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Chinese Science Bulletin 2001年第S1期46卷 6-11页

作者： YANG XiaopingInstitute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China (e-mail: xpyang@public2.east. ***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

A comparative study of geomorphologic landscapes in the Badain Jaran Desert and Taklamakan Desert was made on the basis of field investigations, thermolumi-niscence and radiocarbon dating as well as analysis of sand grain texture. The sand seas of the Badain Jaran Desert differ greatly from that of the Taklamakan Desert in terms of dune morphology, interdune relief, dune stratigraphy and sand sources. The thermoluminiscence ages of the dunes suggest that the basic configuration of the megadunes in the Badain Jaran Desert has not changed at least since Middle Holocene. There were periods of more humid environment during the last glaciation and Holocene in both deserts, but events of higher precipitation in the Badain Jaran Desert were more frequent than in the Taklamakan. In both desert areas, aeolian processes have been intensified during the last 2000 a.

关键词： desert sand seas palaeoclimate landscape northwestern China.

Biogeographical and palaeoclimate appraisal of mangrove vegetation in South Asia and Southeast Asia in the post Himalayan uplift scenario

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科学通报 2013年第S1期58卷 126-133页

作者： LIMAYE Ruta Bharat KUMARAN Krisnamenon Palghat Navnith Palynology and palaeoclimate Laboratory Palaeobiology GroupAgharkar Research Institute

Fossil evidence indicates that mangrove species have had their first appearance in the Late Cretaceous(70 65 Ma) and they have evolved around the Tethys seaway after the plate tectonics and the movement of the continents when Tethys Sea was fast closing as the massive continental fragments continued to shift and jostle across the globe. The oldest geological record of Acrostichum and Nypa palm offers good examples as these species prefer low-salinity requirements and have wide ecological tolerance. Such environmental and habitat preferences must have been the probable reason for their initial adaptation to mangrove habitat and a wider distribution. The open sea link must have also provided enough coastal areas for the establishment of mangrove ecosystem and subsequent spreading of the mangroves into newer areas by Early to Middle Eocene(ca 50–40 Ma). However, the mangroves started acquiring the present geographical positions towards OligoceneMiddle Miocene period. The fossil record and the modern analogues of Kandelia, Nypa and Pelliciera indicate that their biogeographical preferences have been shifted due to oceanic reorganization wherein the latter is now confined only to Atlantic East Pacific mangrove realm despite it was earlier widespread in the Tethys Sea. Although Rhizophora and Avicennia differ only at the species level and common occurrence of Acrostichum aureum, the present mangrove distribution shows the contrast in the biogeography of many genera due to geomorphic barriers and climatic changes. The Himalayan uplift and establishment of Asian summer monsoon system towards Late Neogene has also affected the coastal dynamics considerably which in turn modified the distribution of mangrove vegetation of the Indian subcontinent. The loss of sensitive habitats, disjunct distribution of a few species and local extinction of significant taxa has affected the overall biogeography of mangroves in South and SE Asia.

关键词： Palaeomangroves modern analogues biogeography palaeoclimate South and Southeast Asia Himalayan uplift

RECONSTRUCTING HOLOCENE PALAEORUNOFF REGIMES FROM palaeoclimate: AN INITIAL ATTEMPT TO APPLY A CLIMATOLOGICAL APPROACH TO PALAEOHYDROLOGY FOR THE NORTH CHINA PLAIN

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Chinese Geographical Science 1999年第3期9卷 58-65页

作者：王红亚

Employing the regression equations relating mean annual runoff to mean annual temperature and mean annual precipitation derived with modern data, palaeorunoff values were calculated from palaeoclimatic information for three localities in the eastern part of the North China Plain (37-41°N, 115-120°E) during the last 12 000 years. These results present a general pattern of temporal and spatial variations of the Holocene palaeorunoff occurring in this region. The annual runoff was the highest during 8000-3000 a B.P., the second high during 12 000-8000 a B.P., and the lowest during 3000-0 a B.P. Spatially the annual runoff was the highest at the downstream area of the Luanhe River in the north, the second highest at the area around Beijing in the middle, and the lowest at the area around Xingtai in the southwest. These results were further compared to other palaeohydrological reconstruction achieved by other researchers or with other methods, which usually indicates the similar trend of hydrological changes for this region.

