Azilal Group
The after-effects of the Toarcian Oceanic Anoxic Event are also very present in the marginal marine strata of the Tafraout Group, with the Toksine Section recording a dramatic collapse on the scale of the Tethys of the neritic carbonate system.
Geology
The Central High Atlas of Morocco is part of a mountain belt formed by the inversion of a rift from the Triassic-Jurassic periods, due to Cenozoic tectonic activity. The region's structure comes from four main tectonic phases: the pre-rift phase tied to the formation of Pangaea, the syn-rift phase during the Late Permian to Late Triassic, influenced by the opening of the Atlantic Ocean and Tethys Ocean, and the post-rift phase, where Jurassic-Cretaceous carbonate platforms formed. The High Atlas has thrust and oblique-slip faults from W-E to NE-SW. It is an intracontinental mountain range resulting from the uplift of a large Mesozoic rift system. Triassic to Cretaceous layers are confined within basins, controlled by extensional rift structures. Sedimentation in these basins varied, with marine shales and limestones in the east and fluvial deposits in the west. Several tectonic events during the Triassic-Jurassic boundary reactivated normal faults, leading to the dominance of marls during the Middle Liassic to Toarcian.
Description
"Amezraï" Formation
This formation, found in the Amezraï minibasin and linked to the Tazoult Ridge, dates to the Earliest Toarcian and is identified by brachiopod fossils. It includes sandstones, marls, and biodetrital or oolitic limestones, with layers varying from centimeters to up to 6 meters thick. The lower part consists of conglomerates, sandstones, and clays, transitioning to limestones and marls at the top. Ripple structures and cross-bedding are common in sandstone layers, while reworked horizons appear in the limestone. The formation reflects a subtidal to supratidal environment, with some layers suggesting lagoonal conditions and reduced carbonate content compared to older formations. Local tectonic activity, mainly due to seismic events in the Tethyan region, influenced the formation, causing erosion of older Paleozoic layers.
Azilal Formation
Tafraout Formation
The Tafraout Formation consists of oolitic and biodetrital limestones with cross-stratifications, found in channels and bars, alongside greenish marls and micro-conglomerates. These layers were deposited on a coastal platform. The formation is mainly made of sandstones, marls, and ooid limestones, different from older layers. Common fossils include bivalves, brachiopods, gastropods, corals, and echinoderms, with plant remains in some sandstones. The rocks formed in environments ranging from supratidal to subtidal, characterized by tropical conditions akin to those observed on Andros, Bahamas. The upper part of the formation shows sediments filling an old Pliensbachian basin, moving from deeper marine conditions to a supratidal coastal plain. Fossils and sediment features suggest a challenging environment, with alternating sandstone and marl layers indicating changes in water depth and sedimentation patterns.
Tagoudite Formation
The Tagoudite Formation marks a major shift in Liassic sedimentation, replacing the carbonate turbidites of the Ouchbis Formation with mostly siliciclastic layers. These layers alternate between gray and green sandstone, sandy marls, and siltstones, forming sequences up to 20 meters thick. They show a decrease in grain size and an increase in marl content from bottom to top, with features like ripple marks and laminations. Microscopically, the turbidites are mainly fine silt, with varying amounts of quartz, feldspar, and carbonate detritus, and occasional pyrite. This formation suggests an open marine environment with sediment interruptions and materials coming from distant areas. It is widespread in the Central High Atlas, with thicknesses reaching up to 320 meters, and varies across different regions like Tounfite and Beni Mellal. In the Central Middle Atlas, sedimentation was interrupted by emersion before the formation's deposition.
Paleogeography
The Tafraout Group was formed on the Moroccan Carbonate Platform during a sea-level rise in the Early Toarcian, linked to the Toarcian Oceanic Anoxic Event, at a palaeolatitude between 19°-20°N, around the same latitude as modern Mauritania or Cuba, situated between ancient geological regions like the West Moroccan Arch, the Anti-Atlas and the Sahara craton, developed after a major sea regression, with red clays and conglomerates filling small basins in the Atlas region.
