Describe the landforms produced by rejuvenation.

Rejuvenation is the renewal of a rivers energy in response to a relative fall in base level. Base level is the same as current sea level and so a drop in base level can be caused by either eustatic sea level fall, isostatic rebound or tectonic activity.

There are three types of rejuvenation that I have learned about. One of them being incised meanders. Incised meanders are meanders which are particularly well developed and occur when a river’s base level has fallen giving the river a large amount of vertical erosion power, allowing it to downcut. There are two types of incised meanders, entrenched meanders and ingrown meanders. entrenched meanders are symmetrical and form when the river downcuts particularly quickly. Due to the speed which the river downcuts, there is little opportunity for lateral erosion to occur giving them their symmetrical shape. Ingrown meanders are asymmetrical. They form when the river downcuts at a less rapid pace, giving the river opportunity to erode laterally as well as vertically.

Another type of rejuvenation is river terraces. This is caused by a river eroding vertically into the former floodplain. If vertical erosion is rapid then paired terraces are formed either side of the channel. If vertical erosion is slower though, unpaired terraces form as the river is given opportunity to meander. River terraces are particularly useful for settlements as they provide flat areas above the present floodplain. Oxford, Cambridge and London all developed on the river terraces of the Isis, Cam and Thames respectively.

The final type of rejuvenation are knick points. Knick points appear on a rivers long profile and are, almost, like the steps down a river takes to reach the new base level. They relate to the extent to which a river has created a new profile in response to the new base