Lower Carboniferous rocks crop out over a wide area in Britain and form areas of spectacular coastal and upland scenery encompassing the Midland Valley of Scotland, the Pennines, Lake District, north and south Wales, the Mendips and south-west England. Economically, they provide an important source of raw materials for the construction industry, some are host rocks for metallogenic mineral deposits, and others have potential as source or reservoir rocks for hydrocarbons.

 

This volume details the character and scientific importance of Lower Carboniferous sedimentary rock formations exposed at 145 of the finest Earth heritage sites in Britain. These formations were deposited between 354 and 323 million years ago, when the piece of Earth's crust we now call 'Britain' lay close to the equator and towards the southern margin of the ancient continent of 'Laurussia'. The formations mostly formed in shallow, tropical seas that were teeming with life, in environments such as reefs, lagoons, tidal flats and offshore sand bars developed above flat-lying shelf areas or gently dipping carbonate ramps. At this time an open ocean lay to the south of Britain in front of an advancing southern continent, Gondwana. Towards the end of the Carboniferous Period, Laurussia and Gondwana collided to form the supercontinent of 'Pangaea', a process that caused the widespread deformation of Lower Carboniferous formations throughout Britain, but particularly in south-west England.

 

The sites described form part of a national GCR site network that records the geological history of Britain during Early Carboniferous times and provide a framework for the national and international correlation of Lower Carboniferous sequences. These sequences are particularly significant in understanding the evolution of ancient carbonate platforms and many have been used to define sedimentary models that are used in exploration for important economic resources.

 

The GCR sites are described in chapters organized by palaeogeographic area, and each chapter begins with an introduction that considers the history of research, the regional stratigraphical and structural setting, and the GCR site coverage in each area.