GCR block - Westphalian (WPH)

Westphalian

Block Description

UK map showing distribution of GCR sites of GCR block WPH
Distribution of GCR sites of GCR block Westphalian

The GCR sites selected for this GCR Block represent the British geological record of Earth history from about 310 to 300 million years ago (Ma). This interval is part of Late Carboniferous Period (the Carboniferous Period spans from about 354 to 292 Ma). Underlying rocks formed during Namurian time (see NAM-E-WL).

There has been much confusion as to the exact meaning of the term ‘Upper Carboniferous’. In northern Europe, it has been taken to include all of the Namurian, Westphalian and Stephanian series, as this represents an interval of largely fluvio-deltaic clastic rocks, which can be readily separated from the mainly marine shelf limestones of the underlying Viséan. It is placed just above the base of the Chokierian Stage in the European classification. For convenience, the base of the Chokierian Stage is used in the GCR as an approximation to the lower limit of the Lower Carboniferous subsystem.

Now, all of the eight stages of the Late Carboniferous Series, the Chokierian, Alportian, Kinderscoutian, Marsdenian, Yeadonian, Langsettian, Duckmantian and Bolsovian are defined by stratotypes in this country. The Langsettian, Duckmantian and Bolsovian stages form the Westphalian Series.

Namurian rocks in Britain can be roughly equated to the informal term ‘Millstone Grit’, which is overlain by the ‘Coal Measures’ and underlain by the Dinantian ‘Carboniferous Limestone’.

Outcrop pattern

Britain has some of the best-exposed sequences of non-marine Upper Carboniferous strata anywhere in Europe. Nowhere else has such extensive coastal exposures of these beds, as can be seen in Pembrokeshire, Northumberland, Cumbria and Fife. Even outside of Europe, one would struggle to find comparable coastal exposures, at least within the palaeoequatorial belt, with the possible exception of Nova Scotia in Canada (e.g. Joggins Bank, Point Aconi). Britain also has many natural, inland exposures. In the Westphalian, South Wales stands unrivalled (at least in Europe) for its well exposed sequences of mainly non-marine, coal-bearing strata; for example, this is the only place to have a more or less continuously exposed section through the Langsettian, Duckmantian and Bolsovian strata (Cwm Gwrelych–Nant Llyn Fach).

There is considerable variation in the lithostratigraphical development of the Upper Carboniferous strata of Britain, and different areas often have their own set of formations. Only ‘the Productive Coal Formation’ (the mainly Westphalian, grey, coal-bearing deposits) has a reasonably wide distribution. However, there is an underlying pattern of lithofacies recognizable over much of the country, and this is recognized here as five groups listed as follows.

• Culm Group

• Yoredale Group

• Millstone Grit Group

• Passage Group

• Coal Measures Group

Palaeoenvironment and palaeogeography

The Upper Carboniferous of Britain was formed in an elongate belt of deposition lying between Poland and Ireland, that marks the contact-zone between the Gondwana and Laurasia continental plates. Originally separated by deep ocean (the ‘Proto-Tethys’), the Gondwana plate progressively drifted north relative to the Laurasia plate during Late Palaeozoic times. By Late Carboniferous time, the deep ocean had totally disappeared, and eventually the collision caused significant uplift and deformation of the Laurasian foreland. This tectonic episode is termed the ‘Variscan (or Hercynian) Orogeny’ (see VAR-STR-SW; VAR-STR-WM). However, between the times of ocean closure and basin inversion, a complex set of localized, synorogenic basins developed on the foreland.

There are four main mechanisms that have been proposed for how these basins were generated: (1) the northwards subduction of Gondwana under Laurasia, (2) transtension due to east–west mega-shear along the Gondwana-Laurasia plate boundary, (3) nappe loading due to the northwards migration of the Variscan front, and (4) north–south rifting and ocean spread due to the opening of a ‘Proto-Atlantic’ Ocean.

The result has been five discrete areas of deposition, separated by areas of non-deposition and sometimes erosion. These are, from south to north, Sabrina, the Wales–Brabant Barrier and the Southern Uplands Massif.

(1) The Culm Trough in south-west England. This was a shallow marine basin that was progressively filled during the Namurian by northerly derived deltaic sediments. Basin inversion and tectonic deformation here was rather earlier than in the rest of Britain, probably sometime in the middle part of the Westphalian Epoch.

(2) The Kent Coalfield, which is effectively a western extension of the Franco-Belgian Basin. This coalfield is known only through boreholes and underground mine workings, therefore as there is no exposure.