关键词： palaeorunoff palaeoclimate palaeohydrology the North China Plain

The influence of organic sources and environments on source rock deposition during the periods of Cretaceous–Eocene and Oligocene–Miocene,northern Kalimantan

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Acta Oceanologica Sinica 2023年第3期42卷 54-64页

作者： Lei Lan Youchuan Li Zhigang Zhao Shuchun Yang Qing Lin Weilai Zhang China National Offshore Oil Corporation(CNOOC)Research Institute Co. Ltd.Beijing 100028China State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and Environment China University of PetroleumBeijing 102249China

The sedimentary system of Kalimantan has undergone significant development since the Oligocene.Previous research have largely ignored the capacity of the Cretaceous–Eocene sediments to produce hydrocarbons,focusing instead primarily on the Oligocene–Miocene coal as the principal source rocks.Shales and coals from the outcrops in the northern margin of Kalimantan were analyzed with palynological and geochemical methods to characterize the palaeoenvironmental and palaeoecological differences between the Cretaceous–Eocene and the Oligocene–Miocene samples.The high proportion of Cheirolepidoaceae,Schizaeoisporites and Ephedripites in the pollen assemblage from the Cretaceous–Eocene outcrops reflects an arid tropical/subtropical climate.The relatively low abundances of gymnosperm-derived biomarkers including isopimarane,β-phyllocladane,β-kaurane,suggest the gymnosperm features in flora.High C_(27)/C_(29)ααα20R sterane ratios,(C_(19)–C_(29))tricyclic terpanes/C_(30)αβhopane and extremely low oleanane/C_(30)αβhopane,bicadinane T/C_(30)αβhopane,and diterpenoid abundance indicate that there was a dominance of algae relative to higher plants in the organic matter.The gymnosperm-derived biomarkers,including isopimarane,β-phyllocladane,β-kaurane,suggest that palaeovegetation during this period was dominated by gymnosperms.The saline and reducing conditions in the bathyal and abysmal sea,evidenced by rather low Pr/Ph and high Gammarerane index,are beneficial for the preservation of hydrogen-rich organic matter.It is presumed that the Cretaceous–Eocene shales had great hydrocarbon generation potential in the southern South China Sea.During the period of Oligocene to Miocene in the Zengmu Basin and the Baram-Sabah Basin,the climate changed to a dominant humid and warm condition,which is corroborated by abundant pollen of Florschuetzia and Magnastriatites hawardi.Low C_(27)/C_(29)ααα20R sterane ratios,(C_(19)–C_(29))tricyclic terpanes/C_(30)αβhopane,and high oleanane/C_(30)αβhopane,bicadinane T/C_(30)αβhopane suggest that the pa

关键词： biomarkers source rocks palynological records palaeoclimate South China Sea

Clay mineral formation and transformation in non-marine environments and implications for Early Cretaceous palaeoclimatic evolution:The Weald Basin,Southeast England

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Journal of Palaeogeography 2022年第3期11卷 387-409页

作者： Oladapo O.Akinlotan Ogechukwu A.Moghalu Stuart J.Hatter Sunday Okunuwadje Lorna Anquilano Uche Onwukwe Safiyeh Haghani Okwudiri A.Anyiam Byami A.Jolly Department of Geography University of SussexFalmerBrightonBN19SJUnited Kingdom Department of Geology University of NigeriaNsukka Road410001NsukkaNigeria Badley Ashton and Associates Ltd Winceby HouseWincebyHorncastleLincolnshireLN96PBUnited Kingdom Department of Geology and Geophysics School of GeosciencesKings’CollegeUniversity of AberdeenScotlandAB243UEUnited Kingdom Experimental Techniques Centre Brunel University LondonBragg 16Brunel University LondonUxbridgeUB83PHUnited Kingdom Department of Geology Ahmadu Bello UniversityZariaNigeria

