Early Pleistocene

Middle Pleistocene

Late Pleistocene

Quaternary of the northern North Sea

North Sea drill core

Quaternary of the West Shetland Platform

The record of sedimentation in the North Atlantic provides key information on the pulse of glaciation in the Northern Hemisphere. Thin Quaternary sediment on the inner part of the West Shetland shelf thickens to the west. Maximum sediment thicknesses of 800 m occur on the outer shelf edge and mid-slope on the continental slope. During the last 3-4 Ma the edge of the continental shelf has advanced westward due to rapid sedimentation.

Between 0.75 and 2.5 Ma, water depths at the continual margin were shallow, reflecting low global sea level. A wedge of deltaic and shallow sands developed, with dropstones from icebergs in a few horizons indicating periodic glaciation of land areas bordering the North Atlantic and general cooling of the ocean. The first direct evidence of glaciation comes from around 440 ka when an Elsterian ice sheet advanced to the shelf edge. Subsequent ice advances in the Saalian and Early and Late Weichselian also extended to the shelf edge, implying that sea level and rates of ice berg calving were fundamental controls on the westward extent of the Shetland ice sheet (Stoker et al., 1993).