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An updated constraint on the local stratigraphy at the Chang'E-4 landing site

Earth and Planetary Physics 2021年第1期5卷 19-31页

作者： YiRen Chang ZhiYong Xiao YiChen Wang ChunYu Ding Jun Cui YuZhen Cai state {1. laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Planetary Environmental and Astrobiological Research laboratory School of Atmospheric SciencesSun Yat-sen UniversityZhuhaiGuangdong 519000China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230000China National Astronomical Observations of China Chinese Academy of SciencesBeijing 100000China

The Chang’E-4 mission has been exploring the lunar *** scientific targets of the rover onboard are(1.resolving the possible mineralogy related to the South Pole-Aitken basin and(2)understanding the subsurface processes at the lunar *** to date that are based on the reflectance spectra and radar data obtained by the rover have shown a persistent inconsistency about the local *** explain both the abnormal surface topography at the landing site and the unexpected radargram observed by the rover,the Alder crater has been frequently reported to be older than the mare basalts at that landing ***,this argument is not supported by earlier geological mapping nor recent crater *** this controversy is critical for a full understanding of the geological history of the landing area and for correct interpretations of the scientific data *** detailed crater statistics,rigorous statistical analyses,and an updated crater chronology function,this study is determined to resolve the relative ages of the Alder crater,Finsen crater,and the mare basalts on the floor of Von Kármá*** results reveal that while background secondaries and local resurfacing have widely occurred in the study area,affecting age determinations,the statistics are significant enough to conclude that the Alder crater is the oldest among the three *** independent constraint is consistent with both the crosscutting relationships of different terrains in this area and global stratigraphic *** results exclude Alder as a possible contributor of the post-mare deposits at the landing site,appealing for a more systematic stratigraphy study to resolve the provenances of these deposits.

关键词： Moon Chang'E-4 impact craters absolute model age stratigraphy

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Rb and Sr Geochemical Characterization of the Chinese Loess stratigraphy and Its Implications for Palaeomonsoon Climate

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 279-288页

作者： CHEN Jun WANG Yongjin CHEN Yang LIU Lianwen JI Junfeng LU Huayu Department of Earth Sciences Nanjing UniversityNanjing 210093 Department of Geography Nanjing Normal UniversityNanjing 210097 Department of Earth Sciences Nanjing UniversityNanjing 210093 Xi’an state {1. laboratory of Loess and Quaternary Geology Chinese Academy of SciencesXi’an 710061

Concentrations and distributions of Rb and Sr in loess and palaeosol samples from the Luochuan profile have been studied, in grain-size fractions and chemical forms. Results show that Rb is quite rich in the fraction of less than 2 μm, and exits only in the residual phase, while Sr is distributed in sand and silt fractions, occurring in the residual and carbonate phases. Therefore, variations of the concentrations of Rb and Sr in loess and palaeosols are closely related not only to dustfall compositions depending on winter monsoon wind strength but also to summer monsoon-induced pedogenic intensity. This indicates that variations of Rb/Sr ratio in Chinese loess sequences represent cyclic alternations of East Asian summer and winter monsoon climates on the orbital time-scale. Variations in Sr concentrations along the sequence bear a high similarity to the oxygen isotope record of the deep sea sediments over the past 2.5 Ma, whereas variations in Rb concentrations are in good agreement with the record of magnetic susceptibility determined with the duplicated samples from the same profile. This suggests that (1. the high-latitude ice volume is responsible for East Asian monsoon variations and (2) the signal of magnetic susceptibility depends dominantly on pedogenesis in Chinese loess sequences.

关键词： Rb and Sr geochemical characterization Rb/Sr ratios loess sequence palaeomonsoon climate Loess Plateau

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Carbonate Sequence stratigraphy of a Back-Arc Basin: A Case Study of the Qom Formation in the Kashan Area, Central Iran

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Acta Geologica Sinica(English Edition) 2007年第3期81卷 488-500页

作者： XU Guoqiang ZHANG Shaonan LI Zhongdong SONG Lailiang LIU Huimin state {1. laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Chengdu Sichuan 610059 Geological Research Institute ofShengli Oilfield Co. Ltd. Dongying Shandong 257015 Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640

