A deposit with large clasts at the base that become finer upwards is known as a _____.
A)ripple marks
B)mudcracks
C)oxidation
D)graded bed
E)calcareous ooze

Question

Quizplus · Accepted Answer

A graded bed is a sedimentary deposit with large clasts at the base that became finer upwards. This indicates that the sediment was deposited by a rapidly-moving current that first transported the larger particles and then gradually slowed down, allowing the smaller particles to settle on top of the larger ones, resulting in a graded bed. Ripple marks (A) and mudcracks (B) are features formed on the surface of sediment and indicate conditions of erosion and exposure. Oxidation (C) is a chemical process that can occur in sediment, but it does not describe the structure or composition of a deposit. Calcareous ooze (E) is a type of sediment that is composed of the remains of microscopic marine organisms and does not necessarily have a graded bed structure.

A Deposit with Large Clasts at the Base That Become