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1.
Seven bryozoan species belonging to the Order Rhabdomesida and Order Cystoporida are described from the Permian deposits exposed near the small town of Deh-e Mohammad, Shotori Mountains (northeastern Iran): Rhabdomeson cf. consimile Bassler, Pamirella nitida Gorjunova, Clausotrypa conferta Bassler, Streblotrypa (Streblotrypa) elegans Sakagami, Streblotrypa (Streblascopora) supernodata nov. sp., Cystodictya sp., and Filiramoporina cf. kretaphilia Fry and Cuffey. The described fauna identifies the age of the Jamal Formation at the locality near Deh-e Mohammad as Lower Permian. It displays palaeobiogeographic connections to the Lower Permian of Pamir (Tajikistan), Indonesia, Thailand and Kansas (North America).  相似文献   

2.
Summary The upper part of the LowerPseudoschwagerina Limestone (Rattendorf Group), outcropping on the northwestern flank of Schulterkofel Mountain, Carnic Alps (Austria) is described with special emphasis on fusulinid microfossils and facies. This fusulinid-rich section offers an ideal opportunity for biostratigraphy in defining the Permo-Carboniferous boundary in this region. The LowerPseudoschwagerina Limestone is composed of shallow-marine limestones with intercalated thin siltstone and sandstone beds. Fusulinid limestones are represented by two types of wackestones, both containing large quantities of smaller foraminifers. Fusulinid grainstones are rare. Limestones rich in fusulinids were found only within the bedded limestone facies in beds both below and especially above siliciclastic intercalations. This may indicate that the best living conditions for fusulinids existed immediately before and especially after the climax of a regressive phase (sea-level lowstand). The fusulinid limestones were deposited within a protected, shallow-marine shelf environment with normal salinity. Pseudoschwagerinid fusulinids appear in the upper part of the LowerPseudoschwagerina Limestone, in samples SK 107d (undeterminable species) and SK 108, i.e. between 92 m and 93 m above the base of the section within a bedded limestone immediately above the uppermost clastic intercalation. The fusulinid fauna is represented by about 30 species belonging to only a few genera. Species ofTriticites andRugosofusulina dominate, whereas those ofDaixina, Rugosochusenella andPseudofusulina are rare. A characteristic feature of the fauna is the strong similarity with fusulinid faunas described from Russia as well as from Middle and East Asia. Some of the described fusulinids are new for the Carnic Alps. The first appearance ofPseudoschwagerina andOccidentoschwagerina (Occidentoschwagerina alpina Zone) in the upper part of the LowerPseudoschwagerina Limestone in the Schulterkofel section defines the position of the Carboniferous-Permian boundary.  相似文献   

3.
Dr. Karl Krainer 《Facies》1995,33(1):195-214
Summary A heretofore undocumented example of skeletal mounds formed by the dasycladacean algaAnthracoporella spectabilis is described from mixed carbonate-clastic cycles (Auernig cyclothems) of the Late Carboniferous (Gzhelian) Auernig Group of the central Carnic Alps in southern Austria. The massive mound facies forms biostromal reef mounds that are up to several m thick and extend laterally over more than 100 m. The mound facies is developed in the middle of bedded limestones, which are up to 16 m thick. These limestones formed during relative sea-level highstands when clastic influx was near zero. The mound facies is characterized by well developed baffler and binder guilds and does not show any horizontal or vertical zonation. Within the massive mound faciesAnthracoporella is frequently found in growth position forming bafflestones and wackestones composed of abundantAnthracoporella skeletons which toppled in situ or drifted slightly.Anthracoporella grew in such profusion that it dominated the available sea bottom living space, forming ‘algal meadows’ which acted as efficient sediment producers and bafflers. BecauseAnthracoporella could not provide a substantial reef framework, and could not withstand high water turbulence, the biostromal skeletal mounds accumulated in shallow, quiet water below the active wave base in water depths less than 30 m. The massive mound facies is under- and overlain by, and laterally grades into bedded, fossiliferous limestones of the intermound facies, composed mainly of different types of wackestones and packstones. Individual beds containAnthracoporella andArchaeolithophyllum missouriense in growth position, forming “micromounds’. Two stages of mound formation are recognized: (1) the stabilization stage when bioclastic wackestones accumulated, and (2) the skeletal mound stage when the sea-bottom was colonized byAnthracoporella and other members of the baffler and binder guilds, formingAnthracoporella bafflestones and wackestones of the mound facies. A slight drop in sea-level led to the termination of the mound growth and accumulation of organic debris, particularly calcareous algae, fusulinids, crinoids and bryozoans, forming well bedded limestones, which overlie the mound facies  相似文献   

