Marine geology of the atlantic continental margin of europe

Abstract

A geological reconnaissance has been made of the continental slope of western Europe between the Faeroe Isles and Lisbon by means of a 60 kJ reflexion profiler, supplemented by Boomer profiles and extensive Asdic (side-looking sonar) coverage of the continental shelf. A tentative interpretation of these profiles has been made by references to available rock samples and seismic refraction data. The first-formed continental slope deposits of the north-east Atlantic appear to be Cretaceous in age. Massive erosion (particularly of the continental shelf) preceded the Tertiary phase of downwarping which allowed upbuilding and outbuilding of the continental margin and was followed by a latest-Tertiary and Quaternary phase of important faulting, canyon erosion, slumping and deposition. This episodic evolution of the European continental margin is thought to indicate two phases of continental drift. In contrast to the ground west of the British Isles and France the steep and narrow northern and western continental margins of Iberia show only a little upbuilding and only local outbuilding. The work was done from aboard R.R.S. Discovery II or R.R.S. Discovery (with the exception of a Sparker profile obtained by H.M.T.S. Alert), the powerful profiler being used in 1965, the Asdic on many cruises between 1958 and 1967.