Английская Википедия:Aganane Formation

Материал из Онлайн справочника
Перейти к навигацииПерейти к поиску

Шаблон:Short description Шаблон:Infobox rockunit

The Aganane Formation is a Pliensbachian (Early Jurassic) geologic formation in the Azilal, Béni-Mellal, Ouarzazate, Tinerhir and Errachidia provinces, central Morocco, being the remnant of a local massive Carbonate platform, and known mostly for its rich tracksites (up to 1350 tracks in 1988) including footprints of thyreophoran, sauropod and theropod dinosaurs.[1] This formation has been dated to the Pliensbachian stage of the Lower Jurassic, thanks to the find of the ammonite Arieticeras cf. algovianum, indicator of Middle Domerian (=Uppermost Pliensbachian) in the upper zone, and lower delimitation by the foraminifers Mayncina termieri and Orbitopsella praecursor (indicators of Carixian=Lower Pliensbachian age).[2] The dinosaur tracksites are all located a few metres below the Pliensbachian-Toarcian limit, being coeval and connected with the lowermost layers of the continental Azilal Formation. The Aganane Formation was also coeval with the Jbel Taguendouft Formation and the Tamadout 1 Formation, all developed along a local "platform-furrow" in the Middle Atlas Mountains, that act as a barrier controlling the western border of the Jurassic Atlas Gulf.[3] The nearshore sections, including both carbonate platforms and close to sea terrestrial facies where located on an isolated internal domain thanks to the control of the barrier, allowing the Aganane Formation to develop on a hot and humid climate, where a local algal marsh had intermittent progradations, intercalated with a layer of terrigenous continental origin.[3] The ichnosites were developed in tidal flats and coastal deposits suitable to sea flooding.[4]

The Aganane Formation is a member of the Pliensbachian facies section of the Central Atlas, which are distributed from west to east: The Aït Chitachen Formation at Demnate (continental-fluvial, coastal lagoon), the Aganane itself at Azilal.[4] At Tazoult, part of the Azilal profile contacts the bottom with the karst Talmest-Tazoult Formation, then a section where the Aganane itself indicates an eastward expansion of the carbonate facies, finally, the most recent Pliensbachian strata belong to the Amezraï Formation (Intertidal to coastal marine), this last change being the result of a transgression where we see a westward advance of the Imilchil pelagic facies.[4]

At Tazoult, the presence of a Diapir (the Tazoult salt wall) is remarkable. In the Pliensbachian, this area begins with the deposition of the Talmest-Tazoult Formation, and then is invaded from the west by the shallow marine carbonate platform of the Aganane Formation.[5] At this time, a decrease in the growth rate of the diapir is detected compared to the Sinemurian. In fact, with the eastward extension of the Aganane Formation, the Tazoult salt wall registers a major change towards shallower facies, confirming a higher diapir relief and a decrease in water depth towards this area during the Pliensbachian, not excluding a complete stop of diapir activity in this interval.[5]

Paleoenvironment

Шаблон:Multiple image

The Aganane Formation is characterized as representing a carbonate platform, the most important Lower Jurassic platform in the central High Atlas, bounded to the west at Demnat by the Aït Chitachen Formation, which represents environments ranging from fluvial to coastal lagoons, with palynological residues Corollina quezelii & Corollina yvesi (Cheirolepidiaceae) as dominant, indicating an arid environment, accompanied by Cupressacites oxycedroides & Diadocupressacites moghrebiensis, both palynological residues of Cupressaceae.[6]

The Carbonates of this unit were subjected to an examination of the diagenetic characteristics of the carbonates, allowing the construction of a model of diagenetic environments, where changes in the surface environment were consistently reflected in a sequence of rocks by diagenetic characteristics, maybe a tentative correlation of major events, such as Hurricanes.[7] The carbonate rocks that form the massive "Aganane Platform" are clearly influenced by tidal and shallow marine flows, ascribed to three environments: supratidal, intertidal and subtidal.[8] The supratidal sector is diverse, including continental deposits with abundant quartz-rich cricundant deposits and fluvial channels, as well as others composed of considerable thicknesses of stratified gypsum and chicken-wire cargneules, lime and dolomite shales and marls, with drying cracks, caliche crusts and vadose pisoliths. These sediments suggest a continental zone bordering river courses, connected to coastal sectors where shales and siltstones derived from Sabkhas in which interstitial evaporites were formed.[9][10] Intertidal deposits are composed of algal laminates, bioturbated pelletiferous shales, uniformitarian shales and wackestones with disruptive channels and storm sequences. Algal laminated Boundstones developed in both supratidal and intertidal zones, following present-day patterns such as Shark Bay in Australia or the Persian Gulf. Whereas the pelletoid lime packstone/wackestone facies most likely represented tidal flat areas, or analogs to modern coastal mangrove growth.[9][10] Subtidal deposits include both those of an intertidal nature, indicating shallow water or coastal lagoons, with extensive accumulations of skeletal lime packstones, oolitic tidal deltas and offshore bars, oncoliths and coral reefs, and occasional Opisoma spp. While further east the more open subtidal conditions are represented by flint-bearing calcareous shales and sparse faunas where ammonites begin to appear.[9][10]

Файл:Poisson dans le désert (lagune imlili dakhla).jpg
Modern Sebkha of Imlily, near Dakhla. Certain sections of the Aganane Formation present beds resembling this type of ecosystem

