Why is the weather so bad at the moment?

By the end of the lesson you will;

1)Be able to describe how different factors will affect the flood hydrograph2)Be able to explain the different stages of a river 3)Be able to explain how waterfalls are formed4)Demonstrate your understanding of new key words

Rivers

Homework review

Task 1; 1.We are going to go through the list of key words2.Make sure you have the perfect definition written down 3.Give yourself a mark out of 18.

Key words

EvaporationPrecipitationEvapotranspirationInterceptionTranspirationCondensationSurface runoff / overland flowHydrological cycleWater TableInfiltrationThrough flowGroundwater flowPercolationLeaf dripSurface StoragePermeableImpermeableSaturated

Task 2; 1.You need to choose 6 words2.Put them in a grid 3.When you get a line of 3 shout BINGO!

Impacts on the River;

Task; Draw a sketch for the following hydrographs;

An area where there has been large scale deforestation An area where there is permeable rock such as ChalkA built up area ( village) An area that is built up and has lots of trees An area where there is semi- porous rock such as clay Christchurch

By the end of the lesson you will;

1)Be able to describe how different factors will affect the flood hydrograph2)Be able to explain the different stages of a river 3)Be able to explain how waterfalls are formed4)Demonstrate your understanding of new key words

Rivers

River Characteristics

TaskWhat are the main changes that happen as you go down from the Source to the Mouth of the River?

Task 2; What will happen to the size? What will happen to the size of the load? What will happen to the amount of load? What will happen to the volume of water? What will happen to the speed of water?

Key Processes; River Erosion

Task1.Watch the following video clip 2.Match up the key words and their definitions in the table below

Key Word Definition

Abrasion the force of the water dislodges particles from the river’s bed and banks usually after a waterfall

Attrition when acids in the water dissolve minerals in the rocks- removal of chemical ions especially calcium

Hydraulic action

wearing away of rock usually causing small and rounded pebbles

Solution wearing away of the bed and bank by the load of a river: smoothing them- think of sand paper

Key Processes; Transportation

Task

You are going to sit back to back You need to choose one person to

describe what is in the diagram Explain what key processes are

occurring in the diagram

Key processes

SaltationSolution

Suspension Traction

Extension;

1.Which of the different processes occurs the most in rivers? 2.Which occurs the least in rivers? 3.Explain you answers

Key Processes; Deposition

Task1.The closer you get to the river mouth, the more deposition occurs2.Why does a river deposit its load? 3.Work as a pair to explain why using all of the key words

The river in the lower course will have a wider channel, and a decreased channel speed. This means that it will have less energy to carry the

sediment. When it reaches the sea, the sediment will be deposited on the bottom of the river

channel.

By the end of the lesson you will;

1)Be able to describe how different factors will affect the flood hydrograph2)Be able to explain the different stages of a river 3)Be able to explain how waterfalls are formed4)Demonstrate your understanding of new key words

Rivers

The Upper Course of a River;

Task1.Watch the following clip 2.Describe what the upper course of the river is like 3.Try to name some of the features which you can see.

How are waterfalls created?

Task1.Study the following diagram 2.How do you think this leads to the formation of a waterfall? 3.Work in a pair

Water flows down a river

Hard Rock

Soft Rock

Key Words; Hydraulic Action, Abrasion, Solution, Erosion, Cap Rock, Gulley, Plunge Pool

Key Words; Hydraulic Action, Abrasion, Solution, Erosion, Cap Rock, Gulley, Plunge Pool

How are waterfalls formed;

Task1.Cut out the following statements2.Put them in the correct order to explain how waterfalls have been formed

Water flows over hard rock that has soft rock underneath

Over time this crack will get bigger and bigger until it reaches te soft rock.

This crack will be made bigger by erosion such as Hydraulic action and Abrasion

As it moves back, it will leave behind a river with cliffs surrounding

Eventually the overhang will not have enough support, and so will fall down into the plunge pool

There will be the washing out of the soft rock by erosion such as hydraulic action and abrasion.

A small crack develops in the hard rock

The waterfall will eventually move back towards the source

Over time, this rock will start to hang over the plunge pool. This is called an overhang

When it reaches the soft rock, the erosion will be faster

This is because hydraulic action, abrasion and solution are wearing away the soft rock underneath

The hard resistant rock is called the cap rock

The process will start all over again

This is called a gorge The soft rock will start to undercut the hard rock and form a pool called a plunge pool

The overhang will get bigger and bigger and have less support underneath it

Water flows over hard rock that has soft rock underneath

A small crack develops in the hard rock

This crack will be made bigger by erosion such as Hydraulic action and Abrasion

Over time this crack will get bigger and bigger until it reaches te soft rock.

When it reaches the soft rock, the erosion will be faster

There will be the washing out of the soft rock by erosion such as hydraulic action and abrasion.

The soft rock will start to undercut the hard rock and form a pool called a plunge pool

The hard resistant rock is called the cap rock

Over time, this rock will start to hang over the plunge pool. This is called an overhang

The overhang will get bigger and bigger and have less support underneath it

This is because hydraulic action, abrasion and solution are wearing away the soft rock underneath

Eventually the overhang will not have enough support, and so will fall down into the plunge pool

The process will start all over again

The waterfall will eventually move back towards the source

As it moves back, it will leave behind a river with cliffs surrounding

This is called a gorge

Waterfall Creation

Task

1.Stick the sheet into your books 2.Add in the key words to the boxes below Key words

Corrasion / Abrasion Hard resistant Soft less resistant Gorge Plunge pool Extension; Can you add in any other labels to help you in a waterfall formation?

By the end of the lesson you will;

1)Be able to describe how different factors will affect the flood hydrograph2)Be able to explain the different stages of a river 3)Be able to explain how waterfalls are formed4)Demonstrate your understanding of new key words

Rivers

Key word Bingo

Task

Pick 9 words from the list of key wordsTry to get a run of 3 words When you do…shout BINGO!

Key words

EvaporationPrecipitationEvapotranspirationInterceptionTranspirationCondensationSurface runoff / overland flowHydrological cycleWater TableInfiltrationThrough flowGroundwater flowPercolationLeaf dripSurface StoragePermeableImpermeableSaturatedCap Rock Abrasion Solution Attrition Hydraulic action Gorge Upper course Middle course Lower course Plunge pool