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1.
Summary A rather diverse gastropod fauna from Sarmatian deposits of the Austrian/Hungarian Eisenstadt-Sopron Basin was studied. The fauna derives from two layers of clay and silt within a siliciclastic section at St. Margarethen in Burgenland (Austria). These layers are interpreted as littoral mudflats which formed during the Sarmatian (Late Middle Miocene) along the western coast of the Central Paratethys. Strong shifts in the composition of the gastropod fauna, dominated by Potamididae (Cenogastropoda: Cerithioidea), within each layer indicate successions of limnic-fluvial to oligohaline, brackish-littoral, and marine-littoral environments. These shifts in facies are reflected by an alternational of thePotamides hartbergensis assemblage,Granulolabium bicinctum assemblage, and thePotamides disjunctus assemblage. The speciesJujubinus turriculus (Eichwald, 1850),Gibbula buchi (Dubois, 1831), andCylichnina elongata (Eichwald, 1830) are reported for the first time from the Sarmatian of the Paratethys.Mitrella agenta nov. sp. (Neogastropoda: Columbellidae) is introduced as a new species. These species might represent relics of the diverse Badenian fauna but could also prove a minor ingression of marine species from an adjacent bioprovince in the Late SarmatianMactra “Zone”.  相似文献   

2.
Two collections of clupeid fishes, which have previously been assigned to the species Sardinella sardinites (Heckel, 1850), from the Lower and Middle Sarmatian of the Pshekha River Basin (Western Ciscaucasia, Krasnodar Region) were studied. A new genus, Illusionella gen. nov., with two species, I. tsurevica sp. nov. and I. pshekhensis sp. nov., was described based on morphological characteristics. They are the most abundant species in Sarmatian fish assemblages of the Psekups-Belaya interfluve.  相似文献   

3.
S.Medeanic 《古生物学报》2002,41(4):592-600
摩尔多瓦位于东特提斯地区内,海相,陆相Sarmatian期沉积都很发育,根据软体动物和有孔虫化石,当地Sarmatian期沉积被分为三段,最后从摩尔多瓦各地37口井下和露头700块样品获得的孢粉结果支持Sarmatian期三分,这些孢粉化石资料说明区域性植被响应气候演变,海进,海退等所发生的变化,含有亚热带种类的山毛阔叶林统池了早Sarmatian期,有时暗针叶林增加,在海退期的晚Sarmatian期,含有喜盐植物(Chenopodiaceae,Amaranthus,Artemisia)的草本类增加。已有的资料显示了在东特提斯地区Sarmatian期植被的周期性变化,伴随着亚热带植物不断减少和禾草类不断增加,说明当时气候在朝年均温逐渐降低,干旱化增加,更加大陆性方向变化。  相似文献   

4.
The evolution of important woody plant groups, ancestral to the modern Mediterranean dendroflora, is surveyed. Altogether, the history and phytogeography of 86 fossil species or species-groups is considered. The major part of the Paleomediterranean woody plants appears in Miocene mixed mesophyllous and mesoxerophyllous, evergreen and deciduous forests. The initial formation of basic Mediterranean sclerophyllous woody vegetation types is referred to periods from the Late Sarmatian to the Late Pontian, in geographic areas between 37° and 45° N latitude.  相似文献   

5.
Miocene rissoids from the heterochronous low-salinity seas of the Eastern Paratethys (Early Chokrakian, Karaganian, Late Konkian, Early Sarmatian, and Early Maeotian) were revised. The polyphyletic genus Mohrensternia is subdivided into several generic and subgeneric taxa. The new genus Zhgentia and the new subgenera Rissoa (Turboellina), R. (Pseudoturboellina), and R. (Maeotia) are established.  相似文献   

6.
The Upper Jurassic complex of Zegarowe Rocks is situated on the Kraków–Wieluń Upland in southern Poland. The complex is dominated by massive limestones representing carbonate buildups. The successive stages of carbonate buildup development include: colonisation, aggradational growth and progradation phases. In the colonisation phase, on top of loose peloidal-ooid sands micritic peloidal thrombolites developed. Peloidal and agglutinated thrombolites and stromatolites proliferated during the aggradational growth phase, whereas the progradation phase was characterised by shallowing and related development of agglutinated stromatolites with coprolites. The latter were the effect of periodical stabilisation of detrital sediments by microbial mats. The Zegarowe Rocks complex developed upon an elevation of the Late Jurassic stable northern shelf of the Tethys. This elevation was formed due to local decrease in subsidence rate, induced by the presence of a Palaeozoic granitoid intrusion in the shelf substratum. The carbonate buildups of the Zegarowe Rocks complex, initially developing as sediment-starved mounds upon fault-controlled intraplatform highs under strongly restricted background sedimentation rate, were replaced by agglutinated microbial reefs.  相似文献   

