Azay-le-Rideau, France
Azay-le-Rideau, France

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Benzaggagh M.,Moulay Ismaï University | Latil J.-L.,Le Maupas | Oumhamed M.,Moulay Ismaï University | Ferre B.,Dame du Lac 213
Cretaceous Research | Year: 2017

Lithostratigraphical analysis of more than ten sections of the El Mizab Formation (Talerhza Basin), previously assigned to the “Vraconnian” lead to distinguish a similar succession of five members, called from oldest to youngest: Silty marly limestones; Lower shelly marly limestones, Platy limestones, Upper shelly marly limestones and Marly limestones with Rhynchostreon. The lower and middle parts of the second member yielded a rich ammonite fauna of Mortoniceras (Mortoniceras) pricei and Mortoniceras (M.) inflatum zones, including: Hypengonoceras faugeresi sp. nov., Mortoniceras (Deiradoceras) aff. albense Spath, Mortoniceras (D.) bipunctatum Spath, Mortoniceras (D.) cunningtoni Spath, Mortoniceras (Mortoniceras) pricei (Spath), Mortoniceras (M.) inflatum (Sowerby) and Oxytropidoceras (Tarfayites) cf. bituberculatum Collignon. The upper part of the same member and the lower part of the fourth one yielded rare Mortoniceras (M.) fallax (Breistoffer) and Mortoniceras (M.) pachys (Seeley) of the Mortoniceras (M.) fallax Zone. The first member, having not yielded any ammonites, may have an early late Albian age, probably within the Dipoloceras cristatum Zone? The fifth member, rich in Rhynchostreon suborbiculatum (Lamarck), could be early? Cenomanian in age. The two underlying formations, El Heitouf and Bab Lkarma, previously assigned to the upper Albian (Mortoniceras inflatum Zone), could have an early to middle Albian age. The collected ammonites are studied and illustrated in the present contribution. © 2017 Elsevier Ltd


Benzaggagh M.,Moulay Ismaï University | Oumhamed M.,Moulay Ismaï University | Ferre B.,Dame du Lac 213 | Latil J.-L.,Le Maupas
Cretaceous Research | Year: 2017

The Wadi Daya Formation, or the Calcaires crayeux of the older literature, attains a thickness of 10–40 m in the Talerhza Basin of the South Riffian Ridges. Previously, this unit was first dated as “Vraconian” (i.e., late upper Albian), but then reinterpreted as Cenomanian-Turonian and Cenomanian-Coniacian on the basis of foraminiferal and ostracod assemblages, respectively. Here, we record for the first time in the South Riffian Ridges, some typically Turonian ammonoids and a nautiloid species, namely Romaniceras (Yubariceras) cf. ornatissimum (Stoliczka), Spathites (Jeanrogericeras) cf. reveliereanus (Courtiller), Neoptychites cephalotus (Courtiller), Pachydesmoceras linderi (de Grossouvre), Lewesiceras peramplum (Mantell) and Angulithes galea (Fritsch, in Fritsch & Schlönbach). These species are herein described and illustrated. In view of these data, the underlying Marnes et marno-calcaires jaunes Formation, formerly dated as “Vraconian”, could in fact be of a middle to late Cenomanian date, in accordance with the age assignment based on planktonic foraminifera. Deposition of the overlying Marnes jaunes Formation, previously dated as Cenomanian-“Senonian”, probably started during the latest Turonian or earliest Coniacian. © 2017 Elsevier Ltd


Chihaoui A.,Joseph Fourier University | Jaillard E.,IRD Montpellier | Latil J.-L.,Le Maupas | Zghal I.,University of Sfax | And 3 more authors.
Journal of African Earth Sciences | Year: 2010

In the Tadjerouine area of north-western central Tunisia, the Albian transgression is characterized by deposition of alternating marls, limestones and sandstones (Hameima Fm) that overly massive platform carbonate rocks (Serdj Fm). The continuing transgression results in deposition of a thick series of marls and shales with subordinate carbonate beds (Fahdene Fm). A detailed study of the Hameima Fm, previously ascribed to the Late Aptian, shows that this formation can be subdivided into three members, all of earliest Albian age (Leymeriella tardefurcata Zone). The top of the Hameima Fm is slightly diachronous in the study area. A similar study of the Lower Shales of the Fahdene Fm demonstrates that they belong to the L. tardefurcata Zone and to the lower part of the Douvilleiceras mammillatum superzone. The overlying Allam limestones, formerly considered Middle Albian in age, are mainly of late Early Albian age (upper part of the D. mammillatum Superzone and Lyelliceras pseudolyelli Zone), although an extension into the lower Middle Albian cannot be ruled out. The Allam limestones are abruptly overlain by a diachronous series of Late Albian shales (Middle Shales of the Fahdene Fm), thus evidencing a stratigraphic hiatus of most of the Middle Albian and part of the early Late Albian. Our new data will lead to revision of the range of some Aptian/Albian orbitolinids and Albian planktic foraminifera. © 2010 Elsevier Ltd.


