File:GSG GLA FIG 00 11.jpg

English: Figure 0.11 Showing the evolution of the main tectonic elements, Highland Border Complex, (NBC); Midland Valley (MV) and the Southern Uplands (SU) through time. In the Ordovician they were distinctive terranes which were being produced somewhere along the southern margin of Laurentia, and then progessively came together. By Devonian times these terranes were probably all overlapping each other, almost, but not quite, in the positions we now see them. During this time when the terranes were accreting, many basins developed along their margins forming the fault basins of the Old Red Sandstone. By Carboniferous times, but already beginning in the Devonian, sheets of sandstone produced from the erosion of the Caledonian mountains of Scandinavia and Greenland spread over the terranes, thus demonstrating them to be in postion at that time.

From: Lawson, J.D. and Weedon, D.S. (editors). 1992. Geological excursions around Glasgow & Girvan. Glasgow : Geological Society of Glasgow.