The North Sea basin

The North Sea basin originated as a consequence of relaxation of the mid-Miocene Alpine orogenic stress field, with a subsidence rate of approximately 0.35 m/1000 years over the past 10 million years (Ziegler & Louwerens, 1979; Cameron et al., 1992). As a result, there is a thick sequence of Tertiary and Quaternary sediments, with up to 1000 metres of Quaternary sediments in the central graben of the basin (Caston, 1977). This sequence of sediments preserves evidence for repeated glaciation during the Quaternary, with evidence for extensive glaciations during the Elsterian, Saalian and Weichselian, as well as fragmentary evidence for glaciation during the Menapian (Bijlsma, 1981; Gibbard, 1988; Sejrup et al., 1987). This report synthesises published information from the entire offshore region of the North Sea (Fig. 1), from 52°N to the continental shelf edge, and includes new micromorphological data that adds significant new understanding to the extent and dynamics of the Weichselian ice sheets.