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The characteristic and evolution of coal-forming swamp in Hanshuiquan district,Santanghu Coalfield, Xinjiang,NW China,during the Middle Jurassic: evidence from coal petrography,coal facies and sporopollen

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International Journal of Coal Science & Technology 2019年第1期6卷 1-14页

作者： Shuo Feng Jing He Jijun Tian Xingyu Lu Bo Yang Institute of Geology and Mining Engineering Urumqi 830002Xinjiang China

Santanghu Coalfield is the largest integrated coalfield exploration area in China. The major coal seams developing in Xishanyao Formation (Middle Jurassic) are the high-quality steam coals characterized by large thickness, favorable horizontal continuity and high coal quality. In this paper, twenty-two samples were collected from the three typical boreholes in Hanshuiquan disirict, representing the 11 coal seam sequences (7#,8#,9#,13#, 14#,15#,17#,18#,19#,20#,22#), respectively. The petrographic characteristics of the coal-bearing sequence in Xishanyao Formation were firstly summarized systematicly, and then the coal-forming swamp characteristics and succession mechanism of the coal seam in Xishanyao Formation were defined by analyzing the samples. The maceral composition, structure, geochemical and geophysical characteristics of coal are in eluded in original genetic criteria of coal-forming swamp an alysis. And the composition of coal petrography, maceral and microlithotype are the most frequently used parameters. Coal is composed of microscopic constituents and inorganic substances. The Xishanyao Formation maceral mainly consists of vitrinite (65.74%-97.01 %), inert i nite (1.93%-34%), and the exinite shows the mode of regular change. The coal-forming swamp in Xishanyao Formation possesses the characteristics of mainly marsh, wet forest swamp facies, and shallow water covered forest swamp facies, and a few of coal seams distribute in the deep water covered forest swamp facies. In addition, the sporopollens in Xishanyao Formation are mainly Pinaceae evergreen broad leaf and needle-leaved plants. Osmundaceae, Cyatheaceae and Lygodiaceae, indicating that the warm and humid tropic-subtropical climate conductive to the persistent growth of coal-forming plants in the Middle Jurassic. The coal-forming swamp shows the characteristics of vertically upward fluctuation through the periodic transition. It indicates a shallow-deep-shallow change process of the water covered d

关键词： Santanghu Coalfield Xishanyao Formation Coal-forming swamp sporopollen

GEOLOGICAL SIGNIFICANT OF sporopollen ASSEMBLAGE IN THE XUESHAN FORMATION

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地学前缘 2000年第S1期7卷 151-151页

作者： Shi He,Wang Chengshan, Ma Runze,Wei Xiangui,Li Xianghui,Li Yong(Chengdu Institute of Technology, Chengdu 610059, China)

The Xueshan Formation is a set of red coarse clastic deposit of land facies consisting mainly of lithic sandstone, pebbled sandstone, conglomerate, intercalated with siltstone and mudstone. It is distributed in the eastern part of north Qiangtang Basin, and overlies conformably the Suowa Formation bearing marine fossils. It is very difficult to find valuable fossils from the Xueshan Formation excepting rare bivalve fragments and *** collected a few spore and pollen samples from the middle part of the Xueshan Formation in Tuonamulematianbao section, Shuanghu, in 1997, when we made geological survey for petroleum and nature gas. Some fossils of spore and pollen were obtained from these samples. They are: Cyathidites minor, Toroisporis sp .., Todisporites minor, Lygodiumsporites subsimplex, Cicatricosisporites ludbrooki, C. sp ., Psophosphaera sp ., Chasmatosporites minor, Classopollis annulatus, C. clssoiddes, C. minor, Cerebrropollenites carlylensis, Callialasporites dampieri, Quadraeculina anellaeformis, Pseudopicea variabiliformis.

关键词： Northern Qiangtang Xueshan Formation sporopollen assemblage diachronous Oxfordian uplifting

The depositional Environment at Shuidonggou Locality 2 in Northwest China at ～72-18 kaBP

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1539-1546页

作者： LIU Decheng GAO Xing LIU Enfa PEI Shuwen CHEN Fuyou ZHANG Shuqin Institute of Vertebrate Paleontology and Paleoanthtopology the Laboratory of Human EvolutionChinese Academy of Sciences The Fourth Geological Exploration Institute of Henan Geology and Mineral Bureau Research Center of Paleontology&Stratigraphy Jilin University

