Geological processes in the British Isles
Geological processes in the British Isles

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

Geological processes in the British Isles

5.4 Older Cover

Moving up succession, the next lithotectonic unit is the Older Cover. By referring to Figure 9 and Table 2 in conjunction with the Ten Mile Map, you should be able to see that throughout the British Isles, the Older Cover consists of Devonian (75–8) and Carboniferous (79–84) strata, with significant outcrops of Carboniferous volcanic rocks (53–5) occurring in the Midland Valley of Scotland. Minor Carboniferous volcanics also occur in the Derbyshire area around Matlock (SK(43)2560) and Buxton (SK(43)1074).

Examine the outcrop patterns on the Ten Mile Maps in relation to the areas covered by Older Cover in Figure 9, and attempt the following questions.

Question 11

Describe in one sentence each, the style of contact between the Older Cover and underlying Caledonian Orogenic Belt in the following areas:

  • (a) around the Moray Firth (NC(29)8510 and NH(28)6733);

  • (b) the Southern Uplands south-west of Berwick-upon-Tweed (NU(46)0053);

  • (c) the Lake District (e.g. NY(35)5810);

  • (d) northern and central Wales (e.g. SJ(33)2435).

Answer

In each of these areas, the Older Cover lies unconformably on top of rocks of the Caledonian Orogenic Belt.

Question 12

Similarly, what is the nature of the contacts between the Older Cover and underlying Caledonian Orogenic Belt on the northern and southern sides of the Midland Valley, on your Ten Mile Map (N) between:

  • (a) Helensburgh (NS(26)2982) and Stonehaven (NO(37)8786)?

  • (b) Girvan (NX(25)1898) and Dunbar (NT(36)6879)?

Answer

On both sides of the Midland Valley, the Older Cover is faulted against older rocks.

Question 13

Look carefully at the strata that make up the Older Cover between Manchester (SJ(33)89) and Sheffield (SK(43)38) on your Ten Mile Map (S). Describe the type and significance of the folding.

Answer

The Older Cover forms a gentle N–S trending anticline. This implies that the major direction of crustal shortening during this folding event was E–W.

SXR260_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus