CR/15/128; Final
Last modified: 2016/01/18 16:31
25,000 years ago. During deglaciation, the dynamic interaction of Highland and Southern Upland glaciers retreating towards the west resulted in the formation of a complex assemblage of ice marginal sediments and landforms. As the ice retreated, the drainage system of the River Clyde and its tributaries was re-established over the glaciated terrain. Glacial sediments had infilled most of the pre-existing valleys in the central area of the Clyde catchment (from Lanark to Hamilton) and powerful streams charged with glacial meltwater and outflows from glacial lakes, carved a network of new valleys deep into the glacial sediment and bedrock. The deep gorges resulting from this erosion, and the picturesque waterfalls within them, form some of the most striking geological features of the region.
Figure 2 – Simplified geological map of the Midland Valley of Scotland with timeline. Major geological faults are shown by a thick black line with a tick on the downthrown side (Source: BGS DiGMapGB data).
3 Geological history of the Clyde and Avon Valleys Sites of geological interest are distributed throughout the CAVLP area (Figure 1). The rocks, superficial deposits, and the area’s dramatic landforms are testimony to the power of rivers to shape the landscape over millions of years. In particular, the CAVLP area provides perhaps the best example in Scotland of the disruptive influence of glaciation on pre-glacial drainage systems due to its unique geographical setting. Moreover, the region and its communities continue to be shaped by the rivers today. The dynamic power of the rivers forms a strong narrative thread linking the landscapes of the past with the landscapes of the present. The following discussion of the geological history of the area, demonstrated through its geological sites, highlights the central role of rivers throughout geological history of the CAVLP area. 7