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1.
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   

2.
A 122 cm-long core was taken in the El-Guettiate Sebkha of Skhira (southeastern part of Tunisia) in order to investigate the recent palaeoenvironmental evolution of this region. The quantitative and qualitative analysis of ostracod and benthic foraminifera assemblages coupled with a correspondence analysis allows the reconstruction of palaeoenvironmental changes during the Holocene in this area. Four typical associations of ostracods (open marine, coastal marine, lagoonal and estuarine brackish) and two associations of benthic foraminifera (coastal and lagoonal) were distinguished. The onset of restricted lagoonal environments linked to the building-up of sand spit led to the onset of restricted lagoon and brackish environment at cal. 5408 years BP. The Shannon and equitability index of diversity were used to decipher the structural variations of the populations of ostracods and benthic foraminifera along the sampled core. We note a reduction in the Shannon index from the bottom to the top, which indicates a progressive isolation of the biotope. The open lagoonal episode is characterized by high values of diversity. During restricted lagoonal episodes the Shannon and equitability index are reduced. The correspondence analysis reveals an environmental gradient related to the marine influence. It shows an antagonism between the widely opened estuarian lagoonal species and those of restricted lagoon. The less opened estuarian lagoonal taxa occupy an intermediate position. Based on these evidences, microfauna carried out in the El-Guettiate Sebkha allows us to recognize four phases beginning with a widely opened estuarian lagoon (ca. cal. 7460 years PB), followed by a restricted lagoon (ca. cal. 5408 years BP) and finally a brackish lagoon evolving towards the present-day sebkha environment. The opened estuarine lagoon is characterized by high values of species richness and diversity indices.  相似文献   

3.
The Upper Pleistocene and the Holocene of Aigion have delivered an abundant microfauna with 35 ostracode species. The Pleistocene from Aigion borehole generally provides Ostracodes from oligohaline environment with Cyprideis torosa, Candona angulata and Tyrrhenocythere amnicola while, in the Holocene, marine infralittoral species dominate with Cytheridea neapolitana, Carinocythereis whitei, Loxoconcha ovulata and Cytherois frequens. The marine sedimentation occurred at depth from some meters to some tens of meters. In the Aghios Constantinos section, the lagoonal marls are characterised by Euxinocythere schuldtae and a dwarf species of Xestoleberis. Then, a drastic environmental change occurs around the Pleistocene-Holocene boundary and presumably affected the whole Corinth gulf.  相似文献   

4.
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   

5.
The Solen 98 well corresponds to the limestones of the Lower Tithonian Cazals Formation (Gigas Zone). The iterative succession of six sedimentary terms expresses a cyclic peritidal dynamic. Limited by two emersion surfaces, each sequence evolves from an upper subtidal lagoon to a tidal flat, upper intertidal or supratidal environment, and ends with open sea depositional bioclastic and oolitic shoals deposits. Hierarchical ascendant classification applied to palynological data define 6 palynofacies types associated with different depositional facies. Type 1, characterizing open marine deposits, shows a diversified and balanced assemblage. The blade-shape woody particles are abundant and the amorphous organic matter is absent. Types 2 and 3 are linked to lagoonal and skeletal shoals deposits. Then microfossil population is dominated by Corculodinium or long-spine Micrhystridium. The Shannon-Weaver and the equitability indices are moderate. Type 4 is associated with the upper tidal flat, lagoonal and skeletal shoal deposits. When microfossils are present, the algal assemblages are more balanced than in type 5. This type, observed in all the palaeo-environments except the open marine, is enriched in elements attributed to the Hyalinsphaeridia complex. The marine component assemblages are balanced. The amorphous organic matter is relatively abundant and the oxydized woody particles absent. Type 6, mainly composed of amorphous organic matter and phytoclasts, is principally associated with the stromatolitic facies of tidal flat deposits. The example of the Solen 98 well, shows that hierarchical ascendant classification method is well suited for identification of palynofacies  相似文献   