The Qom Formation comprises Oligo-Miocene deposits from a marine succession distributed in the Central Basin of Iran. It is composed of five members designated as A-F. Little previous work exists on the sequence stratigraphy. Based on an integrated study of sequence stratigraphy with outcrop data, wells and regional seismic profiles, the Qom Formation is interpreted as a carbonate succession deposited in a *** back-arc basin. There are two second-order sequences （designated as SS1.and SS2） and five third-order sequences （designated as S1.S5）. Five distinct systems tracts including transgressive, highstand, forced regressive, slope margin and Iowstand have been recognized. The relationship between the sequences and lithologic sub-units has been collated and defined （S1.to S5 individually corresponding to A-C1. C2--C4, D-E, the lower and upper portions of F）; a relative sea level change curve and the sequence stratigraphic framework have been established and described in detail. The coincidence of relative sea level change between that of the determined back-arc basin and the world indicates that the sedimentary cycles of the Qom Formation are mainly controlled by eustatic cycles. The variable combination of the systems tracts and special tectonic-depositional setting causally underpin multiple sequence stratigraphic framework styles seen in the carbonates of the back-arc basin revealing：（1. a continental margin basin that developed some form of barrier, characterized by the development of multiple cycles of carbonate-evaporites; （2） a flat carbonate ramp, which occurred on the southern shelf formed by the lack of clastic supply from nearby magmatic islands plus mixed siliciclastics and carbonates that occurred on the northern shelf due to a sufficient clastics supply from the land; and （3） a forced regressive stratigraphic stacking pattern that occured on the southern shelf and in basin lows due to the uplifting of the southern shelf. Thick and widespread a

关键词： Iran Tertiary Qom Formation back-arc basin carbonate sequence stratigraphy

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The internal structure of Early Cambrian fossil embryo Olivooides revealed in the light of Synchrotron X-ray Tomographic Microscopy

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Chinese Science Bulletin 2008年第24期53卷 3860-3865页

作者： CHEN Fang1.2 & DONG XiPing1.2 1.School of Earth and Space Sciences,Peking University,Beijing 1.0871.China 2 laboratory of Paleontology and {1.,Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nan-jing 21.008,China School of Earth and Space Sciences Peking University Beijing 100871 China laboratory of Paleontology and {1. Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

Countless fossil embryo Olivooides and the hatched larvae,juveniles and adults(the latter two kinds are Punctatus) are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section,near Kuanchuanpu Village,Ningqiang County,Shaanxi Province,*** the technique of Synchrotron X-ray Tomographic Microscopy,the 3D internal structure of Olivooides and Punctatus is *** morphological and statistic analyses are also given to the stellae structure of Olivooides and Punctatus,which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching,probably with the function of mucilage *** internal structure of Punctatus is described and *** ovum-like structure,a common internal feature of Punctatus,is considered as the taphonomic structure,rather than eggs or other biological *** structure is thought to be formed after the burial of the animal and before or during the *** original internal structure of Punctatus is assumed to be tabulae-filled,with soft body grown on them.

关键词：同步加速器 X射线显微镜寒武系化石动物区系内部结构

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中生代锥叶蕨属(Coniopteris)分类位置的重新讨论（英文）

中生代锥叶蕨属(Coniopteris)分类位置的重新讨论（英文）

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中国古生物学会第十二次全国会员代表大会暨第29届学术年会

作者：李春香苗馨元张丽兵马俊业郝家胜杨群 state {1. laboratory of palaeobiology and stratigraphy NanjingInstitute of Geology and PalaeontologyChinese Academy of Sciences Center for Excellence in Life and Paleoenvironment Chinese Academy of Sciences University of Chinese Academy of Sciences Missouri Botanical Garden Chengdu Institute of Biology Chinese Academy of Sciences College of Life Sciences Anhui Normal University

The extinct fern genus Coniopteris Brongniart was a typical component in the Mesozoic flora with a wide distribution in both Northern and Southern Hemispheres from Early Jurassic to Early Cretaceous,and it played a very important role in indicating *** the very beginning of the discovery of Coniopteris,it was placed in the family Dicksoniaceae based on its cup-shaped indusia,resembling that of Thyrsopteris elegans in ***,*** has been moved from Dicksoniaceae to its own family Thyrsopteridaceae,leaving the systematic attribution of Coniopteris *** this study,we analyzed the data available to reevaluate the systematic position of *** major results include:1. All extant genera in Dicksoniaceae have bivalvate indusia,while species of Coniopteris have cup-shaped indusia;2) Most Dicksoniaceae occur in the tropical zone,different from the temperate habitats we thought for Coniopteris;3) Coniopteris is herbaceous,whereas extant Dicksoniaceae are mostly tree-like ferns;4) Dicksoniaceae and Thyrsopteridaceae all have oblique annuli,while most species of Coniopteris has vertical *** on these differences,Coniopteris should not be kept in Dicksoniaceae,its systematic position was further evaluated by a cladistic analysis of using morphological characters of spore-producing organs and spores together with a molecular phylogenetic tree as a constrain(molecular backbone).The results show that Coniopteris is clustered with Dennstaedtia,Lindsaea,and Odontosoria,not with Calochlaena,Dicksonia,Lophosoria in *** results lead us to propose that Coniopteris may be more closely related with Polypodiales than with Dicksoniaceae,and Coniopteris probably is one of stem groups of Polypodiales.

