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Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications
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作者 Tao Yang Jia-Hao Cai +9 位作者 Yan-Zhi Dai Hong-Yu Chen Lei Han Li Zhang Wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu San-Ping Xie De-Fei Yan 《Plant Diversity》 SCIE CAS CSCD 2024年第1期101-115,共15页
Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investiga... Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau.However,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is poor.Here,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis.These findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene.The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene.This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic conditions.Indeed,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene. 展开更多
关键词 PALEOENVIRONMENT BIOGEOGRAPHY Betulaceous fossil Qaidam basin Tibetan Plateau OLIGOCENE
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The Homines Fossilization: Brief Review of Anthropocene
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作者 Christiano Magini 《Open Journal of Geology》 CAS 2024年第3期298-316,共19页
This article is an insight into our lifetime and the enduring capacity of the planet—especially regarding water and space, in face of the Homines population growth. This is and will be recorded in the geological time... This article is an insight into our lifetime and the enduring capacity of the planet—especially regarding water and space, in face of the Homines population growth. This is and will be recorded in the geological time: once preserved as human fossils, we will be part of a chapter in Earth’s history. A brief taphonomic chronology is presented, from the emergence of humans to the domination of the environment and supremacy over other species, and also a concern on how much planet Earth can bear Homines neglects. The objective of this review is to show that the strata that contain human fossils change during the Anthropocene not only the human body but also its tools, resulting from its development. Four stages were identified as taphonomic phases: the first wave, when organic Homines fossils were preserved only with materials in natura, including natural artefacts. The second fossilization phase has occurred and still occurs with the urban Homines, a product of the proliferation of cities, including anthropogenic waste and diseases. The technology that we master today also belongs to our taphonomy: hydrocarbons, metals, plastic, radioactive elements—all fossilize together with the industrial Homines, representing the third fossilization phase, which is very close to the fourth fossilization phase, where our enlightened intelligence buries the technological Homines together with his world of digital waste and new viruses. How will we fossilize the future? This question makes us think about the behavior we assume today—who or what will go to the grave with us, which geological/environmental response will stop superpopulation, which extinction event will hold human proliferation? Which will be the mineral, human and waste components of our subsequent strata? How much water and space can we still use without causing a global environmental collapse? 展开更多
关键词 Homines fossilIZATION ANTHROPOCENE
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Dating Suborder Polypodiineae (Eupolypods I) with Its Oldest Fossil
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作者 Chunxiang Li Junye Ma 《Open Journal of Geology》 CAS 2024年第10期929-942,共14页
Inferring divergence times between lineages is crucial for understanding biological evolutionary processes. The extraordinary species diversity of Eupolypods within the fern lineage has been interpreted as an ecologic... Inferring divergence times between lineages is crucial for understanding biological evolutionary processes. The extraordinary species diversity of Eupolypods within the fern lineage has been interpreted as an ecological opportunistic response to the emergence of more complex, angiosperm-dominated ecosystems. This co-adaptation between Eupolypods and angiosperms has prompted ongoing investigations into the phylogenetic and diversification timelines of Eupolypods. In this study, we incorporate newly discovered fossils of Dryopteridaceae, including two species from both the stem and crown groups, to reanalyze the phylogenetic and diversification times of Eupolypods using total-evidence dating (TED or tip-dating) methods. Our analyses confirm that Eupolypods first diversified during the Jurassic and suggest that both subclades, Polypodiineae and Aspleniineae, underwent their earliest diversification during this period, challenging recent claims that Polypodiineae diversified no earlier than the Cretaceous. These results support a “long fuse” model, indicating that the initial emergence of Polypodiales preceded their diversification and extensive fossil record. Furthermore, our findings clarify the systematic position of Hypodematiaceae, indicating that it, along with Didymochlaenaceae, represents the basal lineages of Polypodiineae. This study highlights the critical role of fossil abundance and taxonomic composition in molecular dating analyses. 展开更多
关键词 Eupolypods Polypodiineae Dryopteridaceae fossils Bayesian Tip-Dating
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pyIFPNI:A package for querying and downloading plant fossil data from the IFPNI
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作者 Bailong Zhao 《Plant Diversity》 SCIE CAS CSCD 2024年第2期280-282,共3页