6.
In several synclines of the central High Atlas, the “Redbeds” following the closure of the marine Tethyan Atlasic trough during the Middle Jurassic are constituted by three successive formations or units of continental deposits dated recently with biostratigraphical elements. Some micropaleontological markers, mainly charophytes and ostracods, allow to precise the stratigraphy in agreement with a Bathonian-?Callovian assignment for the lower unit (Guettioua Formation), and in dating the middle and upper units. The Upper Jurassic, mainly the Kimmeridgian, is developed in the lower part of the middle unit (Iouaridene Formation). The Barremian has been recognized in this middle unit and in the upper unit (Jbel Sidal Formation). The Jurassic/Cretaceous boundary is thus delimited for the first time with micropaleontological data. These new data are very significant for the Atlasic history during the Mesozoic. The basaltic flows inserted in the continental Jurassic-Cretaceous deposits of the central High Atlas result from two separate events in the Middle Jurassic and in the Barremian. The tectogenesis in the basins is characterized by a polyphase process including notably a synsedimentary tectonic activity conspicuous in the Barremian. The evidence of marine to brackish intercalations allows moreover to date the first Cretaceous transgressive event on the NW boundary of the High Atlas during the Lower Barremian and to consider an Atlantic paleogeographical interaction. SW margin of the Tethyan trough in the Lower and Middle Jurassic, the central High Atlas is merged with the margin of the central Atlantic Ocean during the Lower Cretaceous.  相似文献   

7.
The amber of Le Mas d’Azil (Ariège, France), fashioned by the Magdalenian people of Le Mas d’Azil cave, was collected in clay levels rich in Cupressinoxylon Göppert, of the Campanian Labarre Sandstone Formation, which is a large deltaic set, infilling the sub-Pyreneean trough. The amber pieces are small and resemble modern resin exudates on coniferous trunks. We describe following micro-inclusions. Actinomycetes: Cardonia stellata, nov. gen., nov. sp., located close to the surface of amber pieces, is abundant and displays chains of conidia and isolated aleuriospore. Nocardiopsis ? sp. D is rare. Actinomycete “de type Salignac” is abundant. Its filaments often display a tendril shape, which seems to prelude to a mycelium fragmentation. Other bacteria: Leptotrichites resinatus Schmidt ( Schmidt and Schäfer, 2005), poorly represented, is more variable than the already known material; cf. Sphaerotilus sp., very abundant, also displays differences with the Cenomanian “Sphaerotilus sp.”. Eukaryotes: one fungal filament, and a group of spores, pollens or cysts. Inorganic inclusions: gas bubbles, pseudo-protists of B and C? types, and tiny, transparent, cubic crystals. It seems that most of the quoted prokaryotes were resinicolous organisms, able to settle on the surface of the exudate, and grow in the resin, after inoculation either by a contact with the substrate, or by an anemophilic dispersion of spores. This “taphonomic way” seems here to be more general than trapping.  相似文献   

8.
A biozonation based on Lituolids, Orbitolinids and Dasycladacean algae is given. Although most of the fossils used are typical of lagoonal environments, the proposed biozonation has been tested using Ammonits, Calpionellids and planktonic Forams. The present biozonation is in agreement with the ones described from other Mediterranean realms.  相似文献   

9.
The site of Pirro Nord (also known as Cava Pirro or Cava Dell’Erba) is known in literature since the 1970's of the last century as a palaeontological site, of which the mammalian fossil association constitutes a reference (local) fauna for the European latest Villafranchian. This fossil association is also known for the occurrence of some African elements. During the 2005, a lithic industry has been found in three karst fissures, together with the typical elements of the Pirro Nord vertebrate assemblage. The biochronological assessment based on the vertebrate assemblage attributes it to a time interval bracketed between 1.3 Ma and 1.7 Ma. Thus the site of Pirro Nord represents the oldest human occupation of Europe so far known. The lithic assemblage, attributable to the Mode 1, is constituted by three cores and seven flakes, and is made only on flint. Lithic artefacts have been found in stratigraphic context during the preliminary surveys of the three fissures, that they will be the object of systematic excavations in the years to come.  相似文献   