7.
Summary Reduced salintiy and a temperate climate prevailed during the Sarmatian in the Styrian Basin, the westernmost embayment of the Central Paratethys. At its northern margin (in the study area) tectonic processes initiated a transgression causing the incision of a cliff into the metamorphic basement and the formation of a carbonate buildup in the latest Sarmatian. The buildup consists of two serpulid-bryozoan-foraminiferal biostromes separated by a microbialite. Serpulids, bryozoa and the encrusting foraminifer Sinzowella caespitosa (Steinmann) as well as microbial mats formed a rigid framework, in which biogenic debris and siliciclastics were baffled. The different biota show complex growth relationships. Stromatolitic crusts and laminated micritic microbial crusts with birdseyes grew in a small sheltered lagoon. The upper biostrome is truncated by a ravinement surface of eustatic orgin and is overlain by ooid grainstone. The buildup drowned during maximum sea-level rise.  相似文献   

8.
Summary In the top section of the Upper Jurassic profile in the S part of the Cracow-Wielun upland there occur deposits with numerous fragments of the plantonic crinoidsSaccocoma. Sedimentary structures indicate that these deposits are calciturbidites with domination of the redeposited pelagic material. TheSaccocoma-calciturbidites rest on the slope beds of Oxfordian cyanobacterial-sponge carbonate buildups formed in the Polish epicontinental basin, bordering the Tethys ocean in the north. The occurrence of the planktonicSaccocoma seems to be connected with a short deepening the S part of the Polish epicontinental basin in the Late Jurassic. This deepening caused the change within biocoenoses thriving in carbonate buildups and was mainly expressed in reducingTubiphytes. ‘Tubiphytes-reefs’, representing the last stage in the development of the carbonate buildups in the S part of the Cracow-Wielun upland, marked the most shallow sedimentation environment. With deepending of the basin,Tubiphytes and other benthonic forms disappeared, and, simultaneously, the dominant fauna became planktonic. The abundance of planktonic crinoidsSaccocoma (=Lombardia), as well as the presence of planktonic foraminifers, nannoplankton cf.Schizosphaerella, coccoliths and radiolarians indicates a pelagic, open-sea depositional environment. TheSaccocoma-dominated sediments, which had been primarily deposited from a suspension on a sea floor with a distinct relief, became subsequently transported by turbidity currents. A limited extent and thickness of theSaccocoma-calciturbidites was caused by a relatively small amount of the primary material which could be transferred by the turbidity currents because the period of pelagic sedimentation was short. TheSaccocoma-calciturbidites indicate a distinct shift in conditions of sedimentation resulting from over-regional changes and, despite the lack of index fossils, seem to represent a local lithostratigraphic horizon. These sediments probably mark a sedimentation event which caused a minor levelling of the sea floor relief. Then, after a sedimentation break, wide-spread destruction of the tops of carbonate buildups and formation of debris flows in the shallowing Late Jurassic sea took place. TheSaccocoma-calciturbidites in the S part of the Cracow-Wielun upland can be found near edges of horsts. This suggests that the foundations of these horsts are probably of sedimentary origin, dating back at least to the Late Jurassic. TheSaccocoma-calciturbidites in the S part of the Polish epicontinental basin seem to result from local, synsedimentary tectonic movements, which probably reflect over-regional events on the one hand, and oscillations of the sea level-on the other.  相似文献   

9.
New finds of Late Palaeozoic arachnids, based on three well-preserved carapaces from the Carboniferous of Russia and Ukraine and one complete, albeit poorly preserved, specimen from the Permian of Kazakhstan, are described. The spider genus Arthrolycosa is reported from the Late Carboniferous (Late Pennsylvanian: Kasimovian–Gzhelian) of Chunya in the Tunguska Basin of Siberia; it is the first find of a spider outside the Carboniferous tropics. Another fossil assigned to the same genus comes from the Late Carboniferous (Early Pennsylvanian: Bashkirian) of Kamensk–Shakhtinsky in the Donets Basin of Russia; it is probably the oldest fossil spider known. A thelyphonid (whip scorpion) carapace is described from the Late Carboniferous (Late Pennsylvanian: Kasimovian) of the adjacent Lugansk Province of the Donets Basin of Ukraine.  相似文献   

