Muwaqqar Chalk-Marl Formation | |
---|---|
Stratigraphic range: | |
Type | Geological formation |
Underlies | Um Al'Rijam Chert-Limestone Formation |
Overlies | Alhisa Phosphorite Formation |
Lithology | |
Primary | Chalk, marl |
Other | Oil shales |
Location | |
Coordinates | 31°42′N36°30′E / 31.7°N 36.5°E |
Approximate paleocoordinates | 14°54′N29°48′E / 14.9°N 29.8°E |
Country | Jordan |
Type section | |
Named for | Al-Muwaqqar |
Named by | M. Masri |
Year defined | 1963 |
The Muwaqqar Chalk-Marl Formation or Muwaqqar Formation is a Late Cretaceous (Maastrichtian) and early Paleogene-aged geological formation in Jordan, cropping out across the Jordanian Highlands from north to south. It is the geological formation containing Jordan's famous oil shales, which are among the largest in the world. [2] [3] Some outcrops of the formation contain extremely well-preserved fossils, making it a lagerstätte. [4] [5]
The formation appears to have been deposited in a pelagic subtropical environment on the outer continental shelf of the Afro-Arabian continent, with the Harrana locality being deposited no deeper than 100 metres (330 ft) below the surface, based on the occurrence of depth-limited fauna such as nurse sharks. [4] The formation of this habitat likely originates from a major marine transgression of the Tethys Ocean at the same time as this depositional event, turning it into an open water ecosystem. The oil shales may have formed from cold upwelling currents from the Tethys that increased the region's planktonic productivity, with these fossilized plankton eventually turning into oil. [2] [3] The sites of excellent fossil preservation may have been formed by anoxic conditions on the seafloor hindering the decomposition of organic matter as well as rapid burial of fossils, although the presence of bottom-dwelling scavengers suggests that anoxic conditions must have been relatively moderate. [4]
While the formation as a whole lasts from the early Maastrichtian to the end of the Paleocene based on foraminifera-based dating, a significant uncomformity exists in some localities at the Cretaceous-Paleogene boundary, which may be due to a drop in sea levels at the time, with deposition continuing following a second sea level rise in the Paleocene. [1] In addition, the highly fossiliferous portion of the formation was only deposited in the span of a few hundred thousand years at the end of the Maastrichtian. [6]
A locality in Harrana is a Konservat-Lagerstätte with extremely well-preserved fossils that were deposited during the latest Maastrichtian, around 66.5 to 66.1 million years ago, [6] making it one of the last lagerstatten to be deposited before the Cretaceous-Paleogene extinction event. The preservation is akin to that of the older, more well-known Sannine Formation from Lebanon. Fossils are contained in concretions exposed by limestone mining, which started in the Harrana region around 1995. Notable fossils from this locality include articulated fish and mosasaur skeletons, mosasaur skin impressions, and evidence of mosasaur carcasses scavenged by nurse sharks & other fishes. [4]
The fossil potential of the Harrana locality was documented by geologist Hani Kaddumi, who described most of the formation's taxa in a 2009 book. Many fossils from this locality are held in the Eternal River Museum of Natural History in Jordan. [4]
The following list of biota is based primarily on Kaddumi (2009). Unless stated otherwise, a majority are from the Harrana locality: [4]
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Batoidea indet. | Articulated pectoral wing | A gigantic ray of uncertain affinities. | ||
Cretalamna | C. biauriculata | Teeth | An otodontid shark. | |
Ginglymostoma | G. sp. | Teeth | A nurse shark, teeth found embedded in a fossil mosasaur carcass. | |
Harranahynchus | H. minutadens | 3 articulated specimens, one nearly complete | A sawskate. | |
Lamniformes indet. | Nearly complete specimen | A nearly complete mackerel shark. | ||
Myliobatidae indet. | Complete specimen | A complete, fully-preserved eagle ray. | ||
Schizorhiza | S. stromeri | Nearly complete rostrum | A sawskate. | |
Squalicorax | S. pristodontus | Teeth | A crow shark. |
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
'Beryciformes' indet. | Complete skeletons | A "beryciform" under the sensu lato interpretation, but potentially a veliferid. [7] | ||
Cimolichthys sp. | Articulated skeleton | A cimolichthyid aulopiform. | ||
Dercetidae indet. | Complete skeleton | A dercetid aulopiform, similar to Dercetis triqueter and possibly a new species of Dercetis. | ||
Elopidae indet. | Complete skeleton | A relative of ladyfish. | ||
Enchodus | E. harranaensis | Articulated partial specimens, isolated teeth | An enchodontid aulopiform. | |
Eurypholis | E. sp. | Articulated skeletons | An enchodontid aulopiform. | |
Ichthyodectes | I. sp. | Articulated skull, rest of the skeleton most likely lost | An ichthyodectid ichthyodectiform. | |