Two main stages mark the area's evolution: during the Lower Toarcian, deposition patterns from the earlier Pliensbachian continued, followed by terrigenous materials filling the basins and stopping temporally the carbonate production. It evolved along several depocenters and associated accidents, the southern edge of the Tilougguit Syncline in the north to the axis of the Aït Bouguemmez Basin in the south, showed that the depocenter zone corresponded to the disposal area located between the Talmest-Tazolt Ridge to the North and the North-Atlasic accident to the South. This terrestrial lithology is mostly found in the small basins in tearing in the Atlas of Telouet, Toundoute, Afourer and Azilal, having the Demnat Accident as the major structural element in this last sector. While at this W areas it becames fully terrestrial/intertidal, at other areas like Beni Mellal, Dadès Gorges or Zaouiat Ahansal marine influences are seen in a carbonate-siliclastic regime. By the Middle Toarcian-Aalenian, the Azilal Formation expanded eastward, with isolated carbonates forming in the Amezraï basin, surrounded by terrigenous sediments. This period is marked by the individualization of thein the center of the basin and by a relative tectonic calm in the other coeval sectors.
Marine fossils like brachiopods and ammonites help date the sediment layers and confirm the transition from marine to expansive E terrestrial environments during the Middle Toarcian. The deposition starts with a marked break of the Carbonate production and a major regression in the Lowermost Toarcian, then oscilated Transgresive/Regresive cycles in the Laevisoni-Bifrons substages, followed finally by a post Bifrons major regression and full return to the Carbonate production. The Tafraout Platform deepened over time, signaling a shift to transgressive conditions even with the expansion of W continental facies. On the Amezraï Formation basin the fauna is composed by brachiopods such as Soaresirhynchia bouchardi, S. babtisrensis and Pseudogibbirhynchia jurensis that corroborate the Earliest Toarcian age for it and adjacent layers. Meanwhile, the presence of Aalenian (Bradfordernsis-Murchinsonae) Branchiopods in the Azilal Formation coeval with Ammonites of the same age at the Ikerzi Area confirms the marine delimitation in the last stages of deposition. In the Azilal system, the "Tafraout Platform" saw a deepening towards the uppermost layers, teasing the transition to the Bin El Ouidane transgressive Carbonate Platform facies, while the lower sequences, with fine conglomerate layers and plant remains indicate a proximal delivery area and the peak of the regression, with many microlagoons that formed between the large coral patch reefs are documented by micrite and partially leached micrite.
Paleoenvironment
The Tafraout Group covers most of the W High Atlas, surrounded by highlands that probably hosted dry cool (10.6 °C) to humid climate (12.30 °C), with a succession rain tundra to wet forest environments, as proven by samples from coeval layers in the External Rif Chain. The Continental/Tidal Flat Azilal Formation, within this group, was deposited in coastal environments influenced by rivers, tidal flats, and paralic settings, rwith eworked material and in Toundoute unique interbedded Explosive eruption-type volcanic material, generally constituting more than half of the detrital components, showing clear carbonate recrystallization, suggesting that these fragments were still at high temperature during deposition and, therefore, contemporaneous with the sedimentation, probably as a result of early activity in the local South-Atlasic Fault. Fauna, including rare brachiopods and bivalves, alongside sedimentary features like ripple marks and rain imprints, indicate a mix of marine and continental conditions, with evidence of emersions. The environment shifted from coastal facies in the north to fluvial facies in the south, and tectonic activity affected sediment deposition. The flow of the fluvial-washed sediments take place in a E-NE direction, being moved to the layers of the Amezräi, Tagoudite & Tafraout Formations and other coeval marine units, as well are found on fluviatile channels inside the own rocks of this unit.
The Azilal Formation also saw high plant activity, with remains such as wood, charcoal, and rhizoliths, indicating nearby vegetated soils. Fluvial systems transported sediment from Paleozoic and Triassic sources, with volcanic material also present, suggesting active volcanic processes during deposition. The warm, alternating wet and dry climate led to the formation of soils with calcareous nodules and gypsum in arid zones, particularly in areas like Toundoute and Telouet.
During the Lower Toarcian, a shift to siliciclastic deposits occurred, marked by storm events and increased plant debris, indicating a warm, humid climate. Some areas, especially near the coast, resembled modern Sabkha (like those in the Persian Gulf). The Tafraout Formation, meanwhile, represented marginal marine environments with diverse marine fauna, including coral reefs and "lithiotid" (Plicatostylidae aberrant reef-forming) bivalves.