The International Fossil Plant Names Index(IFPNI,2014-onwards)not only serves as an online gateway to the fossil plant name registry for the global scientific community,but also serves as a comprehensive and dynamic a... The International Fossil Plant Names Index(IFPNI,2014-onwards)not only serves as an online gateway to the fossil plant name registry for the global scientific community,but also serves as a comprehensive and dynamic archive of fossil plants(Doweld,2016,2022).Since its establishment in 2014,the IFPNI has accumulated more than 80,000 entries of fossil plant names,along with information on over 10,000 documents and over 6000 paleobotanists,all supported by exhaustive data,demonstrating the scope of the IFPNI's work(IFPNI,2014-onwards). 展开更多
关键词 PLANT fossil
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Inner Ear of Miocene Fossil Ape Gives Clues to Evolution of Bipedalism
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《Bulletin of the Chinese Academy of Sciences》 2024年第1期59-60,共2页
Anew study of a 7–8-million-year-old extinct fossil ape from China called Lufengpithecus offers new insights into the evolution of human bipedalism.The study,published in The Innovation,was conducted by a team from t... Anew study of a 7–8-million-year-old extinct fossil ape from China called Lufengpithecus offers new insights into the evolution of human bipedalism.The study,published in The Innovation,was conducted by a team from the Institute of Vertebrate Paleontology and Paleoanthropology(IVPP)of the Chinese Academy of Sciences,the Yunnan Institute of Cultural Relics and Archaeology(YICRA),and New York University(NYU). 展开更多
关键词 insight EVOLUTION fossil
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New Discoveries of Phaeophycean Fossils in the Early Cambrian, Haikou, Kunming,Yunnan, Southwest China 被引量:1
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作者 徐兆良 《Acta Botanica Sinica》 CSCD 2001年第10期1072-1076,共5页
The paper deals with the new phaeophycean fossils in the Early Cambrian from Chengjiang Biota at Ercai Village of Haikou, Kunming, Yunnan, Southwest China. Three new taxa, Punctatiopsis latifolia gen. et sp. nov., P. ... The paper deals with the new phaeophycean fossils in the Early Cambrian from Chengjiang Biota at Ercai Village of Haikou, Kunming, Yunnan, Southwest China. Three new taxa, Punctatiopsis latifolia gen. et sp. nov., P. simplex gen. et sp. nov. and Vendotaenia cf. antiqua Gnilovskaya axe described here in detail. These new findings show that the Chengjiang Biota is high in species diversity of fossil algae and might offer new evidence for a better understanding of the Cambrian explosive biological evolution. The fossil genus described here is found to have a close relationship with the living Punctatia based on similar morphology. The results suggest that the Chengjiang Biota in Haikou area of Kunming was living in an intertidal and subtidal seawater environment. 展开更多
关键词 Haikou of Yunnan Early Cambrian phaeophycean fossils
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Estimating ancestral distributions of lineages with uncertain sister groups:a statistical approach to Dispersal-Vicariance Analysis and a case using Aesculus L.(Sapindaceae) including fossils 被引量:9
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作者 A.J.HARRIS 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期349-368,共20页
We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimiz... We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimized for a sample of Bayesian trees. The probability P of an ancestral range r at a node is then calculated as P(rY) = ∑t^n=1 F(rY)t Pt where Y is a node, and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y, t is one of n topologies optimized, and Pt is the probability of topology t. Node Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x", where x may vary due to phylogenetic uncertainty (polytomies and nodes with posterior probability 〈 100%). Using this method, the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of interest. This approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA optimization. It is an extension of the previously described method called Bayes-DIVA, which pairs Bayesian phylogenetic analysis with biogeographic analysis using DIVA. Further, we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp*F(rY) on the Bayesian consensus tree when both variables are 〈 100%, where pp is the posterior probability and F(rY) is the frequency of range r for the node containing the specific crown group. We tested our DIVA-Bayes approach using Aesculus L., which has major lineages unresolved as a polytomy. We inferred the most probable geographic origins of the five traditional sections of Aesculus and ofAesculus californica Nutt. and examined range subdivisions at parental nodes of these lineages. Additionally, we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic analysis. Our analysis resolved the geographic ranges of the parental nodes of the lineages of Aesculus with moderate to high probabilities. The probabilities were greater than those estimated using the simple calculation ofpp*F(rY) at a statistically significant level for two of the six lineages. We also found that adding fossil wildcard taxa in phylogenetic analysis generally increased P for ancestral ranges including the fossil's distribution area. The AP was more dramatic for ranges that include the area of a wildcard fossil with a distribution area underrepresented among extant taxa. This indicates the importance of including fossils in biogeographic analysis. Exmination of range subdivision at the parental nodes revealed potential range evolution (extinction and dispersal events) along the stems ofA. californica and sect. Parryana. 展开更多
关键词 AESCULUS biogeography DIVA fossil wildcards MRBAYES phylogenetic uncertainty.
