The Stratheden Group is a

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

lithostratigraphic Lithostratigraphy is a sub-discipline of stratigraphy, the geology, geological science associated with the study of stratum, strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are ...

group A group is a number of persons or things that are located, gathered, or classed together. Groups of people * Cultural group, a group whose members share the same cultural identity * Ethnic group, a group whose members share the same ethnic iden ...

(a sequence of

rock strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ei ...

) in southern

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...

and northernmost

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 ...

. Occasionally pebbly, this red-brown and yellow

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 silicates) ...

dominated unit also contains

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, p ...

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. It is encountered in Arran in the west and across the Midland Valley to the northeastern parts of

Fife Fife (, ; gd, Fìobha, ; sco, Fife) is a council area, historic county, registration county and lieutenancy area of Scotland. It is situated between the Firth of Tay and the Firth of Forth, with inland boundaries with Perth and Kinross (i ...

in the east. The name is derived from Stratheden in Fife. The rocks of the Stratheden Group have also previously been referred to as the Upper Old Red Sandstone. It unconformably overlies a variety of other rock sequences including the

Strathmore Group The Strathmore Group is a Devonian lithostratigraphic group (a sequence of rock strata) in central Scotland. Its sandstones are interbedded with siltstones which interfinger with conglomerates. It is encountered from Arran in the west across th ...

around

Dumbarton Dumbarton (; also sco, Dumbairton; ) is a town in West Dunbartonshire, Scotland, on the north bank of the River Clyde where the River Leven flows into the Clyde estuary. In 2006, it had an estimated population of 19,990. Dumbarton was the ca ...

Stirling Stirling (; sco, Stirlin; gd, Sruighlea ) is a city in central Scotland, northeast of Glasgow and north-west of Edinburgh. The market town, surrounded by rich farmland, grew up connecting the royal citadel, the medieval old town with its me ...

and Arran and the Arbuthnott-Garvock Group in Fife and the

Kinross Kinross (, gd, Ceann Rois) is a burgh in Perth and Kinross, Scotland, around south of Perth and around northwest of Edinburgh. It is the traditional county town of the historic county of Kinross-shire. History Kinross's origins are connect ...

area.

References

* {{Refend Silurian System of Europe Geology of England Geology of Scotland Geological groups of the United Kingdom Geologic formations of the United Kingdom