Lateglacial

Wag

 

Ellanmore (ND 237370)

Significance: organic deposits that record the vegetation of this part of Caithness between 15 and 11 thousand years ago

This section on the Reisgill shows a simple sequence of deposits, comprising from the base

  1. Devonian flagstone
  2. A rip-block till derived from glacial erosion of the bedrock
  3. Shelly till of the Forse Till
  4. A lower periglacial slope deposit derived from the shelly till
  5. The Ellanmore Peat
  6. An upper periglacial slope deposit derived from the shelly till on which the modern soil is developed

The sequence indicates that after glaciation, the till was soliflucted downslope, probably under cold conditions, in two separate periods. During an intervening warm phase, peat accumulated at the site which has yielded a single radiocarbon date of 12290 50 yr.

This warm phase belongs to the Lateglacial Interstadial. Sedges and grasses dominated the vegetation, with some crowberry and birch. Conditions appear to have been relatively dry in this part of Caithness compared to other parts of Scotland (Hall and Whittington, 1989).

The periglacial slope deposits are typical of reworked till deposits than occur across Caithness. the upper unit at Ellanmore shows frost-shattered flagstone clasts and erected pebbles.