Fieldwork Flashcards
What was the aim of the physical fieldwork?
To investigate how river depth, speed and load change across the bend of a river
What was the hypothesis?
The river is deeper on the outside, the river is faster on the outside, the river load is smaller on the outside
Describe the location
Borrowdale at ‘Grange’- a tributary of the river Derwent
Why was the location suitable?
It was safe and accessible, it was near to Keswick, appropriate for investigation, meander
What were the risks?
There were slippery rocks, there was fast flowing water, debris in river, uneven river bed
How were the risks reduced?
Facing upstream, bending knees, aware of surrowndings, focus on task, work in teams, suitable shoes and clothes, warned, moving slowly, supervision
How was the width of the river measured?
One prson stands on the river bank, second person walks across the river with the end of the tape measure, tape measure is kept tight and above the river, width is read out and written down by a group member on the river bank
What were the problems with measuring the width of the river?
The tape measure got caught in the channel making the river seems wider than it actually was
How was the depth of the river measured?
While the tape is being held across the river by two group members, a third group member uses a metre ruler to measure the dpth across the river at every 50cm, the depth is read out and recorded by a group member on the river bank
What were the problems with measuring the depth?
Pushing the metre ruler down too hard may make the channel seem deeper than it actually was
How was the speed of the river of the river measured?
One person holds the flow metre in the river channel with the propeller facing upstream, it is held in the water for one minute and the digital reading is read out to the person on the river bank who records it, this is completeted at three locations across the channel- at each edge and in the middle
What were the problems with measuring the speed?
There were people upstream from each group doing the same measurements which could affect the speed of the water, it was difficult to hold the flow metre still, the distance across the river channel was not measured, it was just guessed
How was the bed load measured?
At every 100cm across the river channel a rock from the river bed was picked up and passed tot he person on the river bank, this person then measured the longest length of the rock and qrote the measurement down to the nearest 0.5cm
What were the problems with measuring the bed load?
Most people always went to pick up the biggest rock which might skew the results, only one rock was picked up from each location, should measure all sides, use callipers, take more samples at each point
What did the data for depth show?
The depth data was presented as a cross sectional diagram, the cross section shows that the river was deepest on the outside bend of the river, the inside bend was 15cm deep whereas the outside bend was 73cm deep at its deepest, this is because the river travels fastest on the outside bend so it has more erosive power (it erodes more because it is faster and has more power), this makes the channel deeper, there was a slight anomally because the deepest point was 7 metres across the channel, the river then got shallower (65cm) and then deeper again (68cm), it is not a smooth, perfect example
