Early Holocene loessic colluviation in northwest England: new evidence for the 8.2 ka event in the terrestrial record?

摘要: Vincent, P. J., Lord, T. C., Telfer, M. W. & Wilson, 2010: Early Holocene loessic colluviation in northwest England: new evidence for the 8.2 ka event terrestrial record? Boreas, 10.1111/j.1502-3885.2010.00172.x. ISSN 0300-9483. Twelve samples of silts from widely spaced locations on karst uplands England have yielded Optically Stimulated Luminescence (OSL) dates that fall within or overlap with (within uncertainties) early to mid-Holocene period (11.7–6.0 ka), and support three already-published ages similar sediment this region. Nine 15 are coincident hypothesized climatic deterioration at 8.5–8.0 ka North Atlantic region eight event. These demonstrate not primary air-fall loesses deglacial/Lateglacial age (c. 18.0–11.7 ka) but been reworked now consist loess-derived colluvial deposits; we consider be reliable as there is no compelling indicate partially bleached. There substantive archaeological palynological Late Mesolithic hunter-gatherers having had a major impact landscape, it considered highly unlikely these people triggered colluviation. We estimate during was reduction mean annual air temperature upland ∼2.6–4.6 °C, proxy other sites indicates shift wetter conditions. It inferred greater snow accumulation winter, snowpack survived longer periods, an increase magnitude frequency frost-related processes meltwater flooding. Together, changes climate their associated (sub)surface were responsible reworking loess. The OSL climatically induced landscape dynamism Great Britain latter half ninth millennium.