THE DERIVATION AND DEFINITION OF THE SOUTHERN UPLAND FAULT - A REVIEWOF THE MIDLAND VALLEY - SOUTHERN UPLANDS TERRANE BOUNDARY

Although the Southern Upland Fault (SUF) is widely recognized as a maj or Caledonoid crustal structure in south Scotland, the derivation of t he term 'SUF' has never been definitively established. The historical background to the naming of the fault is discussed and a definition pr oposed for the Southern Upland Fault (sensu strictu). Traced towards b oth the SW and NE, the SUF (ss) is represented by multiple fault trace s, each the locus of a particular phase of movement. The evidence for the correlation of each fault is reviewed and recommendations for futu re fault nomenclature proposed. It is concluded that the Stinchar Vall ey Fault (Pyet Thrust) - SUF (ss) - Firth of Forth Fault line represen ts the original terrane boundary between the Southern Uplands and the Midland Valley of Scotland.