Here's a breakdown of how it works:

1. Sediment Deposition: Sediments, like sand, mud, or shells, are deposited in layers.

2. Burial and Compaction: As more sediment accumulates, the lower layers are buried under increasing weight. This pressure squeezes out water and air, causing the particles to pack closer together.

3. Cementation: Dissolved minerals in groundwater seep through the pores in the sediment. These minerals crystallize and act like glue, binding the sediment particles together.

This combined process of compaction and cementation results in the formation of solid rock.