glacial erratics

glacial stratigraphy

Dissected drumlin, Red Banks, Shapinsay


Ice Age Westray

Glacial Deposition

Two main groups of landforms are recognised that result from deposition by ice:

  • glacial forms, deposited directly from ice
  • glacifluvial forms, deposited by meltwater

Examples from both groups of landforms are represented on Orkney. These landforms may be also be classified in terms of their position relative to the former glacier, as subglacial, englacial, supraglacial, marginal and proglacial landforms.

Glacial deposition is largely confined to low-lying areas on Orkney, where thicknesses of till may exceed 10 m. The glacial deposits drape the landscape, smoothing its outlines. Ice-marginal features are largely unrecognised outside Hoy and the glacial landforms relate mainly to the passage of the last ice sheet. Locally, multiple till sequences occur but it is uncertain if any predate the last ice sheet.