关键词： Mesozoic Coniopteris phylogeny molecular dating

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Sequence architecture and sedimentary characteristics of a Middle Jurassic incised valley,western Sichuan depression,China

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Petroleum Science 2018年第2期15卷 230-251页

作者： Jun-Long Liu Wei Yin You-Liang Ji Tian-Yun Wang Fu-Xiang Huang Hai-Yue Yu Wen-Shu Li Sinopec Exploration&Production Research Institute Beijing 100083China state {1. laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Xinxing Geophysical Department Bureau of Geophysical ProspectingCNPCZhuozhou 072751HebeiChina Daqing Oil Company CNPCDaqing 163000HeilongjiangChina

The Middle Jurassic Shaximiao Formation encompasses tens of meters of thick lowstand meandering valley （LMV） strata in the western Sichuan foreland basin. Ancient LMVs newly discovered in this area were further studied based on sequence stratigraphy and seismic sedimentology. The aim of the present study was to investigate the sedimentary characteristics, sequence architecture, and the controls on LMV deposition in this tectonically active basin using field survey data, seismic sections, seismic amplitude imaging, core description, and comprehensive application of drilling data. The results show the following：（1. Three regional sequence boundaries and two flooding surfaces were recognized, and the Shaximiao For- mation was divided into two-third-order sequences and four systems tracts. （2） Three sedimentary facies associations were identified： incised valley-fill, tributary channel, and overbank facies. Incised valleys are 5-1. km wide, 20-60 m deep and traceable for 1.0 km along their axes. （3） In the downstream segment, the role of tectonism gradually diminishes, and periodic base-level changes control the form and evolution of the incised valleys. Three types of LMVs--AI, A2, and A3--developed with changes in base level （lake level）; of these types, the base level of the A3 LMV was likely the lowest.

关键词： Sequence architecture Sedimentary characteristic Lowstand meandering valley Western Sichuandepression Shaximiao Formation

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The first theropod tracks from the Middle Jurassic of Gansu,Northwest China:new and rare evidence of quadrupedal progression in theropod dinosaurs

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Journal of Palaeogeography 2019年第2期8卷 198-208页

作者： Da-Qing Li Li-Da Xing Martin G.Lockley Anthony Romilio Jing-Tao Yang Long-Feng Li Institute of Vertebrate Paleontology and College of Life Science and Technology Gansu Agricultural University School of Earth Sciences and Resources China University of Geosciences(Beijing) state {1. laboratory of Biogeology and Environmental Geology China University of Geosciences(Beijing) Dinosaur Trackers Research Group University of Colorado Denver School of Biological Sciences The University of Queensland

A new Middle Jurassic tracksite dominated by non-avian theropod footprints from the Wangjiashan Formation in Pingchuan District,Baojishan Basin,Gansu Province has yielded a unique trackway with four consecutive manus-pes *** three previous examples,all Early Jurassic in age,of theropod trackways are known with convincing examples of manus tracks and in each case,only two tracks were recorded in association with pes tracks with metatarsal impressions and pelvic traces indicating crouching ***,this is the first example of manus tracks registered while a theropod trackmaker was *** unique configuration is here designated as Grallator pingchuanensis *** shows the trackmaker forelimbs registering in a wide straddle gait,much wider than the pes trackway *** confirms previous reports that theropods could occasionally register tridactyl,ectaxonic manus *** the case of the Pingchuan trackway,the short step indicates an animal moving at a slow speed,probably due to a soft substrate.

关键词： Wangjiashan Formation Grallatorid Grallator Theropods Dinosaur tracks

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Complete mitogenome of the Painted Jezebel,Delias hyparete Linnaeus(Lepidoptera:Pieridae)and its comparison with other butterfly species

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Zoological Research 2012年第6期33卷 111-120页

作者： Qinghui SHI Jing XIA Xiaoyan SUN Jiasheng HAO Qun YANG College of Life Sciences Anhui Normal UniversityWuhu 241000China Nanjing Institute of Paeleontology and stratigraphy the Chinese Academy of SciencesNanjing 210008China

