The Long profile of a river The River

The Long profile of a river The River Severn River Conwy

The Long profile of a river

http: //www. bbc. co. uk/learningzone /clips/the-river-severn-uppercourse/3076. html http: //www. bbc. co. uk/learningzone/clips/theriver-severn-lower-course-andestuary/3077. html http: //www. bbc. co. uk/learningzone/ clips/the-course-of-the-river-severnfrom-source-to-sea/340. html https: //www. youtube. com/watch? v=n. NAYe 8 v p 3 a. Q

River Conwy • http: //www. bbc. co. uk/learningzone/clips/wat erfalls-and-gorges-erosion-anddeposition/3239. html • V shaped valley • http: //www. bbc. co. uk/learningzone/clips/rive rs-weathering-erosion-and-corrasion/400. html

Why does the cross profile of a river change shape as we travel down the long profile? • In the upper course the river has lots of energy and is eroding vertically, this creates a deep Vshaped valley. As we move further from the source into the middle and lower section the river is closer to sea level, as such has less energy for vertical erosion and erodes laterally instead. This makes the valley wider, weathering further flattens the valley sides creating a wide and flat valley.

Why is the sediment in a river smaller towards the mouth than at the source? • As the river gets towards the mouth the material in the river has been carried further from the upper course. As it has been in the water for longer it has been eroded by processes such as attrition, meaning it has collided with other particles breaking bits off to make them smoother and smaller.