10.
The lithic industry discovered at the Dmanissi site, in Georgia is dated to between 1.81 and 1.7 Myrs and is in association with a rich faunal assemblage composed of large Quaternary vertebrates, as well as several hominid fossils attributed to Homo georgicus, and attests to the human presence on the border of Europe at the beginning of the Lower Pleistocene. The material taken into account in this study was excavated from 1991 to 1999 and comprises 4446 lithic pieces coming from Beds I through VI of the site. The assemblage is very homogenous from the base to the top of the deposits and shows no significative evolutionary tendencies. The lithic material includes a high proportion of whole pebbles (33.8% of the assemblage) coming from two nearby rivers, the Mashavera and the Pinezaouri. They are essentially of fine and coarse grained volcanic tuff, basalt, but also of rhyolite, granite, quartz, as well as other volcanic and metamorphic rocks. Pebbles used for percussion, shaping or debitage were chosen according to their petrographic nature, their morphology and their size. Whole pebbles with percussion marks situated on their extremities or with isolated removals showing convexe edges, are abundant (1.3% of the assemblage). Other pebbles showing percussion marks on a flat face, were used as anvils. Broken pebbles and pebble fragments are very numerous (30.4% of the assemblage). These often show percussion marks on their cortical surfaces. Fractures are generally related to violent percussion as the pebbles were used for striking instruments, or as they were intentionally broken. Some fractures may have been caused accidentally during flaking. Pebble tools represent 4.8% of the lithic assemblage and 10% of the industry, excluding whole and fractured pebbles. These include essentially the primary choppers (pebbles with isolated concave removal negatives) (6% of the industry and 60.1% of the pebble tools), choppers showing continuous cutting edges without a point (2.1% of the industry and 21.2% of the pebble tools). Chopping-tools are very rare (0.8% of the industry and 8.7% of the pebble tools). Although choppers without pointed cutting edges were made using very few removals (3.3 on average), they usually present a regular cutting edge and seem relatively standardised. Cores are well represented (5% of the industry, excluding whole and broken pebbles). They are characterized by a low degree of exploitation and by a frequence of cortical striking platforms. Cored knapped on a single face are most frequent, representing nearly half of the pieces (42.3%), while bifacial cores are present in smaller proportions (34.2%) and multifacial cores are rare (6.3%). Non-modified flakes are very numerous and usually of small size and intentional retouch is absent. On the other hand, the cuttingedges of many the pieces; broken pebbles, pebble tools, cores and flakes, show irregular micro-retouch and irregular retouch such as isolated notches or with continuous or overlapping configuration, sometimes associated with localised crush marks which appear to have been caused by intensive use and heavy working of the pieces. A total of 31.3% of the non-modified flakes show irregular retouch on their cutting edges. One of the main characteristics of the Dmanissi industry appears therefore to be the obtaining of flakes, most often of small size, to be used without modification. The technological and typological characteristics of the lithic industry from Dmanissi allow to attribute the assemblage to a "Pre-Oldowayen" cultural horizon (Lumley de et al., 2004), characterized by the absence of small retouched tools, which appears in East Africa from 2.55 Myrs ago. This cultural horizon is present at the border of Europe, at Dmanissi, around 1.81 Myrs ago and in Western Europe, on the shores of the Mediterranean, at Barranco León about 1.3 Myrs ago and at Fuente Nueva 3 about 1.2 Myrs ago. The lithic industry from the Dmanissi site seems anterior to the Oldowan cultural horizon, characterized by the presence of standardized small retouched tools, which appears in East Africa around 1.8 Myrs ago and emerges in Mediterranean Europe around 800?000 years ago.  相似文献   

11.
The objective of this paper is to present the anthracological data of the Parco cave sequence. This cave, excavated since the last 25 years, shows a stratigraphic sequence from the Upper Palaeolithic to the Bronze age. The anthracological data that we are presenting correspond to the sequence corresponding to the Magdalenian and Epipaleolithic layers. The anthracological data show a dominance of Scots pine at the bottom and of junipers at the top of the deposit, suggesting a landscape transformation though time. From these results we discuss aspects related to the vegetal formations during this period. Moreover, this study has the intention of integration the anthracological record with the archaeological data already published concerning subsistence, technology and paleoecology to a better understanding to human behaviour during this period.  相似文献   

