Calciferous sandstone is an obsolete geological term relating to

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

at the base of the

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

formation, below the coal measures. The rocks of this formation are now considered part of the

Inverclyde Group The Inverclyde Group is a Carboniferous lithostratigraphic group (a sequence of rock strata) in southern Scotland and northernmost England. The name is derived from Inverclyde. The rocks of the Inverclyde Group have also previously been referred ...

and

Strathclyde Group The Strathclyde Group is a Group (geology), geological group found in the Central Lowlands, Midland Valley of Scotland. It preserves fossils of Visean, the Visean age (early Carboniferous Period (geology), period). See also * List of fossilife ...

. Typically this geological sequence, as in the Touch Hills and Fintry Hills to the west of

Stirling Stirling (; ; ) is a City status in the United Kingdom, city in Central Belt, central Scotland, northeast of Glasgow and north-west of Edinburgh. The market town#Scotland, market town, surrounded by rich farmland, grew up connecting the roya ...

contains a mixture of

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

s and

sedimentary rock Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or de ...

s, including

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

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.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, ...

, and lies unconformably on top of older

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

strata.

References

Carboniferous geology {{UK-geologic-formation-stub