The diagrams illustrate the process of forming sedimentary rock in coastal area.
Overall, there are two main stages in the process of producing rock formed from deposited materials. The process starts with rainfalls on the mountainside, the erosion of rock and fissure, and finishes with either sandstone or mudstone formation.
The process begins with rain falling on the mountainside, filling fissures and cracks with water. At some point, the water starts to freeze and expand, causing breaks of the fissures and cracks. Then, the dislodged rocks and stones fall into the river. During this period, the rocks and stones are broken and reduced into small pebbles and grains of sand. Afterwards, these stones move downstream until they reach the lowest water level.
The last two diagrams show the process of forming sedimentary rock. Initially, these pebbles settle evenly under the water level, where they mix with other materials like sand and cement. Due to high and low tides, this sediment accumulates closer to the mountain base over time and creates the coasts.