Moradi Formation
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The Moradi Formation is a geological formation in
Niger ) , official_languages = , languages_type = National languagesLate Permian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...
age. It is informally divided into three subunits. The lower portion of the formation consists of red
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. ...
, with muddy calcareous
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) ...
and quartz-granlule conglomerate present as
lenses A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...
. The middle portion consists of muddy
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 ...
in thick beds interbedded with red
argillaceous Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al2 Si2 O5( OH)4), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces. Clay minerals ...
sandstone. The lower two thirds of the upper portion of the formation consist of red siltstone intercalated with channel
lag Lag, or similar, may refer to: Lag * Łąg, Poland * Lag (company), a French guitar maker * Lag (cue sports), a brief pre-game competition to determine which player will go first * Latency (engineering), a slower response time in computing, commu ...
intraformational conglomerates, while the upper third consists of
barchan A barchan or barkhan dune (from Kazakh бархан ) is a crescent-shaped dune. The term was introduced in 1881 by Russian naturalist Alexander von Middendorf, based on their occurrence in Turkestan and other inland desert regions. Barchans ...
oid shaped lenses of conglomeratic sandstone with
ventifact A ventifact (also wind-faceted stone, windkanter) is a rock that has been abraded, pitted, etched, grooved, or polished by wind-driven sand or ice crystals. These geomorphic features are most typically found in arid environments where there is lit ...
s. These facies are indicatived of deposition under
arid A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...
conditions, with less than of annual rainfall in the Central Pangean desert, with annual temperatures of , but with ephemeral water presence including lakes.


Fossil content

The formation is known for its fossils, including the
temnospondyl Temnospondyli (from Greek language, Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order (biology), order of small to giant tetrapods—often considered Labyrinthodontia, primitive amphi ...
s '' Nigerpeton'' and '' Saharastega, ''the
pareiasaur 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, ...
''
Bunostegos ''Bunostegos'' ("knobbly kullroof") is an extinct genus of pareiasaur parareptile from the Late Permian of the Agadez Region in Niger. The type species, ''Bunostegos akokanensis'', was named from the Moradi Formation in 2003. It was a cow-size ...
, ''the captorhinid '' Moradisaurus'', as well as a large indeterminate
gorgonopsid Gorgonopsia (from the Greek Gorgon, a mythological beast, and 'aspect') is an extinct clade of sabre-toothed therapsids from the Middle to Upper Permian roughly 265 to 252 million years ago. They are characterised by a long and narrow skull ...
.''''
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, typicall ...
s, widespread in other contemporary deposits, appear to be absent, with previous reports being in error.'''' The flora of the formation includes indeterminate voltzian conifers.


References

{{reflist Geologic formations of Niger Permian System of Africa Changhsingian Conglomerate formations Mudstone formations Sandstone formations Shale formations Fluvial deposits Ichnofossiliferous formations Permian southern paleotemperate deposits Paleontology in Niger