: ''This article describes the

geology Geology () is a branch of natural science concerned with Earth and other Astronomical object, astronomical objects, the features or rock (geology), rocks of which it is composed, and the processes by which they change over time. Modern geology ...

of the

ceremonial county The counties and areas for the purposes of the lieutenancies, also referred to as the lieutenancy areas of England and informally known as ceremonial counties, are areas of England to which lords-lieutenant are appointed. Legally, the areas i ...

Lincolnshire Lincolnshire (abbreviated Lincs.) is a Counties of England, county in the East Midlands of England, with a long coastline on the North Sea to the east. It borders Norfolk to the south-east, Cambridgeshire to the south, Rutland to the south-we ...

. Besides the modern administrative county, it includes the

unitary authority A unitary authority is a local authority responsible for all local government functions within its area or performing additional functions that elsewhere are usually performed by a higher level of sub-national government or the national governmen ...

areas of

North Lincolnshire North Lincolnshire is a unitary authority area in Lincolnshire, England, with a population of 167,446 in the 2011 census. The borough includes the towns of Scunthorpe, Brigg, Haxey, Crowle, Epworth, Bottesford, Kirton in Lindsey and Bar ...

and

North East Lincolnshire North East Lincolnshire is a Unitary authority area with borough status in Lincolnshire, England. It borders the borough of North Lincolnshire and districts of West Lindsey and East Lindsey. The population of the district in the 2011 Census w ...

.'' The geology of Lincolnshire in eastern

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 ...

largely consists of an easterly dipping succession of

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ...

age

sedimentary rock Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

s, obscured across large parts of the county by unconsolidated deposits dating from the last few hundred thousand years of the present

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million year ...

Period.

Triassic

The oldest rocks exposed at or near the surface of Lincolnshire are the

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicat ...

s and

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from '' shale'' by its lack of fissility (parallel layering).Blatt, H., and R.J. Tracy, 1996, ''Petrology.' ...

s of the early

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest per ...

Sherwood Sandstone Group The Sherwood Sandstone Group is a Triassic lithostratigraphic group (a sequence of rock strata) which is widespread in Britain, especially in the English Midlands. The name is derived from Sherwood Forest in Nottinghamshire which is underlain by r ...

. Rocks from this and the overlying

Mercia Mudstone The Mercia Mudstone Group is an early Triassic lithostratigraphic group (a sequence of rock strata) which is widespread in Britain, especially in the English Midlands – the name is derived from the ancient kingdom of Mercia which corresponds to ...

and

Penarth Penarth (, ) is a town and Community (Wales), community in the Vale of Glamorgan ( cy, Bro Morgannwg), Wales, exactly south of Cardiff city centre on the west shore of the Severn Estuary at the southern end of Cardiff Bay. Penarth is a weal ...

groups occur in the northwest of the county and along its western border but are generally concealed beneath a thick cover of recent deposits.

Jurassic

A range of rocks from the

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

Period occur within a broadly north-south outcrop which tapers markedly northwards from

the Fens The Fens, also known as the , in eastern England are a naturally marshy region supporting a rich ecology and numerous species. Most of the fens were drained centuries ago, resulting in a flat, dry, low-lying agricultural region supported by a ...

to the banks of the

Humber The Humber is a large tidal estuary on the east coast of Northern England. It is formed at Trent Falls, Faxfleet, by the confluence of the tidal rivers Ouse and Trent. From there to the North Sea, it forms part of the boundary between ...

around Whitton and Winteringham. The lowermost and most westerly are the early Jurassic mudstones and

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 w ...

s of the

Lias Group The Lias Group or Lias is a lithostratigraphic unit (a sequence of rock strata) found in a large area of western Europe, including the British Isles, the North Sea, the Low Countries and the north of Germany. It consists of marine limestones, sh ...

, overlain in turn by the middle Jurassic

Inferior Oolite The Inferior Oolite is a sequence of Jurassic age sedimentary rocks in Europe. It was deposited during the Middle Jurassic.Weishampel, David B; et al. (2004). "Dinosaur distribution (Middle Jurassic, Europe)." In: Weishampel, David B.; Dodson, Pet ...

and Great Oolite groups which comprise a mix of limestones, mudstones and sandstones and then the late Jurassic mudstones, limestones, sandstones and

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, ...

s of the

Corallian Group 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. It is a hard variety of "coral rag". Building stones from this ge ...

and succeeding West Walton Formation. Lincoln Edge is formed by the Oolite Group limestones.

