13.4 Flooding and Earth Systems

River flooding is an important component of the Earth system. Some examples of its roles include:

• The creation of flood plains, which haven’t just fed people for millennia (as along the River Nile) but have nourished terrestrial ecosystems for almost 400 million years,
• The deposition of floodplain sedimentary rocks, which are host to some valuable resources, and have provided the materials for mountain building in the distant past, (Figure 13.4.1), and
• Movement of sediments far offshore via undersea slope failure. (An example is the January 2020 turbidity flow offshore from the Congo River in Africa. That event, which resulted in sediments being transported some 1200 km across the Atlantic seabed, happened only 10 days after the largest flood on the Congo River since the 1960s.)^[1]

Media Attribution

• Figure 13.4.1 Photo by Steven Earle, CC BY 4.0