Shuidonggou site has abundant Paleolithic remains of Late Pleistocene deposition. Studying the evolution of depositional environments is essential to the comprehensive understanding of the living conditions of ancient populations. To reconstruct the depositional environment at Shuidonggou, we carried out archaeological excavations and collected systematic deposition samples at the key position of Shuidonggou Locality 2 for grain size analysis and sporopollen statistics. The environmental evolution around the Shuidonggou site generally underwent four stages at ~72-18 kaBP. During the first stage （~72-41 kaBP）, the river developed with gravel and sand stratums. During the second stage （41-34 kaBP）, a swamp with numerous aquatic plants formed. In the third stage （34-29 kaBP）, site formation was characterized by shallow lake depositional conditions; the climate was relatively warm and humid. The marginal bank depositional conditions deteriorated during the fourth stage （29-18 kaBP）, and the site underwent several dry events; the climate also became drier and colder.

关键词： Shuidonggou site depositional environment grain size sporopollen Upper Paleolithic

Evolution of vegetation and climate since the last glacial maximum recorded at Dahu peat site, South China

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Science China Earth Sciences 2007年第8期50卷 1209-1217页

作者： XIAO JiaYi Lü HaiBo ZHOU WeiJian ZHAO ZhiJun HAO RuiHui Department of Geographical Science Nanjing Normal UniversityNanjing 210046China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China Department of History and Civilization Weinan Normal UniversityWeinan 714000China

sporopollen analysis on a 346 cm peat record at Dahu, Jiangxi, chronologically constrained by 16 AMS 14C datings, provides an opportunity to reconstruct the vegetation evolution stages responding to cli-mate change in South China since the last glacial maximum. The result shows that during 18330-15630 cal a B.P., broad-leaved forest dominated the area, corresponding to mild, cool and fairly humid climate. At the interval of 15630-11600 cal a B.P., several evergreen broad-leaved species appeared within the broad-leaved forest, indicating moderate and humid condition. During early Holocene, broad-leaved evergreen forest community was constructed as Castanopsis/Lithorcarpus principally developed, suggesting a warm and humid scenario until 6000 cal a B. P. Since 6000 cal a B. P., abrupt forest deterioration happened with an contemporary increase of fern and herb communities, repre-senting a turnover to relatively cool and dry condition and as well, possible impact from human activi-ties. Meanwhile, several relatively cool and dry events can be identified in the sporopollen record, they can be correlated to the North Atlantic Heinrich event, YD and Holocene millennial-scale oscillations, implying that the low latitude climate was coupled with high latitude influences. Moreover, the varia-tions of temperature and humidity since LGM at Dahu were much smaller when compared with the re-cords in north monsoonal China.

关键词： peat site sporopollen analysis paleovegetation paleoenvironment

Quaternary Climate and Environment in the Lop Nur,Xinjiang

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 273-278页

作者： WANG Mill PU Qingyu LIU Chenglin CHEN Yongzhi Geological Society of China 26 Baiwanzhuang Rd.Beijing 100037 Institute of Mineral Deposits Chinese Academy of Geological Sciences26 Baiwanzhuang Rd.Beijing 100037

Since the middle Early Pleistocene (1.20 Ma B.P.), the desert steppe climate and environment have predominated in the Lop Nur area, Xinjiang, characterized by warm humid epochs interrupted by dry cold intervals. The grain-size and magnetic susceptibility curves record 30 climatic oscillations, each with a ca. 40 ka cycle, in the area since 1.2 Ma B.P., which reflects the controlling effects exerted by the astronomic factor on the environment. The Quaternary sedimentary environment in the Lop Nur gradually changed from a fresh lake through a brackish lake to a saline lake, showing a spiral evolution, and finally it evolved into a playa.

关键词： Lop Nur Quaternary palaeoclimate sedimentary environment sporopollen

Development background of Mesozoic high-quality source rocks: Evidence from microfossils in North Carnarvon Basin, Australia

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Petroleum Research 2019年第1期4卷 71-83页

作者： Xing Niu Xianghua Yang Detian Yan Xinguo Zhuang Bo Wang Shenjun Huo Xiaoming Xu Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education China University of Geosciences430074WuhanHubei ProvinceChina Faculty of Earth Resources China University of Geosciences430074WuhanHubei ProvinceChina CNOOC Research Institute Company Limited Beijing100028China