10.
The gastropod family Trochidae from the Sarmatian deposits of the Eastern Paratethys is described in detail. Detailed faunal characteristics of 22 Sarmatian sections in Volyn–Podolia, Moldova, southern Ukraine, and Crimea, some of which have yielded the material of this study, are provided. Based on the study of an extensive collection of Trochidae, the family system is revised. The taxonomic composition of four Trochidae assemblages from Lower and Middle Sarmatian deposits is provided. These assemblages can be used for stratification of the Lower Sarmatian Kuzhorskie and Zbruchskie beds and Middle Sarmatian Novomoskovskie and Dnepropetrovskie–Vasilevskie beds. The results of the biogeographical study of Trochidae development in the Sarmatian basin of the Paratethys are provided. The data obtained on the evolution of Trochidae can be used for resolution of the paleoecological, biogeographical, and biostratigraphic questions.  相似文献   

11.
The Leitha Mountains in Austria are a chain of hills separating the southern Vienna Basin and the Danube Basin. The Lower East Alpine basement of the Leitha Mts. is covered by Middle Miocene sediments of the Badenian and Sarmatian regional stages. Close to the northeastern margin of these hills, upper Badenian successions are exposed, which are part of a coralline algal-dominated carbonate platform with hydrodynamically influenced sediments. Six sections have been logged and subjected to detailed investigation and sampling. They are characterized by inclined beds (foresets), which have been formed by unidirectional transport of sediments. Large-scale asymmetrical ripples indicate strong currents affecting shallow topset deposits. Generally, this hydrodynamically controlled sedimentation, documented by seven facies types, is reflected in a strongly reduced diversity of facies and biota, contrary to the older facies-rich middle Badenian sediments. This change from biologically to hydrodynamically controlled sedimentation led to a reduction in diversity of facies and biota. Sediment transport, however, caused secondary mass occurrences of echinoids or foraminifers derived from seagrass meadows. This study unravels the distribution and differences of middle and upper Badenian deposits of the Leitha Mountains and the influence of tectonic activity. Changes in hydrodynamics on the Leitha Platform are linked to the formation of the Danube Basin starting in the middle Badenian when a new seaway to the southeast has started to form.  相似文献   

12.
A revision of previously known material and analysis of new records of Miocene baleen whales from the Sarmatian of Adygea (city of Maikop, Blinovo Formation) resulted in the establishment of a new genus, Kurdalagonus with three species: K. mchedlidzei sp. nov. (Middle Sarmatian, Nagiezh-Uashkh locality), K. adygeicus sp. nov. (Upper Sarmatian, Hydroelectric power station locality), and K. maicopicus (Spasskii, 1951) (=Cetotherium maicopicum Spasskii, 1951; Middle Sarmatian, Hydroelectric power station locality).  相似文献   

13.
《Palaeoworld》2016,25(2):212-238
Mesozoic strata are well developed and exposed continuously across the Sichuan Basin, South China. In particular, the Upper Triassic strata yield diverse and abundant spore-pollen fossils, providing a significant reference for the study of palaeoenvironmental variations across the Triassic–Jurassic transition where mass extinctions were occurring. In this paper, we summarize the major progress on Late Triassic palynological studies in this basin. To date, 151 genera (454 species) of sporomorph fossils have been reported from the Late Triassic strata in the Sichuan Basin. Three palynological assemblages are distinguished for the Late Triassic in the Sichuan Basin. Late Triassic vegetation in the Sichuan Basin shows a remarkable predominance of ferns, followed by conifers and cycads/ginkgophytes, and conifers show a distinct increase in abundance in the latest Triassic. In general, the Late Triassic palaeoclimate in the Sichuan Basin was tropical-subtropical, humid and warm. A synthesis of the data shows that the Late Triassic did not have a constant palaeoclimate in the Sichuan Basin, several climatic events are recognized: two warm and humid climate events in Norian-Rhaetian time, coupled with a cooler and drier condition in the latest Late Triassic. Further investigations in higher resolution at more continuous sections in the Sichuan Basin are needed to better understand the Late Triassic vegetation response, climate changes, as well as palaeoecosystem variations across the Triassic–Jurassic boundary.  相似文献   

14.
Summary Isolated sponge bioherms are documented from the Lower Ordovician Makkol Formation of the Taebaek Group in the Taebaeksan Basin, mideast Korea. They are formed by an association of a lithistid spongeArchaeoscyphia, a receptaculidCalathium and stromatolitic algae, and share many features with the Lower Ordovician buildups known elsewhere. These bioherms were established in an incised bottom and reached up to about 1 m in height. As the bioherms grew upward, they were more severely affected by intense wave action and frequent storms, which eventually perished the bioherms. The occurrence ofArchaeoscyphia-Calathium association suggests a close biogeographic link between Korea and North China, supporting the paleogeographic model that the Taebaeksan Basin was connected through contiguous shallow waters to North China in the early Paleozoic.  相似文献   

