Action of Running Water

Back to: GEOGRAPHY SS2

 

Welcome to class! 

In today’s class, we will be talking about the action of running water. Enjoy the class!

The Action of Running Water

RUNNING WATER

Running water is one of the most important agents of denudation. Rivers are involved in erosion transportation and deposition of materials.

TERMS ASSOCIATED WITH RIVERS

1. Source of a river: The source a river refers to where a river starts or begins, usually around highlands.
2. The course of a river: This refers to the path or channel through which the river flows.
3. The mouth of a river: This is where the river ends or where it enters into the sea, ocean or lake.
4. River basin or catchment area: It refers to all the areas drained by a river and its tributaries.
5. Watershed or water divide: It is the highland area which separates two or more rivers or two river basins. It is from the watershed that rivers take their sources.
6. River regime: This refers to the seasonal changes in the volume of water in a river in a year. It could be a single regime where there is one period of high volume and one period of low volume and a double regime where there are two distinct periods of a high volume of water in a year. Knowledge of a river regime is important to man in controlling floods, storing up water for irrigation and human consumption and also for planning H.E.P production.
7. A confluence: This refers to the meeting point of two rivers.
8. Tributaries: These are smaller rivers or streams that join together to form a larger river.
9. Distributaries: These are channels formed by the division of a river as it flows into the sea. They are usually found in the delta region of a river.
10. River energy: It refers to the velocity of a river. The efficiency of a river to erode and transport the eroded materials depends very much on its velocity.

FACTORS AFFECTING THE VELOCITY OF A RIVER

1. The volume of water released.
2. The slope of the river valley.
3. The shape of the river valley.
4. Amount and size of materials.

STAGES OF A RIVER

The entire length, valley or course of a river is divided into three main stages.

1. The upper course or mountain course (Youthful stage).
2. The middle course or valley course (Mature stage).
3. The lower course or plain course (Old stage).

UPPER COURSE OF A RIVER

CHARACTERISTICS OF UPPER COURSE OF A RIVER:

1. It marks the beginning or source of a River.
2. It is found around highland areas.
3. It has steep sides.
4. The river flows swiftly down the steep slope.
5. The dominant work of the river is vertical corrosion or erosion.

PROCESSES OF RIVER EROSION

The load or materials carried by a river are the main agents of erosion, but the erosive work of a river consists of four processes. These are:

1. Hydraulic action: In this process, fast-flowing water forces itself into cracks and joints within the valley under pressure and enlarges the cracks.
2. Corrosion: Corrosion is the wearing away of the sides and floor of the river with the aid of sand, pebbles, silts and boulders which are being transported. These materials eventually widen and deepen the river valley.
3. Attrition: This is the wearing down of the load as they collide with one another and with the floor and side of the valley. Large boulders are broken down into small pieces like pebbles.
4. Solution: This refers to the chemical action of water on materials it comes in contact with while flowing. Here, rock salt is dissolved and carried away in solution.

 FEATURES OF UPPER COURSE OF A RIVER

1. V-Shaped Valley
2. Gorge
3. River Capture
4. Rapid and Cataracts
5. Waterfall

  

In our next class, we will be talking more about the Action of Running Water.  We hope you enjoyed the class.

Should you have any further question, feel free to ask in the comment section below and trust us to respond as soon as possible.

Get more class notes, videos, homework help, exam practice on Android [DOWNLOAD]

Get more class notes, videos, homework help, exam practice on iPhone [DOWNLOAD]