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Khuff Formation

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Khuff Formation
Stratigraphic range: Middle Permian (?Capitanian) to early Triassic
TypeGeological formation
Unit ofAkhdar Group[1]
Sub-unitsFrom youngest to oldest:[2]
  • Khartam Member
  • Midhnab Member
  • Duhaysan Member
  • Huqayl Member
  • Ash Siqqah Member
UnderliesSudair Formation[1][2]
OverliesGharif Formation[1]
Thickness
  • 171.4 m (562.2 ft) (type section)[2]
  • 1,110 m (3,641 ft) (northern Oman)[1]
Location
RegionMiddle East
Country
Type section
Named bySteineke et. al.[2]
Year defined1958[2]

The Khuff Formation is a geologic formation in Oman and Saudi Arabia.[1] It preserves fossils dating back to the Permian and early Triassic periods.[2]

Stratigraphy

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Depending on the author, various definitions and names for the members of the Khuff Formation have been proposed, which may lead to confusion. Vaslet et. al. (2005) defines the members as such (from oldest to youngest):[2]

The Al Siqqah Member is the oldest of the members, tentatively dated to the middle Permian (Capitanian). It is 35 meters thick at the type section, becoming thinner to the southeast. It has previously been referred to as the Unayzah Formation or Unayzah Member.

The Huqayl Member has been dated to the late Permian (?Wuchiapingian) based on foraminifer assemblage. It ranges from 30 to 40 meters in thickness.

The Duhaysan Member is 13.4 meters thick at Jabal Duhaysan, and is believed to be late Permian (Wuchiapingian-Changhsingian) in age.

The Midhnab Member (or Midhnab Shale) is believed to date to the Changhsingian and is about 60 meters thick in the Ad Dawadimi quadrangle.

The Khartam Member (formerly the Khartam Limestone) is the youngest member, with the lower part dating to the latest Permian and the upper part to the early Triassic.

Depositional environment

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The Khuff Formation was deposited on the outer shelf of the Arabian Platform and represents a shallow carbonate platform, with a coastline oriented northeast-southwest and facing the spreading Neotethys Ocean. The various units have been interpreted as lagoonal tidal sand flats or barrier beaches, outer-shelf conditions below storm wave base and deposition around storm wave base. The known fossil content supports the interpretation of the Khuff Formation as a marine environment. The presence of Tethyan brachiopods suggest a subtropical and warm climate, while cosmopolitan, endemic and Gondwanan brachiopod taxa indicate the area was open to outside influence, and the conodont fauna confirms a shallow marine habitat.[3][4]

Fossil content

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Fish

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Cartilaginous fish

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A large number of chondrichthyan dermal denticles are known from the formation.[3]

Cartilaginous fish reported from the Khuff Formation
Genus Species Location Stratigraphic member Material Notes Images
Amelacanthus A. cf. sulcatus Haushi-Huqf area (Oman).[3] 25 spine fragments.[3] A ctenacanth.
Anachronistidae? Gen. et. sp. indeterminate Haushi-Huqf area (Oman).[3] 2 teeth.[3] A potential anachronistid.
Cooleyella C. cf. fordi Haushi-Huqf area (Oman).[3] 2 teeth.[3] An anachronistid.
Deltodus D. aff. mercurei Haushi-Huqf area (Oman).[3] 24 tooth plates.[3] A cochliodontiform.
Eugeneodontiformes? Gen. et. sp. indeterminate Haushi-Huqf area (Oman).[3] 2 tooth crowns.[3] A likely eugeneodont.
Euselachii incertae sedis Haushi-Huqf area (Oman).[3] 10 teeth.[3] A potential protacrodontid.
Glikmanius G. culmenis Haushi-Huqf area (Oman).[3] 137 teeth.[3] A ctenacanth.
G. cf. myachkovensis Haushi-Huqf area (Oman).[3] 649 teeth.[3] A ctenacanth.
Gunnellodus G. bellistriatus Haushi-Huqf area (Oman).[3] 254 teeth.[3] A hybodont.
Khuffia K. lenis Haushi-Huqf area (Oman).[3] 79 teeth.[3] A sphenacanthid.
K. prolixa Haushi-Huqf area (Oman).[3] 27 teeth.[3] A sphenacanthid.
Nemacanthus N. sp. Haushi-Huqf area (Oman).[3] 2 dorsal spine fragments.[3] A palaeospinacid.
Omanoselache O. angiolinii Haushi-Huqf area (Oman).[3] 86 teeth.[3] A hybodont.
O. hendersoni Haushi-Huqf area (Oman).[3] 717 teeth.[3] A hybodont.
cf. O. sp. Haushi-Huqf area (Oman).[3] 14 teeth.[3] A hybodont.
cf. 'Paleozoic Genus 1' sp. Haushi-Huqf area (Oman).[3] A tooth.[3] A hybodont, potential lochidiid.
Petalodontiformes? Gen. et. sp. indeterminate Haushi-Huqf area (Oman).[3] 2 broken teeth.[3] Similar to Chomatodus.
Reesodus R. underwoodi Haushi-Huqf area (Oman).[3] 6 teeth.[3] A hybodont.
Solenodus S. cf. crenulatus Haushi-Huqf area (Oman).[3] 4 tooth plates.[3] A cochliodontiform.
Teresodus T. amplexus Haushi-Huqf area (Oman).[3] 103 teeth.[3] A hybodont.