Analyses of clay minerals within the Early Cretaceous Weald Basin,Southeast England reveal kaolinite,illite and chlorite as the main detrital clay minerals while glauconite and smectite are subordinates.A kaolinite-rich assemblage which characterized the sand-dominated Ashdown and Tunbridge Wells Sand formations and an illite-dominated assemblage associated mostly with the Wadhurst Clay and Weald Clay formations are recognized.Kaolinite was enriched in the Ashdown and Tunbridge Wells Sand formations during warm and humid climate with high precipitation that encouraged chemical weathering and leaching,while cold and dry conditions favoured the concentration of illite in the Wadhurst Clay and Weald Clay formations.Rainfall patterns associated with warm climate were drastically reduced during the drier climatic conditions.Most clay minerals are detrital in origin,with chlorite being more prominent than previously recognized.Contrary to previous studies and assumptions,this study revealed that authigenic clay minerals are present in the Hastings Beds,with vermiform and mica-replacive kaolinite being the most common,consistent with humid depositional environments.Isolated authigenic illite is also present,along with a chloritized grain,providing evidence for mesodiagenesis.The absence of dickite and occurrence of kaolinite,suggest that authigenic illite formed in relatively shallow burial conditions,indicating a maximum burial depth of2500 m-3000 m,about 1000 m deeper than previous estimates of 1500 m-2000 m.Authigenic clay minerals are absent in the Weald Clay Formation possibly because of hindered flow of meteoric water and limited growth space for authigenic minerals.This study is significant in:1)reinforcing multiple methods to facilitate a robust and balanced knowledge of formation and transformation of clay minerals;2)investigating detrital and authigenic clay mineral assemblages when assessing the palaeoenvironments of sedimentary basins.

关键词： Clay minerals Clay mineral transformation palaeoclimate Early Cretaceous Weald Basin Wealden Southeast England

Climate characteristics of the eastern Mongolian Plateau,China during the early Early Cretaceous(145-132 Ma):Palynological evidence from the Tongbomiao Formation in Well Hong-6,Hailar Basin

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China Geology 2022年第3期5卷 439-456页

作者： Yan Zhang Yun-fei Xue Chun-yang Bu Ti Li Xin Zhang Yu-dong Jin Yue-wu Sun College of Earth Sciences Jilin UniversityChangchun 130061China Geological Laboratory Exploration and Development Research Institute of Daqing Oilfield Company Ltd.Daqing 163712China Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026China

This study identified two palynological assemblages,namely Bayanhuasporites-Cycadopites-Protoconiferus and Cicatricosisporites-Cedripites-Perinopollenites,in the Tongbomiao Formation in the Hongqi Sag in the Hailar Basin,Inner Mongolia,China for the first time.The former is distributed in the lower part of the Tongbomiao Formation and is characterized by abundant gymnosperm pollen and diverse fern spores.Among them,the gymnosperm pollen is dominated by Paleoconifer(4.98%-31.62%)and Cycadopite(8.55%-25.23%)pollen grains and also includes other pollen grains such as Classopollis,Parcisporites,Erlianpollis,Callialasporites,and Jiaohepollis.The fern spores in the former palynological assemblage contain Bayanhuasporite(0-8.96%),Granulatisporites(0.93%-6.97%),and some important Cretaceous genera,such as Cicatricosisporites,Concavissimisporites,Densoisporites,Hsuisporites,Foraminisporis,and Leptolepidites.The Cicatricosisporites-Cedripites-Perinopollenites palynological assemblage is distributed in the upper part of the Tongbomiao Formation.Gymnosperm(77.30%),Pinaceae(31.9%),and Paleoconiferus(19.02%)pollen predominate this palynological assemblage,and Quadraeculina,Erlianpollis,and Jiaohepollis pollen are also common in this assemblage.The fern spores in this palynological assemblage include abundant Cicatricosisporites(4.29%).Besides,Concavissimisporites,Aequitriradites,and Leptolepidites are also common in this palynological assemblage.No angiosperm pollen has been found in both palynological assemblages.The identification of both palynological assemblages provides important evidence for the biostratigraphic correlation between the Hailar Basin and its adjacent areas.It also enables the reconstructions of the Berriasian-Valanginian(Early Cretaceous)vegetation and the paleoclimate on the eastern Mongolian Plateau during 141-132 Ma.The vegetation reconstructed on the palynological data of the represented by Hailar Basin in eastern Mongolian Plateau(141.6-141.4 Ma),form conifer forest or conifer broad-leaved mixed fores

