GEOLOGICAL MAPPING COURSE PROPOSAL
FOREST OF DEAN, GLOUCESTERSHIRE
Dr N. CHIDLAW
This proposal is intended for OU students who wish to supplement their existing experience of the techniques of geological mapping. It was first run in 2000, following requests by students who wished to improve their skills and gain more confidence in the field, and supported by Earth Science staff at Milton Keynes. It has been run successfully several times since.
The tutor is a geologist with 30 years of post-graduate experience in teaching, research, publishing and industrial consulting. As a research student, he studied the sedimentology of Early Jurassic strata in the Cotswolds, carried out at the former St Paul and St Mary College Cheltenham (now the University of Gloucestershire), and the University of Bristol. During this time he taught undergraduates thin section petrography and field mapping skills (Arran, Lake District, Lizard). In the late 1980’s he worked as a part-time OU tutor on the Science Foundation course in Bristol, and has taught adult education courses for Bristol University for over 20 years. He now runs adult education courses for Cardiff University, together with courses and trips on a privately-arranged basis.
The proposed mapping course would run for 3 days, a Friday – Sunday, and would involve the first 2 days in the field, with the 3rd day indoors drawing up a fair copy of the map, together with final discussion of the results. The central purpose of the course is for students to gain extensive practice and thus confidence in the use of the compass/clinometer (the essential mapping tool), in referring to field maps and progressively marking on their collected data on these maps, and finally in producing a fair copy of their map. The aim is to establish the surface extent and structure of the geological units cropping out in the study area by concentrating on the above process. Working out the rock types and their succession would not be required – this would involve a longer course and a wider range of skills; instead a geological column with lithological details of the rock units in the study area would be provided and referred to.
The mapping area is in the Forest of Dean and consists entirely of sedimentary rocks. It is small, about 1.0 – 0.75 km, but has a great variety of well-exposed, distinct mappable rock units which allows the production of a very pleasing map. There are plentiful opportunities to take dip and strike readings on clearly-exposed bedding surfaces. The area is one where there has been extensive exploitation of industrial ‘minerals’ (including iron ore, coal, limestones, dolomites and sandstones), beginning in probably Roman – Medieval times, reaching a peak in the 19th century, and continuing to the present. Virtually all the workings are now abandoned. Rock exposures occur in quarries, small opencast mines and railway cuttings, and there are opportunities to trace the approximate positions of certain rock units by recognising and mapping abandoned mine entrances.
The third day of the course, on which collected field data is transferred under guidance onto a fair copy of the base map, would be held in a teaching room of a local education centre (e.g. a school), and the results discussed using slides of exposures in the study area, and overhead transparencies of the tutor’s own mapping. No marking of the work would be undertaken: there would be no ‘pass’ or ‘fail’ or grading; the course is essentially one in which skills are practised and results are discussed, each student judging for his/herself what they have learned and where future improvement could be made.
The course thus gives experience of practising the essential skills of geological mapping that any un-industrialised location provides (e.g. parts of the Scottish Highlands), whilst also enabling students to recognise and utilise evidence from past mining and quarrying; the latter is very important to professional geologists today working in areas with a long industrial history such as Britain and Europe.
Please email me directly for further information: