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palynology and stratigraphy of the Upper Miocene Chad Formation, Bornu Basin,northeastern Nigeria

Journal of Palaeogeography 2017年第2期6卷 108-116页

作者： A. Olatunji Ola-Buraimo Yunusa Abdulganiyu Department of Geology Federal University Bimin Kebbi Bimin Kebbi Nigeria

Both lithological and palynological analyses were employed to decipher sedimentary stacking patterns and to date the sediments within the interval 50—325 m in Kemar-1 well,Bornu Basin,northeastern *** different lithofacies units deposited in various environments were *** are:(1) the grayish sandy claystone,rich in organic matter and associated with lignite,deposited in a continental to lacustrine environment;(2) the micaceous claystone,rich in muscovite flakes and organic matter,deposited in a lacustrine environment;(3) the lithified claystone which intercalates the dark gray shale,and deposited in a marine setting;(4) the shale;(5) the micaceous sandstone,which is characterized by presence of muscovite,silty to granular grain sizes,well sorted and deposited in a meandering setting;(6) the poorly-sorted *** is poorly sorted,poorly-graded,and coarse-grained,with erosive surfaces to underlying facies,and deposited in a fluvial environment;(7) the heterolithic clayey sandstone,poorly graded,grayish,with a degree of organic richness,suggesting an anoxic lacustrine environment;and(8) the grayish claystone which is nonlithic and rarely ferruginized marking the Upper Miocene/Eocene *** main palynological zone,i.e.,the Echitricolporites spinosus assemblage zone,has been *** base of the studied section at 385 m is characterized by the last up-hole occurrence of Grimsdalea magnaclavata suggestive of Eocene boundary while the overlying sediments are characterized by Late Miocene marker species such as ***,Elaeis guineensis,Anthocerus sp.,Nymphaea lotus,and *** *** Chad Formation is dated as Late Miocene age unconformably overlying the Eocene Kerri-Kerri Formation which indicated that the Chad Formation was probably deposited during an alternation of lacustrine and continental settings,due to climatic change.

关键词： palynology Lacustrine Continental Late Miocene Heterolithic Unconformity Bornu Basin Northeastern Nigeria

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palynology and stratigraphy of the thick evaporate-bearing Shashi Formation in Jiangling Depression,Jianghan Basin of South China,and its paleoclimate change

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China Geology 2020年第2期3卷 283-291页

作者： Chun-lian Wang Cheng-lin Liu Jiu-yi Wang Xiao-can Yu Kai Yan Ministry of Natural Resources Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China

In the greater inland Jianghan Basin of South China,three salt depressions are lacking accurate geological times,of which Jiangling Depression is the *** are important records of paleoclimate,however,the geological ages of evaporates are very difficult to be determined because often evaporates have scare macrofossils and *** Cretaceous to Tertiary halite deposits interbedded with mudstones are widely distributed in ***-Eocene Thermal Maximum had very high temperatures and attracted strong interests of geologists because these times can be compared with future climate change because of global ***,previous studies focused on marine sediments found that during the Paleocene-Early Eocene,massive evaporate deposits formed in Jiangling depression of the Jianghan *** this paper,the authors show that the Shashi Formation halite deposits formed in the Paleocene according to *** of these palynology fossils are arid types,so the massive evaporites in the Jiangling depression could be closely related to the hot Paleocene *** temperatures during the Paleocene contributed to the formation of the massive evaporates in the Jiangling Depression,until sylvite was the result.

关键词： palynology Geological age of evaporate Sylvite Paleocene Paleoclimate Shashi Formation Mineral exploration engineering South China

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Progress, problems and prospects of palynology in reconstructing environmental change in inland arid areas of Asia

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Research in Cold and Arid Regions 2021年第4期13卷 271-291页

