Aymestry Limestone
{{short description|Geologic formation in England}}
{{Use dmy dates|date=April 2022}}
{{Infobox rockunit
| name = Aymestry Limestone
| image = Limestone Exposure near Munslow, Shropshire - geograph.org.uk - 676613.jpg
| caption = Aymestry Limestone in a quarry, Shropshire
| type = Formation
| age = Silurian
| period = Silurian
| prilithology = Limestone
| otherlithology = Mudstone, sandstone
| namedfor = Aymestrey
| namedby =
| region = Welsh Marches, West Midlands, Coalbrookdale & Malvern Hills
| country = {{UK}}
| coordinates =
| unitof =
| subunits =
| underlies = Upper Ludlow Shales Group
| overlies = Lower Ludlow Shales Group
| thickness = Up to {{convert|48|m|ft|abbr=on}}
| extent =
| area =
| map =
| map_caption =
}}
The Aymestry Limestone is a fossiliferous limestone of Gorstian age (Upper Silurian) deposited in a warm shallow sea near the eastern margin of the Iapetus Ocean. It occurs in England in the Ludlow Group, between the Upper and Lower Ludlow Shales.{{cite web | url=http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=AL | title=Aymestry Limestone Formation | publisher=British Geological Survey | work=The BGS Lexicon of Named Rock Units | accessdate=20 February 2016}} It derives its name from Aymestrey (sic), Herefordshire, where it may be seen on both sides of the River Lugg. It is well developed in the neighbourhood of Ludlow (it is sometimes called the Ludlow limestone) and occupies a similar position in the Ludlow shales at Woolhope, the Abberley Hills, May Hill and the Malvern Hills.{{sfn|Chisholm|1911}}
Description
In lithological character, this limestone varies greatly; in one place it is a dark grey, somewhat crystalline limestone, elsewhere it passes into a flaggy, earthy or shaly condition, or even into a mere layer of nodules. When well developed it may reach 50 ft. in thickness in beds of from 1 to 5 ft.; in this condition it naturally forms a conspicuous feature in the landscape because it stands out by its superior hardness from the soft shales above and below.{{sfn|Chisholm|1911}}
The most common fossil is Pentamerus knightii, which is extremely abundant in places. Other brachiopods, corals and trilobites are present, and are similar to those found in the Wenlock limestone.{{sfn|Chisholm|1911}}
See also
{{Portal|Earth sciences|England|Paleontology}}
References
{{reflist}}
Further reading
- {{Citation |chapter-url=http://www.british-history.ac.uk/report.aspx?compid=22855 |chapter=Introduction |editor=C R J Currie |author=A P Baggs |author2=G C Baugh |author3=D C Cox |author4=Jessie McFall |author5=P A Stamper |publisher=Institute of Historical Research |date=1998 |title=A History of the County of Shropshire: Volume 10: Munslow Hundred (part), The Liberty and Borough of Wenlock |pages=1–6 |accessdate=22 March 2013 }}
- {{Citation|url=http://www.silurian.com/geology/salop.htm |title=The Silurian in Shropshire}}
External links
- {{EB1911|wstitle=Aymestry Limestone|volume=3|pages=73–74}}
- {{cite web|title= Fossilworks: Gateway to the Paleobiology Database|author= ((Various Contributors to the Paleobiology Database))|url= https://www.fossilworks.org|access-date= 17 December 2021}}
{{Clear}}
Category:Geologic formations of England
Category:Silurian southern paleotemperate deposits
Category:Limestone formations of the United Kingdom
Category:Fossiliferous stratigraphic units of Europe
Category:Paleontology in the United Kingdom
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