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The First Observation on Plant Cell Fossils in China 被引量:4
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作者 WANG Xin CUI Jinzhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第1期16-22,共7页
For a long time, paleontologists have been focusing on hard parts of organisms during different geological periods while soft parts are rarely reported. Well-preserved plant cells, if found in fossils, are treated onl... For a long time, paleontologists have been focusing on hard parts of organisms during different geological periods while soft parts are rarely reported. Well-preserved plant cells, if found in fossils, are treated only as a rarity. Recent prowess in research on fossil cytoplasm indicates that plant cytoplasm not only has excellent ultrastructures preserved but also may be a quite commonly seen fossil in strata. However, up to now there is no report of plant cell fossils in China yet. Here plant cell fossils are reported from Huolinhe Coal Mine (the early Cretaceous), Inner Mongolia, China. The presence of plant cytoplasm fossils in two cones on the same specimen not only provides further support for the recently proposed hypothesis on plant cytoplasm fossilization but also marks the first record of plant cytoplasm fossils in China, which suggests a great research potential in this new area. 展开更多
关键词 fossil cells PLANT China CRETACEOUS
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Calcareous Nannofossils and Molecular Fossils in Cobalt-rich Crusts and their Response to the P/E Global Event 被引量:6
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作者 ZHANG Haisheng ZHAO Jun +4 位作者 HAN Zhengbing LU Bing WU Guanghai PULYAEVA I.A. 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1264-1274,共11页
A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of ca... A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of calcareous nannofossils and other fossil species suggests six age ranges for the nannofossils: late Cretaceous, late Paleocene, (early, middle, late) Eocene, middle Miocene, late Pliocene, and Pleistocene. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were used to test the Co-rich crusts, and a variety of molecular fossils were detected, such as chloroform bituminous "A" , n-alkane, isoprenoid and sterol. Peak carbon and molecular indices (such as C23-/C24+, CPI, Pr/Ph, Pr/nC17, Ph/nCxs and j13C) indicate that the parent organic matter is dominated by marine phytoplankton and thallogen whereas there is little input of terrestrial organic matter. Researches on calcareous nannofossils, molecular fossils and molecular organic geochemistry data reveal that the Paleocene/Eocene (P/E) global event is recorded in the cobalt- rich crusts from the northwestern Pacific Ocean. A succession of biomes can be observed near the 85 mm boundary (about 55 Ma), i.e., the disappearance of the late Cretaceous Watznaueria barnesae and Zigodicus spiralis, and Broisonia parka microbiotas above the P/E boundary, and the bloom of Coccolithus formosus, Discoaster multiradiatus, Discoaster mohleri and Discoaster sp. below the boundary. Typical parameters of molecular fossils, such as saturated hydrocarbon components and carbon-number maxima, Pr/Ph, Pr/C17, Ph/C18, distribution types of sterols, Ts/Tm ratios and bacterial hopane, also exhibit dramatic changes near the P/E boundary. These integrated results illustrate that the biome succession of calcareous nannofossils, relative content of molecular fossils and molecular indices in the cobalt-rich crusts near the 85 mm boundary faithfully record the P/E global event. 展开更多
关键词 Late Cretaceous cobalt-rich crust calcareous nannofossils molecular fossils Paleocene-Eocene boundary PETM
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Trace Fossils from Lower Cambrian Wusongger Formation in Xiaoerbulake Outcrop,Kalpin Area,Xinjiang 被引量:6
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作者 BAI Zhongkai LU Xiuxiang +3 位作者 LIU Xiaoping XIE Qilai LI Jianjiao WU Jianjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期313-319,共7页