作者： YongTao Zhao YunFa Miao Yan Lei XianYong Cao MingXing Xiang Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Studying the climatic and environmental changes on different time scales in inland arid regions of Asia can greatly im‐prove our understanding of climatic influences for the Qinghai-Tibet Plateau in the context of global change. Pollen, as a remnant of seed plants, is sensitive to environmental factors including precipitation, temperature and altitude, and is a clas‐sic proxy in environmental reconstruction. In the last two decades, great progress in the application of palynology to in‐land areas of Asia has highlighted the role of palynology in paleoclimatic and paleoenvironmental research. The main progress is as follows. (1) On the tectonic time scale of the late Cenozoic, the palaeoclimatological sequence has been es‐tablished on the basis of pollen percentage, concentration and taxon. Pollen data have revealed a continuous enhancement of drought in the inland arid region of Asia, in contrast to evidence acquired based on other proxies. (2) In the late Quater‐nary, an increase in herbaceous plants further supports the intensification of drought associated with global cooling. In more detail, the palynological record shows a glacial-interglacial pattern consistent with changes in global ice volume. (3) The Holocene pollen record has been established at a high resolution and across a wide range of inland areas. In general, it presents an arid grassland environment in the early Holocene, followed by the development of woody plants in the mid- to late-Holocene climate optimum. This pattern is related to moisture changes in areas dominated by the westerlies. There are also significant regional differences in the pattern and amplitude of vegetation response to the Holocene environment. (4) Modern pollen studies based on vegetation surveys, meteorological data and statistics show that topsoil palynology can better reflect regional vegetation types (e. g., grassland, meadow, desert). Drier climates yield higher pollen contents of drought-tolerant plants such as Chenopod

关键词： palynology inland arid areas Late Cenozoic Quaternary Holocene modern environmental processes

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palynology AND ORGANIC CARBON ISOTOPES TO ELUCIDATE THE MILLENNIAL SCALE EVOLUTION OF A MIDDLE DEVONIAN LAKE IN RESPONSE TO CLIMATE CHANGE, ORCADIAN BASIN, SCOTLAND

PALYNOLOGY AND ORGANIC CARBON ISOTOPES TO ELUCIDATE THE MILL...

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第二届国际古生物学大会

作者： M.H.STEPHENSON U.MICHIE C.H.VANE British Geological Survey KeyworthNottingham NG12 5GGUK 21 Dunster Road West Bridgford NG26JF UK

There are few palaeolimnological studies of Palaeozoic lake sediments using methodologies developed for the study of Quaternary lakes. New research described here indicates the benefits of applying multidisciplinary high-resolution sampling and analysis on the Middle Devonian lake sediments of the Orcadian Basin in order to understand lake palaeoecology and response to water chemistry change and possible climate change. In a continuously sampled 4 m thick lake cycle in two correlated boreholes in Caithness there are two distinct features. There is a broad trend in δ13C of sedimentary organic matter from high values in the shallow water sediments to lower values in the deeper water sediments, attributed to changing contributions from terrestrial plant material (δ13C c. -28‰) and algal material (δ13C c. -33‰). This variation is consistent with palynology and is best explained by proximal-distal varia-

关键词： palynology isotopes Devonian palaeolimnology

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palynology in tropical northern Australia: Identifying late Holocene vegetation change in the South Wellesley Islands

Palynology in tropical northern Australia: Identifying late ...

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中国古生物学会孢粉学分会十届一次学术年会

作者： Lydia Mackenzie Patrick Moss Sean Ulm State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences School of Earth and Environmental Science The University of Queensland College of Arts Society and Education James Cook University

This study presents a record of late Holocene environmental change from the South Wellesley Islands in tropical northern Australia. Fossil pollen records from coastal wetlands explored the relationship between humans and the environment, and results from this study provided an environmental context for archaeological research. Archaeological research in the South Wellesley Islands found human occupation occurred only in the last 1,500 years, with sites increasing significantly in the last 700 years. Pollen records found initial changes in the vegetation across the island were driven by late Holocene sea-level regression and coastal progradation, as mangroves transitioning to woodland and wetland communities in the last 850 years. Macroscopic and microscopic charcoal complements the palynological research by identifying the spatial and temporal variation in fire regimes across the island. Results indicate low intensity fires characterised the early human occupation phase. Local and regional fires increased significantly around AD 1950 when Indigenous fire practices were disrupted and the South Wellesley Islands abandoned. In tropical northern Australia many plants are adapted to fire, however the palynological research found only small vegetation changes occurred as fire significantly increased. This study highlights the importance of using multi-proxy approaches to reconstructing past environments, especially where vegetation is adapted to fire.

