The Lilstock Formation is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. It preserves bivalve,

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

and other invertebrate fossils, as well as fossil fish of '' Agkistracanthus mitgelensis'' and the basal theropod dinosaur '' Newtonsaurus cambrensis'' dating back to the Rhaetian of the

Triassic The Triassic ( ) is a geologic period and system (stratigraphy), system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Year#Abbreviations yr and ya, Mya), to the beginning of the Jurassic Period 201.36 ...

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

White Lias

The White lias is a rare, fine-grained form of

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

from the late

period, occurring only in certain parts of

Somerset ( en, All The People of Somerset) , locator_map = , coordinates = , region = South West England , established_date = Ancient , established_by = , preceded_by = , origin = , lord_lieutenant_office =Lord Lieutenant of Somerset , lord_ ...

and infrequently in

Warwickshire Warwickshire (; abbreviated Warks) is a county in the West Midlands region of England. The county town is Warwick, and the largest town is Nuneaton. The county is famous for being the birthplace of William Shakespeare at Stratford-upon-Av ...

. It gets the name ‘lias’ from the quarrymen's dialect for ‘layers’, referring to its natural state when quarried. White lias is part of the Langport Member of the Lilstock Formation, a multi-layered bed of stone formed from shale and limestone. At its base is a bone-bed yielding ancient marine, reptilian and ammonite fossils. White lias varies in colour from white-cream to pale grey and is traditionally used for building and flooring. Evidence of its use can be seen in manor houses, churches and cathedrals all over the UK. It is most prevalent in the Somerset towns of Midsomer Norton,

Radstock Radstock is a town and civil parish on the northern slope of the Mendip Hills in Somerset, England, about south-west of Bath and north-west of Frome. It is within the area of the unitary authority of Bath and North East Somerset. The Radstoc ...

Langport Langport is a small town and civil parish in Somerset, England, west of Somerton in the South Somerset district. The parish, which covers only part of the town, has a population of 1,081. Langport is contiguous with Huish Episcopi, a separate ...

and

Wincanton Wincanton ( or ) is a small town and electoral ward in South Somerset, southwest England. The town lies off the A303 road, a main route between London and South West England, and has some light industry. The town and electoral ward has a populati ...

. Bowdens quarry in Langport is the only supplier of white lias, and of the more commonly found

blue lias The Blue Lias is a geological formation in southern, eastern and western England and parts of South Wales, part of the Lias Group. The Blue Lias consists of a sequence of limestone and shale layers, laid down in latest Triassic and early Jurassi ...

and grey varieties.

White Lias

See also

References

Further reading