12.
This work is mainly an answer to the work of Bert (2009), on families Helicancylidae Hyatt, 1894 and Acrioceratidae Vermeulen, 2009. On the nomenclatural speaking, the non validity of the genus Helicancylus Gabb, 1869 and of the family Helicancylidae Hyatt, 1894 and, consequently, the validity of the family Acrioceratidae Vermeulen, 2004 are established. The second part of this work is devoted to the respect of former work and, contrary to the assertions from Bert (2009), it is shown that the stratigraphical positioning of the Upper Barremian level with small Barremites, realized by Cotillon (1971), is at least as precise as that proposed by Bert. The last part of this work highlights a lack of bibliographical references, fact which had already been highlighted ( Vermeulen and Lepinay, 2010) in a former work of Bert et al. (2009).  相似文献   

13.
Gyrogonites of charophytes from two localities of the Oudiksou syncline (Middle Atlas, Morocco) are studied. The Irbzer formation in the Achlouj-2 site yielded charophytes (Feistiella oblonga, F. globosa, Strobilochara apiculata, S. diademata) that suggest a Campanian-Maastrichtian age; this result is consistent with all previously published biochronological studies. The overlying Bekrit-Timahdit formation, supposed to be Thanetian to Lutetian in age, without paleontological evidence, yielded charophytes in the Saf locality (Peckichara cf. llobregatensis, Feistiella sp. 1, Maedleriella sp.). This association indicates a Paleocene age for the middle member of this formation.  相似文献   

14.
A non-site approach permits the analysis of settlement patterns of mesolithic groups in the Ourthe Basin (Belgium) in terms of “behavioural tendencies”. These tendencies allow a hypothesis of dynamic behaviour to be proposed, in relation to its ethnological significance. This approach, applied to the question of neolithisation, demonstrates the active role that played the mesolithic substrate in this process.  相似文献   

15.
Biometric study of the inner features of Heterostegina specimens preserved in tortonian sediments of the oued Yhoudi member allows to confirm the presence of species Heterostegina papyracea Seguenza, 1880. Analysis of both large and small components of the foraminiferal assemblage in all examined samples establishes the dominant character of species Heterostegina papyracea Seguenza (more than 60% of total benthic foraminifera). The assemblage of small benthic foraminifera associated with the Heterostegina is different from that described from Recent sediments, as well as from Miocene sediments of Calabria and Spain. In order to explain this result, two hypotheses can be put forward: (1) the Tortonian Heterostegina from Morocco proliferated abundantly in very shallow environments in association with small foraminifera (i.e. abundant Ammonia beccarii). (2) Because of powerful tidal currents in the South Rifian Corridor, Heterostegina tests were probably transferred after death. This transfer could possibly be due to the narrowness of the South Rifian Corridor in the Early Late Tortonian and its position between the Atlantic and the Mediterranean. Similar cases foraminiferal displacements are also known from modern basins. This study illustrates the difficulties in reconstructing the paleogeography of the studied area and the importance of considering all available components of the assemblage.  相似文献   

16.
Pollen analysis of Madonna dell’Arma cave inside part (Liguria, Italy) allowed us to reconstitute, at local scale, the Ligurian coastal vegetation between the end of the last interglacial period and the beginning of the pleniglacial. This transition period shows an important representation of arboreal cover and a persistence of thermophilous elements that allowed us to considerate the western Liguria as a periglacial refuge. During the end of the last interglacial, xerophytic, halophytic herbs and shrubs taken over from a Mediterranean pre-forest unit in the first slopes constituted the coastal zone. The nearness of Argentina torrent and the Armea influenced, in the coast, the existence of marshy zones colonized by hygrophilous trees. In the Ligurian lowlands spread out sclerophyllous and mesophilous forests according to altitude. The beginning of the pleniglacial is indicated in the sequence by increases of Pinus, Cupressaceae and Artemisia in the context of a decline in the thermophilous components. This picture of vegetation has become integrated into the multidisciplinary studies of the site and contributed to the elaboration of palaeoclimatic hypothesis similar as those revealed by the fauna.  相似文献   