Hfaiedh R.,University of Sfax | Arnaud Vanneau A.,Association Dolomieu | Godet A.,Association Dolomieu | Godet A.,University of Lausanne | And 6 more authors.
Cretaceous Research | Year: 2013

The Aptian sedimentary succession of the Chott region in southern Tunisia was deposited on the margin of the Saharan shield, and is punctuated by numerous hiatuses that separate seven 3rd-order depositional sequences. Early Aptian deposits correspond to the Berrani Member (early Bedoulian), which was deposited contemporaneously with the large carbonate platforms with rudists that developed under oligo-mesotrophic, tropical environmental conditions on both margins of the Tethys. Late Bedoulian sediments were deposited under mesotrophic conditions characterized by seagrass, algae, abundant orbitolinids and aragonite-producing organisms. The early to late Aptian transition was marked by the temporary disappearance of carbonate platforms and an important renewal of the microfauna, whose tests and skeletons became less and less aragonite-rich and more and more calcite-rich and arenaceous. This episode is reported from both Tethyan margins. The platform was subsequently flooded, and dysoxic environments with annelids marked the end of the early Aptian carbonate platform development. An arid and probably colder episode (earliest late Aptian) induced the deposition of gypsum in an intrashelf basin. Following on top, the return to more humid conditions triggered an enhanced input of detrital material in fluvio-deltaic environments (late Aptian). Finally, the return to oligo-mesotrophic, marine conditions allowed the temporary installation of wide lagoons with rudists in the latest Aptian and probably in the earliest Albian. Long-distance correlations have been established by means of benthic foraminiferal occurrences. They highlight the importance of stratigraphic gaps linked to low sea levels, which have been tentatively estimated.© 2013 Elsevier Ltd.


Reboulet S.,University Claude Bernard Lyon 1 | Rawson P.F.,University of Hull | Rawson P.F.,University College London | Moreno-Bedmar J.A.,National Autonomous University of Mexico | And 20 more authors.
Cretaceous Research | Year: 2011

The 4th Kilian Group meeting (Dijon, France, 30th August 2010) focused on the Aptian and Albian Stages. For the Aptian, a two-fold division of the stage was adopted for the Mediterranean area with a boundary between the Dufrenoyia furcata and Epicheloniceras martini Zones. The main changes to the zonal scheme concern the Lower Aptian with: the introduction of a Deshayesites luppovi Subzone in the upper part of the Deshayesites oglanlensis Zone; the replacement of Deshayesites weissi by Deshayesites forbesi as new index-species of the second interval zone; the introduction of a Roloboceras hambrovi Subzone in the upper part of the D. forbesi Zone; and the subdivision of the D. furcata Zone into the D. furcata and Dufrenoyia dufrenoyi Subzones. For the Albian, the upper part of the Douvilleiceras mammillatum Zone (Lower Albian) is now characterized by a Lyelliceras pseudolyelli Subzone. The main amendments concern the Upper Albian. The base of this substage is defined by the base of the Dipoloceras cristatum Zone. Above it, the Upper Albian zonal scheme comprises in stratigraphic order the Mortoniceras pricei, Mortoniceras inflatum, Mortoniceras fallax, Mortoniceras rostratum, Mortoniceras perinflatum and Arrhaphoceras briacensis Zones. © 2011 Elsevier Ltd.


Garcia R.,Av. Josep Tarradelles i Joan 14 bxs. 4 | Moreno-Bedmar J.A.,National Autonomous University of Mexico | Bover-Arnal T.,University of Granada | Company M.,University of Barcelona | And 8 more authors.
Journal of Iberian Geology | Year: 2014

A review of the stratigraphic distribution of ammonoid species in the Lower Cretaceous (Hauterivian-Albian) of the Maestrat Basin (E Spain) was carried out. The specimens were mainly collected in the field by us and are stored in university or museum collections. Specimens from private collections and figured in the literature were also studied. We recognized 73 species that are distributed, in accordance with the latest version of the standard Mediterranean ammonite zonation for the Lower Cretaceous, in 14 ammonite zones: Acanthodiscus radiatus, Crioceratites loryi, Lyticoceras nodosoplicatum (Lower Hauterivian); Pseudothurmannia ohmi (Upper Hauterivian); Imerites giraudi (Upper Barremian); Deshayesites oglanlensis, Deshayesites forbesi, Deshayesites deshayesi, Dufrenoyia furcata (Lower Aptian); Epicheloniceras martini, Parahoplites melchioris, Acanthohoplites nolani (Upper Aptian); Leymeriella tardefurcata and Douvilleiceras mammillatum (Lower Albian). The recognition of these biozones allows a precise age calibration of the Maestrat Basin's lithostatigraphic units that contain ammonoids as well as an associated indirect age calibration of the formations without ammonoids. Consequently, this report provides an updated, comprehensive and precise biostratigraphic framework, which aims to become a reference for the analysis of the Lower Cretaceous strata of the Maestrat Basin. The results are also relevant for the analysis of coeval ammonite-bearing sedimentary successions found in other Tethyan basins.