关键词： palynology Northern Australia Late Holocene Coastal Vegetation change Fire

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palynology of the Early Cretaceous Hanxia Section in the Jiuquan Basin,Northwest China:The discovery of diverse early angiosperm pollen and paleoclimatic significance

Palynology of the Early Cretaceous Hanxia Section in the Jiu...

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中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Mingzhen Zhang Liming Ji Baoxia Du Shuang Dai Xuewen Hou Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources ResearchInstitute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Western China's Mineral Resources of Gansu Province MOE Key Laboratory of Western China's Environmental SystemsLanzhou University State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology

The Lower Cretaceous deposits of the Jiuquan Basin(Northwestern China)located in central Asia are famous for the abundant and diverse fossil products with distinct characteristics of Jehol ***,few early angiosperm remains have been published in their *** study presents a palynomorph record from the recently reported fossil-bearing Zhonggou Formation of the Hanxia Section in the Jiuquan ***,we first discovered abundant and diverse angiosperm pollen with 16 taxa,which can be classified into four morphological types:tricolpate,polyaperturate,monosulcate and etrachotomocolpate *** palynomorph assemblages contain a large number of biostratigraphically significant palynomorphs,such as numerically abundant tricolpate and rare polyaperturate angiosperm pollen grains,which indicate an Early Albian age for the Zhonggou Formation of the Hanxia *** overall palynomorph assemblage is dominated by the Perinopollenites,followed by the Classopollis;bisaccate pollen indicate Taxodiaceae-dominant vegetation *** such,a relatively temperate and humid climatic condition is suggested for this ***,two palynomorph assemblages can be distinguished in a stratigraphically upward order with an obviously increasing Classopollis content,indicating a gradual aridification trend during the Early *** climatic change may affect the diversification of early angiosperms based on the correlation with the stratigraphic distribution of discovered angiosperm pollen.

关键词： palynology Early angiosperm Albian Jiuquan Basin China

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Late Cretaceous-Paleogene Formation of the Bekrit Syncline, Middle Atlas, Morocco: Sedimentology, Geochemistry, palynology and Paleoenvironments

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Open Journal of Geology 2021年第3期11卷 61-80页

作者： Mohammed El Attmani Amine Bouwafoud Salem Elouariti Hicham Si Mhamdi Abdelmajid Ben Bouziane Mustapha Mouflih Sedimentary Basins Dynamic and Geological Correlations Laboratory Department of Geology Faculty of Science Ben M’sik Hassan II University of Casablanca Casablanca Morocco Laboratory of Applied Geology Department of Geosciences Faculty of Sciences and Techniques Errachidia Moulay Isma&#239 l University of Meknes Meknes Morocco

Globally, the Paleogene period experienced several events marking the Paleocene-Eocene transition which is especially to one of the hottest periods that the Earth has ever known (Paleocene-Eocene Thermal Maximum, PETM), followed by the biological crisis that affected benthic foraminifera. The Bekrit Syncline, subject of this study, shows three Formations of range from the Cretaceous to the Eocene ages (the El Koubbat, Irbzer and Bekrit-Timahdite Formations). Sedimentological, palynological and geochemical analyses of collected samples, in the Bekrit syncline, were studied to determine the paleogeographic and paleoenvironmental conditions of the Middle Atlas. The carbonate rocks were analyzed by microscopic study and geochemical analysis by X-ray Fluorescence (XF) and Inductively Coupled Plasma Spectrometry (ICP). The results obtained highlight the sedimentary events that took place during the Paleogene. Thus, the Maastrichtian is characterized by a closed euxinic marine environment shared by a more open and oxidizing environment. On the other hand, the Paleocene was a restricted marine environment with evaporitic sedimentation, while the Eocene sees the installation of a carbonate platform with a bioclastic Shoal.