4.
Gerd Rantitsch 《Facies》2007,53(1):129-140
The Gartnerkofel-1 core provides a high-quality multi-element dataset that characterizes an Upper Permian to Lower Triassic shallow-marine carbonate sequence (Bellerophon and Werfen Formations) of the Carnic Alps (Southern Alps). Based on the well-known sedimentological evolution, robust sequential Factor Analysis is explored as a multivariate statistical technique to understand geochemical processes in carbonate platforms. The results demonstrate that 93% of the whole-rock compositional variability of the Gartnerkofel-1 core can be explained by the detrital input that is diluted by the carbonate production and the early diagenetic redox state. Two stages of anoxia, one at the Permian/Triassic boundary and one in the Mazzin Member of the Werfen Formation, are related to indicative factor scores. The factor scores within this interval suggest an enhanced dolomitization of shales and marls, a mobilization of manganese, and an accumulation of syndiagenetically precipitated pyrite.  相似文献   

5.
The bryozoan fauna from the Xiazhen Formation (Katian, Upper Ordovician) of northeast Jiangxi Province, southeast China is reported here. Seventeen species of bryozoans belonging to fifteen genera and four orders are identified: Homotrypa yushanensis, Homotrypa sp., Prasopora yushanensis, Trematopora sp., Monotrypella sp., Rhombotrypa sp., Orbignyella sp., Constellaria jiangxiensis, Constellaria sp., Stictopora nicholsoni, Trigonodictya parvula, Ptilodictya ensiformis, Stictoporella sp., Pseudopachydictya sp., Nematopora sp., Arthrostylidae sp. indet., and Chasmatoporidae sp. indet. Four of these genera have been reported previously but nine genera (Trematopora, Monotrypella, Rhombotrypa, Orbignyella, Trigonodictya, Ptilodictya, Stictoporella, Pseudopachydictya, and Nematopora), one rhabdomesine and one fenestrate are found for the first time in the Late Ordovician strata of South China. Our palaeogeographical analysis suggests that the bryozoan association is typical for the Katian, which is mostly widespread in Laurentia, Siberia, Baltica and Mediterranean, and displays palaeobiogeographical relationships to the Laurentia–Siberia Province.  相似文献   

6.
Summary Diverse and abundant trace fossils of the deep-waterNereites ichnofacies have been found in well-dated Early Permian deep-water turbidites (Lercara Formation) of western Sicily (Italy). Conodonts indicate a latest Artinskian to Cathedralian (late Early Permian) age. Microfossils (pelagic conodonts, albaillellid Radiolaria, paleopsychrospheric ostracods, foraminiferal associations dominated byBathysiphon), trace fossils (deep-bathyal to abyssalNereites ichnofacies) and sedimentologic data collectively indicate a deep-water environment for the Early Permian turbidites of the Lercara Formation. The dominance ofAgrichnium and of thePaleodictyon subichnogeneraSquamodictyon andMegadictyon suggests that this icnofauna is closely related in ichnotaxonomic composition to other late Paleozoic deep-water ichnofaunas. The occurrence ofAcanthorhaphe. Dendrotichnium andHelicoraphe, to date only reported from Cretaceous or Tertiary flysch deposits, suggests that the entire ichnofauna corresponds well to previously documented Silurian-Tertiary flysch ichnofaunas. Eight new ichnospecies and a new ichnosubgenus,Megadictyon, are described.  相似文献   

7.
Twenty species belonging to fifteen genera of cyclostome and cheilostome bryozoans encrusting belemnite rostra are described from the late Campanian to Maastrichtian of the Aktolagay Plateau, in western Kazakhstan. Due to the moderate to poor preservation of the material, only four cheilostome species are identified down to the species level: Wilbertopora? besoktiensis (Voigt, 1967), ‘Aechmellinastenostoma Voigt, 1930, and two new species, ‘Aechmellinaviskovae and Cheethamia aktolagayensis. All remaining species are left in open nomenclature. Type material of Wilbertopora? besoktiensis from the early Maastrichtian of the Mangyshlak Peninsula in Kazakhstan, has been re-examined. Palaeobiogeographical and implications are discussed. Cheilostomes slightly dominated over cyclostomes in the Aktolagay Plateau fauna encrusting on belemnites in terms of diversity. The dominant colony forms observed were spots and sheets.  相似文献   

