GI - Coasts Flashcards
Safety precautions students have to take AT the fieldwork site
- —> be aware of surroundings
- —> so that students will not be caught in any sudden environmental change that will endanger their lives
- —> always work in groups
- —> so that in the event of an emergency, it is easier to call for aid
—-> take note of nearby shelters from lighting risks or heavy rainfall
what info do students need before starting field investigation?
- —> find out tide times
- —> dangerous to carry out a field investigation when there is high tide
- —> find out weather conditions
- —> avoid stormy weather as it could compromise their safety
- —> find out wind conditions like strong winds
- —> strong winds cause waves to swell
Describe a method to determine sediment movement
- —> use wind vane to find direction of wind
- —> record direction of wind
- —> near the water’s edge, stick the 1st ranging pole into the sand
- —> Throw the orange a metre away from the water’s edge
- —> observe the patterns of the traveling path of the oranges for 10 min
- —> stick 2nd ranging pole where the orange finally lands after being moved by a series of swash and backwash
- —> use measuring tape to measure distance between 2 poles
- —> identify direction of sentiment movement by noting the position of the 2nd pole in relation to the 1st pole
Method to find beach gradient
- stick ranging pole at the water’s edge
- use measuring tape to measure distance of 2m from 1st ranging pole to the next pole.
- At the Om mark, position clinometer at top of first ranging pole
- Aim clinometer at top part of 2nd ranging pole at 2m mark. Take note of angle of elevation
- Record angle in recording sheet. Repeat 2 to 5 times at every 2m interval
- Plot values
x-axis: points of measurements
y-axis: beach gradient
method to find beach material (pebble beach)
- Stick ranging pole at the water’s edge
- Measure distance of 2m from the 1st ranging pole to the next pole
3.place a quadrat - 10-15 samples of pebbles picked from within the quadrat using (sampling method)
5.measure using vernier caliper - angularity of pebbles determined by referring to Power’s scale of roundness
method to find beach material (sandy beach)
- stick ranging pole at water’s edge
- measure distance of 2m from 1st ranging pole to next pole
- collect and label 100g sample using (sampling method)
- pour sand sediments through sieves
- use particle size card to determine average size of sendiments
- weigh sand retained on each sieve
- calculate percentage of sand sediments retained from original sample of 100g
systematic sampling
samples collected with regular intervals in between
random sampling
collected without any fixed method (rolling dice)
reduces human bias
stratified sampling
divided according to specific characteristics
bias
wave height
vertical distance between the crest and trough of wave
wave length
horizontal distance from crest to crest or trough to trough
wave frequency
number of waves in 10 min / 10
wave steepness
wave height/wavelength
wave period
time taken for 10 wave crests to pass a ranging pole/10