Based on the analysis of trace fossils collected from the typical outcrop of the Lower Cambrian Wusongger Formation in the Kalpin area, ten ichnospecies of six ichnogenus were identified in the upper member of the Wus... Based on the analysis of trace fossils collected from the typical outcrop of the Lower Cambrian Wusongger Formation in the Kalpin area, ten ichnospecies of six ichnogenus were identified in the upper member of the Wusongger Formation, with most of them being found for the first time. The trace fossils are described seriatim. The ichnospecies are mainly represented by such common trace fossils as Ophiomorpha nodosa, Helminthopsis hieroglyphica, Helminthopsis ichnosp., Planolites beverleyensis, Planolites vulgaris, Planolites montanus, Palaeophycus striatus, Palaeophycus curvatus, Cochlichnus anguineus and Rituichnus elongatum. The trace fossils are of high diversity and low abundance, and can be diagnosed as the Cruziana ichnofacies. They can be interpreted as having formed in a shallow water environment. 展开更多
关键词 trace fossils Wusongger Formation Lower Cambrian Kalpin area
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Flysch Trace Fossils from the Hercynian and IndosinianOrogenic Belts of North western China andTheir Palaeoenvironmental Significance 被引量:6
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作者 Gong Yiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期384-394,495-499,共16页
Twenty-three ichnotaxa have been found in the Silurian and Carboniferous turbidites of the Tianshan orogenic belt and the Triassic turbidites of the East Kunlun-West Qinling orogenic belt of northwestern China. They a... Twenty-three ichnotaxa have been found in the Silurian and Carboniferous turbidites of the Tianshan orogenic belt and the Triassic turbidites of the East Kunlun-West Qinling orogenic belt of northwestern China. They are Acanthorhaphe isp., ?Arthrophycus isp., Aulichnites parkerensis, Chondrites isp., C. intricatus, C. targionii, Cochlichnus anguineus, coprolite, Dendrotichnium haentzscheli, Helminthopsis isp., Helminthopsis abeli, H. hieroglyphica, H. cf. irregularis, Imbrichnus isp., Kunlunichnus qinghaiensis, Laevicyclus rotaeformis, Lophoctenium tianshanensis, Megagrapton isp., Micatuba verso?, Muensteria isp., Neonereites, Palaeophycus, and Zoophycos caudagalli, two of which, namely, Kunlunichnus qinghaiensis and Lophoctenium tianshanensis, are new ichnospecies. The described trace fossils can be grouped into five ichno-assemblages: the Aulichnites-Imbrichnus ichno-assemblage representing turbidity current deposits of a restricted anoxic deep-sea basin, the Lophoctenium ichno-assemblage showing the deep-sea or ocean environments relevant to a plate subduction, the Zoophycos-Helminthopsis ichnoassemblage representing the upper-middle turbidity fan deposits of a pelagic and hemipelagic environment, the Megagrapton-Chondrites ichno-assemblage representing the middle-lower turbidity fan deposits of an oceanic archipelago and the Kunlunichnus ichno-assemblage indicating bathyal turbidity current deposits. 展开更多
关键词 flysch trace fossils Silurian Carboniferous Triassic Tianshan Mountains Kunlun Mountains orogenic belt northwestern China
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Vestrogothia spinata(Phosphatocopina,Crustacea),Fossils of Orsten-type Preservation from the Upper Cambrian of Western Hunan,South China 被引量:6
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作者 LIU Zheng DONG Xiping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期471-478,共8页
Fossils of Orsten-type preservation represented by the crustacean Skaracarida and Phosphatocopida were found in western Hunan, South China in 2005, including the important phosphatocopid species Vestrogothia spinata b... Fossils of Orsten-type preservation represented by the crustacean Skaracarida and Phosphatocopida were found in western Hunan, South China in 2005, including the important phosphatocopid species Vestrogothia spinata based on exquisitely preserved soft-bodied specimens that allow the first growth stage to be reestablished. The taxonomy of Vestrogothia spinata is revised employing the character of a two-divided limb stem of the mandible. A new foundation for the phylogeny of the Phosphatocopina using mandible characters related to crustacean appendages is postulated. Vestrogothia spinata has only previously been found from Sweden. 展开更多
关键词 Vestrogothia spinata Phosphatocopina CRUSTACEA Orsten-type fossil taxonomy ontogeny Upper Cambrian HUNAN South China
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A New Idea of Sinian Doushantuo'an Metaphyte Fossils from Xiuning, Anhui Province 被引量:5
