The Chitarwata Formation is a
geological 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 ...
in western
Pakistan
Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
, made up of
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...
and early
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
terrestrial
fluvial
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluviog ...
facies
In geology, a facies ( , ; same pronunciation and spelling in the plural) is a body of rock with specified characteristics, which can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formatio ...
. The sediments were deposited in coastal
depositional environment
In geology, depositional environment or sedimentary environment describes the combination of physical, chemical, and biological processes associated with the deposition of a particular type of sediment and, therefore, the rock types that will be ...
s (
estuarine
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...
,
strandplain and
tidal flat
Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal fl ...
s) when Pakistan was partly covered by the
Tethys Ocean
The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents ...
.
Paleomagnetic
Paleomagnetism (or palaeomagnetismsee ), is the study of magnetic fields recorded in rocks, sediment, or archeological materials. Geophysicists who specialize in paleomagnetism are called ''paleomagnetists.''
Certain magnetic minerals in rock ...
data indicates an age range of around 28 to 17 million years ago, with its base in the
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...
, and its upper boundary, where it meets the overlying
Vihowa Formation, of the
Early Miocene
The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages.
The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was prece ...
.
Together with the Vihowa Formation, the Chitarwata Formation records the
sedimentation
Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...
of the Himalayan
foreland basin
A foreland basin is a structural basin that develops adjacent and parallel to a mountain belt. Foreland basins form because the immense mass created by crustal thickening associated with the evolution of a mountain belt causes the lithospher ...
during the collision of the Indian and Asian tectonic plates, the transition from
marginal marine
Marginal may refer to:
* ''Marginal'' (album), the third album of the Belgian rock band Dead Man Ray, released in 2001
* ''Marginal'' (manga)
* '' El Marginal'', Argentine TV series
* Marginal seat or marginal constituency or marginal, in polit ...
to
fluvial
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluviog ...
environments, and the
rise
Rise or RISE may refer to:
Arts, entertainment, and media Fictional entities
* '' Rise: The Vieneo Province'', an internet-based virtual world
* Rise FM, a fictional radio station in the video game ''Grand Theft Auto 3''
* Rise Kujikawa, a video ...
of the
Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
.
Fossil content
The Chitarwata Formation has provided a wealth of terrestrial mammal fossils of the late
Paleogene
The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...
and early
Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...
, or
Tabenbulakian The Tabenbulakian age is a period of geologic time (28.4–23.03 Ma) within the Oligocene Epoch of the late Paleogene Period and Miocene Epoch of the early Neogene Period, used more specifically with Asian Land Mammal Ages.
It follows the Hsand ...
; the last of the
Asian land mammal age
The Asian land mammal ages, acronym ALMA, establish a geologic timescale for prehistoric Asian fauna beginning 58.7 Mya during the Paleogene and continuing through to the Miocene ( Aquitanian) (23.03 Ma). These periods are referred to as ages, sta ...
s (ALMA).
Among many others, the following fossils are reported from the formation:
[Chitarwata Formation]
at Fossilworks
Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...
.org
Mammals
* ''
Anthracotherium adiposum'', ''A. bugtiense'', ''A. silistrense''
* ''
Asiadelphis akbarbugtii''
* ''
Atavocricetodon paaliense''
* ''
Baluchimys barryi'', ''B. chaudryi'', ''B. ganeshapher''
* ''
Brachypotherium fatehjangense''
* ''
Bugtilemur mathesoni''
* ''
Bugtimeryx pilgrimi''
* ''
Bugtimys zafarullahi''
* ''
Bugtipithecus inexpectans''
* ''
Bugtitherium grandincisivum''
* ''
Buzdartherium gulkirao''
* ''
Downsimys margolesi'', ''
D. margolisi''
* ''
Fallomus ginsburgi'', ''F. quraishyi'', ''F. razae''
* ''
Guangxilemur singsilai''
* ''
Hodsahibia azrae'', ''H. beamshaiensis'', ''H. gracilis''
* ''
Lindsaya derabugtiensis''
* ''
Lophibaluchia pilbeami''
* ''
Lophiomeryx kargilensis''
* ''
Microbunodon silistrense''
* ''
Nalameryx savagei'', ''N. sulaimani''
* ''
Paalitherium gurki''
* ''
Parabrachyodus hyopotamoides''
* ''
Paraceratherium bugtiense
''Paraceratherium'' is an extinct genus of hornless rhinoceros. It is one of the largest terrestrial mammals that has existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered ...