关键词： Geochemistry Sedimentology palynology Carbonates Phosphate Paleoenvironments Middle-Atlas

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Environment and Age of the Upper Devonian‒Carboniferous Zhulumute and Hongguleleng Formations,Junggar Basin,NW China:Ichnological and Palynological Aspects

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 724-739页

作者： MichałS TACHACZ Marcelina KONDAS PawełFILIPIAK MA Xueping Institute of Geological Sciences Jagiellonian University in KrakówGronostajowa 3a30-387 KrakówPoland University of Silesia in Katowice Faculty of Natural SciencesBędzińska 6041-200 SosnowiecPoland School of Earth and Space Sciences Peking UniversityBeijing 100871China

Two Upper Devonian to Lower Carboniferous sections,namely the Bulongguoer and Haer(Gennaren area)in the Junggar Basin,Central Asian Orogenic Belt,in northwestern China were examined with regard to ichnology and *** deposits of the Hongguleleng Formation and Namu Member of the Heishantou Formation,respectively,are mostly unbioturbated or poorly bioturbated,with poorly diversified trace fossils,which indicate unfavourable conditions for the burrowing benthic community during the Late Devonian and Early *** main factor governing the growth of the bioturbating population was the rapid sedimentation of fine-grained,volcanic material documented as tempestites,which buried the benthic *** the Bulongguoer section,the presence of miospores Teichertospora torquata and Grandispora gracilis enabled identification of the broad Teichertospora torquata–Grandispora gracilis Miospore Zone from the transitional Frasnian/Famennian *** accurate identification of palynostratigraphical levels(DE and CZ Miospore zones)is only *** the basis of palynofacies analysis,samples from the lower Bulongguoer section indicate deposition in more proximal conditions,whereas samples from the top of the section indicate deposition in a more distal *** the Haer section,only a general biostratigraphic indication for the Tournaisian was possible,owing to poor preservation of organic matter.

关键词： trace fossils palynology event deposition Frasnian/Famennian/Tournaisian Xinjiang

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Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez Carmelo Gómez-Martínez MiguelÁngel Gonzalez-Estévez Amparo Lazaro Mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks

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Paleo-uplift forced regional sedimentary evolution:A case study of the Late Triassic in the southeastern Sichuan Basin,South China

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Petroleum 2024年第3期10卷 462-473页

作者： Fangyu He Qingsong Cheng Dongtao Zhang Yubing Ji Ziying Wang Tenghui Lu PetroChina Zhejiang Oilfield Company Hangzhou 310023China School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500China Sichuan Natural Gas Geology Key Laboratory Southwest Petroleum UniversityChengdu610500China

The sedimentary environment of the Upper Triassic in the southeastern Sichuan Basin is obviously controlled by Luzhou paleo-uplift(LPU).However,the influence of paleo-uplift on the sedimentary patterns of the initial stages of this period in the southeastern Sichuan Basin has not yet been clear,which has plagued oil and gas exploration and *** study shows that there is a marine sedimentary sequence,which is considered to be the first member of Xujiahe Formation(T_(3)X^(1))in the southeastern Sichuan *** development of LPU resulted in the sedimentary differences between the eastern and western Sichuan Basin recording T_(3)X^(1)and controlled the regional sedimentary *** western part is dominated by marine sediments,but the eastern paleo-uplift area is dominated by continental sedimentation in the early stage of T_(3)X^(1),and it begins to transform into a marine sedimentary environment consistent with the whole basin in the late stage of the period recorded by the Xujiahe *** evidences are as follows:(1)time series:based on the cyclostratigraphy analysis of Xindianzi section and Well D2,in the southeastern Sichuan Basin,the period of sedimentation of the Xujiahe Formation is about 5.9 Ma,which is basically consistent with the Qilixia section,eastern Sichuan basin,where the Xujiahe Formation is widely considered to be relatively complete;(2)distribution and evolution of palaeobiology:based on analysis of abundance evolution of major spore-pollen,many land plant fossils are preserved in the lower part of T_(3)X^(1),indicates the sedimentary environment of continental *** the upper part of T_(3)X^(1),the fossil of terrestrial plants decreased,while the fossil of marine and tidal environment appeared,this means that it was affected by the sea water in the late stages of T_(3)X^(1);(3)geochemistry:calculate the salinity of water from element indicates that the uplift area is continental sedimentary environment in the early stage

关键词： Luzhou paleo-uplift Late Triassic Cyclostratigraphy palynology Sedimentary environment

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