Depositional environments are specific settings where sediments accumulate over time. These environments can include rivers, lakes, oceans, and deserts, each characterized by unique conditions that influence the type of sediment deposited. For example, river environments typically carry sand and gravel, while ocean environments may deposit finer materials like silt and clay. The study of depositional environments helps geologists understand Earth's history and the processes that shape landscapes. By analyzing sediment characteristics, such as grain size and composition, scientists can reconstruct past environments and predict how they might change in the future. This knowledge is essential for fields like paleontology and petroleum geology.