The Carbonate Facies of the High Atlas "Middle Lias" (Pliensbachian) generally have a low bathymetry. They show a notable evolution from east to west from a lagoon-marine facies to brackish facies. At the level of the Azilal Atlas, the Middle Lias occurs on both sides of the Demnat Fault: to the southwest of the fault, the Aït Bazzi Formation with dolomitic and red marly facies (lagoonal and lagoon-evaporitic facies), while to the northeast develop the thicker facies of the Aganane Formation.[11] In this area, formations of this stage begin either with conglomeratic facies associated with red marls or with scree and conglomerates associated with local erosion, recovering the same lower Pliensbachian emersion phase observed in the Beni-Mellal Atlas.[11] Toward the south, the "basin" facies ends at the bottom of the gulf near the Jbel Oukarde accident, at the western end of the Tilougguit syncline. The southern limit of this basin, hidden by the later sediments, corresponds to the present-day course of the Azilal-Anergui submeridian fault. Toward the south, on the Amezraï and Aït Bouguemmez basins, a platform zone was established in the heart of the Central High Atlas, consisting of the Jbel Choucht, Aganane, Assemsouk, and Amezraï formations.[11] The Jbel Choucht Formation is the type locality here, characterized by a great development of coralligenous facies. The Jbel Choucht Formation is also present towards the north-central High Atlas, but without any reef character, being rather rich in megalodont bivalves, while the Aganane Formation presents more or less the same characteristics as those described in the Beni-Mellal Platform. To the east, at the level of the Jbel Aroudane, the thickening and sedimentary polarity of the Jbel Choucht Formation occurs this time southward, with a W-E subsident basin centered on the Jbel Azourki and the Jbel Aroudane.[11]

In the Aganane Formation towards terminal Carixian (Lias biozone C2 in the High Atlas of Morocco) several sedimentary environments are distinguished in the carbonate inner platform. These environments are characterized by rhythmic sedimentation composed of metric sedimentary sequences analogous to present-day "marnières".[12] Lithologically, there are two juxtaposed sedimentary units that represent two types of complex environments: a first assemblage that includes the marlodolomitic unit of the Aganane Formation and the Aït Bazzi Formation; these units are also equivalent to lagoonal and lagoon-evaporitic facies.[12] This sedimentary assemblage corresponds to a carbonate supratidal coastal plain environment regularly overlain by red marl deposits of continental origin, which can be compared to the modern Sabkhas in the Persian Gulf, but in a less arid climatic context, for the frequent presence of dinosaur tracks suggests extensive vegetation cover in the hinterland, and thus high annual precipitation, suggesting overall tropical conditions reminiscent of the Andros Island model in the Bahamas.[12] A second set (a light gray limestone-dolomite subunit) more distal to the inner platform, in which the environment varies, repeatedly, from subtidal to supratidal conditions, from marine to coastal plain deposits, sometimes showing red terrigenous intercalations, revealing the presence of local cycles evolving from temporary lagoon to "sabkha", while in the outermost part of the platform the existence of a permanent lagoon can be assumed.[13] The facies of this lagoon are muddy and highly bioturbated, with numerous marine organisms colonizing the soft substrate of the lagoon: Lamellibranchs, Gastropods, Brachiopods, with calcareous algae (Palaeodasycladus, Solenopores, etc.) oncoliths and Foraminifers. These levels with large Lamellibranchs (especially "Lithiotidae") are rather rare in the Carixian.[12]

Locations such as Ait Athmane recover the typical Sinemurian-Pliensbachian mediterranean lithiotid bivalve reefs, composed by aggrupation of aberrant bivalves.[14] These "Reefs" had a strong zonation, starting with the bivalves Gervilleioperna and Mytiloperna, restricted to intertidal and shallow-subtidal facies. Lithioperna is limited to lagoonal subtidal facies and even in some low-oxygen environments. Finally Lithiotis and Cochlearites are found in subtidal facies, constructing buildups.[15] Locally, these reefs were developed as shallow subtidal, cross-bedded floatstones, later evolving to layers with evidence of subaerial exposure, including lagoonal marls, and bioturbated red mudstones with root traces and calcrete.[14] These layers are abundant on the aberrant bivalves Lithioperna and Cochlearites, as well common corals, gastropods, the bivalve Opisoma and oncoids, all living in a sheltered lagoon in the interior of the local carbonate platform, similar to the Rotzo Formation of the Trento Platform.[14]

At Ait Bou Guemmez, the upper Aganane Formation records the development of a lagoonal environment south of the Jbel Tizal-Jbel Azourki accident, which evolves to a more or less open subtidal platform environment north of this accident.[16] The local transgressive procession is marked by the dominance of subtidal facies with a microfauna of biozone C1, whereas the high marine level procession is represented by a succession of intertidal to supratidal dolomitic limestones, its top is surmounted by an important subaerial discontinuity materialized by red clay with paleosols and abundant plant roots (e.g. at Tizi n'Terghist).[16] In other localities are mainly biodetritic limestones, showing emersion structures at their top (dolomitization, mud cracks, roots and plant remains, footprints of Dinosaurs).[16]

Paleogeography

Файл:Cycles régressifs de comblement.jpg
Details of some carbonate regressive cycles of filling taken in two geological sections (south rift and High Atlas of Beni Mellal) distant of 230 km