Ichthyodectidae indet. | Poorly-preserved articulated skull & vertebral column | An indeterminate ichthyodectid with very large teeth. | ||
Percomorpha indet. | Complete skeleton | A moonyfish-like percomorph (initially identified as a perciform). [7] | ||
Postredectes | P. harranaensis | Articulated skull with associated remains | An ichthyodectid ichthyodectiform. | |
Stratodus | S. apicalis | Four fully articulated skulls | A dercetid aulopiform. | |
Saurocephalus | S. longicorpus | Six articulated specimens, the most complete known for the genus. | A saurodontid ichthyodectiform. | |
Teleostei indet. | Complete skeleton | A bizarre fish with a deeply forked tail and a stooped forehead akin to that of a dolphinfish. Taxonomic identity uncertain. |
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Rarosaurus | R. singularis | Rostrum with teeth | An indeterminate marine reptile, initially described as a late-surviving polycotylid plesiosaur, but more recently found to possibly be a marine crocodylomorph. [8] |
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Carinodens | C. palistinicus | A complete skull, some vertebrae, and digits from front flippers. | A globidensine, the most completely known member of its genus. Likely adapted to a pelagic lifestyle. | |
Harranasaurus | H. khuludae | Right dentary | A small durophagous globidensine. Remains very rare. | |
Mosasauridae indet. | Articulated hind paddle | A mosasaur of uncertain affinities. | ||
Mosasaurus | M. hoffmani | Teeth | A mosasaurine. | |
M. sevciki | Hindlimbs, sacral vertebrae, preserved scales | |||
M. sp. 1 | Front paddle, humerus | |||
M. sp. 2 | Vertebra | |||
Plioplatecarpini indet. | Hind paddle | A plioplatecarpine. | ||
Prognathodon | P. hashimi (= Tenerasaurus ) | Complete post-cranial skeleton missing skull. | A prognathodontine. P. primus has the first known complete mosasaur skull from the Middle East. | |
P. hudae | Left dentary. | |||
P. primus | Complete skull. | |||
P. sp. 1 | Cranium with teeth | |||
P. sp. 2 | Partial dentary with teeth | |||
P. sp. 3 | Cranial elements including left maxilla with teeth. | |||
P. sp. 4 | Lumbar vertebrae and pygal | |||
P. sp. 5 | Two teeth | |||
Tylosaurinae indet. | Front paddle. | A tylosaurine. |
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Cheloniidae indet. | Articulated pectoral girdle. | A very large cheloniid sea turtle. | ||
Chelonioidea indet. 1 | A right humerus | A very large sea turtle. | ||
Chelonioidea indet. 2. | Front paddle | A very large sea turtle. | ||
Gigantatypus | G. salahi | A right humerus. | A very large cheloniid sea turtle. |
Genus | Species | Material | Locality | Notes | Images |
---|---|---|---|---|---|
Inabtanin | I. alarabia | Jaws, vertebrae, and front limb bones. | Tal Inab 6 | An azhdarchoid pterosaur, one of the most complete from the region. [5] | |
Nyctosauridae indet. | Wing bones. | Harrana | A nyctosaurid pterosaur. |
Based on Krewesh et al (2014) and Jagt et al (2017): [2] [6]
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Baculites | B. ovatus | Jebal Khuzaym, Harrana | A baculitid ammonite. | |
Libycoceras | L. acutidorsatus | Harrana | A sphenodiscid ammonite. | |
L. cf. ismaeli | Jebal Khuzaym | |||
Menuites | M.fresvillensis | Harrana | A pachydiscid ammonite. | |
Pachydiscus | P. dossantosi | Harrana | A pachydiscid ammonite. | |
Sphenodiscus | S. lobatus | Jebal Khuzaym | A sphenodiscid ammonite. |
Genus | Species | Material | Notes | Images |
---|---|---|---|---|
Lyropecten | L. mayereymari | A scallop. [9] | ||
Tenuipteria | T. argentea | An inoceramid. |
The Maastrichtian is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from 72.1 to 66 million years ago. The Maastrichtian was preceded by the Campanian and succeeded by the Danian.
The Mosasaurinae are a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "mosasaurines" and their fossils have been recovered from every continent except for South America.
Globidens is an extinct genus of mosasaurid oceanic lizard classified as part of the Globidensini tribe in the Mosasaurinae subfamily. Globidens belongs to the family Mosasauridae, which consists of several genera of predatory marine lizards of various sizes that were prevalent during the Late Cretaceous. Specimens of Globidens have been discovered in Angola, Brazil, Morocco, Syria and the United States. Among mosasaurs, Globidens is probably most well known for the highly rounded, globe-like teeth that give it its name.
Prognathodon is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Mosasaurinae subfamily, alongside genera like Mosasaurus and Clidastes. Prognathodon has been recovered from deposits ranging in age from the Campanian to the Maastrichtian in the Middle East, Europe, New Zealand, and North America.
Carinodens is an extinct genus of Cretaceous marine lizard belonging to the mosasaur family. "Carinodens" means "keel teeth" and was named in 1969 as a replacement name for Compressidens, "compressed teeth", which was already in use for a gadilidan scaphopod mollusk.