The Toarcian Oceanic Anoxic Event (T-OAE) intensified Tropical storms, destroying older carbonate platforms and increasing siliciclastic deposits, which contributed to the formation of the Tafrout environment. Additionally, after the T-OAE, ecosystems in areas like Jebel Toksine began to recover with new carbonate activity and diverse marine life, including bivalves and other reef organisms.
The aftermath of the T-OAE is visible in the lower Azilal Formation, showing a slow recovery of marine environments. There is also evidence of a Middle Toarcian cold snap, followed by a return to warmer conditions. The eastern and northeastern High Atlas saw the development of carbonate sedimentation, with reefs and marine fossils indicating tectonic activity during the Late Toarcian.
The central High Atlas region features long diapirs and minibasins formed during early Jurassic rifting, with the Tazoult Ridge being a key example. Diapir movement shaped the surrounding rock layers, while local sedimentation reflects changes in climate, including wetter periods linked to increased erosion. Sharp geological boundaries mark the closure of salt walls during diapir growth, and ancient environments here resembled modern shallow waters like the Red Sea. Charcoal remnants suggest coastal forests or mangroves existed during wetter times.
Biota
Foraminifera
Genus | Species | Location | Formation & Age | Material | Habitat | Notes | Images |
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Ammobaculites |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Ammomarginulininae. | |
Dentalina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Nodosariinae. | |
Everticyclammina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the Everticyclamminidae family. It represents a species related to E. virguliana, known from the Middle Jurassic of Morocco | |
Citharina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Vaginulininae. It represents a species related to E. virguliana, known from the Middle Jurassic of Morocco | |
Glomospira |
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Calcareous Skeleton | Shoreface to Open Marine | A foraminifer of the family Ammodiscidae. | |
Glomospirella |
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Calcareous Skeleton | Shoreface Marine | A foraminifer of the family Ammovertellininae. | |
Haurania |
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Calcareous Skeleton | Shoreface Marine | A foraminifer of the family Hauraniinae. | |
Ichtyolaria |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Ichthyolariinae. | |
Lenticulina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | Un foraminifère de la famille des Lenticulininae. | |
Lingulina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Lenticulininae. | |
Marginulina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Marginulininae. | |
Nodosaria |
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Calcareous Skeleton | Shoreface to Open Marine | A foraminifer of the family Nodosariinae. | |
Ophtalmidium |
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Calcareous Skeleton | Shoreface to Open Marine | A foraminifer of the family Ophthalmidiidae. | |
Orbitopsella |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Orbitopsellinae. | |
Pseudocyclammina |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Hauraniidae. | |
Placopsilina |
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Calcareous Skeleton | Open Marine | A foraminifer of the family Placopsilinidae. | |
Pseudonodosaria |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Nodosariinae. | |
Reinholdella |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A foraminifer of the family Ceratobuliminidae. | |
Siphovalvulina |
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Calcareous Skeleton | Shoreface to Open Marine | A foraminifer of the family Pseudopfenderininae. | |
Spirillina |
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Calcareous Skeleton | Shoreface to Open Marine | A foraminifer of the family Spirillinidae |
Marine Palynomorphs
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Botryococcus |
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Miospores | Member of the family Botryococcaceae inside Trebouxiales. | |
Carinolithus |
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Calcareous Skeletons | Member of the family Calyculaceae inside Parhabdolithaceae. | |
Luehndea |
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Cysts | A Dinoflagellate cyst, type member of Luehndeoideae. Constitutes an excellent marker of
the Pliensbachian-Toarcian interval. |
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Mancodinium |
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Cysts | A Dinoflagellate cyst, type member of Mancodiniaceae. Dominant genera on some layers of the Lias Delta Stage. | |
Mendicodinium |
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Cysts | A Dinoflagellate cyst, member of Dinophyceae. | |
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Cysts |
A member of Prasinophyceae. The presence of this genus indicates fresh or brackish water inputs in the depositional environment |
"Algae"
Genre | Species | Location | Formation & Age | Material | Habitat | Notes | Images |
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Cayeuxia |
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Calcareous Skeleton | Shallow Marine/Lagoonal | A green algae of the Halimedaceae or Udoteaceae family. |
Invertebrates
In the Tafraout Group, the fossil record of units like the Azilal Formation is very restrictive compared to the marine coeval/underliying units like the Amezraï or Tafraout Formations. In the Dadés area Coral patch reefs rarely occur in the middle of the unit with associated echinodems (Sea urchin spines, Crinoid fragments) lamellibranchs, gastropods, solitary corals and algae. Plant remains are very abundant in places such as the north of Jbel Akenzoud and partly impregnated and/or carbonized by malachite. Gastropods have been discovered in several places, but none of the specimens have been studied nor identified. Beds with large accumulations of unidentified Ostracod valves on an endemic thin level of green marl are found at the Beni-Mellal area (Adoumaz & Col de Ghnim outcrops). The tubes of serpulid worms are known from Jbel Toksine, in relation to the bivalve pavements.
