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1.
Summary Liassic sponge mounds of the central High Atlas (Rich area, northern Morocco) have a stratigraphic range from the Lower/Upper
Sinemurian boundary interval up to the lower parts of the Lower Pliensbachian (Carixian). The base of Liassic sponge mounds
consists of a transgressive discontinuity, i.e., a condensed section of microbioclastic wackestones with firm- and hardgrounds,
ferruginous stromatolites, sponge spicules and ammonites. The top of Liassic sponge mounds is an irregular palaeorelief covered
by cherty marl-limestone rhythmites, namely hemipelagic spicular wackestones with radiolaria.
In the Rich area, section Foum Tillicht, the sponge mound succession has a total thickness of about 250 meters. Within this
succession we distinguished between three mound intervals. The lower mound interval shows only small, meter-scale sponge mounds
consisting of boundstones with lyssakine sponges, commensalicTerebella and the problematicumRadiomura. This interval forms a shallowing-upward sequence culminating in a bedded facies withTubiphytes, calcareous algae (Palaeodasycladus), sponge lithoclasts, coated grains, and thin rims of marine cement. The middle mound interval is aggradational with decametric
mounds and distinct thrombolitic textures and reefal cavities. The mound assemblage here consists of hexactinellid sponges,
lithistid demosponges, non-rigid demosponges,Radiomura, Serpula (Dorsoserpula), Terebella, encrusting bryozoa, and minor contributions by calcareous sponges, and excavating sponges (typeAka). Thrombolites are dendrolitic and may reach sizes of several tens of centimeters, similar to the maximum size of siliceous
sponges. The upper mound interval appears retrogradational and geometries change upsection from mound shapes to flat lenses
and level-bottom, biostromal sponge banks. The biotic assemblage is similar to that of the middle mound interval and there
is no difference between mound and bank communities. The demise of sponge mounds is successive from regional spread in the
Sinemurian to more localised spots in the Lower Pliensbachian. This reduction correlates with an increasing influence of pelagic
conditions.
At Foum Tillicht, sponge mounds lack any photic contribution and there is virtually no differentiation into subcommunities
between mound surface and cavity dwelling organisms. There is some evidence that the heterotrophic food web of mound communities
was sourced by oxygen minimum zone edge effects, namely microbial recycling of essential elements such as N and P. Basin geometry
suggests a waterdepth of several 100's of meters, well below the photic zone and possibly only controlled by the depth range
of the oxygen minimum zone. Palaeoceanographic conditions of well-stratified deeper water masses diminished gradually during
widespread transgression across the Sinemurian to Pliensbachian boundary culminating in the Lower Pliensbachianibex ammonite zone. 相似文献
2.
《Annales de Paléontologie》2022,108(2):102540
In the central High Atlas, the Toarcian Stage is represented by a marl and marly limestone series of variable thickness. Two sections have been studied: Amellago (500 m) and Aït Athmane (100 m). Ammonites from the two sections allowed to characterize the Polymorphum, Levisoni, Bifrons, Gradata, and Speciosum zones. The Polymorphum Zone provided, among others: Dactylioceras (Eodactylites) mirabile, D. (E.) pseudocommune, Dactylioceras (Orthodactylites) aff. crosbeyi and Neolioceratoides aff. hoffmanni; the Levisoni Zone provided a rich ammonite fauna composed of, Calliphylloceras nilssoni, Dactylioceras (Orthodactylites) cf. semiannulatum, Eleganticeras exaratum, Harpoceras falciferum, H. pseudoserpentinum, H. serpentinum, H. subplanatum, Hildaites cf. forte, H. levisoni, H. cf. serpentiniformis, H. cf. subserpentinus, H. striatus, H. wrighti, Lytoceras siemensi, Lytoceras sp., Maconiceras soloniacense, Phylloceras sp., Polyplectus pluricostatum et Polyplectus sp.; the Bifrons Zone provided Eleganticeras sp., Harpoceras subplanatum?, Hildoceras bifrons, H. lusitanicum, H. semipolitum, H. sublevisoni, Hildoceras sp., Porpoceras gr. vortex – verticosum; the Gradata Zone was characterized by Pseudocrassiceras bayani, P. frantzi, Pseudocrassiceras sp., Pseudocrassiceras sp. indet.; and the Speciosum Zone provided an Hammatoceras aff. insigne. These species have been described and illustrated for the first time for the central High Atlas. Most of them are common to several basins of the north Tethyan margin and the Subboreal Domain of NW Europe. 相似文献
3.
