A series of buried valleys situated south of the submerged Chalk outcrop of the Strait of Dover and eroded down to — 170 m n .g.f. || are recognized as infilled tunnel-valleys excavated subglacially during the Warthe Phase of the Saalian glaciation beneath an ice sheet that advanced up the English Channel from the west. Before the Saalian a Chalk ridge joined England and France. Later in the Warthe, ice withdrew from the English Channel and an ice lobe from the North Sea overrode the Chalk ridge to extend some distance down-Channel, eroding some deep NNE-SSW hollows associated with the tunnel-valleys and scouring out the present deep-water channel; this being probably the first physical opening of the Strait of Dover. The tunnel-valleys were infilled during the Eemian interglacial and finally during the Brorup interstadial as evidenced by palynological study of borehole V 050 cores. The authors propose to name the major northern buried valley described in this paper 'Fosse Dangeard’, to honour the doyen of English Channel geology, Professeur Louis Dangeard. We are happy to have received his gracious acceptance of this proposal.

Several lines of evidence for former glaciation of the English Channel are considered. These include the following major geomorphical features: (1) extensive areas of flat featureless sea bed bounded by cliffs with residual steep-sided rock masses rising about 60-150 m above them, (2) terrace forms bounded by breaks in slope or low cliffs, (3) palaeovalley systems related to the present land drainage, (4) enclosed deeps (fosses); all except (3) may be attributed to a glacial origin. The distribution of erratics on the Channel floor and in the modern and raised beaches of its coasts are attributed to widespread Saalian glaciation. This glaciation was responsible for the deposition of morainic material at Selsey and the damming-up of glacial Lake Solent. The so-called ‘100 foot raised beach’ of west Sussex is now re-interpreted as a fluvioglacial deposit laid down at the northern margin of the English Channel ice. It is thought that at the height of the Saalian glaciation mean sea-level fell to between 90 and 180 m below o.d. and that for a time the ice was grounded near the western margin of the continental shelf. Possible reconstructions of the limits and main movements of the Weichselian and Saalian ice sheets covering the British Isles and English Channel are included.

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The purpose of this paper is to review current information and opinions on the structures of the concealed Palaeozoic rocks of southeastern England and adjacent parts of northwestern Europe. The authors attempt a regional synthesis, which suggests that certain structural trends in these older rocks have been reactivated several times in the subsequent history of the area, and in some cases control the alinement of present-day surface features. We have drawn on the accumulated data of field surveys, deep boreholes and geophysical investigations carried out by the Institute of Geological Sciences, and also information obtained during the commercial search for coal and oil. The results of marine gravity measurements recently made by I.G.S. and the Admiralty in the eastern English Channel and southern North Sea are presented for the first time. Similarly, we are glad to include data from M r P. L. Rumsby’s recent analyses of fault trends in the Kent collieries, for the National Coal Board. Reference is also made to some of the results of the Channel Tunnel site investigation 1964 5 (Destombes & Shephard-Thorn 1971). Published literature and maps form the basis of our remarks on northern Europe, though we are grateful to Destombes for unpublished information on the Boulonnais.

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