关键词： Tongbomiao Formation Palynological Assemblages Gymnosperm Berriasian-Valanginian Palaeovegetation palaeoclimate Hailar Basin Mongolian Plateau China

Palaeosol of the Siwalik Group as a 15 Ma Record of palaeoclimate

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地学前缘 2009年第S1期16卷 241-241页

作者： Ram Ratan Singh Centre of Advanced Study in Geology Panjab University

Palaeosols are one of the architectural elements of sedimentation in the Siwalik Foreland Basin holding a record of long term climate changes for the past 18 Ma.Systematic study of palaeosols,and associated non-pedogenic materials,along with their parent rock is important for understanding pedogenic processes and environments,which in turn gives insight into the interrelation between climate,topography and ecosystem.The fossil soils have a special value as they remains in the place of their formation

关键词： palaeosol Siwalik palaeoclimate

Early Miocene flora of central Kazakhstan(Turgai Plateau) and its paleoenvironmental implications

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Plant Diversity 2019年第3期41卷 183-197页

作者： Popova Svetlana Utescher Torsten Averyanova Anna Tarasevich Valentina Tropina Polina Xing Yaowu Komarov Botanical Institute of RAS Palaeobotanical Department 2 Professor Popov Str. Saint Petersburg 197376 Russia Steinmann Institute Bonn University Nussallee 8 Bonn D-53115 Germany Senckenberg Research Institute and Natural History Museum/Biodiversity and Climate Research Centre Senckenberganlage 25 Frankfurt D-60325 Germany Xishuangbanna Tropical Botanical Garden of Chinese Academy of Sciences (CAS) Menglum Mengla Yunnan 666303 China

The investigation of the fossil floras from the Turgai plateau (central Kazakhstan) contributes to a better understanding of the origin of the temperate Turgai type flora which spread to Kazakhstan and adjacent areas during the Oligocene-Miocene transition. In this paper, we present the results of a carpological and palynological study of the Kumyrtas flora collected from a flora-bearing horizon of the regional coalbearing Zhilanchik suite, dated to the Aquitanian period. Pollen analysis identified 33 taxa, with are dominated by angiosperms (about 73%) and reflect zonal vegetation. The high percentages of Betula (27%) and Pterocarya (7.5%) that were found in this flora allows comparisons with other Aquitanian floras of Kazakhstan. Based on descriptions of fossil fruits and seeds, we determined that 19 taxa were dominant;these taxa had meosphytic herbaceous components, suggesting mostly edaphic local conditions. The incongruence between the carpological and the pollen records suggests a significant taphonomical effect. Quantitative reconstruction of the palaeoclimate based on pollen records supports—and slightly extends—previous findings based on fossil leaf data, but contradicts findings deduced from the carpological record. Plant Functional Type (PFT) classification was used to characterize the vegetation patterns. Pollen records show that about 45% of diversity relates to the arboreal broadleaved deciduous components and ca. 35% to conifers. Fossil fruit and seed data indicate riverine vegetation with a high diversity of aquatic components and shrub stratum.