《Palaeoworld》2023,32(3):442-457
In the Amellago area (central High Atlas), the widely distributed Toarcian succession consists of marls and marly limestones of the Tagoudite and Agoudim formations. We here describe, for the first time, the ammonites of the Polymorphum Zone from the Tagoudite Formation, including Canavaria cf. rosenbergi Fucini, C. aff. zancleana (Fucini), Dactylioceras (Eodactylites) mirabile (Fucini), D. (E.) aff. mirabile (Fucini), D. (E.) pseudocommune Fucini, D. (E.) simplex (Fucini), D. (Orthodactylites) aff. crosbeyi (Simpson), Lytoceras gr. villae Meneghini, Neolioceratoides cf. hoffmanni (Gemmellaro) and Praepolyplectus sp. This ammonite assemblage is closely correlated with those reported from the Polymorphum Zone of several basins of the Tethyan margins and the Northwest European Subboreal Realm, indicating marine communications between the different Moroccan Jurassic basins and the central Atlantic trough. The overlying Agoudim Formation yields ammonites of the Levisoni Zone in its base and rare ammonites of the Bifrons Zone in the middle part. Four significant changes in the ammonite assemblages during the early-middle Toarcian and their probable causes are also discussed. 相似文献
4.
Summary The high-plateau of the Jbel Bou Dahar, situated in the Central and Eastern High Atlas of Morocco, represents a Lower Jurassic
carbonate platform that drowned at the beginning of the Toarcian. Three phases of platform evolution can be distinguished:
During thepre-drowning phase (upper Sinemurian— upper Pliensbachian) the platform interior facies reflects a restricted-marine lagoonal environment, protected
by scattered buildups and cemented debris at the platform margin. Upper and mid-slope are dominated by coarse-grained, poorly
sorted limestones, deposited through debris flows during sea-level lowstands. Sea-level highstand deposits occur at the toe
of slope and are formed by an alternation of fine-grained litho- and bioclastic pack- to grainstones (turbidites), marls and
mud- to wackestones (hemipelagic oozes).
A condensed section, reflecting an abrupt and fundamental environmental change along the entire platform, characterises thedrowning phase (upper Pliensbachian— lower Toarcian). Within the platform interior densely packed biosparites represent the switch to high-energy
environments, causing erosion of the former pre-drowning lagoonal sediments. These erosional products were redeposited on
the platform slope, leading to the formation of coarse-grained non-skeletal sparites and micrites. Both platform interior
and slope successions show a series of cyclic variations in sediment composition that could have been triggered by small-scale
sea-level fluctuations.
In contrast to the abrupt facies change at the pre-drowning —drowning boundary, the transition to thepost-drowning phase (lower Toarcian—Aalenian) is gradual. During this phase, biopelmicrites and pure micrites were deposited in all platform
sections, followed by the deposition of calcistiltites. The facies point to quiet-water conditions below storm-wave base and
display a uniform deep-marine sedimentation.
This analysis shows that the drowning of the Jbel Bou Dahar carbonate platform was caused by abrupt and fundamental changes
in the shallow-water realm. After exposure of the platform, these changes prevented the carbonate factory from re-establishing
itself and made it impossible for the platform to keep up with the subsequent rise in sea level. These local changes were
probably triggered by high-frequency sealevel variations in combination with regional or even worldwide changes in ocean circulation
patterns. 相似文献
5.
M. Cherkaoui A. Baali G. Larrouy A. Sevin G. Boëtsch 《International Journal of Anthropology》2005,20(3-4):199-206
This study analyses the relationship between consanguinity, fertility and child mortality in a rural population of two moroccan
High-Atlas valleys. Among this very endogamous population, we have reconstituted, by inquiries, for each family, the totality
of its reproductive life as well as the genealogic relationships that exist between the spouses on several generations. The
analysis carried out on the group of families with women who are over 40 years old (438 families) has shown that the population
was very strong related (28% of marriages are consanguineaous). A positive association between levels of fertility, infant
mortality and consanguinity was observed. 相似文献
6.
