Related Research Articles
The geological structure of Great Britain is complex, resulting as it does from a long and varied geological history spanning more than two billion years. This piece of the Earth's crust has experienced several episodes of mountain building or 'orogenies', each of which has added further complexity to the picture.
The Bronnant Fault is a geological fault affecting the lower Palaeozoic rocks of the counties of Ceredigion and Pembrokeshire in West Wales. The feature is mapped over part of its length as the Bronnant Fault Zone and is closely associated with the Glandyfi Lineament, a similarly aligned zone of faulting and folding. The rocks of the Aberystwyth Grits Group dating from the Llandovery epoch of the Silurian period thicken markedly to the west of the fault suggesting it was active at the time of their deposition. North of Lledrod its alignment is affected by cross-cutting east–west faults, including the Ystwyth Fault Zone. Its alignment is sub-parallel to the coast of Cardigan Bay thus curving from a north–south alignment in the north through a northeast–southwest alignment until it merges with broadly east–west aligned faults in northeast Pembrokeshire.
The Flintshire Coalfield in north-east Wales is one of the smaller British coalfields. It is in the county of Flintshire and extends from the Point of Ayr in the north, along the Dee Estuary through Connah's Quay to Caergwrle in the south. A small part extends onto the Wirral i.e. English coast of the estuary at Neston, Cheshire which was the site of a coalmine for a period. The coal-bearing strata continue southwards of Caergwrle as the Denbighshire Coalfield. Together the two coalfields are known as the North Wales Coalfield.
The Cumberland Coalfield is a coalfield in Cumbria, north-west England. It extends from Whitehaven in the south to Maryport and Aspatria in the north.
The Leicestershire and South Derbyshire Coalfield in the English Midlands is one of the smaller British coalfields. The two areas are sometimes separately referred to as the South Derbyshire Coalfield and the Leicestershire Coalfield. All of the worked coal seams are contained within the Lower and Middle Coal Measures which are of Upper Carboniferous age.
The Brora Coalfield is a coalfield on the east coast of Sutherland in northern Scotland. The 'Brora Main' is a 1m to 1.5m thick seam which has been mined in the Brora area. It is unusual amongst British coalfields in being of Jurassic age rather than Carboniferous. The first seams to be worked were those exposed along the North Sea coast though inland mining began in the early nineteenth century. Mining continued until the 1970s; its principal market being the nearby brickworks.
The Machrihanish Coalfield is a coalfield on the Kintyre peninsula in southwest Scotland. It is one of the smallest British coalfields. With the exception of a thin coal beneath the Lyoncross Limestone in the overlying Upper Limestone Formation, all of the coal-bearing strata are found within the Limestone Coal Formation, a subdivision of the Clackmannan Group; all being strata of Namurian age. There are numerous seams of which the Main Coal is the principal one, being some 3 to 4m thick. A further, higher seam known as the Kilkivan Coal has also been worked. The full sequence is:
The Canonbie Coalfield is a small and largely concealed coalfield at Canonbie in the south of Scotland. A comprehensive survey by Peach and Horne was published in 1903. Canonbie colliery was worked until 1920, and another mine at Archerbeck continued until 1942.
The Midgeholme Coalfield is a coalfield in Midgeholme, on the border of Cumbria with Northumberland in northern England. It is the largest of a series of small coalfields along the south side of the Tyne Valley and which are intermediate between the Northumberland and Durham Coalfields to the east and the Cumberland Coalfield to the west. Like the other small coalfields to its east, this small outlier of the Coal Measures at Midgeholme occurs on the Stublick-Ninety Fathom Fault System, a zone of faults defining the northern edge of the Alston Block otherwise known as the North Pennines. It is recorded that coal was being mined at Midgeholme in the early seventeenth century. In the 1830s coal trains were being hauled from Midgeholme Colliery along the Brampton Railway by Stephenson's Rocket. The early workings have left a legacy of spoil heaps, bell pits, shafts and adits. There is no current coal production. However in January 2014, Northumberland County Council gave planning permission for the open-cast extraction of 37,000 tonnes of coal at Halton Lea Gate. This may open the way for other applications to mine the coalfield. In 1990 a proposal to mine reserves of 60,000 tonnes of good-quality coal at Lambley, Northumberland was rejected, but the prospect for a successful application has now changed, since the Planning Inspector allowed the development to proceed at Halton Lea Gate on appeal.
The Warwickshire coalfield extends between Warwick and Tamworth in the English Midlands. It is about 25 miles (40 km) from north to south and its width is around half that distance. Its western margin is defined by the 'Western Boundary Fault'. In the northeast it abuts against steeply dipping shales of Cambrian age. The larger part of the outcrop at the surface consists of the Warwickshire Group of largely coal-barren red beds. Until its closure in 2013, the Daw Mill mine near Arley within the coalfield, was Britain's biggest coal-producer in the 21st century.
