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]
| Bahariya Formation | |
|---|---|
| Stratigraphic range: Early Cenomanian[1] ~ | |
 Restoration of the environment and animals of the formation | |
| Type | Geological formation |
| Underlies | El Heiz Fm., El Naqb Fm.[2] |
| Overlies | Basement[2] |
| Thickness | ≈100 m (330 ft)[2] |
| Lithology | |
| Primary | Sandstone |
| Other | Mudstone, siltstone |
| Location | |
| Coordinates | 28°24′20″N 28°48′20″E / 28.40556°N 28.80556°E |
| Region | Western Desert |
| Country |  Egypt |
| Type section | |
| Named for | Bahariya Oasis |
| Named by | Said |
| Year defined | 1962 |
  Bahariya Formation (Egypt) | |
Extent
edit
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
editFour 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.
Microfauna and Meiofauna
editForaminifera
edit| 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
edit| Other microorganisms of the Bahariya Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Images | ||||
| Botryococcus |    | |||||
| 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
editMolluscs
edit| Molluscs of the Bahariya Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Notes | Images | |||
| Baculites | A heteromorph ammonite with a nearly straight shell. |  | ||||
| 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)
edit| 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
editDirect fossils are sparse, though plant leaves with extensive damage from folivorous insects have been documented.
Vertebrates
editCartilaginous fish
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Chondrichthyes of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Abundance | Notes | Images |
| Aegyptobatus | A. kuehnei | A sclerorhynchiform. |       | |
| 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
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Osteichthyes of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Abundance | Notes | Images |
| Bawitius | B. bartheli | A giant bichir. |       | |
| 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 Australian species. | ||
| Obaichthys | O. africanus | An obaichthyid lepisosteiform. Remains formerly attributed to "Stromerichthys".[7] | ||
| 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 fish initially identified as a bowfin relative, but now thought to be a chimera consisting of remains assignable to Bawitius, Obaichthys, and others.[8] | ||
Testudines
edit| 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
edit| 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
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| 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. |  | |
Crocodyliformes
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Crocodyliformes of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Abundance | Notes | Images |
| Aegyptosuchus | A. peyeri | A poorly known, possibly stomatosuchid crocodile. | .jpg)  | |
| 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
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Pterosaurs of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Material | Notes | Images |
| Pterosauria indet.[9] | Indeterminate | Left first wing phalanx | A medium-sized pterosaur. The first record of a pterosaur from Egypt. | |
Dinosaurs
editSauropods
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Sauropods of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Material | Notes | Images |
| Aegyptosaurus[3] | A. baharijensis[3] | Partial postcranial skeleton[10] | A titanosaur of about 15 meters. All remains were destroyed in World War II. |  
 |
| 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[11] | One of the largest titanosaurs of the Cretaceous, with a 1.69 meters long humerus and an estimated total length of 26 meters. | |
Theropods
editColor key
|
Notes Uncertain or tentative taxa are in small text; |
| Theropods of the Bahariya Formation | ||||
|---|---|---|---|---|
| Genus | Species | Abundance | Notes | Images |
| Abelisauridae indet.[12] | 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. |     |
| Bahariasaurus | B. ingens[3] | A medium-sized theropod of uncertain affinities. Possibly a megaraptoran, a relative of Deltadromeus, or both. | ||
| Bahariasaurid? | Deltadromeus agilis? | |||
| Ceratosauria? | ||||
| Carcharodontosaurus[3] | C. saharicus[3] | A large carcharodontosaurid allosauroid. | ||
| Elaphrosaurus | E. bambergi or aff | Material now considered to be indeterminate theropod remains.[3] | ||
| Erectopus? | Erectopus sauvagei? | |||
| 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.
Flora
editThirty different genera are known from Bahariya, including megaflora. Much of the material is yet to be described.[13][14] Other taxa include Sapindales, Piperaceae, Lauraceae, Platanaceae, Magnoliopsida, Nymphaeaceae, Cornaceae, Proteaceae and Vitaceae not identified at genus level; and miospore and pollen species.[15][16]
| Vascular Plants | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Abundance | Notes | Images | ||
| Agathis / Wollemia[17] | A/W spp. | Few Specimens | An Araucarian conifer, now restricted to Australasia. |
   | ||
| Araliaephyllum?[13][15] | Indeterminate ("Morphotype-14") | Few Specimens | Suggested to be related with Lauraceae | |||
| Cladophlebis[13][15] | C. spp. | Few Specimens | Fern Laflets | |||
| Cornophyllum[13][15] | C. distense | Few Specimens | Suggested to be related with Cornaceae | |||
| Cinnamophyllum?[13][15] | Indeterminate ("Morphotype-12") | Few Specimens | Suggested to be related with Lauraceae | |||
| Eucalyptolaurus/"Myrtophyllum”(?)[15][16] | Indeterminate ("Morphotype-08") | Few Specimens | Specimens of the family Lauraceae | |||
| Laurophyllum[13][15] | L. africanum | Few Specimens | Specimens of the family Lauraceae | |||
| Liriophyllum[13][15] | L. farafraense | Few Specimens | Specimens of the family Magnoliaceae | |||
| Marsilea[17] | aff. Marsilea spp. | Few Specimens | Water fern. | |||
| Magnoliid[15][16] |
|
Few Specimens | Shows festooned brochidodromous venation | |||
| Magnoliaephyllum[15] |
|
Few Specimens | Possible affinities with Lauraceae | |||
| Nelumbites[15][16] |
|
Common occurrence in the lower shale bed | Typical leaves of the faimily Nelumbonaceae | |||
| Paradoxopteris[13][15] | P. stromeri | Co-Dominant plant | Xerophytic tree fern suggestive of a dry tropical climate. | |||
| Plumafolium?[15][16] | Indeterminate ("Morphotype-18") | Few Specimens | A Monocot, probably related with Liliopsida | |||
| Rogersia[13][15] | R. longifolia | Few Specimens | Likely lobes of a much bigger leaf of Sapindopsis type | |||
| Typhaephyllum[13][15] | cf. T. sp. | Few Specimens | Interpreted as a monocot, probably related to Typhaceae | |||
| Vitiphyllum[13][15] | V. aff. multifidum | Few Specimens | Some similarities with Pabiania of the family Lauraceae | |||
| Weichselia[13] | W. reticulata | Dominant plant | Xerophytic tree fern suggestive of a dry tropical climate. | |||
See also
editReferences
edit- ^ a b c Catuneanu O., Khalifa M.A. & Wanas H.A. (2006). "Sequence stratigraphy of the Lower Cenomanian Bahariya Formation, Bahariya Oasis, Western Desert, Egypt" (PDF). Sedimentary Geology. 190 (1–4): 121–137. Bibcode:2006SedG..190..121C. doi:10.1016/j.sedgeo.2006.05.010.
