Information about rivers.
Source of a river - where a river begins. Usually high up eg on a mountain because rivers always flow downwards. Even if a river looks flat it is still moving downward which means gravity helps to move the water downwards. An example is when you drop a small stone or stick into the water and it moves down the river.
Mouth of a river - where a river ends and flows into another river or the sea.
Floodplain - the area of flat land around a river that floods when the river overflows.
Tributary - a smaller river that flows into a larger river.
Confluence - a point where two rivers meet.
Upper course - a steep, upland area of a river near the source. The load is larger because less erosion has happened.
Lower course - a flatter lower area of a river nearer the mouth. The load is made up of finer sediment that has eroded over time.
Information about erosion.
Hydraulic action - the power of the river water smashing against the river banks. Water gets trapped in cracks causing freeze thaw weathering.
Freeze thaw weathering - when the water trapped in cracks freezes and expands in cold conditions. When it warms up the water thaws and returns to its original size. This happens repeatedly putting pressure on the rock until it begins to crack and break.
Attrition - when rocks bang into each other braking apart into smaller pieces.
Abrasion - when pebbles and stones grind against the river bed eroding it.
Solution - when water can dissolve certain rocks eg. limestone.
Information about transportation.
Traction - when large heavy pebbles and stones are rolled along the river bed.
Saltation - when pebbles are bounced along the river bed.
Suspension - when lighter sediment is suspended in the water and carried along with the water.
Solution - the river carrying dissolved rock in the water.
Deposition - when the river loses energy and drops rock and sediment it has been carrying. Common in shallower water near the mouth of the river or when the volume of water decreases.
How to do this EarthCache :
To complete this EarthCache start at the posted coordinates and follow the short walk along the river visiting the waypoints. The walk takes between 30-40 minutes and can easily be completed in the 1 hour free parking available in the town centre. This EarthCache is not wheelchair or pushchair accessable. To log answer the following questions and send me the answers via Geocaching messaging centre or email. Do not put any answers in your log and no photos that could be used to answer questions please. You do not need to wait for a reply to your answers before logging. Warning - in autumn and winter or after heavy rain the footpaths can be slippy and muddy.
Questions :
1) Where is the floodplain of cod beck?
2)What evidence of can you see erosion in cod beck? What type of erosion do you think it is?
3) See if you can observe any evidence of transportation in Cod Beck and can you identify the type?
4) Can you see any evidence of deposition in cod beck and where?
5) From your observations do you think that this area of Cod Beck is in its upper or lower course? What evidence can you see?
6) What do you think is the cause of the river splitting into 2 leaving an island in the middle and why is this not a confluence? Do you think it will join back together?
I hope you enjoy this River walk and EarthCache.