Earth:Bahariya Formation

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Bahariya Formation
Stratigraphic range: Early Cenomanian[1]
~100–95 Ma
Bahariya Formation McAfee.jpg
Restoration of the environment and animals of the formation
TypeGeological formation
UnderliesEl Heiz Fm., El Naqb Fm.[2]
OverliesBasement[2]
Thickness≈100 m (330 ft)[2]
Lithology
PrimarySandstone
OtherMudstone, siltstone
Location
Coordinates [ ⚑ ] 28°24′20″N 28°48′20″E / 28.40556°N 28.80556°E / 28.40556; 28.80556
RegionWestern Desert
Country Egypt
Type section
Named forBahariya Oasis
Named bySaid
Year defined1962
Bahariya Formation is located in Egypt
Bahariya Formation
Bahariya Formation (Egypt)

The Bahariya Formation (also transcribed as Baharija Formation) is a fossiliferous geologic formation dating back to the early Cenomanian, which outcrops within the Bahariya depression in Egypt, and is known from oil exploration drilling across much of the Western Desert where it forms an important oil reservoir.[1][3][4]

Extent

Restoration of swimming animals of the formation

The Bahariya Formation forms the base of the depression, the lower part of the enclosing escarpment and all of the small hills within.[5] The type section for the formation is found at Gebel El-Dist, a hill at the northern end of the Bahariya depression.[6]

Stratigraphy and sedimentology

Four depositional sequences have been recognised in the Bahariya Formation in the Bahariya depression, separated by three sub-aerial unconformities. The formation was deposited during a period of relative rise in sea level, with each unconformity representing a relative fall in sea level.[1] Each of the individual sequences contains sediments deposited under fluvial, shoreline and shallow marine conditions.

Flora

Thirty different genera are known from Bahariya, including megaflora. Much of the material is yet to be described.[7]

Vascular Plants
Genus Species Abundance Notes Images
Weichselia W. reticulata Dominant plant. Xerophytic tree fern suggestive of a dry tropical climate. File:Cladophlebis retallackii.tif
Agathis / Wollemia An Araucarian conifer, now restricted to Australasia.
Cladophlebis A water fern.
Liriodendrites
Marsilea Water fern.
Nelumbites

Other taxa include Sapindales, Piperaceae, Lauraceae, Platanaceae, Magnoliopsida, Nymphaeaceae, Cornaceae, Proteaceae and Vitaceae not identified at genus level; and miospore and pollen species.

Microfauna and Meiofauna

Foraminifera

Foraminifera of the Bahariya Formation
Genus Species
Charentia C. cuvillieri
Favusella F. washitensis
Mayncina M. orbignyi
Rotalipora R. cushmani
R. reicheli
Thomasinella T. aegyptia
T. fragmentaria
T. punica
Whiteinella W. archaeocretacea

Other microorganisms

Other microorganisms of the Bahariya Formation
Genus Species Images
Botryococcus
Botryococcus
thumb|center|150px|Pediastrum
thumb|center|150px|
Scenedesmus
Coronifera C. oceanica
Cyclonephelium C. edwardsii
C. vannophorum
Dynopterigium D. cladoides
Exochosphaeridium
Florentinia F. cooksoniae
F. mantlii
Kallosphaeridium
Mudrongia M. simplex
Palaeoperidinium P. cretaceum
Pediastrum
Pseudoceratium P. anaphrisum
P. securigerum
Scenedesmus
Spiniferites
Subtilisphaera S. perlucida
S. senegalensis
Xiphophoridium X. alatum

Invertebrates

Molluscs

Molluscs of the Bahariya Formation
Genus Species Notes Images
Baculites A heteromorph ammonite with a nearly straight shell.
Baculites.
Cardium A cockle.
Exogyra A reef-forming true oyster associated with solid substrates and warm temperatures.
Gastrochaena A saltwater clam.
Neolobites N. vibrayeanus A typical rolled ammonite.
Nucula A small saltwater clam.
Ostrea O. flabeata An edible oyster.

Crustaceans (Ostracoda)

Crustaceans of the Bahariya Formation
Genus Species Notes Images
Amphicytherura A. sexta
Anticythereis A. gaensis
Bairdia B. bassiounii
B. elongata
Brachycythere B. ledaforma porosa
Bythoceratina B. avnonensis
B. tamarae
Bythocypris B. eskeri
Cythereis C. algeriana
C. bicornis levis
C. canteriolata
Cytherella C. ovata
C. paenovata
C. parallela
C. sulcata
Fabanella
Looneyella L. sohni
Loxoconcha L. clinocosta
L. fletcheri
Metacytheropteron M. berbericum
Ovocytheridea O. caudata
O. producta
O. reniformis
Paracypris P. acutocaudata
P. angusta
P. mdaouerensis
P. triangularis
Pterygocythere P. raabi
Veeniacythereis V. jezzineensis
Xestoleberis X. obesa

Insects

Direct fossils are sparse, though plant leaves with extensive damage from folivorous insects have been documented.

