Ardersier Peninsula and the Ardersier Silts Formation

T he Ardersier Peninsula is formed mainly of rhythmically bedded silts and sands of probable glaciomarine origin ( Ardersier Silts Fm ), locally capped by till, and trimmed on the north and west sides by Late Devensian (late - glacial) and Holocene (postglacial or Flandrian) raised shorelines. The peninsula rises to an altitude of about 40 m OD, but the highest marine features are shingle ridges at 28 -31 m OD, below which lie late -glacial shoreline fragments at altitudes of 28.5 m, 26.6 m, 21 -21.6 m and 18.5 m OD (Firth, 1984, 1989b) (Fig. 30). The prominent ‘Main Postglacial Cliffline’ borders raised shingle beach ridges at about 11 m OD (see cover photo). This prominent abandoned cliff line was generally thought to have been created by marine erosion during the Holocene, but it is now considered to have been formed mainly in the cold climate of the Loch Lomond Stadial (Younger Dryas) and that the feature was only trimmed during the mid - Holocene ( Sissons, 1981a). The peninsula includes important evide nce for a significant glacial readvance within the Inverness Firth, termed the Ardersier Readvance by J.S. Smith (1968, 1977) or the Ardersier Oscillation by Merritt et al. (1995).