GEOLOGY

Detailed explanation-1: -Bedding in which the particle sizes become progressively heavier and coarser towards the bottom layers is called graded bedding.

Detailed explanation-2: -“Normal” graded beds are coarse at the bottom and become finer toward the top, a product of deposition from a slowing current (Figure 6.22). Some graded beds are reversed (coarser at the top), and this normally results from deposition by a fast-moving debris flow (see Chapter 15).

Detailed explanation-3: -Graded Bedding A type of bedding in which each layer is characterized by a progressive decrease in grain size from the bottom to the top of the bed. Graded bedding is caused by the differential settling by size and weight of suspended particles in water.

Detailed explanation-4: -Detrital sedimentary graded beds are formed from erosional, depositional, and weathering forces. Graded beds formed from detrital materials are generally composed of sand, and clay. After lithification, shale, siltstone, and sandstone are formed from the detrital deposits.

Detailed explanation-5: -In sedimentary rock: Types. Graded bedding simply identifies strata that grade upward from coarse-textured clastic sediment at their base to finer-textured materials at the top (Figure 3). The stratification may be sharply marked so that one layer is set off visibly from those above and beneath it.