Geographical Investigation (Coasts) Flashcards
What does data collection involve?
Data collection involves using the appropriate data collection method, ensuring that the data collected is accurate and an appropriate data collection strategy to ensure that the data collected is reliable.
How is wave height calculated?
Height of wave crest - height of wave trough
How is wave length calculated?
1.56 x T^2 (T being the wave period)
How is wave frequency calculated?
Number of waves in 5 minutes / 5
How is wave steepness calculated?
Wave height / Wave length
How is wave period calculated?
Time taken for 10 wave crests to pass a ruler of ranging pole / 10
How do you measure beach gradient?
- identify a line of transect and using a measuring tape, mark out points of equal intervals of 2m (using systematic sampling)
- label these as points A, B, C, D so on (with point A at shoreline)
- stick ranging poles at points A and B, ensuring the poles same height and held vertically upright
- person at A should hold clinometer at eye lvl and align it with top of person’s head at B (ensure both persons are similar height)
- read the angle of elevation where the string crosses the scale on the curved edge of the protractor and record into a recording sheet
- repeat steps for 2-5 for the next few points
How do you find wind direction and sediment movement?
- using a wind vane, observe general direction of wind (general direction of longshore drift
- stick a ranging pole into the sand at the water’s edge (point A) (mark start of fieldwork)
- throw 11 oranges 1m away from the water’s edge
- using a stopwatcch observe travelling path of oranges for 10 min
- after 10 min, stick a 2nd ranging pole into sand at point B, which is the poition of the furthest orange
- identify direction of sediment movement by noting direction from of point A to B
How do you identify the type of sediment?
- Identify a line of transect and conduct random/stratified/systematic sampling along the line of transect.
- A set of sieves can be used to sort the sand particles. To do this, collect a 100-gram sample of sand.
- Pour the sand sediments through the set of sieves and weigh the sand retained on each sieve.
How do you identify samples of different particle sizes and angularity from a pebble beach?
- identify a line of transect and place a quadrat at equal intervals of 5m along (each) line of transect (if fieldwork is at a fixed point, just say ‘at point A’) (systematic sampling)
- using random sampling, select 10-15 samples from within quadrat (use random number generator)
- use vernier calipers to measure multiple axis of sediments at different positions (ensure callipers have been zeroed)
- calculate the average diameter of the sediments + record into recording sheet (ensure sediment sample dried)
What are the accuracy considerations when measuring wave height?
- Ensure that the ruler is held upright.
- Do not push the ruler into the sand.
- Take multiple measurements for height of crest and trough and average values.
What are the accuracy considerations when measuring wave frequency?
1.Use a digital stopwatch.
2. Count the number of waves over three minutes and obtain an average per minute.
3. Repeat measurement multiple times and average values.
What are the accuracy considerations when measuring wave period?
- Use a digital stopwatch.
- Repeat measurement multiple times and average values.
What are the accuracy considerations when measuring the gradient of the beach?
- Ranging poles must be the same height.
- Hold ranging poles vertically upright.
- Do not push ranging poles into the sand.
- Take multiple clinometer readings for each measurement and average values.
What are the accuracy considerations when measuring wind direction?
- Stand in an open area and make sure that the wind is not obstructed.
- Hold the wind vane above your head.
