The Buchan Palaeosurface

BuchanBuchan displays some of the clearest evidence for long-term regional geomorphological development in Scotland. The metamorphic and igneous basement was first exposed in the Devonian and repeatedly buried and re-exposed later in the PalaeozoicPalaeozoic and MesozoicMesozoic. Greensand, chert and flint remnants attest to a former CretaceousCretaceous sedimentary cover. The highest terrain in eastern BuchanBuchan supports remnants of deep kaolinitic weathering profiles and flint and quartziteQuartzite gravels. Oxygen isotopes indicate that kaolinizationWeathering processkaolinization occurred in two phases at mean annual temperatures of 23 and 15 °C, indicating a PalaeogenePalaeogene age for the flint gravels. Sandy deep weathering mainly formed from the Late MioceneMiocene onwards. By the onset of PleistocenePleistocene glaciation, differences in mineralogy and fracturing had been etched out by long-term weathering to produce basement terrain that was subtly but pervasively adjusted to rock type and structure. Weathering patterns exerted significant control over glacial and periglacial processes, but the impact of PleistocenePleistocene glacial erosion was modest in inland areas beneath mainly cold-based glaciers. The BuchanBuchan palaeosurfaceBuchan palaeosurface shares many characteristics with crystalline platforms inside and outside the limits of PleistocenePleistocene glaciation elsewhere in Europe.