Based on numerous microfossils in Mesozoic of North Carnarvon Basin in Australia,the Mesozoic paleoclimate and paleoenvironment were analyzed,the paleogeographic background and development model of Mesozoic high-quality source rocks were investigated and *** of microfossil species and their relative contents in Mesozoic different intervals indicates changes of paleoclimate and *** paleoclimate shows a cycle variation of aridehumidearidehumid,the regression occurred in the Early TriassiceLate Triassic and the transgression occurred in the Late TriassiceLate *** sedimentary facieses including delta facies,littoral facies,restricted sea facies and open sea facies were developed in the *** open sea was mainly developed in the Early Triassic,the delta was distributed in the MiddleeLate Triassic,the restricted sea was especially well developed in the Jurassic,and the restricted sea and open sea were mainly distributed in the *** of microfossil assemblage in these four sedimentary facies are dramatically *** the delta facies,littoral facies,restricted sea facies to open sea facies,content of pollen gradually decreases,but content of the dinoflagellate+acritarch gradually *** delta facies and littoral facies are dominated by the *** the restricted sea facies,content of the pollen is equivalent to that of the dinoflagellate+*** open sea facies is dominated by the dinoflagellate and *** of sediment and formation of organic matter are influenced by the paleoclimate and paleoenvironment,and type of organic matter is controlled by the microfossil *** on the palaeogeographic background,paleoclimatic condition and microfossil assemblage,two developmental models of the Mesozoic source rocks such as the development model of terrestrial organic matter under the background of large delta and the development model of mixed organic matter under the

关键词： Microfossil assemblage sporopollen Dinoflagellate and acritarchs Paleoclimate reconstruction Evolution of sedimentary environment Development model of source rocks Mesozoic North Carnarvon basin

Palynomorphs in the first paleosol layer in the Yangtze Delta and their paleoenvi-ronmental implication

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Chinese Science Bulletin 2002年第21期47卷 1837-1841页

作者： WU Guoxuan QIN Jungan DENG Bing LI Congxian Key Laboratory of Marine Geology Ministry of EducationTongji UniversityShanghai 200092China

The relatively abundant palynomorphs were recovered from the samples of the first paleosol layer of core CY in Shanghai for the first time. A total of 55 genera and families of spore, pollen and phytoplankton were identified. According to the characteristics of the palynological assemblages, the depositional conditions in the development period of the paleosols were discussed and the microfossil evidence to study the origin of the paleosols in the Yangtze Delta area was provided as well. The research results show that paleosols should be freshwater deposits. The palynological assemblage sequence in the first paleosol layer reveals fluctuations of freshwater palynomorphs, mainly Concentricystis, and terricolous herbs pollen, reflecting the alternations of deposition and exposure in the development period of the paleosols. Concentricystis developed prosperously in the period of flood, while terricolous herbs grew on the emerged land in the period of exposure. The variations in the palynological

关键词： Yangtze Delta paleosol layer sporopollen phytoplankton paleoenvironment.

Discovery of the earliest Triassic spores and pollen from southwest Tarim and Permian-Triassic (P-T) boundary

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Chinese Science Bulletin 1996年第24期41卷 2066-2069页

作者：朱怀诚 Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

There is a suit of well-developed terrestrial deposits with great thickness in the Pishanand Hotan areas,southwest Tarim *** age determination and stratigraphicalcorrelation have been argued for many *** strata were called Yarkant System andassigned to the Upper Permian through Lower-Middle Jurassic based on the fossil plantsbefore the *** 1962,Sze et al. renamed it the Yarkant Group to

关键词： sporopollen assemblage Duwa Formation P-T boundary southwest Tarim.

Discrimination of depositional seasonality of tidal flat sediment in northern Jiangsu Province,China

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Chinese Science Bulletin 2001年第S1期46卷 104-107页

作者： WANG Jian, HUANG Qiaohua, XIAO Jiayi, BAI Chunguang, ZHU Xiaohua & CHEN XiaCollege of Geographical Sciences, Nanjing Normal University, Nanjing 210097, China College of Geographical Sciences Nanjing Normal University Nanjing 210097 China

12 consecutive monthly sediment samples were collected from the tidal flat surface in Dafeng County, Jiangsu province. Palynological analysis of these samples indicates that seasonal palynological features of the tidal flat sediment are distinct and some palynological indices such asspecies percentages of Arboreal and Herbaceous pollen and spore are good indicators for discriminating the depositional seasonality of the tidal flat sediment. Sedimentary sequences formed between 1984 and 1994 were used to verify this method. The result proposes that this method can be applied to muddy flat and the species percentage of arboreal pollen is the best indicator for the seasonality study of the tidal flat sediment.

关键词： seasonal deposition tidal flat sporopollen Jiangsu Province.