''
* ''
Paraentelodon sp.''
* ''
Phileosimias brahuiorum
''Phileosimias'' ("''Eosimias'' ally") is an extinct genus of primates with two species, ''P. kamli'' and ''P. bahuiorum'', that are believed to be amongst the early simians.
Marivaux ''et al.'' announced in 2005 their discovery of fossils of t ...
'', ''P. kamali''
* ''
Primus cheemai''
* ''
Prokanisamys arifi''
* ''
Progiraffa exigua''
* ''
Pseudocricetodon nawabi''
* ''
Sivameryx palaeindicus''
* ''
Spanocricetodon sulaiman''
* ''
Zindapiria quadricollis''
* ''
Deinotherium
''Deinotherium'' was a large elephant-like proboscidean that appeared in the Middle Miocene and survived until the Early Pleistocene. Although superficially resembling modern elephants, they had notably more flexible necks, limbs adapted to a mo ...
sp.''
;Reptiles
* ''
Astorgosuchus bugtiensis''
;Fish
* ''
Carcharhinus balochenisis'', ''
C. perseus''
* ''
Cretolamna twiggensis''
* ''
Hemiprisris heteropleurus''
* ''
Nebrius obliquum''
References
Further reading
* S. Adnet, P. -O. Antoine, S. R. Hassan Baqri, J. Crochet, L. Marivaux, J. Welcomme, and G. Métais. 2007. New tropical carcharhinids (chondrichthyes, Carcharhiniformes) from the late Eocene–early Oligocene of Balochistan, Pakistan: Paleoenvironmental and paleogeographic implications. ''Journal of Asian Earth Sciences'' 30(2):303-323
* G. Métais, P.-O. Antoine, S. R. H. Baqri, M. Benammi, J.-Y. Crochet, D. Franceschi, L. Marivaux and J.-L. Welcomme. 2006. New remains of the enigmatic cetartiodactyl ''Bugtitherium grandincisivum'' Pilgrim, 1908, from the upper Oligocene of the Bugti Hills (Balochistan, Pakistan). ''Naturwissenschaften'' 93(7):348-355
* E. H. Lindsay, L. J. Flynn, I. U. Cheema, J. C. Barry, K. Downing, A. R. Rajpar, and S. M. Raza. 2005. Will Downs and the Zinda Pir Dome. ''Palaeontologia Electronica'' 8(1):19A:1-18
* L. Marivaux, P.-O. Antoine, S. R. H. Baqri, M. Benammi, and Y. Chaimanee. 2005. Anthropoid primates from the Oligocene of Pakistan (Bugti Hills): Data on early anthropoid evolution and biogeography. ''Proceedings of the National Academy of Sciences'' 102(24):8436-8441
* P.-O. Antoine, J.-L. Welcomme, L. Marivaux, I. Baloch, M. Benammi and P. Tassy. 2003. First record of Paleogene Elephantoidea (Mammalia, Proboscidea) from the Bugti Hills of Pakistan. ''Journal of Vertebrate Paleontology'' 23(4):977-980
* J.-L. Welcomme and L. Ginsburg. 1997. Mise en évidence de l'Oligocène sur le territoire des Bugti (Balouchistan, Pakistan). Comptes Rendus de l'Académie des Sciences, Série IIA 325(12):999-1004
* L.J. Flynn, L.L. Jacobs, and I.U. Cheema. 1986. Baluchimyinae, A New Ctenodactyloid Rodent Subfamily from the Miocene of Baluchistan. ''American Museum Novitates'' 2841:1-58
External links
Palaeontologia Electronica
{{Protected areas of Pakistan
Geologic formations of Pakistan
Neogene System of Asia
Paleogene System of Asia
Rupelian Stage
Chattian Stage
Aquitanian (stage)
Burdigalian
Sandstone formations
Shale formations
Fluvial deposits
Fossiliferous stratigraphic units of Asia
Paleontology in Pakistan
Formations