17.
The position of lithic industries of Chinese Paleolithic in comparison with those of other regions in the world is always a controversial topic. The typological analysis has made Chinese prehistorians reveal some variability between lithic industries of different regions of China in terms of technical tradition and industrial structure. But this recognition, based upon some morphological characters of stone artifacts, failed to define systematically the modes of production that exist in each site. To answer these problematic some new methods need to be applied. So the lithic materials from 8 Chinese sites dated from 300 ka to 50 ka B.P. were selected and analyzed by means of lithic technological analysis and a new approach for analyzing the structures of cores. This paper presents principally the analytical results of modes of débitage and revealed that the modes of débitage during this period were characterized essentially by system C (“simple débitage”) and E (discoid) and that the concept Levallois was absent during this period in technical systems of lithic production in China. The Chinese lithic industries between 300 ka and 50 ka B.P. saw some homogeneity in the scale of the continent and remarkable difference from those of other regions in the world. So a stable, continuous but independent even isolated evolution in comparison with those of other regions was observed in this period. In addition, despite of apparent homogeneity, some variability exists also between these industries.  相似文献   

18.
An archaeological diagnostic at Falaise revealed a pile of 6 stone rings, isolated from any domestic or burial features. The isolation suggests that the find can be interpreted as a ritual hoard. This hypothesis is possibly confirmed by other aspects: the alternating sizes and raw materials, as well as the site location between two dense early Neolithic settlement zones. The finds probably date to the late Villeneuve-Saint-Germain/Blicquy. The flat, wide rings have traces of manufacture and use. Analysis indicates that they were worn as arm ornaments, at the minimum in pairs. The raw materials, very common in assemblages from north-western France, are of regional origin. Comparable finds in France are rare, limiting interpretation of the hoard. This practice is not frequent and usually involves ring roughouts or worn grindstones, although these technical constraints do not rule out a certain ritualisation. At Falaise, the latter is perceptible but the objects are neither rare nor unusual. For this reason, the phenomenon differs from hoards of axe blades in Danubian cultures of the Rhineland, or of prestige axes at the beginning of the middle Neolithic.  相似文献   

19.
The open-air site of Collet-Redon (Martigues, Bouches-du-Rhône) was discovered in the 1940s, and excavated by M. Escalon de Fonton until the beginning of 1980s. Those pioneering works gave up important series of artefacts and domestic structures of Late Neolithic and Bronze Age that permit to define a new Neolithic culture: the Couronnien group. The importance of this establishment, as a reference in research on Late Neolithic period in South of France, is particularly based on built remains revealed in a sector called “Habitation no. 1”. Quantity and quality of architectural structures allowed M. Escalon de Fonton to describe a Neolithic domestic unit, which became a model for interpreting other regional sites. Since 1999, various studies of artefacts and structures, coupled with an excavation, have been engaged in order to discuss first interpretations. The purpose of this article is to present our results concerning architectural remains of “Habitation no. 1” sector. Study of ancient publications and new observations on structures permit us to suggest a revision of the plan proposed for this third millenary construction.  相似文献   

20.
The El Harhoura 2 cave is situated in the commune of El Harhoura in the Temara region (Morocco). The entrance faces west, towards the ocean, around 200 m away from the current shoreline and about 16 m above sea level. The stratigraphy has currently 11 levels numbered from top to bottom. Level 1 is attributed to the early Neolithic. The archaeological material from level 2 places it within the Upper Palaeolithic (Iberomaurusian). Levels 3 to 11 are assigned to the Middle Palaeolithic (Aterian). Since 1977, a surface of 37 m2 has been excavated, yielding particularly abundant remains of a large mammal fauna study in this paper.  相似文献   

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