Chitarwata Formation

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Chitarwata Formation
Stratigraphic range: Early Oligocene (Tabenbulakian)-Early Miocene
~28–17  Ma
Type Geological formation
Sub-unitsBugti Member
Overlies Vihowa Formation
Lithology
Primary Sandstone
Other Claystone
Location
Coordinates 29°00′N69°00′E / 29.0°N 69.0°E / 29.0; 69.0
Approximate paleocoordinates 19°24′N67°42′E / 19.4°N 67.7°E / 19.4; 67.7
Region Balochistan
CountryFlag of Pakistan.svg  Pakistan
Type section
Named for Chitarwata
Pakistan relief location map.jpg
Orange pog.svg
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Yellow pog.svg
Chitarwata Formation (Pakistan)

The Chitarwata Formation is a geological formation in western Pakistan, made up of Oligocene and early Miocene terrestrial fluvial facies. The sediments were deposited in coastal depositional environments (estuarine, strandplain and tidal flats) when Pakistan was partly covered by the Tethys Ocean.

Contents

Paleomagnetic data indicates an age range of around 28 to 17 million years ago, with its base in the Oligocene, and its upper boundary, where it meets the overlying Vihowa Formation, of the Early Miocene.

Together with the Vihowa Formation, the Chitarwata Formation records the sedimentation of the Himalayan foreland basin during the collision of the Indian and Asian tectonic plates, the transition from marginal marine to fluvial environments, and the rise of the Himalayas.

Fossil content

The Chitarwata Formation has provided a wealth of terrestrial mammal fossils of the late Paleogene and early Neogene, or Tabenbulakian; the last of the Asian land mammal ages (ALMA).

Among many others, the following fossils are reported from the formation: [1]

Mammals

Artiodactyl

Anthracothere
Anthracotheriidaes of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Anthracotherium A. adiposum
A. bugtiense
A. silistrense
Bugtitherium B. grandincisivum
Microbunodon M. silistrense
Parabrachyodus P. hyopotamoides
Sivameryx S. palaeindicus
Entelodonts
Entelodonts of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Paraentelodon P. sp.
Giraffid
Giraffids of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Progiraffa P. exigua
lophiomerycids
lophiomerycidaes of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Nalameryx N. savagei
N. sulaimani
Lophibaluchia L. pilbeami
Lophiomeryx L. kargilensis
Ruminants
Ruminants of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Bugtimeryx B. pilgrimi
Paalitherium P. gurki

Perissodactyl

Paraceratheriidae
Paraceratheriidaes of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
BuzdartheriumB. gulkirao
Paraceratherium P. bugtiense
Rhinocerotidae
Rhinocerotidaes of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Aprotodon A. smithwoodwardi
Brachypotherium B. fatehjangense
Epiaceratherium E. magnum
Pleuroceros P. blanfordi

Marsupials

Marsupials of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Asiadidelphis A. akbarbugtii

Rodents

Rodents of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Atavocricetodon A. paaliense
Baluchimys B. barryi
B. chaudryi,
B. ganeshapher
Bugtimys B. zafarullahi
Downsimys D. margolisi
Fallomus F. ginsburgi
F. quraishyi
F. razae
Hodsahibia H. azrae
H. beamshaiensis
H. gracilis
LindsayaL.derabugtiensis
PrimusP. cheemai
P. microps
Spanocricetodon S. sulaiman
Prokanisamys P. arifi
P. kowalskii
Pseudocricetodon P. nawabi
Zindapiria Z. quadricollis

Primates

Primates of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Bugtilemur B. mathesoni
Bugtipithecus B. inexpectans
Guangxilemur Guangxilemur singsilai
Phileosimias P. brahuiorum
P. kamali

Proboscidean

Proboscideans of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Deinotherium D. sp.

Reptiles

Reptiles of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
AsifcrocoA. retraiA crocodilian.
Astorgosuchus A. bugtiensis A crocodilian.

Fish

Fishs of the Chitarwata Formation
GenusSpeciesLocationMaterialsNotesImage
Carcharhinus C. balochenisis
C. perseus
Cretolamna Cretolamna twiggensis
Hemipristis H. heteropleurus
Nebrius N. obliquum

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References

  1. Chitarwata Formation at Fossilworks.org

Further reading