Coastal Fieldwork: Data Collection Techniques

Recording the shape and material of a beach

Coastal fieldwork turns observations of a landscape into evidence that can help answer an enquiry question. Two beaches might look different, but measurements allow you to describe precisely how their slopes or sediment differ.

Beach morphology means the shape of a beach, including its slopes and changes in height. Sediment characteristics describe the material forming the beach, including particle size and roundness. Measuring these produces quantitative data: numbers that can be compared between locations. Photographs and annotated field sketches provide qualitative data, recording the appearance and arrangement of coastal landforms.

These methods complement one another. A measured profile records beach slopes, while a photograph or sketch shows the landscape in which those measurements were taken.

Measuring a beach profile

A beach profile is a measured cross-section of the beach. Collecting distance and angle measurements along a transect allows you to record changes in slope rather than treating the whole beach as one uniform surface.

You need a tape measure, two ranging poles, a clinometer and a recording sheet. Ranging poles provide clearly visible reference points; a clinometer measures slope angle in degrees.

1. Choose a transect running from a safe position near the sea towards the back of the beach.
2. Place the first ranging pole at the starting point and the second at the next break of slope, where the beach becomes steeper, gentler or changes slope direction.
3. Measure and record the distance between the poles in metres.
4. Use the clinometer to sight between matching height markers on the two upright poles. Record the angle in degrees. Matching markers ensure that the measurement represents the beach slope rather than a difference in sighting height.
5. Move the poles to measure the next section. Continue from one break of slope to the next until you reach the top of the beach.

Keep the measurements in sequence, recording whether each section rises or falls in the direction of the survey. This preserves the shape of the beach, including any sections that slope differently from those beside them.

Profiles taken at different locations can reveal differences in beach morphology. Keep the method consistent between sites and record where each transect begins and ends. A profile is a record of conditions at the time of the survey, not proof that the beach always has that shape.

Measuring sediment characteristics

Sediment analysis records the material making up the beach. To investigate variation across its width, collect samples at planned positions along the transect. To compare different parts of the coastline, repeat the same procedure at several sites.

You cannot measure every pebble, so the way you select a sample matters. Systematic sampling uses regular intervals; random sampling uses chance to select positions. A quadrat can define the area from which sediment is sampled. Avoid selecting only the largest or most noticeable stones, because they may not represent the beach material.

For pebbles, use callipers to measure size and record the results in millimetres. Use the same dimension for every pebble—for example, its longest dimension—so the measurements are comparable. Record each measurement rather than relying on a general description such as ‘large pebbles’. A mean can summarise the sample, but the individual measurements also show how much sizes vary.

Pebble roundness is a different characteristic from size. Compare each pebble with a roundness chart and classify it as very angular, angular, sub-angular, sub-rounded, rounded or very rounded. A large pebble can be rounded, while a small one can be angular: these categories do not measure particle size.

Roundness is judged by eye, so different observers may classify the same pebble differently. Using the same chart and agreeing how to apply its categories makes comparisons more consistent. Together, size measurements and roundness observations provide evidence for investigating how beach sediment varies between locations.

Recording coastal landforms with sketches and photographs

An annotated field sketch records the important features of a coastal landscape without attempting to copy every detail. It is useful for showing how landforms are arranged relative to one another and for selecting features relevant to the enquiry.

Choose a safe viewpoint from which the relevant features can be seen. Draw the main outlines first, then add the landforms you can identify, such as the beach and cliffs. Record the location, date and viewing direction so that the sketch can be understood later.

Add annotations that describe evidence rather than merely naming features. For example, in an observation of a spit, the label ‘spit’ could be developed into: ‘An extended stretch of beach material projects into the sea and remains joined to the mainland at one end.’ This records the shape and relationship that identify the landform.

A photograph captures more visible detail and can also record how fieldwork equipment was used. Record its location and viewing direction, then annotate the relevant features. Neither a photograph nor a sketch directly measures slope angle or pebble size, so use them alongside quantitative measurements.

Field sketches are quick and help you focus on key features, but the observer decides what to include. Photographs retain detail, but their viewpoint can hide features or make distances and slopes difficult to judge. An interpretation should therefore distinguish what is visible from what is inferred about coastal processes.

Collecting comparable evidence safely

Use the same measurement procedures at each site and record locations using GPS or a map grid reference. Repeated measurements and several samples help you judge whether a result represents a wider pattern rather than one unusual section or pebble.

Safety can limit where evidence is collected. Check tide times and weather conditions, use suitable footwear on slippery surfaces, and avoid unstable cliffs or rockfall areas. If an intended site is unsafe, use the nearest suitable safe location and record the change. This makes the limitation clear without placing the investigation ahead of safety.