998 resultados para Vertebrates, Fossil - China


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Mode of access: Internet.

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Mode of access: Internet.

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"Second impression March 1936."

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Mode of access: Internet.

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Shipping list no.: 93-0259-P.

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"The accompanying plates were prepared and printed by the United States government for the Report on Tertiary Vertebrata by E. D. Cope, forming volumes III and IV of the final report of the Geological and geographical survey of the territories, F. V. Hayden in charge. The first part of this Report (volume III) treating of the Eocene and a part of the Oligocene vertebrates was completed and published in 1885. The second part, treating of the remainder of the Oligocene and all the Miocene vertebrates was never completed. A large number, but not all, of the plates for this part were prepared and printed, together with seven plates for a contemplated report on Permian Vertebrata.

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A diverse and well-preserved fossil wood assemblage is described, for the first time, from the Middle Permian Taerlang Formation and the Upper Permian Quanzijie Formation in the vicinity of the Tianshan Town, Hami City of northwestern China. On the basis of wood microstructure, the fossil woods are classified into three genera and five species, including one new genus: Prototianshanoxylon gen. nov. and two new species: Prototianshanoxylon erdaogouense sp. nov., Prototianshanoxylon hamiense sp. nov. The new genus is characterized by window-like cross-field pitting and mixed tracheid radial wall pitting that suggest a transitional type between araucarioid-type and protopinoid-type pittings.Phytogeographically, the fossil wood assemblage is characterized by an admixture of elements of both temperate Angaran (represented by wood specimens with moderately to well defined growth rings in their secondary xylem) and tropical-subtropical north subregion of the Cathaysian floras (with wood specimens lacking well-defined growth rings). Such a phytogeographically mixed fossil wood assemblage is interpreted to represent a transitional and complex climate condition between a cool temperate and tropical to subtropical zones, showing both seasonal variation and unstable climate conditions. Previously, similarly mixed floras have already been found to exist widely in northern China ranging in age from Early to Late Permian, but the mechanisms thought to be responsible for their formation were varied and remain controversial. In this study, the formation of these mixed Permian floras of North China is linked to the closure of the Tianshan-Hingan seaway coupled with the collision and amalgamation of Siberia with North China and the Tarim block, in a manner much like closing a pair of scissors with the closure of the seaway proceeding gradually and progressively from west to the east.

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Source quantification of carbonaceous aerosols in the Chinese outflow regions still remains uncertain despite their high mass concentrations. Here, we unambiguously quantified fossil and nonfossil contributions to elemental carbon (EC) and organic carbon (OC) of total suspended particles (TSP) from a regional receptor site in the outflow of Northeast China using radiocarbon measurement. OC and EC concentrations were lower in summer, representing mainly marine air, than in other seasons, when air masses mostly traveled over continental regions in Mongolia and northeast China. The annual-mean contribution from fossil-fuel combustion to EC was 76 ± 11% (0.1−1.3 μg m−3). The remaining 24 ± 11% (0.03−0.42 μg m−3) was attributed to biomass burning, with slightly higher contribution in the cold period (∼31%) compared to the warm period (∼21%) because of enhanced emissions from regional biomass combustion sources in China. OC was generally dominated by nonfossil sources, with an annual average of 66 ± 11% (0.5−2.8 μg m−3), approximately half of which was apportioned to primary biomass burning sources (34 ± 6%). In winter, OC almost equally originated from primary OC (POC) emissions and secondary OC (SOC) formation from fossil fuel and biomass-burning sources. In contrast, summertime OC was dominated by primary biogenic emissions as well as secondary production from biogenic and biomass-burning sources, but fossil-derived SOC was the smallest contributor. Distinction of POC and SOC was performed using primary POC-to-EC emission ratios separated for fossil and nonfossil emissions.

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Abundant, exceptionally preserved coprolites are documented from the Luoping biota (Anisian, Middle Triassic) of Yunnan Province, southwest China. These coprolites can be categorized into fourmorphological types: A) bead to ribbon-shaped, B) short to long cylindrical-shaped, C) flattened, disk-like, and D) segmented faeces. Detailed multi-disciplinary studies reveal that coprolite type A was likely produced by invertebrate animals,while coprolite types B to D could be faeces generated by carnivorous fishes or marine reptiles, perhaps from different taxonomicgroups. When compared with coprolites reported from the Lower Triassic, the Luoping forms indicate more complicated predation-prey food web networks. These evidences, combined with body fossil discoveries fromLuoping, suggest the emergence of complex trophic ecosystems in the Anisian,marking the full biotic recovery following the Permian–Triassic Mass Extinction.