The Lincolnshire Limestone Formation is a geological formation in
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 ...
, part of the
Inferior Oolite Group
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 ...
of the (
Bajocian
In the geologic timescale, the Bajocian is an age and stage in the Middle Jurassic. It lasted from approximately 170.3 Ma to around 168.3 Ma (million years ago). The Bajocian Age succeeds the Aalenian Age and precedes the Bathonian Age.
Stratig ...
) Middle
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), 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 J ...
strata of 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 b ...
.
It was formed around 165 million years ago, in a shallow, warm sea on the margin of the
London Platform and has
estuarine beds above and below it. The maximum known thickness is 40.2 metres, at around TF9730, while four kilometres further west it is 18.3 metres thick at its outcrop in the upper
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 Chelms ...
valley. It fades out in the south, around
Kettering
Kettering is a market and industrial town in North Northamptonshire, England. It is located north of London and north-east of Northampton, west of the River Ise, a tributary of the River Nene. The name means "the place (or territory) of Ket ...
in
Northamptonshire
Northamptonshire (; abbreviated Northants.) is a county in the East Midlands of England. In 2015, it had a population of 723,000. The county is administered by
two unitary authorities: North Northamptonshire and West Northamptonshire. It is ...
.
There are two sub-divisions, the Upper and Lower Lincolnshire Limestone Members respectively. The dividing marker is the 'Crossi' bed which is distinguished by the fossils of ''Acanthothris crossi'' it contains. The Crossi bed forms the top of the Lower Lincolnshire limestone. The bottom of the Lower Lincolnshire limestone has some of the characteristics of the underlying
Lower Estuarine Series
{{Unreferenced, date=December 2009
The Lower Estuarine Series, also called in more modern publications, the Grantham Formation, is a relatively complex but generally thin set of geological strata which are usually considered as a group. It forms a ...
, in that it tends to contain more than usual amounts of sand. A stone from this part of the formation which was commercially exploited is the
Collyweston stone slate
The Collyweston Slater pub in Collyweston with a Collyweston slate roof
Collyweston stone slate is a traditional roofing material found in central England.
It is not a proper slate but a limestone found in narrow beds. It is considerably heav ...
which was used for roofing for several centuries. It is now largely replaced in new work by concrete imitations.
Much of the rest of the Lower Lincolnshire limestone is
oolitic. It formed in warm, shallow seas where evaporation concentrated the dissolved
calcium carbonate and wave action rolled the precipitated material into tiny balls. It takes its name from its similarity to the hard
roe
Roe ( ) or hard roe is the fully ripe internal egg masses in the ovaries, or the released external egg masses, of fish and certain marine animals such as shrimp, scallop, sea urchins and squid. As a seafood, roe is used both as a cooking, coo ...
of fish.
See also
*
Oolite
Oolite or oölite (''egg stone'') is a sedimentary rock formed from ooids, spherical grains composed of concentric layers. The name derives from the Ancient Greek word for egg (ᾠόν). Strictly, oolites consist of ooids of diameter 0.25–2 ...
*
List of types of limestone
This is a list of types of limestone arranged according to location. It includes both formal stratigraphic unit names and less formal designations.
Africa Egypt
*Tura limestone, used for the Great Pyramid casing stones
*Mokattam limestone; Gr ...
*
Collyweston stone slate
The Collyweston Slater pub in Collyweston with a Collyweston slate roof
Collyweston stone slate is a traditional roofing material found in central England.
It is not a proper slate but a limestone found in narrow beds. It is considerably heav ...
*
Castle Bytham Quarry
Castle Bytham quarry is a disused quarry located close to the centre of the village of Castle Bytham, Lincolnshire, England. It is famous for the exposure of ''Laeviuscula'' Zone ammonite fauna has allowed the dating of the Upper Lincolnshire lim ...
References
Bibliography
* Hains, B.A. & Horton, A. ''British Regional Geology Central England 3rd edn. (1969) {{ISBN, 0-11-880088-4
Limestone
Stratigraphy of the United Kingdom
Geography of Lincolnshire
Bajocian Stage
Jurassic System of Europe