Year 7 Geography- Rivers (G and Y groups) Lesson 5 – Explain how a meander and an oxbow lake are formed Success criteria: I can define meander and oxbow lake I can explain how a meander is formed I can explain how a meander becomes an oxbow lake I can draw and label a series of diagrams showing meander formation Do now: 1. Rivers are used in agriculture for I… 2. When water it is evaporated from plants it is called… 3. Deposition occurs when a river loses… 4. What is formed when a waterfall retreats (moves backwards) upstream? 5. What is it called when HICs help LICs to develop? 6. Challenge: abrasion is when… Meanders: Start by watching this video: https://www.bbc.co.uk/bitesize/clips/zvm3cdm A meander is a bend in a river It starts with a slight bend. The The fast water erodes the Continued erosion and water moves faster on the outside of the bend. The deposition makes the bend outside of the bend and slower slower water deposits material bigger. on the inside of the bend. on the inside of the bend. Complete the sentences below: A meander is __________________________________________________________________________________ A meander starts with a… The fast water… the… Continued e… on the... of the bend. of the bend, and d… on the… Water moves fastest… of the bend makes... The slow water… material on Water moves slowest… the… of the bend. Label the diagram with the key words – meander, erosion and deposition (To label, draw a text box where you want the label to go, and type in it). Challenge: suggest two types of erosion that occur on the outside of the bend ________________________________________________________________ ________________________________________________________________ Oxbow lakes: Start by watching this video: https://www.bbc.co.uk/bitesize/clips/zrhc87h An oxbow lake is a U shaped lake near a river Over time, erosion makes the Eventually the neck of the As less water is flowing through meander bend larger and larger. meander breaks through and the the meander, the energy is The neck of the meander water takes the most direct reduced. Material is deposited, narrows. route, avoiding the meander. blocking off the meander and creating an oxbow lake. 1. Complete the sentence starters on the next page. 2. Draw on arrows showing direction of flow (Insert, shapes, pick the arrow symbol) 3. Label the diagram with the key words – deposition, erosion, neck, oxbow lake, meander Using the structure below, explain what will happen to the landform in the picture over time. Try to use the following words in your answer: erosion, hydraulic action, deposition, neck, fastest route, energy The image shows a… which is formed due to…. Over time this will develop into… (Explain how this happens). Firstly…. Secondly…. Finally… _____________________________________________________________________________________________________________________________ _______________ ____________________________________________________________________________________________________________________________________________ _____________________________________________________________________________________________________________________________ _______________ ____________________________________________________________________________________________________________________________________________ ____________________________________________________________________________________________________________________________________________ ____________________________________________________________________________________________________________________________________________ ____________________________________________________________________________________________________________________________________________ ____________________________________________________________________________________________________________________________________________ Challenge: without using your notes, try to draw (on paper) the three stages of the formation of a meander. Label it with the key words .