Late Triassic Tetrapod-Dominated Ichnoassemblages from the Argana Basin (Western High Atlas,Morocco)
Abdelouahed Lagnaoui Hendrik Klein Sebastian Voigt Abdelkbir Hminna Hafid Saber Jörg W. Schneider 《Ichnos》2013,20(4):238-253
Diverse tetrapod track assemblages with Scoyenia invertebrate traces were discovered in the Triassic Timezgadiouine and Bigoudine formations of the Argana Basin (Western High Atlas, Morocco). The ichnofossils occur in alluvial plain sandstones and mudstones of the Irohalène Member (T5) and Tadart Ouadou Member (T6) considered Carnian-Norian in age by vertebrate remains and palynomorphs. Tetrapod footprints are assigned to Apatopus, Atreipus-Grallator, Eubrontes isp., Parachirotherium, cf. Parachirotherium postchirotherioides, Rhynchosauroides ispp., and Synaptichnium isp. They can be referred to lepidosauromorph/ archosauromorph, basal archosaur, and dinosauromorph trackmakers. Apatopus, represented by 11 tracks of a more than 4 m long trackway, is recorded for the first time outside of North America and Europe. The assemblage concurs with the proposed Late Triassic age of the track-bearing beds by the occurrence of Apatopus, Atreipus-Grallator, and Eubrontes. If this is accepted, the stratigraphic range of Synaptichnium and Parachirotherium, hitherto known only from Early or Middle Triassic deposits, has to be extended to the Carnian-Norian. The occurrence of Eubrontes in the Irohalene Member (T5) provides further evidence for large theropods in pre-Jurassic strata. All assemblages are referred to the Scoyenia ichnofacies indicating continental environments with alternating wet and dry conditions. 相似文献
7.
B. Sabir M. Cherkaoui A. Baali O. Lemaire J. M. Dugoujon G. Boëtsch 《International Journal of Anthropology》2005,20(3-4):277-289
With an aim of characterising the genetic structure of the Berber population, of the Western High Atlas (Marrakesh), and of
locating it compared to the other known populations, a preliminary study of the digital dermatoglyphes relating to a sample
of 100 individuals (50 men and 50 women) non related taken at random in the population of the commune of Asni (Wilaya de Marrakesh)
was carried out. The frequencies of the digital figures obtained in this population are respectively 50.2% of the ulnar loops,
40.6% of the whorls, 7.7% of the archs and 1.5% of the radial loops. No significant difference between the two sexes has been
observed. Compared with other Moroccan populations, while basing, oneself on the relatively frequency of the arch, one raises
more resemblance of our population (9.2% among women and 6.2% among the men) to the Arab population of the region of Doukkala
(8.85% at the men and 7.2% among women) that with the Berber population of the Middle Atlas (5.26% at the men and 5.63% among
women). Compared with other Mediterranean populations, the Berber of the High-Atlas remain among the populations which present
a higher arch percentage. The analysis of affinities of the digital figures between the population object, of the study and
those of the Mediterranean by the Euclidean distances show that this one presents characteristics which differentiates, it
from the other populations. One can not however, that conversely with other Moroccan populations analysed, the one becomes
attached more to the group, of populations of south of the Mediterranean (Arab and Berber) than to the group of the north
populations of mediterranean area (Spain, France and Italy). 相似文献
8.
Body size of orthoconic cephalopods from the late Silurian and Devonian of the Anti‐Atlas (Morocco) 下载免费PDF全文
Alexander Pohle Christian Klug 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2018,51(1):126-148
Fluctuations in body size of orthoconic cephalopods are reported from late Silurian to Late Devonian sediments at several locations in the Tafilalt and in the Dra‐Valley (Anti‐Atlas, Morocco). The combination of measurements of diameters and apical angles allows the reconstruction of their total conch size (length and volume), which revealed a strongly right‐skewed size distribution with an average length of 278 mm, while the largest Devonian actinocerids exceeded 2 m. Within the examined groups (Actinocerida, Orthocerida, Pseudorthocerida), there is no uniform trend, but rather frequent fluctuations with maximum sizes in the late Lochkovian and early Emsian. Body size decreased in times of extinction events, while stable periods are mostly associated with a size increase. Additionally, conch size correlates well with gamma diversity and global δ13C values. Furthermore, the apical angle and septal diameter of orthocones appear to correlate, but only when their mean values are compared across beds. 相似文献
9.
