Berkeley, Sunday, October 7, 2018 3:54 PM
Since we have lived in a built environment, it is harder to realize about that the soil is on continuous movement. However, it moves very slowly, it geological times.
The landscape is shaped by several force drivers such as: water flow and rainfall, wind velocity, earthquakes, gravity, chemical processes, and resultant driving forces for the continous Earth spinning.
Sediments are generated by those process. I can generalize sediment to any size of grain material regardless its composition. Then I call sediment boulders, pebbles, gravel, sand, clay, silt, and soil in general.
When erosion of the land happen, we start looking gullies, which are channels in the hills. Those will become tributaries from a larger river, which might already converted a mountainous areas into a valley over thousands, if not millions of years.
Mountains and rivers keep shaping.
Where the continent reach the ocean, by discharging water, sediments and aquatic life on it, its name is delta. Delta has been built naturally over thousands of years by sediment deposition.