关键词： Kazakhstan Turgai flora Oligocenee-Miocene transition palaeoclimate reconstruction PFT

Cenozoic plant diversity of Yunnan： A review

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Plant Diversity 2016年第6期38卷 271-282页

作者： Yongjiang Huang Linbo Jia QiongWang Volker Mosbrugger Torsten Utescher Tao Su Zhekun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Mengla 666303 China Senckenberg Research Institute/BiK F (Loewe) Senckenberganlage 25 60325 Frankfurt am Main Germany State Key Laboratory of Paleobiology and Stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Steinmann Institute University of Bonn Nassallee 8 53115 Bonn Germany

Yunnan in southwestern China is renowned for its high plant diversity.To understand how this modern botanical richness formed,it is critical to investigate the past biodiversity throughout the geological time.In this review,we present a summary on plant diversity,floristics and climates in the Cenozoic of Yunnan and document their changes,by compiling published palaeobotanical sources.Our review demonstrates that thus far a total of 386 fossil species of ferns,gymnosperms and angiosperms belonging to 170 genera within 66 families have been reported from the Cenozoic,particularly the Neogene,of Yunnan.Angiosperms display the highest richness represented by 353 species grouped into 155 genera within 60 families,with Fagaceae,Fabaceae,Lauraceae and Juglandaceae being the most diversified.Most of the families and genera recorded as fossils still occur in Yunnan,but seven genera have disappeared,including Berryophyllum,Cedrelospermum,Cedrus,Palaeocarya,Podocarpium,Sequoia and Wataria.The regional extinction of these genera is commonly referred to an aridification of the dry season associated with Asian monsoon development.Floristic analyses indicate that in the late Miocene,Yunnan had three floristic regions:a northern subtropical floristic region in the northeast,a subtropical floristic region in the east,and a tropical floristic region in the southwest.In the late Pliocene,Yunnan saw two kinds of floristic regions:a subalpine floristic region in the northwest,and two subtropical floristic regions separately in the southwest and the eastern center.These floristic concepts are verified by results from our areal type analyses which suggest that in the Miocene southwestern Yunnan supported the most Pantropic elements,while in the Pliocene southwestern Yunnan had abundant Tropical Asia(Indo e Malaysia)type and East Asia and North America disjunct type that were absent from northwestern Yunnan.From the late Miocene to late Pliocene through to the present,floristic composition and vegetation types changed markedly,presumab

关键词： Cenozoic Fossil plants Floristic change Palaeobiodiversity palaeoclimate Yunnan

Palaeorunoff estimations achieved from palaeoclimatic information for the southwest part of the North China Plain: an attempt to apply a climatological approach to palaeohydrology

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Journal of Environmental Sciences 2000年第3期12卷 330-336页

作者： WANG Hong\|ya, XIE Qiang (Department of Urban and Environmental Sciences, Peking University,Beijing 100871, China) 北京大学北京 1 0 0 871

Palaeoclimatic scenario projecting annual temperature and annual precipitation is firstly formalized with data available and speculations for the southwest part of the North China Plain (35— 37°N, 115—119°E) during the last 25000 years. Then, with three regression equations relating annual runoff to annual precipitation and derived with data of modern hydrological and meteorological records, values of annual runoff are calculated in terms of the corresponding values of annual precipitation from this palaeoclimatic scenario for this region during this temporal interval. These results indicate that runoff is the most during 8000—3000 a B.P. and the least during 25000—12000 a B.P.; runoff occurring during 12000—8000 a B.P. and during 3000—0 a B.P. is less than the one occurring during 8000—3000 a B.P. and more than the one occurring during 25000—12000 a B.P.; and the runoff occurring during 25000—12000 a B.P., 12000—8000 a B.P., and 3000—0 a B.P. is respectively 43, 46 and 66 percent of the one occurring during 8000—3000 a B.P. Values of bankfull discharge for palaeochannels of the Yellow River flowing in this region during the same interval are calculated from available estimates of slope of stream bed of these palaeochannels with a regression equation relating bankfull discharge to slope of stream bed and ratios of bankfull discharge are further calculated from these values for different groups of palaeochannel formed during different time spans embraced in this interval. To conduct a cross check, these values and ratios of bankfull discharge are compared to the corresponding values and ratios of runoff occurring during roughly the same time spans. The same direction and similar relative magnitude of changes of the surface water occurring in this region during the last 25000 years are indicated by these comparisons.

关键词： palaeorunoff the southwest part of the North China Plain palaeoclimate