Conodonts

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Conodonts reported from the Khuff Formation
Genus Species Location Stratigraphic member Material Notes Images
"Jinogondolella" "J." cf. altaduensis Jabal al Murayrah (Saudi Arabia).[5] Midhnab Member.[5] 1 specimen.[5] A gondolellid.

Invertebrates

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Brachiopods

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Brachiopods reported from the Khuff Formation
Genus Species Location Stratigraphic member Material Notes Images
Kotlaia K. sp. ind. Saudi Arabia.[6] Midhnab Member.[6] An articulated specimen & a dorsal valve.[6] An enteletoid.
Omanilasma O. desertica Haushi ring (Oman).[6] 29 articulated specimens.[6] A terebratulidan.
O. husseinii Oman & Saudi Arabia.[6] Midhnab Member.[6] Over 200 specimens.[6] A terebratulidan.

Cephalopods

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Cephalopods reported from the Khuff Formation
Genus Species Location Stratigraphic member Material Notes Images
Tirolonautilus T. feltgeni South of Jabal al Amshiyah (Saudi Arabia).[7] Lower Khartam Member.[7] Internal mould.[7] A tainoceratid nautiloid.
T. hoernesi East of Safra ad Dumaythiyat (Saudi Arabia).[7] Lower Midhnab Member.[7] Internal mould.[7] A tainoceratid nautiloid.

See also

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References

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  1. ^ a b c d e f Osterloff, Peter; Al-Harthy, Aida; Penney, Randall; Spaak, Pieter; Williams, Glen; Al-Zadjali, Farida; Jones, Neil; Knox, Robert; Stephenson, Michael; Oliver, Guy; Al-Husseini, Moujahed (January 2004). "Depositional sequences of the Gharif and Khuff Formations, subsurface Interior Oman". GeoArabia: 83–147.
  2. ^ a b c d e f g h Vaslet, Denis; Le Nindre, Yves-Michel; Vachard, Daniel; Broutin, Jean; Crasquin-Soleau, Sylvie; Berthelin, Martine; Gaillot, Jérémie; Halawani, Mohammed; Al-Husseini, Moujahed (2005-10-01). "The Permian-Triassic Khuff Formation of central Saudi Arabia". GeoArabia. 10 (4): 77–134. doi:10.2113/geoarabia100477. ISSN 1025-6059.
  3. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap Koot, Martha B.; Cuny, Gilles; Tintori, Andrea; Twitchett, Richard J. (2013-03-13). "A new diverse shark fauna from the Wordian (Middle Permian) Khuff Formation in the interior Haushi-Huqf area, Sultanate of Oman: CHONDRICHTHYANS FROM THE WORDIAN KHUFF FORMATION OF OMAN". Palaeontology. 56 (2): 303–343. doi:10.1111/j.1475-4983.2012.01199.x.
  4. ^ Angiolini, Lucia; Nicora, Alda; Bucher, Hugo; Vachard, Daniel; Pillevuit, Alain; Platel, Jean-Pierre; Roger, Jack; Baud, Aymon; Broutin, Jean; Al Hashmi, Haroub; Marcoux, Jean (1998-11-30). "Evidence of a Guadalupian age for the Khuff Formation of southeastern Oman: Preliminary report". Rivista italiana di Paleontologia e Stratigrafia. 104 (3): 329–340. doi:10.13130/2039-4942/5337.
  5. ^ a b c Nicora, Alda; Vaslet, Denis; Le Nindre, Yves-Michel (2006-07-01). "First record of Permian conodont "jinogondolella" cf. altaduensis from the Midhnab Member, Khuff Formation, Saudi Arabia". GeoArabia. 11 (3): 91–96. doi:10.2113/geoarabia110391. ISSN 1025-6059.
  6. ^ a b c d e f g h Angiolini, Lucia; Vaslet, Denis; Le Nindre, Yves-Michel; Zarbo, Miriam (2006-10-01). "New records and new taxa of Permian brachiopods from the Khuff Formation, Midhnab Member, central Saudi Arabia". GeoArabia. 11 (4): 45–58. doi:10.2113/geoarabia110445. hdl:2434/30360. ISSN 1025-6059.
  7. ^ a b c d e f Chirat, Régis; Vaslet, Denis; Le Nindre, Yves-Michel (2006-01-01). "Nautiloids of the Permian-Triassic Khuff Formation, central Saudi Arabia". GeoArabia. 11 (1): 81–92. doi:10.2113/geoarabia110181. ISSN 1025-6059.