The Aganane Formation is located largely within the "Grand e Accident du Nor d'Altasien" or North Atlas Fault, the largest and most important of the Central High Atlas faults.[10] During the late Pliensbachian, 200 m of carbonate sediments accumulated south of the fault on an overturned block, while to the north more than 700 m of similar material accumulated.[10] This fault line probably marked the northern boundary of a Paleozoic basement peninsula that advanced eastward from the Tichka Massif into the Atlas Trench.[10]

The paleogeographic evolution of our region can be described in three main stages:

  • The Lower Pliensbachian ("Carixian"), which follows the typical Sinemurian paleogeographic pattern with foreshores and prolonged emersion facies (paleosols, karsts and teepee-shaped structures), the latter being mainly observed on the southern slopes of the central High Atlas, evolving on the subtidal platform of the Upper Sinemurian, with the "Lithiotidae" colonizing for the first time the main areas located in line with the active accidents, notably the fault located NE-SW, separating the Tilougguit trough to the SE from its limiting platform to the NW.[11]
  • The "middle" Pliensbachian ("Carixian" - lower "Domerian") marine environment gradually resettles along the western edge of the High Atlas Basin, with maximum opening of depositional environments in the Carixian-Domerian transition (rhythmic mamocalcic sedimentation in the Tilougguit Trench, turbidite facies on the SE edge of the Beni-Mellal platform and subsident lagoons in the other sectors). At the same time, the NW-SE-trending Demnat Fault and the N70-trending North Atlas Fault become evident, whereas the southern edge of the Telouet Graben does not appear to have changed significantly during the Middle Lias like its counterpart in the northern part of the range, being here the main site of the shallow sedimentation of the Aganane Formation.[11] Towards the Tincghir meridian, open sea facies are encountered.[11]
  • The last facies belong to the Upper Pliensbachian (Upper Domerian) where the paleogeography of the Central High Atlas becomes very contrasted, with emersion of a vast sector of the platform (At Demnat), leading to the development of paleosols and karst and the accumulation of lignite deposits along tectonically active faults.[11] At the same time, there is a filling of the Tilougguit ditch by carbonate and terrigenous sedimentation, showing small basins like Tamadout and Taquat N'Agrd with a sedimentation with a gravity component, and shoals (Jbel Taguendouft) with condensed deposits.[11] Finally an intensification of the activity of the North leading to the deepening of the central platform (creation of the new basin of Amezraï), to the individualization of strongly subsident zones in the aplomb of this accident (gutter of Jbel Azourki-Jbel Aroudane) and to the birth of the first wrinkles in the center of the high-Atlasic basin.[11]

Foraminifera

Genus Species Stratigraphic position Material Habitat Notes Images

Everticyclammina[17]

  • Everticyclammina sp.
  • Aganane/Assit Bernai

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Everticyclamminidae family. It represents a species similar to E. virguliana, known from the Middle Jurassic of Morocco.

Haurania[17]

  • Haurania amiji
  • Haurania deserta
  • Aganane
  • Aît Bou Guemez
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Tadghouit
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Hauraniinae family.

Lituosepta[17]

  • Lituosepta recoarensis
  • Lituosepta compressa
  • Aganane
  • Aît Bou Guemez
  • An Blal
  • Assit Bernai
  • Assit Lakhdar
  • Gorges de Taghia
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Nit Blal—Tacht
  • Tadghouit
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Mesoendothyridae family.

Mayncina[17]

  • Mayncina termieri
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Nezzazatoidea family.

Mesoendothyra[17]

  • Mesoendothyra sp.
  • Aganane
  • An Blal
  • Assit Bernai
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Mesoendothyridae family.

Orbitopsella[17]

  • Orbitopsella primaeva
  • Orbitopsella praecursor
  • Aganane
  • Alt Blal
  • Alt Bou Guemez
  • Assif Bernal
  • Assif Lakhdar
  • Assif Imejdag
  • Col d'Adoumaz
  • Col du R'nim
  • Col (Tizi) n-Toudat
  • Gorges du Makin
  • Gorges de Taghia
  • Jbel Choucht
  • Jbel Mahan
  • Jbel Rhat
  • Taclghouit
  • Jbel Tadaghas
  • Jbel Tafenfent
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Mesoendothyridae family.

Pseudocyclammina[17]

  • Pseudocyclammina liasica
  • Alt Blal
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Pfenderinidae family.

Pseudopfenderina[17]

  • Pseudopfenderina butterlini
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Pfenderinidae family.

Siphovalvulina[17]

  • Siphovalvulina sp.
  • Aganane
  • An Blal
  • Assit Bernai
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

A foraminifer of the Pfenderinidae family.

Algae

Genus Species Stratigraphic position Material Habitat Notes Images

Boueina[12]

  • Boueina sp.
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Halimedaceae family.

Cayeuxia[17]

  • Cayeuxia liasica
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Halimedaceae family.

Paleodasycladus[17]

  • Paleodasycladus mediterraneus
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Ibaqalliwn
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Dasycladaceae family.

Pseudolithocodium[12]

  • Pseudolithocodium carpathicum
  • Aganane
  • An Blal
  • Assit Bernai
  • Col du R'nim
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tadaghas
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Thaumatoporellales family.

