The Hopeman Sandstone Formation is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

.The BGS Lexicon of Named Rock Units: Hopeman Sandstone Formation
/ref> It preserves fossil footprints and body

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

from the

Guadalupian The Guadalupian is the second and middle Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico an ...

Epoch in the Late

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

, to the Early

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

,Walker, AD. 1973. The age of Cuttie's Hillock Sandstone (Perm-Triassic) of the Elgin Area. Scottish Journal of Geology 9:177-183. It preserves fossils and fossil footprints from various extinct animals such as

pareiasaurs Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with osteoderms which covered large areas of the body. They first appeared in southern Pangea during the Middle Perm ...

and

dicynodonts Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivores that typically bore a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, t ...

, which are collectively often referred to as the

Elgin Reptiles Elgin Reptiles is the name given to the Permian and Triassic fossils found in the sandstone deposits in and around the town of Elgin, in Moray, Scotland. They are of historical and scientific importance, and many of the specimens are housed in the ...

. The formation, named for the village of

Hopeman Hopeman (, ) is a seaside village in Moray, Scotland, it is situated on the coast of the Moray Firth, founded in 1805 to house and re-employ people displaced during the Highland clearances. According to the 2011 census, Hopeman has a populati ...

, lies unconformably over the

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 ...

Upper

Old Red Sandstone Old Red Sandstone, abbreviated ORS, is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the eastern seaboard of North America. It ...

, and it underlies the waterlain sandstones of the Burghead Sandstone Formation. It represents a windswept dune landscape. The Hopeman Sandstones were previously referred to as the Cutties Hillock Sandstone, Quarry Wood Sandstones, Sandstones of Hopeman, and Hopeman-Cummingstown Sandstone, but these names have since been superseded.

Lithology

The Hopeman Sandstone Formation is predominantly composed of fine- to coarse-grained yellowish sand with well rounded grains, mostly deposited as wind-blown

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

s, but occasionally deposited by sheet floods. Basal beds are pebbly and the unit varies, exhibiting large-scale

crossbedding In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. The Principle ...

to fine rarely contorted

lamination Simulated flight (using image stack created by μCT scanning) through the length of a knitting needle that consists of laminated wooden layers: the layers can be differentiated by the change of direction of the wood's vessels Shattered windshi ...

s. Some beds are

friable In materials science, friability ( ), the condition of being friable, describes the tendency of a solid substance to break into smaller pieces under stress or contact, especially by rubbing. The opposite of friable is indurate. Substances tha ...

, while others hard and

siliceous Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant ...

Origin of names

The name ''Cutties Hillock'' is believed to derive from the

Scottish Gaelic Scottish Gaelic (, ; Endonym and exonym, endonym: ), also known as Scots Gaelic or simply Gaelic, is a Celtic language native to the Gaels of Scotland. As a member of the Goidelic language, Goidelic branch of Celtic, Scottish Gaelic, alongs ...

, meaning 'hill brow of the hunting'.Benton MJ and Walker AD. 1985. Palaeoecology, taphonomy and dating of Permo-Triassic reptiles from Elgin, North-East Scotland. Palaeontology 28:207-234 The name first appeared in print after the discovery of the

in 1884. Although now formally considered part of the Hopeman Sandstone Formation, the Cuttie's Hillock Sandstone is still used to refer to the inland outcroppings of Hopeman Sandstone, particularly at Quarry Wood near Elgin. Benton and Walker (1985) argue that the name Cuttie's Hillock Sandstone should be retained to distinguish these fossil-bearing beds from those on the coast, which have only yielded footprints and very few body fossils.

Paleobiota

The

pareiasaur Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with osteoderms which covered large areas of the body. They first appeared in southern Pangea during the Middle Per ...

Elginia ''Elginia'' is an extinct genus of pareiasaurid known from the Late Permian of Scotland and China. It was named for the area around Elgin, Moray, Elgin in Scotland, which has yielded many fossils referred to as the Elgin Reptiles. Discovery ...

'' and

dicynodont Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivores that typically bore a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, t ...

s '' Geikia'' and '' Gordonia'' are known from the formation, the fossils are preserved as hollow internal moulds within the sandstone.

References

External links

* Permian Scotland Sandstone formations Permian System of Europe Changhsingian Geologic formations of Scotland {{Scotland-stub

Lithology

Origin of names

Paleobiota

See also

References

External links