8.
This paper reviews the archaeobotanical research conducted on the plant material recovered from the Iceman′s body, his garment and equipment, as well as that from the sediments of the gully in which the body was discovered more than 15 years ago. These recent results are discussed against the background of the archaeological findings during the last few years and disclose both conformities and discrepancies of the disciplinary-centred views. In particular the archaeobotanical results concerning the season of death as well as the taphonomic interpretation of the find assemblage give cause for controversial discussions and constitute the future research focus. Furthermore, the singularity of this discovery demands an evaluation of the archaeobotanical findings within a circum-alpine context to reveal the representativeness of this find assemblage for the inner alpine Neolithic. This was the objective of a specific symposium at the 17th International Botanical Congress in Vienna in 2005.  相似文献   

9.
10.
Early Permian crinoids and blastoids from Oman show relationship with Late Paleozoic Tethyan faunas of Timor and Western Australia and support an Early Permian age for part of the Basleo fauna of Timor. The camerate crinoidPlatycrinites omanensis n. sp. and the blastoidsTimoroblastus andDeltoblastus are reported for the first time from Sakmarian strata of northeastern Oman, doubling the known Permian echinoderms from Oman. The blastoids suggest an offshore lower energy shelf environment of deposition.   相似文献   

11.
Forke  Holger C. 《Facies》2002,47(1):201-275
Summary In order to establish a refined biostratigraphic subdivision and correlation of the Uppermost Carboniferous/Lower Permian deposits of the Southern Alps (Carnic Alps, Karavanke Mountains; Austria/Italy/Slovenia), two major microfossil groups (fusulinoideans, conodonts) were investigated within the same sample. The fusulinoidean species diversity (71 species, including five new species and three new subspecies) and generic composition were reviewed and complemented. Additionally, the data on fusulinoidean assemblages were supplemented by co-occurring conodont faunas (seven species). Accompanying studies on material from the type sections of the Southern Urals (Russia) were made to improve the biostratigraphic correlation with the Russian standard zonation and to discuss paleobiogeographical aspects of the faunal associations. An integrated microfacies analysis of the sampled material in the Southern Alps serves to evaluate the relationships between certain genera and specific microfacies types. The fusulinoidean fauna of the Lower “Pseudoschwagerina” Limestone is of late Gzhelian age. The Carboniferous/Permian boundary is close to the base of the Grenzland Formation, which covers the entire Asselian and a part of the Sakmarian. The Upper “Pseudoschwagerina” Limestone and Trogkofel Limestone are Lake Sakmarian to Artinskian. The studies sequences in the Karavanke Mountains. formerly known as “carbonate and clastic Trogkofel beds”, correlate to the Lower “Pseudoschwagerina” Limestone, respectively with parts of the Grenzland Formation. Due to the lithologic differences, new formation names (Dolzanova Soteska Fm., Born Fm.) were introduced for the so-called “Trogkofel” Limestone along the Dolzanova Soteska. Whereas late Gzhelian/Asselian fusulinoidean faunas of the Southern Alps correspond to the Southern Uralian faunas to a large extent, Sakmarian and Artinskian faunas reveal an increasing divergence in species and genus composition. Climatic as well as geographic barriers may have prevennted the dispersal of Paleotethyan taxa into the Southern Urals. Biostratigraphic correlation of Sakmarian to Artinskian deposits is therefore possible only on the basis of the sparse conodont faunas.  相似文献   

12.
New species of Transcaucasian bryozoans are described: Primorela remota and Pseudoascopora subtilis (order Rhabdomesida) from the Upper Famennian and Anisotrypa hamata (order Trepostomida), Paranicklesopora stupenda, Euthyrhombopora barbara, Primorella testata, Ipmorella clara (order Rhabdomesida), and Taeniodictya vermiculata (order Cryptostomida) from the Tournaisian.  相似文献   

13.
Summary During the uppermost Carboniferous and lowermost Permian algal mounds were formed in inner shelf settings of the Carnic Alps (Austria/Italy). A specific mound type, characterized by the dominance of the dasyclad green alga Anthracoporella was studied in detail with regard to geometry, relationship between mound and intermound rocks, composition of the sediment, biota and diagenetic criteria. The two meter-sized mounds studied, occur within depositional sequences of transgressive systems tracts in the Lower Pseudoschwagerina Limestones (uppermost Gzhelian) at the flank of the Schulterkofel. The mounds consist of an Anthracoporella core facies with a spongecrust boundstone facies at the base and at the top. The massive limestones of the Anthracoporella core facies exhibit abundant algal tufts and bushes, frequently in life position. The limestones of the intermound facies represented by thin-bedded bioclastic wackestones and packstones with abundant phylloid algae underlie and overlie the mounds. Intercalations of intermound beds within the mound facies indicate sporadic disruption of mound growth. Onlapping of intermound beds on steep mound flanks indicate rapid stabilization and lithification of mound flanks and the existence of a positive paleorelief. Asymmetrical shape of the mounds may be current controlled. Mound and intermound biota differ in the prevailing algae but are relatively similar with regard to associated foraminifera. Conspicuous differences concern bioerosion and biogenic encrustations. Bothare, high in intermound areas but low in the Anthracoporella core facies. The mounds show no ecological zonation. The mounds grew by in-place accumulation of disintegrated algal material and trapped bioclastic material between erect algal thalli. The comparison of the various Anthracoporella mounds demonstrates that almost each mound had ist own history. Establishing a general model for these mounds is a hazardous venture.  相似文献   

