The Climatostratigraphic Subdivision of the Devensian Lateglacial: Evidence from a Pollen Site Near Oban, Western Scotland

Abstract

Two percentage-based and one concentration- based pollen diagrams are presented from a Devensian Lateglacial site at Pulpit Hill, near Oban, Argyll. The site provides evidence to suggest that the early part of the Late- glacial Interstadial is interrupted by a brief phase of deteri- orating climate, and that the relative warmth of the later Interstadial gives way to a further and more prolonged de- terioration, substantially earlier than the Loch Lomond Sta- dial. A trend to increasing aridity within the Loch Lomond Stadial is detected. The reality of the Older Dryas stage in northern Britain is discussed, and is thought not to be demonstrated. Most sites which have been thought to relate to this stage appear not to satisfy particular criteria for the recognition of phases of deteriorating climate. Nevertheless, certain sites are thought to show early- to mid-Interstadial climatic deterio- rations, sufficient to require a revision of the current strati- graphic terminology, although 14C dating is urgently needed to test the presumed synchroneity of this event. This period at Pulpit Hill is compared with the later Loch Lomond Stadial, and from palynological, sedimentological and geochemical data, is thought to represent a comparably harsh climate.