The Morava river forms a border 71 km in length between Slovakia and Austria. Along this stretch of river is the largest complex of flooded grasslands in Central Europe, most of which lays on the Slovak side. Most of the grasslands belong to the subcontinental vegetation alliance Cnidion, with smaller areas of Alopecurion and Molinion. The grasslands are biotopes of many endangered plant and animal species. The influence of water regime dynamics on species composition have been studied since 1992 along permanent transects. The results of studies on the relation between water regime dynamics, vegetation and soils on the whole section of the Morava River floodplain are presented. 相似文献
10.
11.
Two new species of the Empis (Leptempis) rustica group are described: E. (L.) tenuis n. sp. and E. (L.) lauriauti n. sp. Both were mainly collected in mountainous areas of the Mediterranean basin; the first species was collected in Morocco and Southern Spain; the latter was found in late summer in the Southern Alps in France. The key to species of the Empis (L.) rustica group is updated to include these two new species as well as a recently described Caucasian species. 相似文献
12.
Whereas Middle Jurassic gastropods are very well known in Europe and other regions of the world, these faunas have been much less studied from northern Africa and most contributions available in literature have been based on relatively well-preserved material. Except a little lower Bajocian fauna from the Central High Atlas (Morocco) described at the turn of the 21th century, nothing is known about the Middle Jurassic gastropods of the southwestern Tethyan margin. The present paper aims to update the systematics of two vetigastropod species: Obornella cf. granulata (Sowerby, 1818) and Ambercyclus ornatus (Sowerby, 1819) recently found in the upper Bajocian succession of the Ksour Mountains (Tniet el Klakh Formation) at western Saharan Atlas (northern Algeria). The new Ambercyclus material found in well-preserved conditions confirms the absence of umbilicus in Ambercyclus; thus, we emend the original generic diagnosis. The specimens of Obornella cf. granulata and Ambercyclus ornatus represent the first occurrence of both genera and species in the upper Bajocian marine deposits of the western Saharan Atlas, and provide new taxonomic and palaeobiogeographic information about Middle Jurassic vetigastropods in Algeria. 相似文献
13.
Magdalena Ralska-Jasiewiczowa Ewa Madeyska Marta Mierzeńska 《Vegetation History and Archaeobotany》2006,15(4):391-401
The pollen analytical investigations of hanging peat bogs in the summit zone of the Polish east Carpathians show that the absence of the upper montane spruce zone in the western Bieszczady mountains is a phenomenon that has been historically stable at least for the last millennium and probably also in earlier times. At altitudes corresponding to the spruce zone in other parts of the Carpathians, dwarf beech woods form here a low-lying upper tree limit. The montane grassland zone occurring above this tree line did not result from human activities, although it has been extended by human activity. Besides, it is shown how far it is possible to reconstruct from a pollen diagram the differentiation of vegetation surrounding the site of profile collection located in the upper montane zone when the present-day local plant communities are well known, in spite of pollen from long distance transport always being present at the summits of mountain ranges. 相似文献
14.
Battal Çiplak 《Biodiversity and Conservation》2003,12(1):47-64
The distribution of Tettigoniinae (Orthoptera, Tettigoniidae) specieswithin four phytogeographical provinces in Turkey is reviewed and presented onthe basis of field and collection studies during 1987–2001 andmiscellaneous data from previous literature. One hundred and sixty speciesbelonging to 28 genera have been recorded. The Anatolian species constituteapproximately 30% of the world-wide species of the subfamily, with a very highproportion (83%) being endemic or semi-endemic, nearly all of which arebrachypterous. Regarding the numbers of total and endemic species, theprovinces can be ordered as follows: Mediterranean > Irano-Anatolian >Euxin > Mesopotamia. Also, Anatolian Tettigoniinae have a very high rate ofendemism in each province; 84.1% in the Mediterranean, 78.1% in Irano-Anatolia,56.3% in Mesopotamia and 42.4% in Euxin. The two provinces in Anatolia havingthe greatest species diversity are also the two most mountainous provinces, soit is suggested that a primary factor in Tettigoniinae diversity is theAnatolian Taurus mountains. Finally, some conclusions are drawn on biodiversityand conservation of Tettigoniinae species in Anatolia and I have suggested 23species to be included in the 'IUCN Red List' under VU B2+ac. 相似文献
15.
