During which geological process do sediments accumulate and form sedimentary rocks?

The process through which sediments accumulate and form sedimentary rocks is compaction. This occurs after sediments, which can include fragments of rocks, minerals, and organic material, are deposited in layers over time, typically in body of water or other environments conducive to sediment deposition. As layers build up, the weight of the overlying sediments compresses the deeper layers, driving water and air out from between the grains and causing the sediments to become more tightly packed together. This compaction, along with cementation, where minerals precipitate from water and bind the particles together, ultimately leads to the formation of sedimentary rocks.

While weathering, erosion, and metamorphism are important geological processes, they do not directly result in the accumulation and formation of sedimentary rocks. Weathering refers to the breakdown of rocks into smaller particles, erosion is the movement of these particles from one location to another, and metamorphism involves the transformation of existing rocks under heat and pressure, which leads to the formation of metamorphic rocks rather than sedimentary rocks.