Color key
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Notes Uncertain or tentative taxa are in small text; |
Ichnofossils
Genus | Species | Location | Formation & Age | Material | Type | Made by | Images |
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Arenicolites |
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Traces of habitation | Domichnia |
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Chondrites |
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Tubular Fodinichnia | Fodinichnia |
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Rhizocorallium |
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Tubular Fodinichnia | Domichnia or fodinichnia |
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. |
Scolicia |
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Locomotion or feeding trace | Fodinichnia |
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Skolithos |
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Cylindrical to subcylindrical burrows | Domichnia |
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. |
Thalassinoides |
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Tubular Fodinichnia | Fodinichnia |
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. |
Zoophycos |
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Traces of habitation | Domichnia & Fodinichnia |
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Anthozoa
The platform patch reefs in the Tafraout area are notable for their biodiversity, with some reaching heights of up to 40 m and lengths of up to 80 m, representing massive biostromes with a varied associated fossil assemblage, including bivalves, gastropods, echinoderm fragments, solitary corals, and bryozoans, found among the coral patchs. Massive reef pinnacles are recovered at Anergui and northern flank of Tassent, while rarer ones are know from Bou Zemou.
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Actinaraea? |
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Calcified Skeletal Pieces | A coral of the family Actinacididae. | |
Ampakabastraea |
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Calcified Skeletal Pieces | A coral of the family Stylinidae. | |
Archaeosmilia |
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Calcified Skeletal Pieces | A coral of the family Zardinophyllidae. These solitary corals were observed throughout the lower unit biostromes. | |
Archaeosmiliopsis |
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Calcified Skeletal Pieces | A coral of the family Archaeosmiliidae. | |
Enallhelia? |
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Calcified Skeletal Pieces | A coral of the family Stylinidae. | |
Haimeicyclus |
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Calcified Skeletal Pieces | A coral of the family Oppelismiliidae. | |
Hispaniastraea |
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Calcified Skeletal Pieces | A coral of the family Hispaniastraeidae. | |
Lophelia? |
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Calcified Skeletal Pieces | A coral of the family Carophylliidae. | |
Myriophyllum |
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Calcified Skeletal Pieces | A coral of the family Oppelismiliidae. | |
Phacelostylophyllum |
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Calcified Skeletal Pieces | A coral of the family Stylophyllidae. | |
Phacelophyllia |
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Calcified Skeletal Pieces | A coral of the family Dermosmiliidae. | |
Periseris |
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Calcified Skeletal Pieces | A coral of the family Latomeandridae. | |
Spongiocoenia |
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Calcified Skeletal Pieces | A coral of the family Stylophyllidae. | |
Thecactinastraea |
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Calcified Skeletal Pieces | A coral of the family Oppelismiliidae. |
Brachiopoda
Genre | Species | Location | Formation & Age | Material | Notes | Images |
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Gibbirhynchia |
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Isolated shells | A brackish/marine Tetrarhynchiidae (Brachiopod) | |
Quadratirhynchia |
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Isolated shells | A brackish/marine Tetrarhynchiidae (Brachiopod) | |
Homoeorhynchia |
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Isolated shells | A brackish/marine Rhynchonellinae (Brachiopod). Homoeorhynchia meridionalis indicates the Toarcian Serpentinus zone and base of the Bifrons zone | |
Liospiriferina |
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Isolated shells | A brackish/marine Spiriferinidae (Brachiopod) | |
Pseudogibbirhynchia |
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Isolated shells | A brackish/marine Pamirorhynchiinae (Brachiopod). | |
Soaresirhynchia |
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Isolated shells | A brackish/marine Basiliolinae (Brachiopod) | |
Sphaeroidothyris |
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Isolated shells | A brackish/marine Lobothyrididae (Brachiopod) | |
Stroudithyris |
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Isolated shells | A Brackish/marine Lissajousithyrididae (Brachiopod). Mostly benthonic specimens are known. The presence of this species indicates an upper Toarcian-Aalenian age for the layers where was discovered. | |