(3) The area immediately south of the Wales–Brabant Barrier, including principally South Wales, the Forest of Dean and the Bristol–Somerset coalfields. Like the Culm Trough, the Namurian strata are characterized by the progressive infill of a shallow marine basin by deltaic sediment, although it seems to have been ‘less marine’ than the Culm deposits. During the early and middle Westphalian times (up to the middle Bolsovian), deposition was characteristically in a fluvio-delatic regime, with extensive peat deposits. In late Westphalian times, however, uplift mainly to the south resulted in the influx of mainly arenaceous fluvial deposits (the Pennant Formation).

(4) The area between the Wales–Brabant Barrier and the Southern Uplands Massif, and including the northern English Midlands, the Pennines, and northern England. Again, the Namurian is characterized by mainly northerly-derived deltaic deposits filling a shallow marine basin, and the lower and middle Westphalian by fluvio-deltaic deposition. Unlike further south, however, there is no evidence of major fluvial deposits in upper Westphalian strata, except in the southern margins of the area. Instead, the progressive development of Variscan movement resulted in the formation of red beds such as the Etruria Formation.

(5) The Midland Valley of Scotland. The general facies development here is similar to the area south of the Southern Uplands Massif, with predominantly arenaceous deposits in the Namurian, coal-bearing deposits in the lower Westphalian and red beds in the upper Westphalian. However, marine influence was significantly reduced, with the result that marine bands are fewer and less well developed. Also volcanicity was a much greater influence, both as an influence on basin configuration, and on sedimentation itself (e.g. the Ayrshire Bauxitic Clay Formation).

GCR site selection

For the Upper Carboniferous stratigraphy of Britain sites were selected according to palaeogeographically defined GCR networks

• Culm Trough

• South Wales

• Forest of Dean and Severn coalfields

• Bristol-Somerset Basin

• English Midlands

• North Wales

• Millstone Grit of the Central Province

• Coal Measures of the Pennine Basin

• Northern England

• Scottish Basin

Although the relatively common invertebrate fossils do not have a separate selection category in the GCR in their own right, the scientific importance of many stratigraphy sites lies in their fossil content. Therefore, some of the GCR sites are selected specifically for their fossil fauna, which facilitates stratal correlation and enables the interpretation of the environments in which the animals lived. Moreover, some sites have international significance because they have yielded fossils that are the ‘type’ material for a taxonomic group.

In contrast to the manner in which most invertebrate fossils are represented in the GCR, fossils of vertebrates, arthropods (except trilobites) and terrestrial plants do have their own dedicated selection categories, owing to the relative rarity of the fossil material. See APD; C-P-FA; PAZ-PALBOT; PALENT.

Palaeontology

Five main groups of fossils have been used for biostratigraphical work in the British Upper Carboniferous strata: ammonoids (goniatites), conodonts, non-marine bivalves, microspores and plant macrofossils.

Most stratigraphical correlations in the British Upper Carboniferous are based on biostratigraphical criteria. However, there are two types of ‘marker horizon’ available in these strata that provide valuable, abiotic means of establishing time-planes.

The most widely used are the marine bands. During the Late Carboniferous, Britain saw a progressive change from predominantly marine to predominantly non-marine conditions, and the preserved sedimentary sequence can be interpreted in terms of the interplay between these two broad environments.

The second type of ‘marker horizons’ consists of cineritic tonsteins, which were the result of volcanic ash-falls.


