structure observable in a sedimentary bed, reflects a change in energy levels of the depositional environment over time.