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作者 Tang Feng, National Geological Museum of China, Xisi, Beijing 100034Yin Chongyu and Gao LinzhiInstitute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang, Beijing 100037 Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第4期491-501,515-517,共14页
This paper gives a summary of the fossil data from the Sinian Doushantuo' an Lantian Formation in the Xiuning area, Anhui Province, China, and reports the genital butt structure comparable to that of some modern a... This paper gives a summary of the fossil data from the Sinian Doushantuo' an Lantian Formation in the Xiuning area, Anhui Province, China, and reports the genital butt structure comparable to that of some modern advanced algae and the fossil structure comparable to the dehiscence of sporangia as well as the ontogenetic phenomenon occurring possibly from the formation of embryos by zygote germination to the production of sessile benthonic algal adults. This phenomenon furnishes a useful clue to the further study of the life history of alternate generations in advanced algae and provides megafossil evidence for the sex differentiation of metaphytic algae. 展开更多
关键词 Doushantuo' an stage metaphyte fossil reproductive structure alternation of generations Xiuning ANHUI
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The environmental implication of diatom fossils in the surface sediment of the Changjiang River estuary(CRE) and its adjacent area 被引量:3
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作者 FAN Xin CHENG Fangjin +1 位作者 YU Zhiming SONG Xiuxian 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期552-567,共16页
In order to depict the distribution of diatom fossils in surface sediments and to establish a reliable reference data for further paleoenvironmental study in the Changjiang (Yangtze) River estuary and its adjacent wat... In order to depict the distribution of diatom fossils in surface sediments and to establish a reliable reference data for further paleoenvironmental study in the Changjiang (Yangtze) River estuary and its adjacent waters, the diatom fossils from 34 surface sediment samples and their relationship with environmental variables were analyzed by principal component analysis and redundancy correspondence analysis. The diversity and abundance of diatom fossils were analyzed. Some annual average parameters of the overlying water (salinity, temperature, turbidity, dissolved oxygen, depth, dissolved inorganic nitrogen, dissolved inorganic phosphate and dissolved inorganic silicate) were measured at each sampling site. A total of 113 diatom taxa and one silicoflagellate species were identified in the investigation area. Diatom fossils were better preserved in fine sediments. The absolute abundance of diatom fossils did not significantly diff er between inshore and off shore areas, the species diversity decreased from inshore to off shore. This may be because high nutrients and low salinity promoted the growth of more brackish species in coastal waters. The diatom taxa were divided into three groups, on the basis of their response and indication to environmental changes. For example, Actinocyclus ehrenbergii and Cyclotella stylorum were dominant in coastal waters (Group 1 and Group 3) with high nutrients and low salinity;the relative abundances of Paralia sulcata and Podosira stelliger were significantly higher in off shore sites (Group 2, average 39.5%), which were characterized by high salinity and deep water. Four environmental variables (salinity, dissolved inorganic nitrogen, temperature and water depth) explained the composition and distribution of diatom taxa independently ( P< 0.05), this finding can be applied in further paleoenvironmental reconstruction research in this area. 展开更多
关键词 DIATOM fossils CHANGJIANG River ESTUARY surface SEDIMENTS environmental variables
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New Small Shelly Fossils(Acanthocassis and Xinlispina Gen.Nov.) from the Fortunian Stage(Early Cambrian) in Southern China 被引量:2
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作者 SHAO Tiequan LIU Yunhuan +9 位作者 WANG Qi ZHANG Huaqiao TANG Hanhua CAO Xi HE Huahua ZHANG Yanan LI Yuan ZHENG Panlin ZHU Chengyu HU Jiaxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第5期1470-1481,共12页
