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1.
The originality of the sedimentary deposits and ammonite faunas in the jebel Bou Rharraf concerns “Ammonitico Rosso” facies, the westernmost known for the Pliensbachian, and a strong diversity of the Phylloceratida (Phylloceras, Calaiceras, Zetoceras, Partschiceras and Juraphyllites). The morphological disparity is also important in Galaticeras, Miltoceras and Tauromeniceras. If some taxa like Miltoceras taguendoufi and Mauretaniaceras elmii nov. gen., nov. sp. seem endemic to the High Atlas, most part of the Pliensbachien ammonites of the eastern High Atlas are classic for the southern margin of the western Tethys. Three genera (Callomoniceras, Appenninoceras, Mauretaniaceras) and three new species (Miltoceras involutum, Tropidoceras heterogeneum, Mauretaniaceras elmii) are described. An analysis using the “Discrete Cosine Transform” (DCT) method allows the better understanding of the morphospace of the rib patterns for the Fuciniceras from jebel Bou Rharraf. The biostratigraphy of the High Atlas is also improved with a set of 19 biohorizons for the Pliensbachian and the base of the Toarcian that are correlable with the Tethyan areas.  相似文献   

2.
The Liassic ammonite faunas and especially those of the Early Pliensbachian are of major importance for the understanding of the stratigraphic framework of the “Dauphiné” zone of the southern subalpine ranges (“dôme de Remollon”). Until now, only listed by the authors, these faunas are, for the first time, described and illustrated in the present paper. With about twenty species, these faunas cover the whole of the Early Pliensbachian. There are poorly diversified and of clearly Euroboreal affinities. Nearly all of the species are abundant and common in most of the NW European fossiliferous localities. Despite of a paleogeographical location fairly close to the Alpine zones (Southern Alps and Austroalpine units) with rather diversified faunas of mainly Mediterranean affinities, none Mediterranean taxa are present in the studied area. Unfortunately, the current stratigraphic and paleogeographic knowledge do not allow to ascertain if this reflects a separation due to paleoenvironmental or true paleogeographic barriers. In this latter case, the general geologic implications would be remarkable.  相似文献   

3.
J Thierry 《Geobios》2003,36(1):93-126
The ammonite fauna of the outcropping Bathonian-Callovian of the Boulonnais (Northern France) is described in detail for the first time. In the middle and Late Bathonian, the fauna is very restricted, reduced to some Perisphinctidae (Procerites) and Clydoniceratidae (Clydoniceras, Delecticeras). The abundance and the biodiversity of assemblages increase during the Callovian. These faunas are typically Subboreal, marked by Gowericeratinae (Kepplerites, Sigaloceras), Kosmoceratinae (Kosmoceras) and Proplanulitinae (Proplanulites), associated with Boreal taxa such as Cadoceratinae (Cadoceras) and Cardioceratidae (Quenstedtoceras), and Submediterranean taxa, Pseudoperisphinctinae (Homoeoplanulites, Poculisphinctes), Peltoceratinae (Pseudopeltoceras) and Macrocephalitinae (Macrocephalites). Representing the only Jurassic onshore outcrops, between the English and Normandy coasts, and the Ardennes area, the interest of these faunas for correlations between the Western and Eastern European (Russian) platforms is emphasized. Palaeobiogeographically, particularly concerning the southward migration/dispersion of the Boreal taxa, the role played by the transgressions/regressions and the resulting paleobathymetric and palaeoclimatic implications is discussed.  相似文献   

4.
The carbonate sediments of the Agadir Basin (Morocco) deposited during the Upper Bathonian-Lower Kimmeridgian p.p. interval are rich in agglutinated complex benthic foraminifera. The detailed inventory of several field-sections allows to identify and to describe these benthonic foraminifera, some of them being recorded for the first time in Morocco. They belong to the main genera Archaeosepta, Andersenolina, Praekurnubia, Pseudocyclammina, Everticyclammina, Alveosepta, Kurnubia, Parurgonina, Neokilianina, Labyrinthina and Rectocyclammina. The stratigraphic and paleobiogeographic distribution of these foraminifera seem to be related to the geodynamic events occurring on the Moroccan Atlantic margin during this time-interval. The stratigraphic distribution of the principal species is generally controlled by the occurrence of ammonites, brachiopods and of some foraminifera which are considered as good stratigraphic markers.  相似文献   

