Emeleus, C.H. & Gyopari, M.C. 1992. British Tertiary Volcanic Province, Geological Conservation Review Series No. 4. JNCC, Peterborough, ISBN 0 412 47980 X. The original source material for these web pages has been made available by the JNCC under the Open Government Licence 3.0. Full details in the JNCC Open Data Policy
Chapter 7 Other Tertiary sites
Introduction
The British Tertiary Volcanic Province (BTVP) contains only a small proportion of the total igneous activity that occurred during the Palaeocene–Eocene opening of the North Atlantic. Within the Province, attention has been focused on the spectacular remnants of that activity in and around the central complexes and the majority of the sites described in this volume come from these areas and their immediate surroundings. Nevertheless, a number of important aspects of the igneous geology of the Province occur elsewhere and the sites described in this chapter cover them.
The NW- to NNW-oriented dyke swarms are a spectacular feature of the Province and examples of dense concentrations of dykes are described or noted close to the central complexes, for example, Kildonnan–Bennan Head, Arran and Loch Bà, Mull. The Cleveland Dyke of North Yorkshire is a far-flung, recently studied representative of the Mull swarm; this is described in the Lang-baurgh Ridge–Cliff Ridge site. Mesozoic sediments filling basins adjoining the central complexes are often intruded by dolerite sill complexes. The Shiant Isles site is an excellently exposed, well-described example which exhibits a wide range of rock types attributed to multiple injection and magmatic differentiation. This site augments the information on differentiated sills from Dippin Head, Arran and Rubha Hunish, Skye. Two further sites, St Kilda and Rockall, lie in the North Atlantic to the west of Scotland