Sestrosphera[17]

  • Sestrosphera liasina
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Solenoporaceae family. This genus is the most common algal type found in the Biozone A (Lituosepta recoarensis).

Thaumatoporella[17]

  • Thaumatoporella parvovesiculifera
  • Thaumatoporella spp.
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeletons

Marine or Lagoonal

An alga of the Thaumatoporellales family.

Invertebrata

Ichnofossils

Genus Species Location Material Type Made by Notes Images

Arenicolites[12][17]

  • Arenicolites isp.
  • Aganane
  • Alt Blal
  • Alt Bou Guemez
  • Assif Bernal
  • Assif Lakhdar
  • Assif Imejdag
  • Col d'Adoumaz
  • Col du R'nim
  • Col (Tizi) n-Toudat
  • Gorges du Makin
  • Gorges de Taghia
  • Jbel Choucht
  • Jbel Mahan
  • Jbel Rhat
  • Taclghouit
  • Jbel Tadaghas
  • Jbel Tafenfent
  • Jbel Tarkeddid
  • Wazzant

Borrowing Traces

Domichnia

Marine, brackish, or freshwater Unbranched U-shaped burrows, subvertical in orientation, with or without lining and passive infill. Are common in modern coastal environments.

Файл:Arenicolites bedding plane.jpg

Chomatichnus[12][17]

  • Chomatichnus wegberensis

Tubular Fodinichnia

Fodinichnia

Interpreted as the feeding burrow of a sediment-feeding animal.

Chondrites[12][17]

  • Chondrites isp.

Tubular Fodinichnia

Fodinichnia

Burrow-like ichnofossils. Interpreted as the feeding burrow of a sediment-ingesting animal. A more recent study has found that Scoloplos armiger and Heteromastus filiformis, occurring in the German Wadden Sea in the lower parts of tidal flats, make burrows that are homonymous with numerous trace fossils of the ichnogenus.[18]

Файл:Chondrites.JPG
Illustration of Chondrites bollensis

Rhizocorallium[12][17]

  • Rhizocorallium parallelum
  • Rhizocorallium ispp.

Tubular Fodinichnia

Domichnia and/or fodinichnia.

  • Crustaceans
  • Annelids
  • Fishes

Dwelling and feeding burrow of a suspension-feeder or deposit-feeder, associated usually with shallow waters

Файл:Rhizocorallium commune.jpg
Specimens

Skolithos[12][17]

  • Skolithos isp.

Cylindrical to subcylindrical burrows

Domichnia

Burrow-like ichnofossils made by organisms advancing along the bottom surface. Very narrow, vertical or subvertical, slightly winding unlined shafts filled with mud. Interpreted as dwelling structures of vermiform animals; specifically, the domichnion of a suspension-feeding worm or phoronidans

Файл:Skolithos icnofosil ilustracion.jpg
Skolithos ichnofosil reconstruction, with possible fauna associated

Thalassinoides[12][17]

  • Thalassinoides suevicus
  • Thalassinoides isp.

Tubular Fodinichnia

Fodinichnia

Burrow-like ichnofossils. Large burrow-systems consisting of smooth-walled, essentially cylindrical components. Common sedimentary features are Thalassinoides trace fossils in the fissile marlstone to claystone intervals

Файл:Talassinodes illustration.jpg
Thalassinoides burrowing structures, with modern related fauna, showing the ecological convergence and the variety of animals that left this Ichnogenus.

Zoophycos[12][17]

  • Zoophycos isp.

Dwelling traces

Domichnia & Fodinichnia

Burrow-like ichnofossils. It has been related to Echiurans, but also from moving and feeding polychaete worms.

Файл:Zoophycos2.jpg
Example of Zoophycos fossil

Anthozoa

Genus Species Stratigraphic Position Material Notes Images

Ampakabastraea[14]

  • Ampakabastraea sp.
  • Ait Athmane

Calcified skeleton pieces

A Coral of the family Stylinidae.

Archaeosmilia[14]

  • Archaeosmilia beata
  • Archaeosmilia sp.
  • Ait Athmane

Calcified skeleton pieces

A Coral of the family Zardinophyllidae. Late Pliensbachian corals of the Aganane Formation are mainly limited to Retiophyllia, Thamnasteria and Archaeosmilia.

Archaeosmiliopsis[14]

  • Archaeosmiliopsis sp.
  • Ait Athmane

Calcified skeleton pieces

A Coral of the family Archaeosmiliidae.

Oppelismilia[19]

  • Oppelismilia sp.
  • Assemsouk

Calcified skeleton pieces

A Coral of the family Oppelismiliidae.

Phacelostylophyllum[19]

  • Phacelostylophyllum sp.
  • Assemsouk

Calcified skeleton pieces

A Coral of the family Stylophyllidae.

Phacelophyllia[19]

  • Phacelophyllia sp.
  • Ait Athmane

Calcified skeleton pieces

A Coral of the family Dermosmiliidae.

Periseris[19]

  • Periseris sp.
  • Ait Athmane

Calcified skeleton pieces

A Coral of the family Latomeandridae.

Retiophyllia[14]

  • Retiophyllia zizensis
  • Retiophyllia spp.
  • Ait Athmane

Calcified skeleton pieces

A coral of the family Reimaniphylliidae. The phaceloid genus at this site is similar to the common Triassic genus Retiophyllia.