15.
16.
中国白垩纪被子植物花粉的宏演化   总被引:15,自引:4,他引:11  
张一勇 《古生物学报》1999,38(4):435-453
根据中国白垩纪被子植物花粉产出记录与形态构造分析以及与世界其它地区产出顺序比较,假设中国白垩纪被子植物花粉的宏演化序列,共划分为10个发育阶段,归于7个形态演化期:1)欧特里夫期至早巴列姆期的无口器类演化期(含:1:1网纹无口器粉发育阶段);2)晚巴列姆至晚阿普梯期的单沟类演化期(含:2:1。棒纹粉发育阶段;2.2,星粉-棒纹粉发育阶段);3)早,中阿尔必期的三沟类演化期(含:3.1,三沟粉类-星  相似文献   

17.
Early Sarmatian bony fish assemblages from the Pshekha River (northern Caucasus) and the village of Naslavcea (northern Moldova) are compared. It is proposed that, in the Early Sarmatian, connection between the North Caucasian and Moldavian basins was hampered and the two fish localities were formed under different conditions. The impoverished taxonomic composition of Sarmatian fishes from the Eastern Paratethys is attributable to unfavorable chemical composition (increased alkalinity) rather than to low salinity.  相似文献   

18.
《Palaeoworld》2022,31(3):443-454
Although liverworts are widely distributed around the world with a large number of extant species, reliable fossil records are relatively rare. Here, we report a new species, Ricciopsis baojishanensis Han and Yan, n. sp. (Ricciaceae) and an unnamed species, Hepaticites sp. from the Late Triassic Nanying’er Formation in Baojishan Basin, Baiyin City, Gansu Province, Northwest China. The generic designation is based on detailed comparison of the gross morphology with related fossil and extant species. The new species is characterized by its rosette-forming thallus, dichotomous branching, ribbon-like segments and entire margins. The current fossils represent the first record of liverwort from the Late Triassic in Baojishan Basin, Gansu Province. Based on the different fossil records of the Ricciaceae, we suggest that these taxa were widely distributed during Late Triassic to Oligocene worldwide, mainly in warm temperate and tropical environments, similar with their current distribution. The discovery of the present fossils indicates that the climate of Baojishan Basin in Late Triassic is warmer and more humid than that of today.  相似文献   

19.
The Kopet-Dagh Basin is located in northeastern Iran and southern Turkmenistan. The Late Maastrichtian Kalat Formation caps the Cretaceous interval in this Basin. Based on eight measured stratigraphic sections, the depositional environments and the sea-level history of the Kalat Formation have been interpreted. Petrographic and field observations led to identification of four major carbonates (A–D) and two siliciclastic lithofacies types. Carbonate rocks were deposited on a ramp setting within three zones including restricted and semi-restricted lagoons, bars, and open marine environments, while the siliciclastics were deposited at the shoreline. Sequence stratigraphic analysis identified two depositional sequences in the western and eastern parts and three depositional sequences in the central parts of the study area. Comparing the sea-level curve of Late Maastrichtian time in the Kopet-Dagh Basin with the global sea-level curve for the same time interval, there are some geometrical similarities and differences. The variations in the Basin are related to regional tectonic settings and sediment loading of the study area. Reconstructions of depositional environment during eight time slices of the Late Maastrichtian are presented. These results could be used for comparison with other localities worldwide and provide additional data for Late Cretaceous paleogeographic reconstructions.  相似文献   

20.
《Geobios》2016,49(3):201-209
Numerous ascidian spicules are reported for the first time from the lower Sarmatian Darabani-Mitoc Clays of Costeşti, north-western Moldova. The biological interpretation of the studied sclerites allows distinguishing at least three morphospecies (Polysyncraton-like, Trididemnum-like, and Didemnum-like) within the Didemnidae family. Eight other morphological types of spicules are classified as indeterminate didemnids. Most of the studied spicules are morphologically similar to those of Recent shallow-water taxa from the Mediterranean Sea. In contrast, some sclerites resemble those of taxa from the Indo-Pacific region. The greater size of the studied spicules, compared to that of present-day didemnids, suggests favorable physicochemical conditions within the Sarmatian Sea. The presence of these stenohaline tunicates that prefer normal salinity seems to confirm latest hypotheses regarding mixo-mesohaline conditions during the early Sarmatian.  相似文献   

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