We describe new material of three-dimensionally phosphatized small shelly fossils Acanthocassis and Xinlispina gen.nov.from the Fortunian Stage(early Cambrian) of southern Shaanxi and northern Sichuan Provinces.The ... We describe new material of three-dimensionally phosphatized small shelly fossils Acanthocassis and Xinlispina gen.nov.from the Fortunian Stage(early Cambrian) of southern Shaanxi and northern Sichuan Provinces.The new materials allow description of the delicate morphology of these skeletons, and also their skeletogenesis.Acanthocassis and Xinlispina have comparable morphological features: a main branch and radially arranged sub-branches.They differ from each other in many details, e.g., the presence of a single central branch only in Xinlispina, and the presence of small nodes only in Acanthocassis.Acanthocassis cannot be a naked anthopolyp or hydropolyp because of the more-or-less stiffened cuticle and the absence of a mouth.Acanthocassisand Xinlispina differ from coeval sponge spicules and chancelloriid sclerites and rosettes of crossed pedicellariae of echinoderms, and might be cuticular ornaments of animals of unclear affinities.They occur in the first small shelly fossil assemblage zone, and could be adopted as auxiliary fossils for biostratigraphic correlation in southern China. 展开更多
关键词 small shelly fossils Fortunian Stage CAMBRIAN Xinli Section Xixiang Section Southern China
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Leaf fossils of Sabalites(Arecaceae)from the Oligocene of northern Vietnam and their paleoclimatic implications 被引量:3
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作者 Ai Song Jia Liu +10 位作者 Shui-Qing Liang Truong Van Do Hung Ba Nguyen Wei-Yu-Dong Deng Lin-Bo Jia Cedric Del Rio Gaurav Srivastava Zhuo Feng Zhe-Kun Zhou Jian Huang Tao Su 《Plant Diversity》 SCIE CAS CSCD 2022年第4期406-416,共11页
Recent paleobotanical investigations in Vietnam provide a good opportunity to improve our understanding of the biodiversity and paleoclimatic conditions in the geological past of Southeast Asia.Palms(Arecaceae)are a d... Recent paleobotanical investigations in Vietnam provide a good opportunity to improve our understanding of the biodiversity and paleoclimatic conditions in the geological past of Southeast Asia.Palms(Arecaceae)are a diverse family of typical thermophilous plants with a relatively low tolerance for freezing.In this study,we describe well-preserved fossil palm leaves from the Oligocene Dong Ho Formation of Hoanh Bo Basin,northern Vietnam.Characters of the fossil leaves,such as a fan-shaped costapalmate lamina,an unarmed petiole,a costa slightly enlarged at the base that then tapers distally into the blade,and well-preserved amphistomatic leaves with cuticles,suggest that they represent a new fossil species,which we herein designate Sabalites colaniae A.Song,T.Su,T.V.Do et Z.K.Zhou sp.nov.Together with other paleontological and palaeoclimatic evidence,we conclude that a warm climate prevailed in northern Vietnam and nearby areas during the Oligocene. 展开更多
关键词 fossil LEAF OLIGOCENE PALEOCLIMATE Palm Vietnam
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High Temperature as a Mechanism for Plant Cytoplasm Preservation in Fossils 被引量:1
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作者 WANG Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期183-193,共11页
Because the cytoplasm of a plant normally degrades after the death of the plant, finding cytoplasm in a plant body after a prolonged period of time, especially in fossil plants, is unexpected. Recent work on several 1... Because the cytoplasm of a plant normally degrades after the death of the plant, finding cytoplasm in a plant body after a prolonged period of time, especially in fossil plants, is unexpected. Recent work on several 100-Myr-old plant fossils from Kansas, USA indicates, however, that cells and their contents can be preserved. Most of the cells in these fossil plants appear to be in a state of plasmolysis, and these fossil cells bear a strong resemblance to laboratory-baked cells of extant plant tissues. Based on a comparison with extant material plus biophysical and biochemical analyses of the cytoplasm degrading process, a new hypothesis for cytoplasm preservation in nature is proposed: high temperature, a concomitant of commonly seen wildfires, may preserve cytoplasm in fossil plants. This hypothesis implies that fossilized cytoplasm should be rather common and an appropriate substance for research, unlike previously thought. Research on fossil cytoplasm closely integrates paleobotany with biochemistry, biophysics, as well as fire ecology, and invites inputs from these fields to paleobotany to interpret these provocative findings. 展开更多