14.
Summary The Bombaso Formation and basal Meledis Formation in the central Carnic Alps near Straniger Alm and Zollnersee (Austria/Italy) unconformably overlie the folded Variscan basement and consist of shallow marine clastic and carbonate sediments which are arranged to form two fining and deepening upward sequences. Particularly limestones and even breccias of the Bombaso Formation yielded a rich fusulinid fauna composed of 34 species which are attributed to the following zones:Quasifusulinoides quasifusulinoides-Protriticites ovatus; Protriticites pseudomontiparus, andMontiparus montiparus. Breccias of the Bombaso Formation west of Straniger Alm contain the oldest fusulinid fauna of the Carnic Alps, belonging to theQuasifusulinoides quasifusulinoides —Protriticites ovatus zone. The fauna is composed ofQuasifusulinoides quasifusulinoides, Q. fallax, Q. intermedius, Protriticites cf.ovoides, andPr. ovatus. This assemblage is most similar to that of the Peskovskaya Formation of the Myachkovian Horizon in the Moscow Basin indicating uppermost Moscovian age. Limestones from depositional sequence 1 at Zollnersee also contain fusulinids of the uppermost Moscovian which are characterized by a more diverse assemblage:Schubertella donetzica, Fusiella lancetiformis, Beedeina ulitinensis, B. consobrina, B. nytvica, B. siviniensis, Quasifusulinoides pakhrensis, Q. fallax, Q. kljasmicus, Q. quasifusulinoides, Fusulinella rara, andProtriticites ovatus. Limestones and calcareous sandstones-siltstones of the basal Meledis Formation of depositional sequence 2 near Zollnersee and at Cima Val di Puartis are characterized by fusulinids of theProtriticites pseudomontiparus zone (Protriticites globulus, Pr. pseudomontiparus, Pr. sphaericus, Pr. rotundatus, Pr. ovoides, Pr. lamellosus, andPraeobsoletes burkemensis) and byMontiparus paramontiparus zone (Praeobsoletes pauper, P. burkemensis, Obsoletes timanicus, O. obsoletes, Montiparus paramontiparus, M. umbonoplicatus, M. montiparus, M. likharevi, M. rhombiformis andM. priscus) indicating lower to middle Kasimovian age (Krevyakinskian and Khamovnicheskian Horizons of the Russian Platform). In memoriam FranzKahler (1900–1995)  相似文献   

15.
In order to maintain branch strength and a confluent outer membrane, trepostome bryozoans had to maintain a continuous colony surface without any structural gaps. This put great constructional demands on colonies with relatively thick exozones to fill the exozonal space while preserving a suitable autozooecial spacing for colony-wide feeding currents. This situation was magnified in a giant colony of the trepostome Tabulipora from the Early Permian Kim Fjelde Fm. in eastern North Greenland. This single branch colony fragment had a diameter of 37.5 mm. A block was cut out of the 8- mm thick exozone, and 20 serial tangential peels were made at varying distances from the endozone. Exilazooecial and autozooecial chamber cross-sectional area, packing, spacing, and wall thickness were measured in the maculae and intermacular areas. Results indicate that, in this colony, volumetric space in the exozone was occupied by budding new exilazooecia in the maculae and by exozonal budding: budding of new exilazooecia in the intermacular areas that transform into autozooecia. Exilazooecia played a dominantly space-filling role in the maculae as well as helped to maintain regular spacing of autozooecia in the intermacular areas.  相似文献   

