CORE UNIT: PATTERNS AND PROCESSES IN THE PHYSICAL ENVIRONMENT
V-shaped valley
River Fig. 21 A V-shaped valley near Kinsale, County Cork and contour pattern of a V-shaped valley
2. Interlocking spurs Main processes: Hydraulic action, abrasion, solution, vertical erosion, winding streams. Example: Upper stage of the River Glen, County Down Interlocking spurs are landforms of river erosion. They are hills or ridges of land
(spurs) around which the river winds. If you look up a river valley, these spurs or hills seem to overlap across each other (interlock) blocking the view of the river. Viewed fromabove you can clearly see the river winding around these hills/spurs.
IN DEPTH – Interlocking spurs
Interlocking spurs are found in the young stage of the river’s lifecycle. As youthful rivers are small they do not have the energy to remove large obstacles in their path. Young rivers do not carry a large load so abrasion is limited. Hydraulic action is the dominant erosion process.As the river flows, itwinds around the hard patches of rock found along its course. These irregularities in the channel further deflect the river from side to side, so that it changes from a relatively straight to a winding course. The current is stronger on the outside of a bend as hydraulic action and abrasion are
concentrated here and the bends become more developed. This erosion of the river valley leaves parts of the valley sides projecting as small hills or spurs into the bends in the river channel. Eventually in the middle and lower stages the river becomes larger and more
powerful by the addition of water fromtributaries and removes the interlocking spurs completely.