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. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...

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

Guadalupian The Guadalupian is the second and middle series/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 and Texas, and dates between 272.95 ± ...

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 251.9 Mya. It is the last ...

, to the Early

Triassic The Triassic ( ) is a geologic period and system (stratigraphy), system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Year#Abbreviations yr and ya, Mya), to the beginning of the Jurassic Period 201.36 ...

,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 scutes which covered large areas of the body. They first appeared in southern Pangea during the Middle Permian ...

and

dicynodonts Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivorous animals with a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, typicall ...

, 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 th ...

. The formation, named for the village of

Hopeman Hopeman ( sco, Houpmin, gd, Hudaman) 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 ...

, lies unconformably over the Devonian Upper

Old Red Sandstone The Old Red Sandstone 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 northeastern seaboard of North America. It also exte ...

, 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 dunes, 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 origina ...

to fine rarely contorted

lamination Lamination is the technique/process of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, sound insulation, appearance, or other properties from the use of the differing materia ...

s. Some beds are

friable Friability ( ), the condition of being friable, describes the tendency of a solid substance to break into smaller pieces under duress or contact, especially by rubbing. The opposite of friable is indurate. Substances that are designated hazardous, ...

, while others hard and

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

Origin of names

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

Scottish Gaelic Scottish Gaelic ( gd, Gàidhlig ), also known as Scots Gaelic and Gaelic, is a Goidelic language (in the Celtic branch of the Indo-European language family) native to the Gaels of Scotland. As a Goidelic language, Scottish Gaelic, as well ...

, 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 ''

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 in Scotland, which has yielded many fossils referred to as the Elgin Reptiles. Discovery The type sp ...

'' and

dicynodont Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivorous animals with a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, typic ...

s ''

Geikia ''Geikia'' is an extinct genus of dicynodont therapsids from the late Permian. The abundance and diversity of dicynodonts during this period, combined with incomplete or inadequately prepared specimens, have led to challenges in determining relat ...

'' 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 {{Scotland-stub

Lithology

Origin of names

Paleobiota

See also

References

External links