Softer sandy deposits occur within the Corallian, found for example at Faringdon, Shellingford and Hatford in Oxfordshire, where the sands and gravels are extensively quarried.
The Corallian Limestone aquifer is present at outcrop in Yorkshire and in the Cotswolds.[2] In Yorkshire it consists of limestones and grits up to about 110 m thick, thinning to about 20 m towards the south of the region, where the limestones are progressively replaced by clay. It is typically well jointed and gives rise to numerous springs. Here it yields up to 15 L/sec. In the Cotswolds the aquifer is up to 40 m thick, give yields of 5 to 10 L/sec, with water quality becoming increasingly saline down dip as the aquifer becomes confined in the Wessex Basin.
corallian, group, corallian, limestone, geologic, group, england, predominantly, coralliferous, sedimentary, rock, laid, down, oxfordian, stage, jurassic, hard, variety, coral, building, stones, from, this, geological, structure, tend, irregular, shape, often,. The Corallian Group or Corallian Limestone is a geologic group in England It is predominantly a coralliferous sedimentary rock laid down in the Oxfordian stage of the Jurassic 1 It is a hard variety of coral rag Building stones from this geological structure tend to be irregular in shape It is often found close to seams of Portland Limestone e g Abbotsbury in Dorset England It is a younger limestone than its near neighbour the Oolitic as found in the Cotswolds in Gloucestershire It is laterally equivalent to and interfingers with units of the Ancholme Group Corallian GroupStratigraphic range Oxfordian 163 153 Ma PreꞒ Ꞓ O S D C P T J K Pg NCorallian strata exposed near Bran PointTypeGroupSub unitsCleveland Basin Lower Calcareous Grit Formation Coralline Oolite Formation Upper Calcareous Grit Formation Dorset to Oxfordshire Hazelbury Bryan Formation Kingston Formation Stanford Formation Dorset to Wiltshire Stour Formation Clavellata Formation Sandsfoot FormationUnderliesKimmeridge Clay Formation Ampthill Clay Faringdon SandOverliesOxford Clay Formation West Walton FormationThickness100 m 330 ft LithologyPrimarylimestone marl sandstone siltstone mudstone LocationRegionEnglandCountry United KingdomExtentDorset to Oxfordshire North YorkshireA ridge of Corallian Limestone rises above the Vale of Avon and the Thames Valley in its Oxfordshire stretch The Oxfordshire Corallian ridge is an escarpment holding back the hanging valley that is the Vale of White Horse and its hardness forced the River Thames to take a wide northern detour to cut through the low ridge at Oxford High points along the ridge are Cumnor Hurst and Wytham Hill The outcrop known as Headington stone was quarried at Headington Quarry on the outskirts of Oxford and used for many of the historic University buildings there Hilly outcrops above this corallian ridge composed of Lower Greensand occur at Badbury Hill Faringdon Folly Hill and Boars Hill Softer sandy deposits occur within the Corallian found for example at Faringdon Shellingford and Hatford in Oxfordshire where the sands and gravels are extensively quarried The Corallian Limestone aquifer is present at outcrop in Yorkshire and in the Cotswolds 2 In Yorkshire it consists of limestones and grits up to about 110 m thick thinning to about 20 m towards the south of the region where the limestones are progressively replaced by clay It is typically well jointed and gives rise to numerous springs Here it yields up to 15 L sec In the Cotswolds the aquifer is up to 40 m thick give yields of 5 to 10 L sec with water quality becoming increasingly saline down dip as the aquifer becomes confined in the Wessex Basin In England Corallian Limestone is to be found in Dorset 3 Wiltshire Oxfordshire Buckinghamshire Cambridgeshire Lincolnshire and Yorkshire The most noted scholar of the Corallian strata of England was the geologist W J Arkell 1904 1958 See also edit nbsp Wikisource has the text of the 1911 Encyclopaedia Britannica article Corallian List of types of limestone List of fossiliferous stratigraphic units in EnglandReferences edit Corallian Group The BGS Lexicon of Named Rock Units British Geological Survey Retrieved 14 December 2014 The Corallian Limestone as an aquifer British Geological Survey Retrieved 9 December 2016 Fifehead Wood Management Plan 2010 2015 PDF Woodland Trust p 6 Retrieved 10 April 2013 permanent dead link External links editVarious Contributors to the Paleobiology Database Fossilworks Gateway to the Paleobiology Database Retrieved 17 December 2021 nbsp This article about a specific stratigraphic formation in the United Kingdom is a stub You can help Wikipedia by expanding it vte This article related to the Jurassic period is a stub You can help Wikipedia by expanding it vte nbsp This England related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Corallian Group amp oldid 1179915970, wikipedia, wiki, book, books, library,