Moreno-Bedmar J.A.,National Autonomous University of Mexico | Latil J.-L.,Le Maupas | Villanueva-Amadoz U.,National Autonomous University of Mexico | Calvillo-Canadell L.,National Autonomous University of Mexico | Cevallos-Ferriz S.R.S.,National Autonomous University of Mexico
Journal of South American Earth Sciences | Year: 2014

This paper dates the El Chango Lagerstätte (Chiapas, SE Mexico), known for its exceptionally well-preserved marine fishes, plant remains, crustaceans, insects and mollusks, based on ammonite biostratigraphy. The age of the El Chango fauna is imprecisely assigned to either the late Albian or Cenomanian. We document here an ammonite assemblage comprising Graysonites and ?Metengonoceras. Graysonites, which gives a lowermost early Cenomanian age, Cintalapa Formation pro parte. We noticed that the terminology of lithostratigraphic units in the studied area is confusing and varies considerably depending on the author, therefore proposing the use of Cintalapa Formation for the El Chango section and the Sierra Madre as a group that includes it. © 2014 Elsevier Ltd.


The taxonomic treatment of the Engonoceratoidea Hyatt, 1900 (Wright et al., 1996) is problematic and confusing, and recently has gained the attention of many paleontologists (Robert, 2002; Bujtor, 2010; Bulot, 2010; Latil, 2011). It appears that most of the described genera within this superfamily were based on morphological features, without stratigraphic and/or phylogenetic control. In particular, the genus Platiknemiceras Bataller, 1954, seems to represent a classic example of this problem. Knemiceras gracile Douvillé, 1916, from the Early Albian of Maghara area, north Sinai, Egypt, referred by Casey (1961) to Platiknemiceras, appears to be an often misinterpreted species. Species identified as members of the genus Platiknemiceras Bataller, 1954 in the literature, from Iran, Lebanon, Egypt, Tunisia, Algeria, Spain, France Peru, Colombia, Venezuela, USA and Japan are discussed herein, in order to revise their taxonomic positions. The type species, Platiknemiceras bassei Bataller 1954, is redescribed. A re-examination of the relationships between Knemiceras gracile and other members of the genus Platiknemiceras strongly suggests that this latter genus is polyphyletic.


Latil J.-L.,Le Maupas
Revue de Paleobiologie | Year: 2011

Nine sections were measured and studied in the Tadjerouine area (Central Tunisia), providing an abundant paleontological material. The historical collections of Pervinquière (1907) from Central Tunisia, Dubourdieu (Dubourdieu, 1949, 1953 and 1956 ; Breistroffer, 1953a ; Sornay, 1955) and Masse (Masse & Thieuloy, 1979) for the Ouenza area (Algeria) are revised and integrated to the paleontological and biostratigraphical study. A new regional biozonation on the basis of the ammonites is proposed for the Early Albian of Central Tunisia, revealing an almost complete and continuous succession from the base of the Albian to its top. Unfortunately, due to the lack of paleontological datas, the Aptian-Albian boundary cannot be defined. The ammonite succession allows precise correlations with the ammonite biozonation established in western Europe (Owen, 1999, 2002 ; Kennedy et al., 2000). The Hameima section (HMA) in Jebel Hameima, is herein considered as a regional reference which is completed by the Harraba section (HB) in Jebel Harraba for the lower part and Bou El Haneche section (BEH) in Jebel Bou El Haneche for the upper part. This biostratigraphical sequence is the most complete for the Early Albian of the South tethyan margins. An Earliest Albian detailed ammonite succession is recognized for the first time on the South Tethyan Margins. Three new ammonite genera are herein described : Hameimaceras gen. nov., Buloticeras gen. nov. and Mellegueiceras nov. gen. Nine species are new : Hameimaceras zghalae gen. nov., sp. nov. ; Pseudhelicoceras dubourdieui sp. nov. ; Douvilleiceras sp. nov. ? ; Mellegueiceras chihaouiae nov. gen., nov. sp. ; Mellegueiceras hameimaensis nov. gen., nov. sp. ; Mellegueiceras minutus nov. gen., nov. sp. ; Mellegueiceras jaillardi nov. gen., nov.sp. ; 'Hypacanthoplites' roberti sp. nov. and 'Hypacanthoplites' buloti sp. nov. These species all come from the earliest part of the Early Albian, revealing a high level of ammonite endemism on the central Tunisian platform. This endemism strongly declines with the Early Albian transgression.


Bulot L.G.,Aix - Marseille University | Latil J.-L.,Le Maupas | Hairabian A.,Aix - Marseille University | Fournillon A.,Aix - Marseille University
Proceedings of the Geologists' Association | Year: 2014

Nolaniceras nolani (Seunes, 1887) has been widely quoted in the Upper Aptian literature over the years. Re-examination of the holotype of the species shows that it has always been misidentified and that this taxon is represented by a single specimen, the holotype, of uncertain age. As a consequence, its use as an index species for the Upper Aptian should be reconsidered and abandoned. © 2014 The Geologists' Association.

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