5.
Ostracode assemblages, collected in the continental “Red Beds” of the Central High Atlas, Morocco, consist of 35 species, belonging to 17 genera, four of which are new and described herein. They allow to assign the lower member of the Iouaridène formation to the Upper Jurassic (?)-Upper Hauterivian and the Jbel Sidal formation to the Upper Hauterivian-Lower Aptian. Ostracode assemblages characterize lacustrine (freshwater) and lagoonal (oligo to mesohaline) environments. On the basis of limnic and lagoonal species, faunal connections are proposed for the Barremian-Aptian between Morocco and the Iberian Peninsula.  相似文献   

6.
Acheulean sites are located in almost every areas of Georgia. Most of the time, in Western Georgia, there are few bifaces; these are more common in Eastern Georgia (except in the basins of the Iori and Alazani rivers). In general, the Acheulean of the Southern Caucasus looses rapidly the bifacial shapes and develops into the Typical Mousterian, the Levalloisian and the Charentian.  相似文献   

7.
Recent researches carried out in the uppert part of the “Calcare Massiccio” formation of Monte Cucco allowed to recover a rich Sinemurian fauna of gastropods, bivalves, brachiopods, ammonoids and some solitary corals. The gastropod fauna is greatly dominant and includes 18 species which belong to the superfamilies Pleurotomarioidea, Fissurelloidea, Amberleyoidea, Neritoidea, Loxonematoidea, Cerithioidea, Nerineoidea, Littorinoidea and Acteonoidea. Ten species of gastropods are here described for the first time. This fauna shows a marked affinity with that of the Sinemurian of Sicily. Under a paleoecological point of view, it is indicative of free marine conditions, in photic zone but under a weak hydrodynamism, and therefore may suggests the reference to a deep infralittoral or upper circalittoral environment.  相似文献   

8.
    
A microfauna composed of 11 species of ostracodes belonging to 11 genera have been recovered from the Bhanness Formation of Kimmeridgian age, in Central Lebanon. Four species are new and are described herein: Ektyphocythere dahressawanensis nov. sp., Dicrorygma (Orthorygma) libanensis nov. sp., Citrella? elongata nov. sp. and Procytherura inflata nov. sp. From a palaeobiogeographical standpoint, this fauna characterizes the North Gondwana province which differs from the South Gondwana province, particularly by the presence of the genus Schuleridea and the absence of the genus Majungaella.  相似文献   

9.
In Tunisia, in the platform domain, the Aptian-Albian transition is associated with a major stratigraphic gap not precisely dated, which is related to the subaerial exposure of the Aptian Orbata platform. Locally, in central Tunisia (Jebel Kebar), this gap is substituted by the sedimentary records of the Kebar Formation. This formation provided a rich association of fossil charophytes, formed by Atopochara trivolvis trivolvis, Clavator harrisii zavialensis and Sphaerochara verticillata which allows attributing it to the late Aptian–early Albian interval (most probably early Albian). In addition, a new variety, Sphaerochara verticillata var. kebariensis, is described. The charophyte assemblage shows significant biogeographic affinities with a coeval flora found in the Iberian Peninsula. The Kebar Formation was previously regarded as exclusively nonmarine, but the presence of the assemblage of charophytes and associated ostracods described rather indicates a fluctuation between margino-littoral (lagoonal) and continental environments.  相似文献   

10.
The discovery in the uppermost Jurassic of Lebanon of a species of the ostracod genus Microceratina Swanson, 1980 (Eucytherurinae), of which the oldest known species was until now of Maastrichtian age, confirms the Tethyan origin of this genus. Two new species are created: Microceratina bhannesensis nov. sp. from the Upper Jurassic (Kimmeridgian) of Lebanon, and Microceratina azazoulensis nov. sp. from the Cenomanian of Morocco. The genera Chapmanicytherura Weaver, 1982 and Erratacytheridea Herrig et al., 1997, are considered as probable junior synonyms of Microceratina. An exhaustive bibliographical analysis allowed to identifying several other Cretaceous species susceptible to be assigned to the genus Microceratina.  相似文献   