Telothyris |
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Isolated shells | A brackish/marine Lobothyrididae (Brachiopod). Relatively abundant on seashore deposits. Includes juvenile forms of Telothyris jauberti, present on benthic deposit strata. |
Bivalves
Genre | Species | Location | Formation & Age | Material | Notes | Images |
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Chlamys |
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Isolated Shells | A Pectinidan, member of the family Pectinidae | |
Cochlearites |
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Isolated shells | A brackish/marine Plicatostylidae (Bivalve). A large bivalve, with a subequivalent shell, reaching 60–70 cm high. It is one of the three main bivalves found on the Lithiotis Facies, whose accumulations generally cover megalodontid coquinas. | |
Gervillioperna |
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Isolated shells | A brackish/marine Plicatostylidae (Bivalve). Abundant along rootlets, indicating a very shallow and restricted lagoon or marsh environment | |
Lithioperna |
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Isolated shells | A brackish/marine Plicatostylidae (Bivalve). This genus was founded to be a bivalve with a byssate juvenile stage that developed different lifestyles as adults depending on the density of the individuals and the firmness of the bottom | |
Pachygervillia |
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Isolated shells | A brackish/marine Plicatostylidae (Bivalve). | |
Opisoma |
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Isolated shells | A brackish Astartidae (Bivalve). Is considered a genus that evolved from shallow-burrowing ancestors, secondarily becoming an edge-prone semi-fauna adapted to photosymbiosis. | |
Trichites |
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Isolated shells | A marine Pinnidae (Bivalve) | |
Pholadomya |
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Isolated shells | A marine Pholadomyidae (Bivalve) | |
Spondylus |
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Isolated Shells | A marine member of the family Spondylidae |
Gastropoda
Multiple Gasteropodan faunas are know, specially associated with coral patch reefs, but lack proper studies.
Genre | Species | Location | Formation & Age | Material | Notes | Images |
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Nerinea |
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Isolated shells | A Nerineoidean, member of the family Nerineidae | |
Neritodomus |
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Isolated Shells | A Cycloneritidan, member of the family Neridomidae | |
Platyacra |
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Isolated Shells | A Trochoidean, member of the family Angariidae | |
Purpurina |
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Isolated Shells | A Caenogastropodan, member of the family Purpurinidae | |
Scurriopsis |
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Isolated shells | A Lottioidean, member of the family Acmaeidae |
Ammonites
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Alocolytoceras |
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Isolated shells | An Ammonite of the family Lytoceratidae. | |
Calliphylloceras |
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Isolated shells | An Ammonite of the family Calliphylloceratinae | |
Canavaria |
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Isolated shells | An Ammonite of the family Hildoceratidae. | |
Dactylioceras |
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Isolated shells | An Ammonite of the family Dactylioceratidae. The basis of this series is based on a regional discontinuity marked by a remarkable abundance of Eodactylites from the Lower Toarcian | |
Eleganticeras |
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Isolated shells | An Ammonite of the family Hildoceratidae. | |
Harpoceras |
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Isolated shells | An Ammonite of the family Hildoceratidae. | |
Hildaites |
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Isolated shells | An Ammonite of the family Hildoceratidae. | |
Hildoceras |
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Isolated shells | An Ammonite of the family Hildoceratidae. Characteristics of the base of the area in Bifrons | |
Lytoceras |
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Isolated shells | An Ammonite of the family Lytoceratidae. | |
Neolioceratoides |
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Isolated shells | An Ammonite of the family Hildoceratidae. | |
Praepolyplectus |
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Isolated shells | An Ammonite of the family Hildoceratidae. |
Crustacea
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Polycope |
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Isolated Valves | A marine/brackish Polycopidae (Ostracoda). Present with large accumulations of specimens |
Echinodermata
Multiple echinoderm remains, including Crinoid articulated and fragmentary specimens and indeterminate echinoid fragments, are know from several localities, usually associated with large coral bioherms or sea trangressions.