Vertebrates

Cartilaginous fish

Chondrichthyes of the Bahariya Formation
Genus Species Abundance Notes Images
Aegyptobatus A. kuehnei A sclerorhynchiform.
Modern Gymnura.

thumb|center|150px|Onchopristis tooth.
thumb|center|150px|Modern
Rhinoptera.
Scapanorhynchus

Squalicorax
Modern Squatina.
Asteracanthus A. aegyptiacus A hybodont shark.
Baharipristis B. bastetiae A sclerorhynchiform.
Cretodus C. longiplicatus A shark.
Cretolamna C. appendiculata A mackerel shark.
Distobatus D. nutiae A sclerorhynchiform.
Gymnura G. laterialata A butterfly ray.
Haimirichia H. amonensis A shark previously classified in the genera Odontaspis, Serratolamna, and Carcharias.
Isidobatus I. tricarinatus A sclerorhynchiform.
Marckgrafia M. lybica A sclerorhynchiform.
Onchopristis O. numida One complete cranium and associated vertebrae. A sclerorhynchid rajoid.
Peyeria P. libyca A sclerorhynchiform.
Ptychotrygon P. henkeli A sclerorhynchiform.
Renpetia R. labiicarinata A sclerorhynchiform.
Rhinoptera A batoid ray.
Schizorhiza S. stromeri An unusual sclerorhynchid sawfish that retained its rostral teeth after they were replaced.
Squalicorax S. baharijensis A large shark.
Scapanorhynchus S. subulatus A mitsukurinid similar to the modern goblin shark.
Squatina An angelshark.
Tribodus T. aschersoni A hybodont.

Bony fish

Osteichthyes of the Bahariya Formation
Genus Species Abundance Notes Images
Bawitius B. bartheli A giant bichir.
Ceratodus

thumb|center|150px|Enchodus
thumb|center|150px|
Lepidotes
thumb|center|150px|Mawsonia
thumb|center|150px|
Neoceratodus
thumb|center|150px|Saurodon
Concavotectum C. moroccensis Possibly synonymous with Paranogmius doederleini.
Ceratodus A lungfish.
Coelodus A pycnodontid.
Enchodus One tooth. A predatory fish.
Lepidotes Isolated scales. Possibly misidentified from Bawitius bartheli.
Mawsonia M. lybica Considered a "signature taxon" of the formation. A giant freshwater coelacanth. Species assignation deemed provisional due to the lack of neotype.
Neoceratodus N. africanus A lungfish related to the living Australia n species.
Palaeonotopterus P. greenwoodi Nomen conservandum of the two Plethodus species previously described.
Paranogmius Paranogmius doederleini One vertebra. Holotype lost in World War II. Could be synonymous with Concavotectum moroccensis.
Plethodus P. libycus
P. tibniensis
Holotypes destroyed in World War II, but now believed to have been misidentified Palaeonotopterus greenwoodi.
Retodus R. tuberculatus A lungfish species identified from remains previously assigned to Neoceratodus.
Saurodon Identified by Stromer in 1936, but now rejected due to this genus appearing only in post-Cenomanian Europe and North America. Now listed as Ichthyodectidae incertae sedis.
Stromerichthys S. aethiopicus A predatory bowfin relative.

Testudines

Testudines of the Bahariya Formation
Genus Species Abundance Notes Images
Apertotemporalis A. baharijensis A small pleurodiran turtle, likely belonging to Bothremydidae. Other unnamed species are also present.

Squamates

Squamates of the Bahariya Formation
Genus Species Abundance Notes Images
Simoliophis Abundant First known sea snake, with functional hind legs. Now believed to include elements from different species and at least one of a different, unnamed genus.

Plesiosaurs

Plesiosaurs of the Bahariya Formation
Genus Species Abundance Notes Images
Leptocleidus L. capensis A small plesiosaur that visited brackish or fresh water systems. Though known from both South Africa and England , the Egyptian material lacks diagnostic traits of the genus and is now referred as Polycotylidae incertae sedis.
Leptocleidus

Crocodyliformes

Crocodyliformes of the Bahariya Formation
Genus Species Abundance Notes Images
Aegyptosuchus A. peyeri A poorly known, possibly stomatosuchid crocodile.
Hamadasuchus

thumb|center|150px|Stomatosuchus
Hamadasuchus H. rebouli A terrestrial, dog-like peirosaurid. It is possible that some material previously attributed to Libycosuchus actually belongs to this species.
Libycosuchus L. brevirostris A terrestrial crocodile of uncertain affinities, possibly related to Notosuchus.
Stomatosuchus S. inermis A complete cranium A large, flat-headed stomatosuchid with multiple small conical teeth, and possibly a pelican-like throat pouch. The only remains were destroyed in World War II.
Stromerosuchus S. aegyptiacus Fragmentary remains Nomen dubium assigned to material found in 1911, that were badly damaged in 1922 while being shipped to Germany for study. Some material may belong to Aegyptosuchus and other to Stomatosuchus.

Pterosaurs

Pterosaurs of the Bahariya Formation
Genus Species Material Notes Images
Pterosauria indet.[8] Indeterminate Left first wing phalanx A medium-sized pterosaur. The first record of a pterosaur from Egypt.

