From Earth Science On-Site
South Elmsall Quarry, West Yorkshire
It is anticipated that the ideas and materials presented here will be adapted by schools, and others, to be more appropriate for their own purposes and programmes of study.
In such circumstances please acknowledge the source as the Earth Science On-Site project.
It is best to read the signpost by the gate after the fieldwork, not before.
Enter the site through the wide gate in the north western corner and group the party close to the large stones in the centre of the grassy slope to get a general view of the site. (See Figure 1)
At the beginning of the visit, from the centre of the quarry, is the opportunity to focus pupils on the scientific nature of the activities. Select questions and themes most likely to engage your group.
It is possible for large groups to be divided into two and given similar exercises to do in different parts of the quarry whilst still being supervised. Using the field exercise sheets 1, 2 and 3 (the map) in pupil worksheets one group can work along the north face, and a second group can work along the northern half of the east face, allowing both to be under supervision. After about 30 minutes the groups can swap over and work on the other face. (Summaries of the main points for group leaders can be found in field notes)
At the end of these exercises establish by discussion of the pupils’ suggested origins for these structures on worksheet 2, that they are dealing with a stromatolite reef. Then give out worksheet 4 from the pupil worksheets.
After the discussion about the reefs, invite the pupils to search for the “other edge” of the reef and mark it on the map. They will need to follow the face around to the top of the SW corner of the site where the bedded rocks again can be seen. However, there are sites along the way which seem to have no reef structures, and pupils will need to be asked to “check their conclusions” further along the face.
NOTE: Photosynthetic blue-green algae now have a more accurate scientific name, that of cyanobacteria. That is, they are bacteria and not algae at all, although the term is widespread still in the literature. The reef structures are called stromatolites, which means they are sheet, or layered in shape. This means the term “algal” stromatolite reef is no longer current scientific usage. Due to a more accurate understanding of these organisms the term “cyanobacterial” reef might be used. Group leaders may want to stress this point with some groups to demonstrate the dynamic nature of science and the terms in use.
Finally re–group the party around the large stones in the centre of the quarry and summarise the key points. Guidance for this can be found in field notes.