In the present study,we report the first complete mitochondrial genome(mitogenome)of the Painted Jezebel,Delias *** mitogenome of Delias hyparete is 1.1.6 bp in length,and has typical sets of 37 genes:1. protein-coding genes(PCGs),2 ribosomal RNAs,22 transfer RNAs and a non-coding A+T-rich *** protein-coding genes are initiated by ATN codons,except for COI,which is tentatively designated by the CGA codon,as observed in other butterfly species.A total of 1. PCGs harbored the complete termination codon TAA or TAG,while the COI,COII and ND5 genes ended at a single T *** 22 tRNA genes show typical clover structures,with the exception of the tRNASer(AGN)which lacks the dihydrouridine(DHU)stem and is instead replaced by a simple *** intergenic spacers totaling 1.3 bp,and 1. overlapping regions totaling 46 bp are scattered throughout the whole *** 377 bp long of *** A+T-rich region is not comprised of large repetitive sequences,but harbors several features characteristic of the lepidopteran insects,including the motif ATAGA followed by an 1. bp poly-T stretch,a microsatellite-like(AT)5 element preceded by the ATTTA motif,an 1. bp polyA-like stretch(AAAAATAAAA)present immediately upstream tRNAMet.

关键词： Lepidoptera Pieridae Delias hyparete Mitochondrial genome

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Applications of molecular fossils in lacustrine stratigraphy

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Chinese Journal Of Geochemistry 2010年第1期29卷 15-20页

作者： WANG Guangli LI Shu WANG Tieguan ZHANG Linye state {1. Laboratories of Petroleum Resources and Prospecting China University of Petroleum Changping Beijing 102249 China Exploration and Production Research Institute S1NOPEC Beijing 100083 China Research Institute ofGeoscience Shengli Oilfield Company SINOPEC Shandong Dongying 257015 China

Biomarkers,or the so-called molecular fossils,are used tentatively in the Eogene lacustrine stratigraphy study in the Jiyang *** the fact that unidentified microfossils or amorphism and acritarchae are widely distributed in lacustrine source rocks,molecular fossils are useful to identify the *** is helpful to reconstruct the palaeo-enviroment,palaeo-ecosystem and compartmentalize the stratigraphic sequence by using molecular fossils with which the existence and types of microbes including bacteria,archaea and certain algae can be identified.

关键词：分子化石湖相地层应用生物标志物湖相烃源岩下第三系生态系统地层划分

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Sequence stratigraphy and Sedimentary Facies of Lower Oligocene Yacheng Formation in Deepwater Area of Qiongdongnan Basin,Northern South China Sea:Implications for Coal-Bearing Source Rocks

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Journal of Earth Science 2014年第5期25卷 871-883页

作者： Jinfeng Ren Hua Wang Ming Sun Huajun Gan Guangzeng Song Zhipeng Sun key {1. of Tectonics and Petroleum Resources Ministry of Education China University of Geosciences Faculty of Earth Resources China University of Geosciences Guangzhou Marine Geological Survey Zhanjiang Branch of CNOOC Limited

For unveiling coal-bearing source rocks in terrestrial-marine transitional sequences, the sequence stratigraphic framework and sedimentary facies of Lower Oligocene Yacheng Formation of Qiongdongnan Basin were investigated using seismic profiles, complemented by well bores and cores. Three third-order sequences are identified on the basis of unconformities on basin margins and correlative conformities in the basin center, namely SQYC3, SQYC2 and SQYC1.from bottom to top. Coal measure in Yacheng Formation of Qiongdongnan Basin were deposited within a range of facies associations from delta plain/tidal zone to neritic sea, and three types of favourable sedimentary facies associations for coal measure were established within the sequence stratigraphic framework, including braided delta plain and alluvial fan, lagoon and tidal flat, and fan delta and coastal plain facies associations. Results shown that, in the third-order sequences, coal accumulation in landward areas（such as delta plain） of the study area predominantly correlates with the early transgressive systems tract（TST） to middle highstand systems tract（HST）, while in seaward areas（such as tidal flat-lagoon） it correlates with the early TST and middle HST. The most potential coal-bearing source rocks formed where the accommodation creation rate（Ra） and the peat-accumulation rate（Rp） could reach a state of balance, which varied among different sedimentary settings. Furthermore, intense tectonic subsidence and frequent alternative marine-continental changes of Yacheng Formation during the middle rift stage were the main reasons why the coal beds shown the characteristics of multi-beds, thin single-bed, and rapidly lateral changes. The proposed sedimentary facies associations may aid in predicting distribution of coal-bearing source rocks. This study also demonstrates that controlling factors analysis using sequence {1. and sedimentology may serve as an effective approach for coal-bearing characteristics

关键词： Qiongdongnan Basin Yacheng Formation sequence stratigraphy sedimentary facies,coal measure.

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