Eocene Volcanics in South-east England

Abstract

IN Britain the contrast between the geology of the Tertiary Volcanic Province of northern Ireland and western Scotland and the Tertiary Sedimentary Province of south-eastern England is very marked. In the English Lower Eocene, the familiar London Clay was deposited in the south-western part of a larger marine “North Sea Basin”1, and on the eastern side of this “London Clay” deposits are known in Denmark, north-western Germany, Netherlands and Belgium. In Denmark, however, a conspicuous series of marine volcanic ashbeds, interbedded with diatomaceous rock, is seen in the Lower “London Clay” of Jutland2,3, and is known from many borings in north-western Germany4. A thin marginal ashfall is preserved subsurface in the northern Netherlands, which is also in the lower part of the Lower Eocene5.