《Annales de Paléontologie》2017,103(3):185-196
In the southwestern part of Algeria, the Cenomanian-Turonian marine deposits build up a prominent ledge in a perched syncline (Ksour Mountains, western Saharan Atlas) or at high radius of curvature (Guir Basin). The petrographical analysis of the Cenomanian-Turonian deposits of the Ksour Mountains and of the Guir Basin reveals unexpected assemblages of roveacrinoidal ossicles comparable with those formerly reported from the Tinrhert area. For the first time, isolated ossicles of genuine and undisputable Roveacrinidae are illustrated. Three sections, Djebel Rhoundjaia (western Saharan Atlas), Berridel and Kénadsa (Guir Basin), were scrutinized to recognize the microcrinoidal sections within the carbonate microfacies and to compile the successive occurrence of respective roveacrinid taxa (besides the classical search for standard index microfossils) in an attempt to pinpoint more precisely the position of the Cenomanian-Turonian boundary (C/T B). These assemblages are particularly morphologically and taxonomically diverse with three species of genus Roveacrinus and one of genus Orthogonocrinus. The presence of Saccocomidae (Applinocrinus) is especially unusual in such stratigraphic levels. The relative abundance and diversity of Roveacrinidae evidence a peak when approaching the C/T B. Such an event is recurring in the latest Cenomanian in various Tethyan and Atlantic areas. These fluctuations are consistent with a high surface-water productivity just before the C/T B. 相似文献
16.
17.
The paper presents the results of investigations concerning the accumulation processes, sediment composition, pollen and macroscopic analyses of sediments from the lakes Popradské pleso (1513 m) and Štrbské pleso (1345 m) in the High Tatra mountains, western Carpathians, Slovakia. While Popradské pleso is undoubtedly of glacial origin with silts in the Lateglacial layers and algal gyttja in the Holocene layers, Štrbské pleso or its greater part originated recently between the 16th and the beginning of the 18th centuries when the previous bog of Atlantic or early Subboreal age was flooded with water after the dispersed outflow from the bog depression was blocked. Our pollen and macrofossil analyses indicate mountain tundra in the Lateglacial and a continuous presence of coniferous forest with Picea abies with admixture of Pinus cembra, Larix decidua, Juniperus communis and Pinus cf. mugo in the uppermost elevations at the alpine forest limit since the very beginning of the Holocene. No noticeable oscillation of the forest line can be interpreted from our pollen analyses. It seems probable that its position was controlled by geomorphological and edaphic conditions rather than by the Holocene climatic changes. Spruce forests dominated at elevations between ca. 1000–1400 m during the whole Holocene. 相似文献
18.
19.
Bernadette Montanari 《植物分类与资源学报》2014,36(3):388-402
This article compliments the S18 session (transmission of traditional ecological knowledge and conservation of medicinal plants) at the 13th International Congress of Ethnobiology (ISE) in Montpellier, France (May 2012). The aim of the article is to provide an insight into the livelihoods of a Berber community, a village of the High Atlas Mountains of Morocco, of the local biodiversity and most importantly, the prevalent use of medicinal plants for primary health care. It seeks to demonstrate the value of traditional ecological and herbal knowledge for the subsistence of the community and emphasises the vital role that family and community connections play for the transmission of traditional herbal knowledge within the community. 相似文献
20.
Bernadette Montanari 《Plant Diversity》2014,36(3):388-402
This article compliments the S18 session (transmission of traditional ecological knowledge and conservation of medicinal plants) at the 13th International Congress of Ethnobiology (ISE) in Montpellier, France (May 2012). The aim of the article is to provide an insight into the livelihoods of a Berber community, a village of the High Atlas Mountains of Morocco, of the local biodiversity and most importantly, the prevalent use of medicinal plants for primary health care. It seeks to demonstrate the value of traditional ecological and herbal knowledge for the subsistence of the community and emphasises the vital role that family and community connections play for the transmission of traditional herbal knowledge within the community. 相似文献