Thamnasteria[14]

  • Thamnasteria cf. mettensis
  • Ait Athmane

Calcified skeleton pieces

A coral of the family Thamnasteriidae.

Demospongea

Genus Species Stratigraphic position Material Notes Images

Cladocoropsis[12]

  • Cladocoropsis mirabilis
  • Aganane
  • An Blal
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Wazzant

Calcareous Skeleton

Marine or Lagoonal

A sponge of the family Cladocoropsidae. Fossils of this and other unidentified sponges are commonly found in reef deposits, associated with corals.

Crustacea

Genus Species Stratigraphic position Material Habitat Notes Images

Parafavreina[12]

  • Parafavreina thoronetensis
  • Parafavreina spp.
  • Aganane
  • Ait Athmane
  • Assemsouk
  • Col du R'nim

Coprolites

Marine, Tidal Flat or Lagoon

Crustacean fossil coprolites, assigned to the ichnofamily Favreinidae. Crustacean coprolites are most abundant in lagoonal deposits, where they are associated with reefs. Possibly coprolites of Thalassinidea

Файл:Mud lobster.jpg

Brachiopoda

Genus Species Stratigraphic position Material Notes Images

Calcirhynchia[20]

  • Calcirhynchia moghrabiensis
  • Calcirhynchia spp.
  • Tizi n’Talrhemt
  • Telouet

Isolated Shells

A Brachiopodan of the family Cirpinae. Relatively abundant on seashore deposits. It was originally identified as part of the genus Rhynchonella

Hesperithyris[20]

  • Hesperithyris atlantis
  • Hesperithyris termieri
  • Hesperithyris reinerii
  • Aïn Kahla
  • Aïn Leuh
  • Almis du Guigou
  • Taïlilout
  • Tazergount
  • Tazioualt
  • Vallée d’Ounila

Isolated Shells

A Brachiopodan of the family Zeilleriidae

Spiriferina[20]

  • Spiriferina betacalcis
  • Spiriferina mediterranea
  • Chebbout bou Hedli

Isolated Shells

A Brachiopodan of the family Spiriferinidae

Tauromenia[20]

  • Tauromenia aretusa
  • Tauromenia polymorpha
  • Tauromenia itoensis
  • Tauromenia brevicostata
  • Col de Talrhemt
  • Ito
  • SW du Jbel Anremeur

Isolated Shells

A Brachiopodan of the family Zeilleriidae

Bivalves

Genus Species Stratigraphic position Material Notes Images

Arcomytilus[21][19]

  • Arcomytilus furcatus
  • Assemsouk
  • Tazioualt

Isolated Shells

A saltwater bivalve of the family Mytilidae.

Cochlearites[14][19][22][21]

  • Cochlearites loppianus
  • Cochlearites spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Tizi n'Tizint

Isolated Shells

A saltwater bivalve of the family Pterioida. A large bivalve, with a subequal shell, that can reach 60–70 cm in height. It is one of the three principal bivalves found on the Lithiotis facies, whose accumulations generally cover megalodontid coquinas.

Eomiodon[21][19]

  • Eomiodon serradensis
  • Eomiodon spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Tizi n'Tizint

Isolated Shells

A saltwater/brackish bivalve of the family Neomiodontidae. This genus is considered an opportunistic suspension feeder of shallow infauna, and the marker genus for brackish environments.[23]

Fimbria[21][19]

  • Fimbria trulla
  • Fimbria spp.
  • Assemsouk
  • Tizi n'Tizint

Isolated Shells

A saltwater bivalve of the family Lucinidae.

Файл:Fimbria soverbii (from Reeve, 1873).png

Gervilleia[20]

  • Gervilleia termieri
  • Gervilleia spp.
  • Tazergount

Isolated Shells

A saltwater bivalve of the family Bakevelliidae.

Gervillioperna[21][19]

  • Gervillioperna atlanta
  • Gervillioperna spp.
  • Ait Athmane
  • Assemsouk

Isolated Shells

A saltwater bivalve of the family Malleidae. Abundant along the rootlets, indicating a very shallow and restricted lagoon or swamp environment

Liogryphaea[24][21][19]

  • Liogryphaea arcuata
  • Liogryphaea spp.
  • Ait Athmane
  • Assemsouk

Isolated Shells

A saltwater bivalve of the family Gryphaeidae. This genus develops a noted material oyster biostrome at Aït Athmane, where a discontinuous, patchy layer is formed, developed under submarine lithification and a relative enrichment in terrigenous matter.[24]

Файл:Liogryphaea arcuata.jpg

Lithioperna[14][22][19]

  • Lithioperna scutata
  • Lithioperna spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid
  • Tizi n'Tizint

Isolated Shells

A saltwater bivalve of the family Pterioida. This genus was founded to be a bivalve with a juvenile byssate stage that developed different lifestyles in adulthood depending on the density of individuals and the firmness of the bottom

Lucina[21][19]

  • Lucina sp.
  • Assemsouk
  • Tizi n'Tizint

Isolated Shells

A saltwater/brackish bivalve of the family Lucinidae. Linked with intertidal settings

Файл:Lucinidae - Lucina species.JPG

Mytiloperna[14][22][19]

  • Mytiloperna spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid

Isolated Shells

A saltwater bivalve of the family Malleidae

Opisoma[14][22][19][24][25]

