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RIGS FOR GEOGRAPHY EDUCATION

CAROLINE MARKHAM

The Geography National Curriculum at Key Stage 3 (11–14 years) indicates that pupils should, ‘In their study of countries and themes carry out field work investigations outside the classroom.’ It may help those responsible for RIGS to understand the form that these field investigations may take when using geological and geomorphological sites. Data on site record sheets of particular value to teachers includes details on the geology/geomorphology of the site, access information and hazard assessment.

Geological/geomorphological information has obvious benefits for educational visits to sites. The most straightforward field trip is the closed study, exemplified by a visit to Nacton Shore in October 2004 with Amberfield School Year 7 pupils (10–11 years). Here, horizontally bedded London Clay (Harwich Formation) clays, mudstone beds and ash bands exhibit a series of normal faults with downthrow on the east in exposures

Figure 1. An Amberfield School student demonstrates the displacement of a mudstone band by a fault in the London Clay at Nacton Shore. The fault may be seen above and to the left of her and is dipping at about 45°. Note also thin pale coloured beds of decomposed volcanic ash within the clay.

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created by active erosion by the River Orwell. This type of field study uses the landscape as an outdoor classroom and a basic understanding of structural geology using a worksheet and question/answer session can be achieved in about an hour. Students find the 3D geometry of the task easier to understand in the field and the impact of the spectacular cliff sections leaves a lasting impression.

Most longer field studies are enquiry-based. A question is posed and data collected with the aim of solving it. Asking appropriate questions is important and students have to work towards setting their own task by the time they undertake GCSE geography coursework. In June 2004 Year 7 pupils visited Dunwich for a whole day field enquiry, ‘How has coastal erosion affected Dunwich?’ This is a dynamic section of coast where the relationship between wave action, cliffs and beach is easy to see. The cliff comprises the pebbly gravels of the Westleton Beds on top of Norwich Crag Sands, unconsolidated material that is easily removed by marine erosion. A steeply sloping shingle beach lies in front of the cliffs, the rounded flint pebbles being in part supplied by frequent cliff falls of the Westleton Beds. The students measured the beach form and composition, made estimates of wave height and frequency, and sketched the cliff. The coast at Dunwich has been subjected to rapid retreat over the centuries and the students mapped evidence, in the village and surroundings, of the Medieval city and port which were lost to the sea. Dunwich is a site with exceptional educational value and outstanding natural beauty. Access is easy with a large car park next to the beach and so GeoSuffolk has made its information more accessible to non-geologists in the form of a special new leaflet, “Dunwich – the geology of Suffolk’s lost city”.

The excellent access at both Dunwich and Nacton Shore give them special value to teachers. It is of vital importance for site visits with 30 or more students. Problems with access may lead to compromise on quality of site visited. In May 2005 Year 8 students undertook a field enquiry into land use along the Orwell Estuary, ‘Is development along the Orwell Estuary sustainable?’ As well as visits to an industrial site in Ipswich, Felixstowe Dock and a marina, the natural landscape was studied. This involved a visit to the salt marsh and valley side landslide at Levington Marina. Neither are the best examples of their kind in the area and are not on GeoSuffolk’s potential RIGS list, nevertheless, access is easy and the landowner welcoming. On the salt marsh the students logged plant species, completed a litter count and pushed a 2 m cane into the mud. Their astonishment at the ease of this task will stay with them for some time. A large rotational slip on the valley side was inspected with tree girth measurements giving a minimum age of 80 years for the slope failure. Where it is not being actively undercut, the Harwich Formation forms attractive wooded slopes along the estuaries of the Orwell, Deben and Stour, often with spectacular evidence of past landslides and use of trees to date one of these at Fagbury Cliff, Felixstowe has been recorded by Markham (1997).

Teachers have to complete risk assessments for all off-site visits. The risk assessment for the Nacton Shore excursion described above was as follows:

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It is the responsibility of the teacher to assess the risks to the students of any particular activity, however a list of hazards for RIGS would be very valuable, especially for non-specialists and would be a welcome addition to site records. A hazard list for this site might look something like this:

• Water reaches the foot of the cliff at high tide. Check tides before visiting. • At low tide the foreshore is muddy. Do not venture onto this it is easy to

get stuck. • The cliffs are soft and liable to failure. Do not stand too close to the base

especially where there is evidence of undercutting. Landslides are particularly likely after heavy rain.

Reference Markham, R. (1997). A slip in time. White Admiral - Newsletter of the Suffolk

Naturalists’ Society, 37: 11.

Caroline Markham Amberfield School Nacton Suffolk IP10 0HL

Staff Names C Markham & R Markham

Student Group: U3H Date of Travel: 11.10.04

Location: Nacton Shore Time: 14·30–15·45 pm

Hazard Risk Likelihood/

severity

Action

Water Drowning Low Instruct students to stay away from

the shoreline. Low tide 16·42

Mud Getting Stuck Medium Instruct students to stay away from

the mud. Low tide 16·42, so plenty

of time for rescue.

Landslides Asphyxiation Medium Inspect site before trip. Wet

weather makes landslides more

likely. Stay away from areas likely

to fall, low tide gives plenty of

space.

Risk Assessment Check List