Pre-Late Devensian high-arctic marine deposits in SW Scotland

Abstract

SynopsisWe present new interpretations of Digital Elevation Model (DEM) data and marine fossils collected from three sites on the Rhins of Galloway which, contrary to recent proposals, suggest that the landforms and deposits of the region do not represent evidence for a readvance during the Lateglacial Period. Rather we suggest that the higharctic fauna found in the region are representative of an earlier, colder part of a Middle Devensian ice-free interval. The predominantly streamlined topography, and distinct lack of identifiable discrete moraine limits argues for only minor, local glacial advances, in combination with widespread rapid retreat across the peninsula at the end of the Lateglacial.

Ice sheet advance, dynamics, and decay configurations: evidence from west central Scotland

“…Ridge, at the head of Loch Indaal, Islay Merritt, 1997), Stranraer (Charlesworth, 1926;Peacock and Everest, 2009), and at Armoy and east Antrim on the northeastern Irish coast (McCabe, 2008) We suggest that moraine building at Blantyreferme and Kilmarnock (Fig. 5), occurred during the same overall phase of events.…”

Late Pleistocene sediments, landforms and events in Scotland: a review of the terrestrial stratigraphic record

“…2014), other localities around the coasts of the Firth of Clyde and Kintyre (Finlayson et al . 2010, 2014), the Rhins of Galloway (Peacock & Everest 2016), Clava, near Inverness (Merritt 1992), sites along the southern coast of the Moray Firth (Merritt et al . 2003) and the North Sea coast of the Grampian Highlands (Auton et al .…”

“…The enigmatic 'high-level' shelly clay deposits located around the Scottish coast ) are now all interpreted as glacially transported rafts of marine sediment rather than remnant in situ deposits formed during periods of high RSL before the Last glaciation (Sutherland 1981). Localities include Afton Lodge, in Ayrshire (Merritt et al 2014), other localities around the coasts of the Firth of Clyde and Kintyre (Finlayson et al 2010(Finlayson et al , 2014, the Rhins of Galloway (Peacock & Everest 2016), Clava, near Inverness (Merritt 1992), sites along the southern coast of the Moray Firth (Merritt et al 2003) and the North Sea coast of the Grampian Highlands (Auton et al 2000). Much of the controversy has centred on the local field evidence of ice flow, which Sutherland (1981) concluded to be generally offshore rather than onshore as required in the rafting model.…”

“…Merritt et al (2014) conclude that the rafts of Afton Lodge Clay were detached and entrained into the deforming layer beneath the ice at this stage as it advanced from the Firth of Clyde basin SE towards Nith Bridge, near New Cumnock (Sutherland 1993g) (Fig. 30), and S to Stranraer, the most southerly-known occurrence of shelly diamicton in Scotland (Phillips et al 2009;Peacock & Everest 2016). The advance of ice into the Clyde basin resulted in ponding (Price 1975) and the ribbed moraine may have been initiated locally as ice-marginal sediment ridges generated by folding and thrusting (McMillan & Browne 1983;Finlayson 2012).…”

“…30), and S to Stranraer, the most southerly known occurrence of shelly diamicton in Scotland (Phillips et al . 2009; Peacock & Everest 2016). The advance of ice into the Clyde basin resulted in ponding (Price 1975) and the ribbed moraine may have been initiated locally as ice-marginal sediment ridges generated by folding and thrusting (McMillan & Browne 1983; Finlayson 2012).…”