- ^ a b c Catuneany et al., 2006, p.122
- ^ a b c d e f g h i j 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.
- ^ Macgregor D.S. & Moody R.T.G. (1998). "Mesozoic and Cenozoic petroleum systems of North Africa". In Macgregor D.S.; Moody R.T.G.; Clark-Lowes D.D. (eds.). Petroleum geology of North Africa. Special Publications. Vol. 132. Geological Society. pp. 201–216. ISBN 9781862390041.
- ^ 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. Bibcode:2008JAfES..51...89K. doi:10.1016/j.jafrearsci.2007.12.004.
- ^ 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. Bibcode:2010JAfES..56..179T. doi:10.1016/j.jafrearsci.2009.07.004.
- ^ Pimentel, Ricardo; Barroso-Barcenilla, Fernando; Berrocal-Casero, Mélani; Callapez, Pedro Miguel; Ozkaya de Juanas, Senay; dos Santos, Vanda F. (2023). "On the Occurrence of the Gar Obaichthys africanus Grande in the Cretaceous of Portugal: Palaeoecological and Palaeobiogeographical Implications". Geosciences. 13 (12): 372. Bibcode:2023Geosc..13..372P. doi:10.3390/geosciences13120372. ISSN 2076-3263.
- ^ Cavin, Lionel; Boudad, Larbi; Tong, Haiyan; Läng, Emilie; Tabouelle, Jérôme; Vullo, Romain (2015). "Taxonomic composition and trophic structure of the continental bony fish assemblage from the early late cretaceous of Southeastern Morocco". PLOS ONE. 10 (5): e0125786. Bibcode:2015PLoSO..1025786C. doi:10.1371/journal.pone.0125786. ISSN 1932-6203. PMC 4446216. PMID 26018561.
- ^ 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.
- ^ "Table 13.1," in Weishampel, et al. (2004). Page 267.
- ^ "Table 13.1," in Weishampel, et al. (2004). Page 269.
- ^ 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. Bibcode:2022RSOS....920106S. doi:10.1098/rsos.220106. PMC 9174736. PMID 35706658.
- ^ a b c d e f g h i j k l Lejal-Nicol, A; Dominik, W. (1990). "Sur la paleoflore a Weichseliaceae et a angiospermes du Cenomanien de la region de Bahariya (Egypte du Sud-Ouest)". Berliner geowissenschaftliche Abhandlungen A. 120 (5): 957–991.
- ^ 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
- ^ a b c d e f g h i j k l m n o p El Atfy, Haytham; Coiffard, Clément; El Beialy, Salah Y.; Uhl, Dieter (2023-01-30). "Vegetation and climate change at the southern margin of the Neo-Tethys during the Cenomanian (Late Cretaceous): Evidence from Egypt". PLOS ONE. 18 (1): e0281008. Bibcode:2023PLoSO..1881008E. doi:10.1371/journal.pone.0281008. ISSN 1932-6203. PMC 9886267. PMID 36716334.
- ^ a b c d e El Atfy, Haytham; Coiffard, Clément; Uhl, Dieter; Spiekermann, Rafael; El Khoriby, Essam M.; Aleraky, Heba; Mohamed, Ahmed (2023). "A new florula dominated by angiosperms from the Cenomanian of Egypt". Cretaceous Research. 149: 105554. Bibcode:2023CrRes.14905554E. doi:10.1016/j.cretres.2023.105554. ISSN 0195-6671.
- ^ a b Lyon, M. A.; Johnson, K. R.; Wing, S. L.; Nichols, D. J.; Lacovara, K. J.; Smith, J. B. (2001). "Late Cretaceous equatorial coastal vegetation: new megaflora associated with dinosaur finds in the Bahariya Oasis, Egypt". Geological Society of America, Annual Meeting: 198.