11.
The Candona clivosa-group, a new group of Candoninae - is erected on the base of the folded inner lamella observed on the postero-ventral border of the female valve. The elongated sub-triangular and rectangular valves of this group are described from the Miocene and Quaternary deposits of Europe. A folded inner lamella is also observed in 11 species of Candona from the Upper Miocene of the Turiec Basin of which 8 are new - Candona fatrica nov. sp., C. tatrica nov. sp., C. lacustris nov. sp., C. palustris nov. sp., C. stagnosa nov. sp., C. laterisimilis nov. sp., C. jiriceki nov. sp. and C. incurva nov. sp. They show a higher variability of the outline, calcification of the valves and width of the zone of concrescence. The extrinsic and intrinsic aspects of this morphological diversification in the Turiec Basin are discussed.  相似文献   

12.
Thirty-four species of ostracodes are collected in the platform series of the Southern Corbières; two biostratigraphical assemblages, with 13 and 29 species, are respectively recognized in Cenomanian and Upper Turonian; palaeoecology is specified. At that time, the ostracode sub-province of South-West France, established on Southern Corbières, Aquitaine, Touraine-Poitou-Charentes region and Provence, is connected with Eastern and Northern regions and countries: Sub-alpines ranges, Paris Basin, Great Britain, Switzerland and Bohemia, and with the Iberian Peninsula, sub-province of North-Central Spain and Western Portuguese Basin. The crossing of the Tethys and the Atlantic Ocean is realized, in Turonian, by some rare species.  相似文献   

13.
    
An association of limnic ostracodes has been discovered in the upper part of the Irbzer Formation, of Maastrichtian age, in the Moroccan Middle-Atlas. A new species is described, Gomphocythere achloujensis nov. sp. Paracandona occitanica, which is very common in terminal Cretaceous non-marine deposits of southern Europe (France, Spain), is found for the first time on the south Tethyan margin.  相似文献   

14.
These stone tools from Yunxian with other Lower Paleolithic sites in South China, for example, the site Lantian (Shanxi, China) and the site Bose (Guangxi, China), indicates that there are many common characteristics among these industries. There are choppers, chopping-tools, picks, hand-axes, cleavers and scrapers. Long ago we thought that there are not hand-axes in China. In fact, there are lots of hand-axes in China and these hand-axes existed more earlier than those in Europe. The hand-axe appeared in China before 800,000 years old and it barely arrived in Europe before 600,000 years old. The quaternary deposits of the site of Yunxian Hominid (Hubei, China) are at least dated to 800,000 years old. A large quantity of lower Paleolithic material was discovered. The types of the tools are choppers, picks, scrapers, hand-axes and cleavers. The pebbles tools make up the majority of the implements. Small flake tools are relatively rare. The lithic industries comparison of the two regions has help us to know the cultural evolution in China and Europe.  相似文献   

15.
A new ammonite (Fuciniceras paradoxus) is described here. This Lower Domerian species is based on a recently revised collections which came from the Maria Pares section (Rabaçal area, South of Coimbra, Portugal). Curiously, shell of F. paradoxus bears both diagnostic traits for the genus Protogrammoceras SPATH (e.g. acute ogival ventral area) and Fuciniceras HAAS (e.g. angulirursiradiate rib). Thus, the new species can be viewed as a morphological puzzle and as a challenge for taxonomists. The amazing collection of morphological traits previously suspected as highly improbable because of biomechanical constraints (1) confirms the inadequacy of the traditional use of the genera Protogrammoceras and Fuciniceras, (2) refutes the idea of a univocal biomechanic link between the ventral area morphology and the ventral segment of ribs. If this analysis mainly concern the Harpoceratinae subfamily, its generalisation can also be interesting for other ammonites or molluscan groups.  相似文献   

