Southern Uplands

The Southern Uplands are the southernmost and least populous of mainland Scotland's three major geographic areas (the others being the Central Lowlands and the Highlands). The term is used both to describe the geographical region and to collectively denote the various ranges of hills and mountains within this region.

An overwhelmingly rural and mainly agricultural region, the Southern Uplands are partly forested and contain many areas of open moorland.

The Southern Uplands consist mainly of Silurian sedimentary deposits deposited in the Iapetus Ocean from 400–500 million years ago. These rocks were pushed up from the sea bed into an accretionary wedge during the Caledonian orogeny, roughly 400 million years ago (Ma), when the continents and terranes of Laurentia, Baltica and Avalonia collided. The Caledonian orogeny is named for Caledonia, a Latin name for Scotland. The majority of the rocks are weakly metamorphosed coarse greywacke.

The tectonic processes involved in the formation of the accretionary wedge, where sediment is scraped off the seafloor as a tectonic plate is subducted, has led to the formation of multiple, major, east-west faults that are now exploited by rivers and define valleys across the Southern Uplands. Levels of deformation associated with these faults is highly variable, but is pervasive in the finer-grained sediments. Secondary mineralisation has further altered these Lower Palaeozoic rocks which are hosts for some distinctive springs, some of which have been exploited for tourism, such as those around Moffat.

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