关键词 CRETACEOUS wildfire fossil high temperature plant cytoplasm
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The geological significance of fossils in the coastal loess in the Bohai Straits and Liaodong Peninsula 被引量:1
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作者 Cheng Zhenbo, Fu Mingzuo and Ju Xiaohua First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第1期71-83,共13页
Based on the analysis of the characteristics of the fossils (mollusks, Radiolaria, planktonic and benthic Foraminifera and Ostracoda) found in the four loess profiles located respectively at Heishigou and Beizhuang Vi... Based on the analysis of the characteristics of the fossils (mollusks, Radiolaria, planktonic and benthic Foraminifera and Ostracoda) found in the four loess profiles located respectively at Heishigou and Beizhuang Villages on Daheishan Island in the Miaodao Islands in the Bohai Straits, and Daweijia and Yujiawaizi Villages in Jinzhou County, Liaodong Peninsula, the distribution and abundance variation of the fossils in vertical profiles are studied, the source of coastal loess is probed and the relationship between loess deposition and paleoclimatic environment as well as sea-level changes is discussed. 展开更多
关键词 Coastal loess material source fossil organisms PALEOCLIMATE
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Identification of bacterial fossils in marine source rocks in South China 被引量:1
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作者 Baojian Shen Jianzhong Qin +3 位作者 Borjigin Tenger Anyang Pan Yunfeng Yang Lizeng Bian 《Acta Geochimica》 EI CAS CSCD 2018年第1期68-79,共12页
Based on the results of conventional geochemistry analysis including thin sections and SEM observations, different shapes of bacterial fossils, with size ranging from dozens of nanometers to several microns, were disc... Based on the results of conventional geochemistry analysis including thin sections and SEM observations, different shapes of bacterial fossils, with size ranging from dozens of nanometers to several microns, were discovered in the low-mature marine source rocks and coal seams in South China, of which the Permian source rocks were dominated by the bacterial fossils derived from symbiotic sulphur bacteria with gypsum, and the Chengkou section in the Cambrian strata were occupied by abundant nanoscale bacterial fossils with rod and bar shapes. In contrast, a large quantity of possible bacterial fossils found in the high-mature Permian, Silurian, and Cambrian source rocks using SEM need to be further explored. Despite this,this study has indicated that bacterial fossils were prevalent in the source rocks, such as mudstone, siliceous rock and gypsum-bearing coal seams in South China, which has been ignored before. It also suggests that the bacterial fossils may play an important role in the formation and accumulation of shale gas in the geological history. 展开更多
关键词 South China Excellent marine source rocks Bacterial fossil Sedimentary environment
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Stratigraphic Implications of Skeletal Microfossils from the Cambrian of Korea:A Preliminary Report 被引量:1
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作者 Byung-Su LEE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1152-1159,共8页
Diverse small shelly fossils and other associated fossils were recently recovered from the Cambrian Hanaeri section, southwestern Mungyeong, Korea. The fauna includes conoidal problematica, poriferans (sponge spicule... Diverse small shelly fossils and other associated fossils were recently recovered from the Cambrian Hanaeri section, southwestern Mungyeong, Korea. The fauna includes conoidal problematica, poriferans (sponge spicules), coeloscleritophorans (chancelioriids), brachiopods, monoplacophorans, trilobite (?) fragments, echinoderms, and conodonts. A preliminary assessment of faunal associations, stratigraphic implications, and the correlation of these skeletal fossils is given, based on occurrences of Actinotheca cf. mira (He), Microcornus sp., Torellela laevigata (Linnarsson), Torellela sp., Archiasterella quadratina Lee, Chancelloria sp., LinguleUa sp., Prototreta sp., Phakelodus tenuis (Miiller), Phakelodus elongates (An), Hertzina sp., and Furnishina sp. 展开更多
关键词 small shelly fossils (ssf) CONODONTS correlation Lower and Middle Cambrian Korea
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