The Long Profile of a River, and the Physical diversity of the UK.

UK Upland: Describe the mountains of scotland and northern ireland.

Scotland: the North West highlands are separated from the Grampians to the south by glen more. This lowland area contains many lochs (eg Loch Ness). The mountains form a plateau, which has been dissected by steep sided glaciated valleys.south of the grampians is the 80km wide rift valley of the central lowlands.

Northern Ireland: The Antrim plateau is located in north-east ireland, and is made of basalt. Along the coast, this rock has weathered to form the hexagonal blocks of the giant’s Causeway.

UK Upland: Describe the Cumbrian Mountains and the Pennines.

Cumbrian Mountains: Are located between the Solway Firth to the north and Morecombe Bay t the south. This is commonly known as the Lake District. Rivers and glaciated ribbon lakes radiate from the centre of the 900m dome. Shap Fell ridge links the Lake District with the Pennines.

The Pennines: This 600m high plateau runs from the River Tyne in the north to the northern edge of the Midlands in the south. The Pennines form a West-east watershed, with most rivers eastwards. The River Trent flows to the north of the Pennines.

UK Upland: Describe the Cambrian mountains of Wales and Moorlands of the South West Peninsula.

Cambrian mountains of Wales: are a dissected plateau that has rivers radiating out from its centre. The major rivers of the Severn and Wye have their source here. They then flow in a large loop to the estuary in the English channel.

Moorland of the South West Peninsula: the granite moors of Dartmoor and Bodmin Moor rise to over 600m. In places, tors (bare rock pillars) rise above poorly drained moors. The rivers Taymar and Exe start close to the north coast of the peninsula.

UK Lowlands: describe the Scarps and Vales and the Landscapes of the UK.

Scarps and Vales: central and southern England has low-lying clay vales, alternating with chalk ridges and distinctive steep scarp and gentle slopes. Examples of the chalk ridges include the north and south downs. Limestone hills include the cotswolds and mendips. The clay vales stretches across Wiltshire and oxforshire. Thames has its source in the cotswolds and flows southeast through the low lying London basin into the north sea.

Landscapes of the UK: Areas characterized by the action and interaction of natural and human factors.

UK Lowlands: Describe northeast England and the Fens and East Anglia.

Northeast England: The extensive river system of the Derwent, Ouse, Wharfand trent, which drain into the hUmber Estuary.

The Fens and East Anglia: the most extensive areas of lowland are found in East Anglia. Here, much of the land is below sea level, where the rivers nene and the great ouse are found.

The Long Profile: describe the Upper Course.

• Mostly vertical erosion

• Steep sided

• Interlocking spurs

• Rapids and waterfalls

• V-shaped valleys

• Slower moving water due to friction

• Has large material not yet eroded down.

• Has a drainage basin

The Long Profile: describe the Middle Course.

• Flatter

• Wider due to tributaries joining

• Smaller material

• Lateral erosion taking over

• Transportation and erosion

• Has meanders and ox-bow lakes.

The Long Profile: describe the Lower Course.

• Very flat and wide

• Fine material

• A large load

• More depositon

• Faster flowing

• Has Delta and a flood plain.

What is the source?

The start of the river

What is the watershed?

The boundary between two drainage basins.

What is the drainage basin (/catchment area)?

The area drained by a river.

What is a tributary?

A small stream joining the main river.

What is the confluence?

The point at which a tributary joins a river.

What is a meander?

A bend in the river.

What is an ox-bow lake?

A cut-off meander.

What is a flood plain?

Flat,fertile land next to the river.

What is delta?

The material deposited.

What is the mouth of a river?

The end of a river.

What does the long profile show?

The gradient of a river as it travels from source to mouth.

What is the base level? Why does a river want to achieve this?

A river will try to achieve a smooth curve in order to reach its ‘base level’ - basically sea level.

This is called the graded profile.

What is the discharge of a river? Include its measurement and formula.

The volume of water passing through a given point at a given time on a river.

Its measured in cubic metres per second (cumecs).

Discharge= velocity x cross-sectional area.

What happens to discharge downstream?

Discharge increases with distance downstream because the tributaries join, bringing more water, and add to the volume of water in the main river.

How does average velocity of a river change with distance downstream?

Average velocity of a river increases with distance downstream.

Velocity is determined by several factors, such as gradient. The most important one is the amount of water in contact with the bed and banks of the river channel. The more there is, the more friction, and the slower it will go.

Therefore in the upper course, where there's little water, there’s more friction, and the slower it will be.

As you move more downstream, and more water’s added, and the channel gets a little wider and deeper, there will be less water in contact with the bed and banks, and the river will speed up with distance downstream.

What is a cross profile, channel cross profile, and valley cross profile?

Cross profile - a section from the side across a river channel and / or valley.

Channel cross profile - only the river itself

Valley cross profile - the valley floor and the slopes up the side of the valley.

Describe the process of erosion, transport and deposition in the upper course of a river.

Mostly vertical erosion by hydraulic action.

Transport mostly via traction. Large boulders are moved.

Large boulders are deposited.

The upper course is set in a high landscape of relief. The long profile starts at its source. Trickles begin to merge to form a single channel which flows down a steep gradient. The steep descent gives the river more potential energy. In places, there may be waterfalls or rapids.

Describe the process of erosion, transport and deposition in the middle course of a river.

Less vertical erosion, more lateral erosion. Much attrition and abrasion, some solution.

Transported mostly via suspension, but traction increases. Load becomes smaller and less angular.

More deposition, especially on the inside bend of meanders.

Middle course if further downstream in a more hilly than mountainous relief. Discharge increases as the channel is deeper, and the volume of water increases from tributaries. The river’s energy results in less vertical erosion and more lateral erosion at meanders. As vertical erosion reduces, the gradient of the long profile becomes concave.

Describe the process of erosion, transport and deposition in the lower course of a river.

Very little erosion, only lateral.

Transport via mostly suspension and solution. Very small particles but a high quantity of load.

Deposition now the main fluvial process. Fine material now deposited.

The lower course is the section closest to the river mouth, where surrounding land is low-lying. Only lateral erosion which occurs at meanders. Lack of vertical erosion means gradient is almost flat.