  • Opisoma menchikoffi
  • Opisoma excavatum
  • Opisoma spp.
  • Ait Athmane
  • Assemsouk
  • Bou Dahar
  • Grand Pic de l'Ouarsenis
  • Tizi n'Tizint

Isolated Shells

A saltwater/brackish bivalve of the family Astartidae. Is considered a genus that evolved from shallow burrowing ancestors, secondarily becoming an edge-lying semi-fauna adapted to photosymbiosis.[25] In the Aganane Formation, this genus is both associated with Corallinaceous facies and tidal flats, even recovered on intertidal channels similar to the ones recovered on modern mangroves

Pachyrisma[22][19][24]

  • Pachyrisma crassa
  • Pachyrisma spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid

Isolated Shells

A saltwater bivalve of the family Pachyrismatidae

Pecten[21][19]

  • Pecten juhanus
  • Assemsouk
  • Tizi n'Tizint

Isolated Shells

A saltwater bivalve of the family Pectinoidae

Файл:Pectinidae - Pecten albicans.JPG

Pholadomya[21][19]

  • Pholadomya scutata
  • Assemsouk

Isolated Shells

A saltwater bivalve of the family Pholadomyidae

Файл:Pholadomya lirata Rombas - 13.JPG

Protodiceras[22][19][24]

  • Protodiceras pumilum
  • Protodiceras spp.
  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid

Isolated Shells

A saltwater bivalve of the family Pachyrismatidae

Gastropoda

Genus Species Stratigraphic position Material Notes Images

Nerinea[21][19]

  • Nerinea spp.
  • Ait Athmane
  • Assemsouk

Isolated Shells

A saltwater gastropod of the family Nerineidae. Local specimens appear to have algal material on the shells, indicating a restricted lagoon environment.

Файл:Fossiile teod (Nerinea).JPG

Pseudonerinea[20]

  • Pseudonerinea terebra
  • Pseudonerinea spp.
  • Tazergount

Isolated Shells

A saltwater gastropod of the family Nerineidae

Scurria[21][19]

  • Scurria spp.
  • Assemsouk

Isolated Shells

A saltwater gastropod of the family Nerineidae. "Scurria" was found in the Assemsouk structure on a "Cochlearites" valve and a shallow ovoid excavation, similar to the resting trace of a limpet, was found inside a transported "Lithiotis".

Файл:Scurria ceciliana ceciliana 002.jpg

Ammonites

Genus Species Stratigraphic position Material Notes Images

Arieticeras[2]

  • Arieticeras ceratitoïdes
  • Arieticeras cf. algovianum
  • Jbel Aït Abess
  • Midelt
  • Zawyat Ahançal

Isolated Shells

An ammonite of the family Hildoceratidae. Arieticeras cf. algovianum is indicative of the Middle Domerian (Upper Pliensbachian) in the upper zone

Fuciniceras[2]

  • Fuciniceras mellahense
  • Fuciniceras volubile
  • Beni-Mellal

Isolated Shells

An ammonite of the family Hildoceratidae

Seguenziceras[2]

  • Seguenziceras cf.algovianum
  • Tamsift

Isolated Shells

An ammonite of the family Polymorphitidae

Tropidoceras[2]

  • Tropidoceras cf. demonense
  • Tropidoceras spp.
  • Ifrane

Isolated Shells

An ammonite of the family Polymorphitidae

Uptonia[2]

  • Uptonia jamesoni
  • Uptonia spp.
  • Tazioualt

Isolated Shells

An ammonite of the family Polymorphitidae

Файл:Ammonite - Uptonia jamesoni.jpg

Annelida

Genus Species Stratigraphic position Material Habitat Notes Images

Serpulidae[12]

Indeterminate

  • Aganane
  • An Blal
  • Ait Athmane
  • Assemsouk
  • Assit Bernai
  • Gorges du Tisakht
  • Jbel Choucht
  • Jbel Rhat
  • Jbel Tarahalt
  • Jbel Tarkeddid

Calcareous skeleton

Marine or Lagoonal

A Sabellida of the family Serpulidae. These annelids are found as well in the reef facies as in the lagoon deposits

Файл:Ver de la famille des Serpulidae à identifier.jpg

Dinosaur Tracks

Theropoda

Genus Species Stratigraphic position Material Notes Images

Anchisauripus[1][26][27]

  • Anchisauripus isp.
  • Aït Blal
  • Akourbi
  • Assif-n-Sremt
  • Issil-n-Aït Arbi tracksite
  • Tabant

Footprints

Traces of theropods, members of the ichnofamily Anchisauripodidae, incertae sedis within Neotheropoda. Attributed to dinosaurs of type Coelophysidae

Файл:Procompsognathus.jpg
The prints of Anchisauripus belong to a genus similar to that of Procompsognathus

Argoides[26][1][27]

  • Argoides isp.
  • Aït Blal
  • Assif-n-Sremt
  • Ibaqualiwn
  • Iskatafene

Footprints

Theropod tracks, member of the ichnofamily Anchisauripodidae, incertae sedis inside Neotheropoda. Mistaken originally as coelurosaur tracks, this specimens have pes that resemble those of Noasaurids and other Abelisauroids.[28] Includes a pathologic trackway with evidence of limping, as well three morphotypes: Didactyl, tridactyl and tetradactyl theropod trackways.[1]