Ichthyodectiformes is an extinct order of marine stem-teleost ray-finned fish. The order is named after the genus Ichthyodectes, established by Edward Drinker Cope in 1870. Ichthyodectiforms are usually considered to be some of the closest relatives of the teleost crown group.
Stratodus is a genus of giant prehistoric aulopiform fish found in Cretaceous-aged marine strata of Kansas, Alabama, Morocco, Israel, and Niger, South Dakota, Jordan. It has also been found in the Tamaguélelt Formation of Mali, dating to the Lower Eocene, indicating that Stratodus survived the Cretaceous-Paleogene extinction event. This sleek fish has an upper jaw filled with multiple rows of tiny teeth and was the largest aulopiform, reaching 5 meters in length.
The Maastricht Formation, named after the city of Maastricht in the Netherlands, is a geological formation in the Netherlands and Belgium whose strata date back to the Late Cretaceous, within 500,000 years of the Cretaceous–Paleogene boundary, now dated at 66 million years ago. The formation is part of the Chalk Group and is between 30 and 90 metres thick. It crops out in southern parts of Dutch and Belgian Limburg and adjacent areas in Germany. It can be found in the subsurface of northern Belgium and southeastern Netherlands, especially in the Campine Basin and Roer Valley Graben. Dinosaur remains are among the fossils that have been recovered from the formation.
Saurocephalus is an extinct genus of ray-finned fishes within the family Saurodontidae. The genus was first described in 1824 and contains six or seven species, including the type species S. lanciformis. Saurocephalus first appeared during the early Valanginian and continued on to the Maastrichtian, where it nearly went extinct. However, the recent discovery of S. lanciformis remains from the earliest Paleocene indicates that it just barely survived into the Cenozoic. This would make it the last surviving ichthyodectiform.
Wadi Harrana is a seasonal stream (wadi) in the eastern Jordanian Badia, about sixty kilometers southeast of the city of Amman. It runs eastwards from the edge of the Jordanian Highlands to the Azraq oasis.
Gigantatypus is an extinct late Maastrichtian sea turtle that lived in the southern regions of the Tethys Ocean about 100–120 kilometres (62–75 mi) off the north eastern margins of Cretaceous Africa immediately before the Cretaceous–Paleogene extinction events . Fossil remains of Gigantatypus are so far only represented in sediments from the Muwaqqar Chalk-Marl Formation of Jordan. Estimated at over 3.5 metres (11 ft) in length, members of this genus reached remarkably large proportions equivalent to that of or possibly even exceeding Archelon Wieland, 1896, considered as the largest marine turtles to ever roam the oceans of the world. Although Gigantatypus apparently did not survive the K/T boundary, which also was the fate of other gigantic marine turtles such as protostegids, other genera of Cheloniidae, though significantly smaller in size survived the mass extinction and continued on until the present day.
Harranahynchus is an extinct genus of schizorhizid sawskate that lived during the Late Cretaceous. It contains one valid species, Harranahynchus minutadens. It is known from relatively complete cranial and body fossils found in the Muwaqqar Chalk Marl Formation of Jordan, dating back to the late Maastrichtian. Its rostral denticles are extremely small and are arranged in batteries like its close relative Schizorhiza. It has an estimated length of around 2 m (6.6 ft).
Nyctosauridae is a family of specialized soaring pterosaurs of the late Cretaceous Period of North America, Africa, and possibly other continents including South America. It was named in 1889 by Henry Alleyne Nicholson and Richard Lydekker.
The Globidensini or Globidentatini are a tribe of mosasaurine mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the tribe, known as "globidensins" or "globidensine mosasaurs", have been recovered from North America, Europe, Africa and Asia. The tribe contains the genera Globidens, Carinodens, Igdamanosaurus, Harranasaurus and Xenodens. Features of the maxilla and digits make the placement of Carinodens and Xenodens in the tribe uncertain; some researchers have suggested that they may be more appropriately placed in the Mosasaurini.
Harranasaurus is an extinct genus of globidensin mosasaur from Jordan. The genus contains one known species, H. khuludae from the Muwaqqar Chalk Marl Formation of Jordan.
Thalassotitan is an extinct genus of large mosasaurs that lived during the late Maastrichtian of the Cretaceous period in what is now Morocco, around 66 million years ago. The only known species is T. atrox, described in 2022 from fossils discovered in the Ouled Abdoun Basin, where many other mosasaurs have been found. It was assigned to the tribe Prognathodontini alongside other mosasaurs like Prognathodon and Gnathomortis. The prognathodontines are separated from other mosasaurs based on their massive jaws and robust teeth.
Rarosaurus is an extinct genus of marine reptile that lived during the Late Cretaceous. It contains one valid species, R. singularis, and it was found in the Muwaqqar Chalk Marl Formation of Jordan.
Inabtanin is an extinct genus of azhdarchoid pterosaurs from the Late Cretaceous Muwaqqar Formation of Jordan. The genus contains a single species, I. alarabia, known from a partial skeleton. Inabtanin represents one of the most complete pterosaur taxa known from the Afro-Arabia region.