16.
Lower Permian Bryozoan fauna of Jamal Formation, exposed in Bagh-e Vang (Shotori Mountains, northeast Iran) includes six species. Three species – Streblotrypa (Streblascopora) marmionensis (Etheridge 1926), Rhabdomeson bispinosum (Crockford 1944) and Alternifenestella kungurensis (Stuckenberg 1898) – indicate the Lower Permian (Artinskian to Kungurian) age of the formation. Three additional taxa – Fistulipora sp. 1, Fistulipora sp. 2 and undetermined timanodictyid bryozoan ?Timanodictya sp. could not be identified at the species level. The investigated fauna refers to Uralian and Australian palaeobiogeographic provinces.  相似文献   

17.
Lacertoid footprints are the largest component of the Upper Permian Arenaria di Val Gardena Formation ichnofauna that contains hundreds of specimens mostly referred to the ichnogenus Rhynchosauroides Maidwell 1911. In this paper, we analyzed unpublished material and re-examined the Rhynchosauroides footprints of that ichnofauna, in particular the figured specimens. Analysis of Rhynchosauroides and its type ichnospecies R. rectipes Maidwell 1911 was first necessary. This preliminary investigation highlighted several problems, including ichnospecies named on the basis of poorly preserved material and in some cases significantly different from the type ichnospecies.

The study allowed for recognition of three ichnotaxa referred to Rhynchosauroides: Rhynchosauroides pallinii Conti et al., 1977, Rhynchosauroides isp.1 and Rhynchosauroides isp.2 and Ganasauripus ladinus igen. et isp. nov. Other material previously referred to Rhynchosauroides is herein regarded as unclassifiable, in the light of present ichnological knowledge and procedures.  相似文献   

18.
The Lower Permian in the central Southern Alps yields an important low-diversity fossil assemblage which was deposited in a varied continental setting, showing mainly alluvial fan to lacustrine and, locally, playa-like floodplain environments. The present study is not taxonomical and its objective is to make a first report of new invertebrate organisms and trackways discovered in the Orobic and Collio basins. Such a fossil record, which comprises freshwater jellyfishes, arthropod tracks, stromatolites, algae and other organisms, will further our knowledge about the local and regional geological history of the central-western Southern Alps and improve our understanding of Early Permian palaeoenvironments. On the whole, in both intramontane basins the ichnodiversity and fossil content decreases from a stratigraphic lower portion, mainly lacustrine and alluvial, towards an upper one, characterised by coarse alluvial deposits to floodplain fines. On the basis of both the already known palaeontological data from the two basins, mainly macroflora and tetrapod footprint associations, and the recently discovered taxa, we tried to make reliable palaeoenvironmental inferences and, possibly, hypothesise on a climatic change, which could have occurred during the Early Permian.  相似文献   

19.
Diethard Sanders  Karl Krainer 《Facies》2005,51(1-4):522-540
During the Early Permian, in the area of the Carnic Alps, a quartz-gravelly beach fringed a mixed siliciclastic-carbonate lagoon with fleshy algal meadows and oncoids; seaward, an ooid shoal belt graded down dip to a low-energy carbonate inner shelf with phylloid algal meadows. In limestones, foraminiferal biomurae and bioclast preservation record tapholoss by rotting of non-calcified organisms (interpreted as fleshy algae) and by dissolution of aragonitic fossils. Carbonate loss by dissolution was counteracted and, locally, perhaps exceeded by carbonate precipitation of encrusting foraminifera and as oncoids. Sites of abrasion and carbonate dissolution (beach), sites with tapholoss by rotting and dissolution, but with microbialite/foraminiferal carbonate precipitation (lagoon, inner shelf), and sites only of carbonate precipitation (ooid shoals) co-existed on discrete shelf compartments. Compartmentalized, contemporaneous carbonate dissolution and precipitation, to total amounts yet difficult to quantify, impede straightforward estimates of ancient carbonate sediment budget.  相似文献   

20.
In the Eastern Southern Alps of northern Italy (Carnic Prealps, Friuli region), the shallow-water carbonate platform deposits of the Dolomia Principale Fm. (Norian–Rhaetian, Upper Triassic) show best-preserved platform to basin facies transition. The palaeontological study of an algal-rich level recovered from the platform margin facies (Mt. Pramaggiore) has displayed a very interesting association of Dasycladales. Two new genera (Bystrickyella and Elliottporella) and four new species (Bystrickyella ottii, Elliottporella morelloae, Palaeodasycladus lorigae and Holosporella conradii) have been described. These new data suggest that the Norian represents a period of turnover in the evolutionary history of the green algae community. This stage, placed between two extinctions, end-Ladinian and end-Norian, is here interpreted as a re-organization period of the evolutionary schemes of Dasycladales. The new lineages originated in the Norian developed further and characterized the Early Jurassic scenery. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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