Файл:Velocisaurus.jpg
The footprints of Argoides belong to a genus with a pes similar to Velocisaurus, yet does not implicate is a member of the family or a relative

Carmelopodus[26][27]

  • Carmelopodus isp.
  • Ibaqualiwn
  • Tizi-n-Aït

Footprints

Theropod tracks, member of the ichnofamily Eubrontidae, incertae sedis inside Theropoda. Ceratosaur tracks. Includes the largest theropod track from the Early Jurassic of Morocco.[28]

Файл:Cerato. nasicornis PUT 500.JPG
The footprints of Carmelopodus belong to a genus with a pes similar to Ceratosaurus, yet does not implicate is a member of the family or a relative

Eubrontes[29]

  • Eubrontes isp.
  • Aït Blal
  • Aït Kelelch
  • Assif-n-Sremt
  • Tizi-n-Aït
  • Waougoulzat

Footprints

Theropod tracks, type member of the ichnofamily Eubrontidae, incertae sedis inside Theropoda. Eubrontes is related to the Genus Dilophosaurus, representing a basal Neotheropods.

Файл:Cast of Eubrontes Gigantis track by Paul Olsen.jpg

Grallator[1][26][30]

  • Grallator tuberosus
  • Grallator variabilis
  • Grallator isp.
  • Akourbi
  • Aït Blal
  • Ansous
  • Assif-n-Sremt
  • Ibaqualiwn
  • Issil-n-Aït Arbi
  • Tabant
  • Sidi Moussa tracksite
  • Waougoulzat

Footprints

Theropod tracks, typical member of the ichnofamily Grallatoridae, incertae sedis within Theropoda. Attributed to dinosaurs of type Coelophysidae and Dilophosaurus

Файл:Rutgers University Geology museum prehistoric dinosaur named grallator.JPG

Megalosauripus[26][27]

  • Megalosauripus isp.
  • Akourbi
  • Ibaqualiwn
  • Talsnant
  • Tizi-n-Aït

Footprints

Traces of theropods, members of the ichnofiber family Eubrontidae, incertae sedis within Theropoda. Traces of tetanurans, some with a resemblance to Allosauroids.[28]

Файл:202009 Allosaurus fragilis.png
The footprints of Megalosauripus belong to a genus with a pes similar to Allosaurus, yet does not implicate is a member of the family or a relative

Plesiornis?[1]

  • Plesiornis? isp.
  • Aït Blal

Footprints

Traces of theropods, members of the ichnofamily Anchisauripodidae, incertae sedis within Neotheropoda. Theropods with bird-like legs or similar to that of Coelurosaurs

Theropodipedia[26][1][30]

  • Theropodipedia ichnog. indeterminate
  • Akourbi
  • Aït Blal
  • Ansous
  • Ibaqualiwn
  • Iba Ziz
  • Issil-n-Aït Arbi
  • Tabant
  • Sidi Moussa
  • Waougoulzat

Footprints

Theropod Tracks of uncertain affinity

Sauropodomorpha

Genus Species Stratigraphic position Material Notes Images

Breviparopus[26][31]

  • Breviparopus isp.
  • Ibaqalliwn

Footprints

Traces of sauropods, typical member of the ichnofamily Parabrontopodidae, incertae sedis within Sauropodomorpha. Includes traces with pes similar to Diplodocoidea.[31][32]

Файл:Amphicoelias17DB2.jpg
The footprints of Breviparopus belong to a genus with a similar pes to that of Amphicoelias, yet it doesn´t mean is from a Neosauropod

Eosauropus[26][31]

  • Eosauropus isp.
  • Assif-n-Sremt
  • Ibaqalliwn

Footprints

Traces of sauropods, typical member of the ichnofamily Parabrontopodidae, incertae sedis within Sauropodomorpha. Includes traces with pes similar to those of Blikanasaurus.[32]

Файл:Eosauropus cast fruita.jpg

Otozoum[33][34]

  • Otozoum moodii
  • Otozoum isp.
  • Assif-n-Sremt
  • Ibaqalliwn
  • Issil-n-Aït Arbi
  • Timit

Footprints

Traces of sauropodomorphs, a type member of the ichnofamily Otozoidae, incertae sedis within Sauropodomorpha. Includes a gigantic 84 or 75 cm track that represents the largest Otozoum ever described in the literature.[34]

Файл:Lamplughsaura BW.jpg
The local Footprints of Otozoum may have belonged to a genus similar to that of Lamplughsaura

Parabrontopodus[31]

  • Parabrontopodus isp. A
  • Parabrontopodus isp. B
  • Parabrontopodus isp. C
  • Assif-n-Sremt
  • Aguer-n-Ouzrou
  • Aguerd
  • Ibaqalliwn
  • Tabant
  • Tigharguenine
  • Tizi-n-Aït
  • Waougoulzat

Footprints

Traces of sauropods, typical member of the ichnofamily Parabrontopodidae, incertae sedis within Sauropodomorpha. Includes tracks with pes similar to those of Vulcanodon (perhaps left by Tazoudasaurus?) and other morphotype more similar to Rhoetosaurus.[32]

Файл:Vulcanodon NT.jpg
The Footprints of Parabrontopodus may have belonged to a genus similar to that of Vulcanodon

Pseudotetrasauropus[33]

  • Pseudotetrasauropus isp.
  • Issil-n-Aït Arbi

Footprints

Traces of sauropodomorphs, a type member of the ichnofamily Otozoidae, incertae sedis within Sauropodomorpha.

