The distribution of rock types in Scotland has ensured that Scotland is able to produce good quality rock aggregate almost anywhere in the country. In general all aggregate is derived from two main sources: deposits of sand and gravel, which are almost exclusively of glacial origin, and crushed rock aggregate from quarries mining solid rock.
Scotland is self-sufficient in aggregate production (and, in fact, exports aggregates). The annual amount of crushed rock aggregate is more than twice that of sand and gravel, with a total annual production of about 33 x 106 tonnes. Figure 18.1 shows the annual production of aggregate from 1972 to 1998 (BGS 1972 et seq.) and indicates that production continued to increase (or at worst plateaued out) during the recession from 1990 to 1995, in spite of UK total production showing an overall reduction of over 20% during this period. The graph shows that the annual production of sand and gravel has fallen slightly from 12 x 106 to about 10 x 106 tonnes per annum, and that hard rock production is now more than 23 x 106 tonnes per annum. It should be emphasized that a crushed rock granite quarry at Glensanda on Loch Linnhe which started in 1987 accounts for more than 5 x 106 tonnes of the crushed rock annual production. This quarry, the first custom- designed superquarry in Scotland, sends material to southeastern England, and also to northern Europe and the United States (see below).
Figures & Tables
This 4th edition of The Geology of Scotland is edited by Dr Nigel Trewin of the Department of Geology and Petroleum Geology at the University of Aberdeen. The volume is greatly expanded from the previous edition with 34 authors contributing to 20 chapters.
A new format has been adopted to provide a different perspective on the geology of Scotland. A brief Introduction is followed by a chapter outlining some of the important historical aspects that in the 19th century placed Scottish geologists at the forefront of a new science.
Scotland is constructed from a number of terranes that finally combined in roughly their present positions prior to about 410 million years ago. Thus the geology of each terrane is described up to the time of amalgamation, providing chapters on the Southern Uplands, Midland Valley, Northern Highland, Grampian and Hebridean terranes. At the end of this section, a brief synthesis summarizes the events that resulted in the amalgamation of the various terranes into the present configuration.
Traditional practice is followed in the description of the Old Red Sandstone, Carboniferous, Permo-Trias, Jurassic, Cretaceous, Tertiary and Quaternary strata. A separate chapter covers Tertiary igneous rocks. An attempt is made to tell the story of the geological evolution of Scotland, rather than catalogue all areas and formations. Priority is given to the onshore geology, encouraging the reader to go into the field and visit some of the world-class geology on show in Scotland. The chapters are broadly-based, attempting to integrate the sedimentary and igneous histories, and summarize changes in palaeogeography and palaeoenvironments.
Economic aspects are covered with chapters on Metalliferous Minerals, Bulk Resources, Coal and Hydrocarbons. A new departure is a chapter on aspects of Environmental Geology and sustainability.
Additionally, this publication contains a colour section of 32 plates, illustrating aspects of Scottish Geology, as well as a coloured geological map of Scotland.