Sauropods

Sauropods of the Bahariya Formation
Genus Species Material Notes Images
Aegyptosaurus[3] A. baharijensis[3] Partial postcranial skeleton[9] A titanosaur of about 15 meters. All remains were destroyed in World War II.
Aegyptosaurus

Dicraeosaurus


Paralititan
Dicraeosaurus D. hansemanni Isolated scapula and vertebra Identified by Stromer in 1932. Subsequently considered a rebbachisaurid, or a third, unnamed titanosaur.
Paralititan[3] P. stromeri[3] Partial postcranial skeleton[10] One of the largest titanosaurs of the Cretaceous, with a 1.69 meters long humerus and an estimated total length of 26 meters.

Theropods

Theropods of the Bahariya Formation
Genus Species Abundance Notes Images
Abelisauridae indet.[11] Indeterminate "MUVP 477, an isolated caudal (tenth) cervical vertebra" A medium-sized abelisaurid, estimated around 5.77 meters (~18.9 feet) long. The first unambiguous abelisaurid known from the Bahariya Formation.
Abelisauridae indet.

Bahariasaurus

Carcharodontosaurus

Spinosaurus
Bahariasaurus B. ingens[3] A medium-sized theropod of uncertain affinities. Possibly a megaraptoran, a relative of Deltadromeus, or both.
Carcharodontosaurus[3] C. saharicus[3] A large carcharodontosaurid allosauroid.
Elaphrosaurus E. bambergi Material now considered to be indeterminate theropod remains.[3]
Sigilmassasaurus[3] S. brevicollis Previously considered a species of Spinosaurus, or a synonym of S. aegyptiacus.
Spinosaurus S. aegyptiacus Most common dinosaur of the formation. A large spinosaurid.

In addition, there are isolated theropod teeth disputedly assigned to dromaeosaurids, or to abelisaurids.

See also

  • List of dinosaur-bearing rock formations

References

  1. 1.0 1.1 1.2 Catuneanu O., Khalifa M.A. & Wanas H.A. (2006). "Sequence stratigraphy of the Lower Cenomanian Bahariya Formation, Bahariya Oasis, Western Desert, Egypt". Sedimentary Geology 190 (1–4): 121–137. doi:10.1016/j.sedgeo.2006.05.010. http://www.wuestenschiff.de/dateien/bahariya.pdf. 
  2. 2.0 2.1 2.2 Catuneany et al., 2006, p.122
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Weishampel, David B; et al (2004). "Dinosaur distribution (Late Cretaceous, Africa)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 604. ISBN:0-520-24209-2.
  4. Macgregor D.S. & Moody R.T.G. (1998). "Mesozoic and Cenozoic petroleum systems of North Africa". in Macgregor D.S.. Petroleum geology of North Africa. Special Publications. 132. Geological Society. pp. 201–216. ISBN 9781862390041. http://sp.lyellcollection.org/content/132/1/201.abstract. 
  5. Khalifa M.A. & Catuneanu O. (2008). "Sedimentology of the fluvial and fluvio-marine facies of the Bahariya Formation (Early Cenomanian), Bahariya Oasis, Western Desert, Egypt". Journal of African Earth Sciences 51 (2): 89–103. doi:10.1016/j.jafrearsci.2007.12.004. 
  6. Tanner L.H. & Khalifa M.A. (2010). "Origin of ferricretes in fluvial-marine deposits of the Lower Cenomanian Bahariya Formation, Bahariya Oasis, Western Desert, Egypt". Journal of African Earth Sciences 56 (4–5): 179–189. doi:10.1016/j.jafrearsci.2009.07.004. 
  7. Ijouhier, Jamale (2016) A reconstruction of the palaeoecology and environmental dynamics of the Bahariya Formation of Egypt. PeerJ Preprints, https://doi.org/10.7287/peerj.preprints.2470v1
  8. Salem, Belal S.; Sallam, Hesham M.; El-Sayed, Sanaa; Thabet, Wael; Antar, Mohammed; Lamanna, Matthew C. (October 2019). "NEW DINOSAUR, PTEROSAUR, AND CROCODYLIFORM FOSSILS FROM THE UPPER CRETACEOUS (CENOMANIAN) BAHARIYA FORMATION OF THE BAHARIYA OASIS, EGYPT". Society of Vertebrate Paleontology (SVP) – Brisbane, Queensland, Australia. https://www.researchgate.net/publication/344722122. 
  9. "Table 13.1," in Weishampel, et al. (2004). Page 267.
  10. "Table 13.1," in Weishampel, et al. (2004). Page 269.
  11. Salem, Belal S.; Lamanna, Matthew C.; O'Connor, Patrick M.; El-Qot, Gamal M.; Shaker, Fatma; Thabet, Wael A.; El-Sayed, Sanaa; Sallam, Hesham M. (2022). "First definitive record of Abelisauridae (Theropoda: Ceratosauria) from the Cretaceous Bahariya Formation, Bahariya Oasis, Western Desert of Egypt". Royal Society Open Science 9 (6): 220106. doi:10.1098/rsos.220106. PMID 35706658.