Файл:Leonerasaurus NT.jpg
The prints of Pseudotetrasauropus may have belonged to a genus similar to that of Leonerasaurus

Sauropodomorphidia[33][30]

  • Sauropodomorphidia ichnog. indeterminate
  • An
  • Assif-n-Sremt
  • Jbel Azourki
  • Ibaqalliwn
  • Iba'ziz
  • Issil-n-Aït Arbi
  • Tabant
  • Tizi-n-Aït
  • Tigharguenine
  • Timit tracksite

Footprints

Sauropodomorph tracks of uncertain affinity

Sauropodina[26][27]

  • Sauropodina ichnog. indéterminé
  • Ahbak
  • Ait Waggown
  • Ansous
  • Assif-n-Sremt
  • Tizi-n-Aït
  • Tabant
  • Timit
  • Iba'ziz
  • Tigharguenine
  • Waougoulzat

Footprints

Sauropod tracks of uncertain affinity

Файл:Traces dino géant.jpg
Metric tracks of a giant sauropod dinosaur, at the top of an emersive "shallowing upward" carbonate cycle

Ornithischia

Genus Species Location Material Notes Images

Deltapodus?[35]

  • Deltapodus? isp.
  • Ansous tracksite

Footprints

Thyreophoran tracks, type member of the ichnofamily Moyenisauropodidae, incertae sedis inside Neornithischia. Is considered synonymous with the ichnogenus Anomoepus. The tracks adscribed resemble basal Thyreorphora feet. The tracks related to the genus are vinculated with genera such as Scelidosaurus, whose fossils have been found on Pliensbachian strata of England. Due to it´s morphology, this tracks have been latter identified as possible Deltapodus, yet this does not mean they are of Stegosaur origin.[36]

Файл:Scelidosaurus harrisonii.png
Scelidosaurus, one of the best known Early Jurassic Thyreophorans, matches with the bodyplan assigned to the ichnogenus Moyenisauropus

Photo Gallery

See also

References

Шаблон:Reflist

  1. 1,0 1,1 1,2 1,3 1,4 1,5 1,6 Шаблон:Cite journal
  2. 2,0 2,1 2,2 2,3 2,4 2,5 Шаблон:Cite journal
  3. 3,0 3,1 Шаблон:Cite journal
  4. 4,0 4,1 4,2 Шаблон:Cite journal
  5. 5,0 5,1 Шаблон:Cite journal.
  6. Шаблон:Cite journal.
  7. Шаблон:Cite journal
  8. Шаблон:Cite journal
  9. 9,0 9,1 9,2 Шаблон:Cite journal
  10. 10,0 10,1 10,2 10,3 10,4 10,5 Шаблон:Cite journal
  11. 11,0 11,1 11,2 11,3 11,4 11,5 11,6 11,7 11,8 11,9 Шаблон:Cite journal.
  12. 12,00 12,01 12,02 12,03 12,04 12,05 12,06 12,07 12,08 12,09 12,10 12,11 12,12 12,13 12,14 12,15 Шаблон:Cite journal.
  13. Шаблон:Cite journal.
  14. 14,00 14,01 14,02 14,03 14,04 14,05 14,06 14,07 14,08 14,09 14,10 14,11 Шаблон:Cite journal
  15. Шаблон:Cite journal
  16. 16,0 16,1 16,2 Шаблон:Cite journal
  17. 17,00 17,01 17,02 17,03 17,04 17,05 17,06 17,07 17,08 17,09 17,10 17,11 17,12 17,13 17,14 17,15 17,16 17,17 17,18 17,19 Шаблон:Cite journal
  18. Шаблон:Cite journal
  19. 19,00 19,01 19,02 19,03 19,04 19,05 19,06 19,07 19,08 19,09 19,10 19,11 19,12 19,13 19,14 19,15 19,16 19,17 19,18 19,19 Шаблон:Cite journal
  20. 20,0 20,1 20,2 20,3 20,4 20,5 Шаблон:Cite journal.
  21. 21,00 21,01 21,02 21,03 21,04 21,05 21,06 21,07 21,08 21,09 21,10 Шаблон:Cite journal
  22. 22,0 22,1 22,2 22,3 22,4 22,5 Шаблон:Cite journal
  23. Шаблон:Cite journal
  24. 24,0 24,1 24,2 24,3 24,4 Шаблон:Cite journal
  25. 25,0 25,1 Шаблон:Cite journal
  26. 26,0 26,1 26,2 26,3 26,4 26,5 26,6 26,7 26,8 Шаблон:Cite journal
  27. 27,0 27,1 27,2 27,3 27,4 Шаблон:Cite journal
  28. 28,0 28,1 28,2 Шаблон:Cite book
  29. Шаблон:Cite journal
  30. 30,0 30,1 30,2 Шаблон:Cite journal
  31. 31,0 31,1 31,2 31,3 Шаблон:Cite journal
  32. 32,0 32,1 32,2 Шаблон:Cite journal
  33. 33,0 33,1 33,2 Шаблон:Cite journalШаблон:Dead linkШаблон:Cbignore
  34. 34,0 34,1 Шаблон:Cite journal
  35. Шаблон:Cite journal
  36. Шаблон:Cite journal