Final answer:
The process through which rocks are broken down into smaller fragments is called weathering, which is distinct from erosion, transportation, and lithification.
Step-by-step explanation:
The sedimentary process by which rocks are broken down into smaller fragments or detritus is known as weathering. This process can be either mechanical or chemical and leads to the formation of sediment, which is the raw material that eventually forms sedimentary rocks. After weathering, the particles produced are typically transported by elements like water, wind, or ice, in a process called erosion. The transportation of these particles is a key stage that shapes various landscapes on the Earth's surface. Following transportation, sediments are then deposited, and over time, they undergo lithification, a process involving compaction and cementation that transforms loose sediments into solid sedimentary rock layers.