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Arbacioida | Indeterminate |
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Complete specimens and isolated parts of the exoskeleton | A marine Arbacioida (Echinoidean). These sea urchins are the most abundant echinoderms on local lithiolid reefs. | |
Pentacrinites |
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Complete specimens and isolated parts of the exoskeleton | A Crinoid of the family Pentacrinitidae |
Vertebrates
Several scales & teeth of fishes (Lepidotes?) are know from several locations, coming from freshwater/lagoonal layers. Indeterminate dinosaurian & other vertebrates are know from Mizaguène Hill, Taouja Ougourane, Aït Ouaridène, Oued Rzef & Jbel Remuai in the Azilal Province. Some of them are recovered in a "Bone bed" and others are associated with abundant plant remains.
Actinopteri
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Leptolepis |
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Marine, brackish or freshwater bony fish of the family Leptolepidae. Recovered from the Tagoudite Formation, represents a genus of cosmopolitan fish, common in the Toarcian Mediterranean area. Most specimens appear to come from lagoonal facies. |
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Leptolepididae |
Indeterminate |
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Marine or brackish bony fish of the family Leptolepidae. |
Dinosauria
Plantae
The vegetation in the Toundoute area is compared to that of the Isle of Pines. Paleosols in these regions show many plant roots (Rhizoliths) and heavily disturbed layers. Plant remains include coal, leaves, woody roots, rhizoliths, fossil wood, and other plant debris. In Toundoute, small plant fragments, mostly fern leaflets and some cycad leaves, were found, with wood debris resembling conifers like Pinaceae or Taxaceae. Ferns seem to have dominated the vegetation, likely in wetlands, followed by cycads and conifers. Similar plants have been found in Egypt's Mashabba Formation. At Jebel Toksine, woody plant debris, including charcoal, suggests vegetation in a humid, marginal marine environment. Jebel Azourki has layers of shales with coal streaks and plant fragments, possibly representing a marsh in a lagoon area.
Palynology
Phytoclasts, spores, pollen and Tasmanites algae indicate that the palaeoenvironment of the lower Toarcian Amellago area was likely proximal continental shelf with a high terrestrial input, and notorious influence of brackish water in the depositional environment.
Genus | Species | Location | Formation & Age | Material | Notes | Images |
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Alisporites |
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Pollen | Affinities with the families Peltaspermaceae, Corystospermaceae or Umkomasiaceae inside Peltaspermales. | |
Callialasporites |
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Pollen | Affinities with Araucariaceae inside Coniferae. | |
Classopollis |
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Pollen | Affinities with Cheirolepidiaceae inside Coniferae. This interval is numerically dominated by Classopollis, which usually accounts for more than 60.95% of the palynomorphs present | |
Kraeuselisporites |
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Spores | Affinities with Selaginellaceae and probably Lycopsida. Age indicator, also present on nearby regions | |
Ischyosporites |
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Spores | Affinities with Incertade sedis Pteridopsida or alternatively with Schizaeaceae/Anemiaceae. | |
Quadraeculina |
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Pollen | Affinities with Podocarpaceae or Pinaceae inside Coniferophyta. |
Fossil Wood
See also
- Toarcian turnover
- Toarcian formations
- Azilal Formation, part of the group
- Marne di Monte Serrone, Italy
- Podpeč Limestone, Slovenia
- El Pedregal Formation, Spain
- Mizur Formation, North Caucasus
- Sachrang Formation, Austria
- Posidonia Shale, Lagerstätte in Germany
- Irlbach Sandstone, Germany
- Ciechocinek Formation, Germany and Poland
- Krempachy Marl Formation, Poland and Slovakia
- Djupadal Formation, Central Skane
- Lava Formation, Lithuania
- Whitby Mudstone, England
- Fernie Formation, Alberta and British Columbia
- Whiteaves Formation, British Columbia
- Navajo Sandstone, Utah
- Los Molles Formation, Argentina
- Mawson Formation, Antarctica
- Kandreho Formation, Madagascar
- Kota Formation, India
- Cattamarra Coal Measures, Australia
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