16.
The recent biostratigraphic and micropaleontologic works permitted to specify the distribution of Megaporellaboulangeri Deloffre and Beun in the Jurassic of the Moroccan Atlantic basin. The lower limit of the extension of this dasycladale alga, earlier attribued to the Early Kimmeridgian by Deloffre and Beun (1986), is currently placed in the Early Callovian, on the basis of the age provided by Megaporellaboulangeri biozone. The Otternstellaarabica biozone dates the upper limit of the extension of the species of the Early Oxfordian. Megaporellaboulangeri proliferates in the borders of the basin where the internal lagoons facies dominate, however it is absent in the western parts with open sea facies.  相似文献   

17.
Bizat Ruhama is a lower Palaeolithic site in the southern coastal plain of Israel. The site was recently dated to ca. 1ma. In terms of lithic industry, Bizat Ruhama is a unique phenomenon amongst the Lower Palaeolithic sites in the Levant. The lithic assemblage of the site is characterized by the production of small (ca. 25mm) tools, flakes and cores. An in-depth technotypological study was made in attempt to reconstruct the production mode of these artifacts. The results presented here reveal a well-developed cognitive production process, which includes selection of special-sized raw material, production of desired blanks and their subsequent shaping into tools. The implications of this study contribute significantly to our understanding of the phenomenon of lower Palaeolithic microlithic industries in Eurasia.  相似文献   

18.
During the Upper Paleolithic, Europe was occupied by human populations mainly living from hunting of big terrestrial mammals. A repartition of fauna and of archeological sites was done with a database: a repartition of Upper Paleolithic sites in central and western Europe. This study shows that the european space was structured following several factors; climate, environment, cynegetic behaviours… We observe a partition of Europe with a mediterranean area with mainly deer, and ibex and an atlantic area with reindeer. Equally, most of the occupations are localized in the “aquitano-cantabric horn” around the Gulf of Gascony. The occupation of Europe undergone a pulsation with a retreat of occupations toward the west and the south during the glacial maximum, then a colonization of North Europe during the Tardiglacial climatic amelioration.  相似文献   

19.
A new and yet unpublished palaeontological revision of very important collections accomplished these last thirty years in many localities of Morocco and Western Algeria joined to the already published data, allow us to propose a biostratigraphical succession of the Middle Jurassic Brachiopods suitable to the Southern Margin of the Western Tethys. This Brachiopod scale is correlated with the standard chronostratigraphy based on ammonites. It involves eight zones and six sub-zones separated by five interval zones where Brachiopods are missing. Moreover, brachiopods have not been discovered in Early Aalenian and Late Callovian. Afterwards, the two brachiopod zonations established on the northern and southern margins of the Western Tethys are compared. On a paleontological plane, a new definition of the species Burmirhynchiaathiensis warrants to precise its vertical distribution (Parkinsoni and Zigzag zones) and to give a better distinction with Burmirhynchiatermierae (Humphriesianum and Niortense zones).  相似文献   

20.
Recent researches on the Lower Jurassic of Western Algeria allow to establish a lithostratigraphic standard correlating the different members and formations developed in the Ouarsenis and Tlemcen Mountains, the Oran High Plains, the Nador and Ksour Mountains. The position of the large bivalve limestones (= Lithiotis limestones) is well established in the different lithologic successions. This facies is widespread in Western Algeria where it is interbedded with brachiopod marker beds, indicating short periods of maximum flooding. The large number of collected brachiopods are distributed into four “faunas” (assemblages) ranging from the Late Sinemurian (= Lotharingian) to the Early Pliensbachian (= Carixian). These faunas have been dated by the age of the species that they have in common with the NW european and western tethyan provinces. These chronological data are confirmed by rare ammonites. All these results evidence the age of the large bivalve facies in Western Algeria. They are contained in the Middle to Late Carixian (Demonense and Dilectum Zones). This datation is in conformity with that known from the Eastern High-Atlas (Bou Dahar). Consequently, the large bivalves cannot be considered as “markers for the unique Domerian” as it has been too often asserted. The palaeontological part of our study shows that the multicostate Zeilleriids (several Tauromenia species from the Late Sinemurian to the Early Carixian) are older than the multicostate Terebratulids (Hesperithyris species from the Middle to Late Carixian).  相似文献   

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