how old are the deltas?
most are very young geological features – some only a few 100s years old young deltas controlled in part by sea level… older deltas some rivers have built their deltas on top of older deltas built up during previous interglacial periods; e.g. Mississippi delta is underlain by deltas 10s of M years old forming different lobes (new lobes are formed whenever the location of the river mouth changes); present lobe of the Mississippi delta is 600 years old environments of the delta depends on the interaction between the river’s sediment flow and distribution and the wave and tidal currents; as water flows from the river’s mouth, its velocity decreases and it loses its capacity to carry sediment – sediments accumulate in the river mouth area and the river divides into distributary channels Huang (yellow river), China: river with the greatest sediment load delta plain: landward and very flat part of the delta natural levee: when a distributary channel overflows its banks, the coarser sandy s