Cretaceous

The

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

sequence begins with the

Wealden Group The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimenta ...

limestones, mudstones, sandstones and siltstones which occur from Gibraltar Point in a band which narrows northwestwards to the

Caistor Caistor is a town and civil parish in the West Lindsey district of Lincolnshire, England. As its name implies, it was originally a Roman castrum or fortress. It lies at the north-west edge of the Lincolnshire Wolds, on the Viking Way, an ...

area. To their east, and stratigraphically above them, are the sandstones of the

Lower Greensand Group The Lower Greensand Group is a geological unit present across large areas of Southern England. It was deposited during the Aptian and Albian stages of the Early Cretaceous. It predominantly consists of sandstone and unconsolidated sand that were ...

and beyond them the

Chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. C ...

which gives rise to the Lincolnshire Wolds and extends to the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...

coast but is obscured along the coastal margin.

Quaternary

A wide range of superficial deposits have been laid down across the county in the last couple of million years. Lincolnshire was over-ridden by glacial ice on at least one occasion, that of the

Anglian glaciation The Anglian Stage is the name used in the British Isles for a middle Pleistocene glaciation. It precedes the Hoxnian Stage and follows the Cromerian Stage in the British Isles. The Anglian Stage is correlated to Marine Isotope Stage 12 (MIS 12), ...

which left

glacial till image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...

across much of the county. In the course of the more recent end- Devensian ice age,

ice heading south penetrated inland as far as the eastern slopes of the Lincolnshire Wolds and into the embayment of The Wash. A further tongue of ice advanced southwards from the

Vale of York The Vale of York is an area of flat land in the northeast of England. The vale is a major agricultural area and serves as the main north–south transport corridor for Northern England. The Vale of York is often supposed to stretch from the R ...

into the northwestern corner of the county as far as the

Isle of Axholme The Isle of Axholme is a geographical area in England: a part of North Lincolnshire that adjoins South Yorkshire. It is located between the towns of Scunthorpe and Gainsborough, both of which are in the traditional West Riding of Lindsey, an ...

. Glacial sands and gravels occur in places along the eastern margin of the Wolds. There are extensive spreads of river, estuarine and coastal

alluvium Alluvium (from Latin ''alluvius'', from ''alluere'' 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. ...

along the North Sea Coast and around the Wash as far inland as

Crowland Crowland (modern usage) or Croyland (medieval era name and the one still in ecclesiastical use; cf. la, Croilandia) is a town in the South Holland district of Lincolnshire, England. It is situated between Peterborough and Spalding. Crowland ...

in the south and roughly along the line of the South Forty-Foot Drain. Alluvium also covers the flat floors of the Trent,

Witham Witham () is a town in the county of Essex in the East of England, with a population ( 2011 census) of 25,353. It is part of the District of Braintree and is twinned with the town of Waldbröl, Germany. Witham stands between the city of Che ...

and Ancholme rivers whilst river terrace sands and gravels are widespread around

Woodhall Spa Woodhall Spa is a former spa Village and civil parish in Lincolnshire, England, on the southern edge of the Lincolnshire Wolds, south-west of Horncastle, Lincolnshire, Horncastle, west of Skegness, east-south-east of Lincoln, Lincolnshire, Li ...

, in the Trent valley and towards Lincoln, along the course of the

River Slea The River Slea is a tributary of the River Witham, in Lincolnshire, England. In 1872 the river was described as "a never-ending source of pure water", and was a trout river renowned throughout the East coast of England. But in the late 1960s, t ...

and south of

Sleaford Sleaford is a market town and civil parish in the North Kesteven district of Lincolnshire, England. Centred on the former parish of New Sleaford, the modern boundaries and urban area include Quarrington to the south-west, Holdingham to the no ...

through Bourne to

Market Deeping Market Deeping is a market town and civil parish in the South Kesteven district of Lincolnshire, England, on the north bank of the River Welland and the A15 road. The population of the town at the 2011 census was 6,008. History The town's mar ...

. Areas of blown sand occur at

Donna Nook Donna Nook is a point on the low-lying coast of north Lincolnshire, England, north of the village of North Somercotes and south of Grimsby. The area, a salt marsh, is used by a number of Royal Air Force stations in Lincolnshire for bombing pra ...

and inland across an area centred upon

Scunthorpe Scunthorpe () is an industrial town and unparished area in the unitary authority of North Lincolnshire in Lincolnshire, England of which it is the main administrative centre. Scunthorpe had an estimated total population of 82,334 in 2016. A ...

but extending southeast beyond

Market Rasen Market Rasen ( ) is a town and civil parish within the West Lindsey district of Lincolnshire, England. The River Rase runs through it east to west, approximately north-east from Lincoln, east from Gainsborough, 14 miles (23 km) west of Lo ...

and west to the Yorkshire border.

Peat Peat (), also known as turf (), is an accumulation of partially Decomposition, decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, Moorland, moors, or muskegs. The peatland ecosystem covers and ...

is common around the fenland margin from Walcot to the Cambridgeshire border near

.British Geological Survey 1:625,000 scale geological map ''Quaternary Map of the United Kingdom South'' 1st Edn. 1977

References

{{Geology of England Geography of Lincolnshire

Triassic

Jurassic

Cretaceous

Quaternary

See also

Further reading

References