The geology of West Sussex in southeast England comprises a succession of sedimentary rocks of Cretaceous age overlain in the south by sediments of Palaeogene age. The sequence of strata from both periods consists of a variety of sandstones, mudstones, siltstones and limestones. These sediments were deposited within the Hampshire and Weald basins. Erosion subsequent to large scale but gentle folding associated with the Alpine Orogeny has resulted in the present outcrop pattern across the county, dominated by the north facing chalk scarp of the South Downs. The bedrock is overlain by a suite of Quaternary deposits of varied origin. Parts of both the bedrock and these superficial deposits have been worked for a variety of minerals for use in construction, industry and agriculture.
The Exmoor Group is a late Devonian to early Carboniferous lithostratigraphic group in southwest England whose outcrop extends from Croyde in north Devon east across Exmoor to Minehead in west Somerset. The group comprises the following formations :
The Appleby Group is a lithostratigraphical term referring to the succession of Permian Period aeolian and fluviatile rock strata which occur in northwest England and beneath the Irish Sea in the United Kingdom.
The Trawden Limestone Group is a lithostratigraphical term referring to the succession of limestone rock strata which occur in parts of Lancashire and neighbouring Yorkshire, northern England in the United Kingdom laid down within the Chadian to Brigantian sub-Stages of the Carboniferous Period.
The geology of Northumberland in northeast England includes a mix of sedimentary, intrusive and extrusive igneous rocks from the Palaeozoic and Cenozoic eras. Devonian age volcanic rocks and a granite pluton form the Cheviot massif. The geology of the rest of the county is characterised largely by a thick sequence of sedimentary rocks of Carboniferous age. These are intruded by both Permian and Palaeogene dykes and sills and the whole is overlain by unconsolidated sediments from the last ice age and the post-glacial period. The Whin Sill makes a significant impact on Northumberland's character and the former working of the Northumberland Coalfield significantly influenced the development of the county's economy. The county's geology contributes to a series of significant landscape features around which the Northumberland National Park was designated.
References
Maps
- British Geological Survey 2007, Bedrock Geology UK North, 1:625,000 scale geological map, British Geological Survey, Keyworth, Notts (UK (north) 625K)
- British Geological Survey 1996 Tectonic map of Britain, Ireland and Adjacent Areas 1996, Pharaoh TC et al. (compilers), 1:1,500,000 British Geological Survey, Keyworth, Notts (Tect B&Ire 1:1500K)
- British Geological Survey, various of 1:50,000 scale geological maps of Scotland, British Geological Survey, Keyworth, Notts (Sc no.)
- British Geological Survey 'Classic Areas' series; Glencoe, 1:25,000 scale geological map, British Geological Survey, Keyworth, Notts (Glencoe:25K)
- British Geological Survey 'Classic Areas' series; Skye Central Complex, 1:25,000 scale geological map, British Geological Survey, Keyworth, Notts (Skye Central Complex Bedrock 25k)
Books
- Trewin, NH (ed) 2002. The Geology of Scotland, (4th edn) The Geological Society, London (Trewin (ed) 2002)
- British Regional Geology: Orkney and Shetland, British Geological Survey, Nottingham (BGS:BRG1)
- British Regional Geology: Northern Highlands of Scotland, British Geological Survey, Nottingham (BGS:BRG2)
- Emeleus CH & Bell BR 2005, British Regional Geology; The Palaeogene volcanic districts of Scotland (4th edn) British Geological Survey, Nottingham (BGS:BRG3)
- Goodenough, K.M. & Krabbendam, M. 2011 A Geological Excursion Guide to the North-west Highlands of Scotland, Edinburgh Geological Society, ISBN 978-1-905267-53-8 (G & K 2011)
- Grieg, D.C. 1971. British Regional Geology: The South of Scotland (3rd edn) British Geological Survey, Nottingham (BGS:BRG6). Full text of second edition (1948) available at the Internet Archive.
- Stone et al. 2012. British Regional Geology: South of Scotland (Fourth edn) British Geological Survey, Nottingham (BGS:BRG6ednIV)
- British Regional Geology: Northern England, British Geological Survey, Nottingham (BGS:BRG7)
- Lintern, B.C. & Floyd, J.D. 2000 Geology of the Kirkcudbright-Dalbeattie District memoir of the British Geological Survey, sheets 5W, 5E and part of 6W (Scotland) (Mem Sc 5W, 5E & pt6W)
- Whitbread, K. Ellen, R. Callaghan, E. Gordon, J.E. and Arkley, S. 2015 East Lothian Geodiversity Audit BGS Open Report OR/14/063 192pp (ELGA)