Volume Introduction

Westphalian


Site List

Your selection found 73 GCR sites. Sites are sorted alphabetically by country, local authority and then by site name -
CodeNameCountryLocal AuthorityGrid RefGCR Site Account
2162Bradgate BrickworksEnglandBarnsley, Doncaster and RotherhamSK413935Not available
2065Carlton Main BrickworksEnglandBarnsley, Doncaster and RotherhamSE411081Not available
772Stairfoot BrickworksEnglandBarnsley, Doncaster and RotherhamSE381050Not available
2394Elland Bypass CuttingEnglandCalderdale, Kirklees and WakefieldSE119203Not available
2395Honley Station CuttingEnglandCalderdale, Kirklees and WakefieldSE146125Not available
2234Nostell Brickyard QuarryEnglandCalderdale, Kirklees and WakefieldSE403170Not available
3023Clovelly CoastEnglandCornwall and Isles of ScillySS314255Not available
1651Webster's Clay PitEnglandCoventrySP341806Not available
3021Abbotsham CoastEnglandDevon CCSS403269Not available
3022Bude CoastEnglandDevon CCSS213174Not available
3025Shipload BayEnglandDevon CCSS248276Not available
1747Brewin's Canal SectionEnglandDudley and SandwellSO937877Not available
1746Doulton's Clay Pit, NethertonEnglandDudley and SandwellSO936871Not available
1744Halesowen Road CuttingEnglandDudley and SandwellSO971836Not available
1745Ketley Clay PitEnglandDudley and SandwellSO897887Not available
2396Jockie's SykeEnglandEast CumbriaNY424756Not available
773Duckmanton Railway CuttingEnglandEast DerbyshireSK424704Not available
638River Doe LeaEnglandEast DerbyshireSK459692Not available
1424Meezy HurstEnglandGloucestershireSO638089Not available
1421Oakenhill Railway CuttingEnglandGloucestershireSO631080Not available
1423Puddlebrook QuarryEnglandGloucestershireSO646183Not available
2391AshcloughEnglandGreater Manchester NorthSD763063Not available
2251Low Side BrickworksEnglandGreater Manchester NorthSD942042Not available
2278River Tonge, Mill HillEnglandGreater Manchester NorthSD725096Not available
2062Ravenhead BrickworksEnglandLancashire CCSD515040Not available
1579Bickley WoodEnglandNorth and North East Somerset, South GloucestershireST644703Not available
1429Cattybrook BrickpitEnglandNorth and North East Somerset, South GloucestershireST592833Not available
1414Portishead Pier SectionEnglandNorth and North East Somerset, South GloucestershireST475776Not available
1580Winterbourne Railway CuttingEnglandNorth and North East Somerset, South GloucestershireST651799Not available
2938Cresswell and Newbiggin ShoresEnglandNorthumberlandNZ304855Not available
2397Tynemouth to Seaton SluiceEnglandNorthumberlandNZ345760Not available
774Little DonEnglandSheffieldSE222004Not available
2233Neepsend Railway CuttingEnglandSheffieldSK344896Not available
2064Neepsend Railway CuttingEnglandSheffieldSK353890Not available
2051Stannington RuffsEnglandSheffieldSK305891Not available
2161Wharncliffe CragsEnglandSheffieldSK300972Not available
1373Alveley Grindstone QuarryEnglandShropshire CCSO758848Not available
1865Benson's BrookEnglandShropshire CCSO593772Not available
2163Cheswardine Canal CuttingEnglandShropshire CCSJ697307Not available
1866Cornbrook DingleEnglandShropshire CCSO602758Not available
2160Ambergate QuarryEnglandSouth and West DerbyshireSK359518Not available
2243Goyt's MossEnglandSouth and West DerbyshireSK018715Not available
2184Ridgeway QuarryEnglandSouth and West DerbyshireSK358514Not available
3010Gospel End Road CuttingEnglandStaffordshire CCSO904936Not available
2063Metallic TileriesEnglandStaffordshire CCSJ840498Not available
2393Wear River BankEnglandSunderlandNZ362579Not available
2156New Hadley BrickworksEnglandTelford and WrekinSJ683118Not available
2839Kingsbury BrickworksEnglandWarwickshireSP220987Not available
2250Saltom BayEnglandWest CumbriaNX962165Not available
1743Eyemore Railway CuttingEnglandWorcestershireSO767792Not available
2392Joppa ShoreScotlandCity of EdinburghNT321734Not available
2834East Wemyss to Buckhaven CoastScotlandClackmannanshire and FifeNT339964Not available
2835Byre BurnScotlandDumfries and GallowayNY389778Not available
2823Lagrae BurnScotlandDumfries and GallowayNS705153Not available
2822Polhote Burn and Polneul BurnScotlandDumfries and GallowayNS688123Not available
2836Corrie ForeshoreScotlandEast Ayrshire and North Ayrshire MainlandNS026432Not available
2837Dunaskin GlenScotlandEast Ayrshire and North Ayrshire MainlandNS454088Not available
2824Inninmore BayScotlandLochaber, Skye and Lochalsh and Argyll and the IslandsNM710423Not available
3338Sevenacres MillScotlandNorth AyrshireNT335445Not available
1422Cwm Gwrelych and Nant Llyn Fach StreamsWalesBRIDGEND AND NEATH PORT TALBOTSN891064Not available
1426Earlswood Road Cutting and Ferryboat Inn QuarriesWalesBRIDGEND AND NEATH PORT TALBOTSS729946Not available
1425Blaenrhondda Road CuttingWalesCENTRAL VALLEYSSN927016Not available
1415Brynmawr Road CuttingWalesGWENT VALLEYSSO197121Not available
1412Coed-y-DarrenWalesGWENT VALLEYSST240921Not available
2050Trehir QuarryWalesGWENT VALLEYSST154897Not available
1427Wern Ddu ClaypitWalesGWENT VALLEYSST168857Not available
1417Nant LlechWalesPOWYSSN834127Not available
1419PontneddfechanWalesPOWYSSN900079Not available
1420Cwm TwrchWalesSOUTH WEST WALESSN755125Not available
1418Nolton Haven CoastWalesSOUTH WEST WALESSM861173Not available
1428Tenby–Saundersfoot CoastWalesSOUTH WEST WALESSN136016Not available
1416Wiseman's Bridge–Amroth CoastWalesSOUTH WEST WALESSN148062Not available
1413Penllergaer Railway CuttingWalesSWANSEASS619999Not available
Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access. Search Again