检索结果-南通市图书馆

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

引用

Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang hong-wei kuang Yong-Qing Liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-wei Qiao Xiao-Shuai Chen Li-Zhi Wu Meng Tian Long Chen Yi wei Liao-Yuan Song Jian Li Zi-Gang Wu Yun-Qian Liu Xuan-Chun Liu An-Qing Chen Zhi-wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent years.However,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic pattern.This study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern Sichuan.The results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied area.The Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb dating.Regional stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three Gorges.Typically,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast sandstones.The proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing strata.During the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early Ediacaran.Overall,the early Ediacaran of northeastern Sichuan succeeded the paleogeogr

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Review of molar tooth structure research

引用

Journal of Palaeogeography 2014年第4期3卷 359-383页

作者： hong-wei kuang Institute of Geology Chinese Academy of Geological Sciences

For more than a century, molar tooth structure （MTS） has been studied. The study developed in three stages. During the first stage （before 1980）, researchers described three basic morphologies of MTS, mainly from the Belt Supergroup in North America, and they provided several hypotheses for the origin of MTS. During the second stage （1980-1999）, the frequent discoveries of MTS on all continents resulted in many detailed descriptions of their shape and in several hypotheses concerning the origin of MTS. Notably, hypotheses of MTS＇s origin such as seismic activity and biological activity were developed. Since 2000, research has progressed into a new stage （the third stage）. This is due to discoveries of MTS in the Me- so-Neoproterozoic of China and elsewhere, and the ongoing debate on the seismic or biologi- cal origin is replaced by a hypothesis that involves gas expansion and chemically-controlled carbonate precipitation （both of them possibly affected by biological activities）. This latter idea has gradually been commonly recognized as the mainstream theory. Despite continued disa- greements, researchers now agree that microsparry calcite played a controlling role regarding the development and the global distribution of MTS in time and space during the Proterozoic, the morphological diversity, and the impact on the sedimentary environment. The present con- tribution analyses the three major hypotheses regarding the origin of MTS; it also discusses the shortcomings of the hypotheses regarding a seismic or biologic origin, and it details the modern hypothesis that links formation of cracks to the precipitation of sparry calcite. It is de- duced that important questions dealing with the Precambrian can be answered, among other aspects regarding the depositional palaeogeography and stratigraphic correlations.

关键词： molar tooth structure sparry calcite Precambrian

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical modelling of channel migration with application to laboratory rivers

引用

International Journal of Sediment Research 2015年第1期30卷 13-27页

作者： Jian SUN Bin-liang LIN hong-wei kuang State key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua University State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua University Cardiff School of Engineering CardiffWales CF243AAUK Changjiang Waterway Planning Design and Research Institute

The paper presents the development of a morphological model and its application to experimental model rivers.The model takes into account the key processes of channel migration,including bed deformation,bank failure and wetting and drying.Secondary flows in bends play an important role in lateral sediment transport,which further affects channel migration.A new formula has been derived to predict the near-bed secondary flow speed,in which the magnitude of the speed is linked to the lateral water level gradient.Since only non-cohesive sediment is considered in the current study,the bank failure is modelled based on the concept of submerged angle of repose.The wetting and drying process is modelled using an existing method.Comparisons between the numerical model predictions and experimental observations for various discharges have been made.It is found that the model predicted channel planform and cross-sectional shapes agree generally well with the laboratory observations.A scenario analysis is also carried out to investigate the impact of secondary flow on the channel migration process.It shows that if the effect of secondary flow is ignored,the channel size in the lateral direction will be seriously underestimated.

关键词： Channel migration Numerical modelling Sediment transport Secondary flow

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Mesozoic basins and associated palaeogeographic evolution in North China

引用

Journal of Palaeogeography 2015年第2期4卷 189-202页

作者： Yong-Qing Liu hong-wei kuang Nan Peng Huan Xu Peng Zhang Neng-Sheng Wang wei An Institute of Geology Chinese Academy of Geological Sciences

In North China, the Mesozoic terrestrial basins, sedimentary palaeogeography and tectonic settings involved five evolutionary stages：（1） the Early-Middle Triassic, （2） the Late Triassic to Early-Middle Jurassic, （3） the Late Jurassic to early Early Cretaceous, （4） the middle-late Early Cretaceous and （5） the Late Cretaceous. The regional punctuated tectonic events occurred during these evolutionary stages. During the Early-Middle Triassic （stage 1）, the Xingmeng Orogenic Belt （XMOB, i.e., east- ern part of Central Asia Orogenic Belt, CAOB） of the northern North China was settled in the transition of tectonic environment from syn-orogenic compression to post-orogenic extension with intensive uplifting. It is a main provenance in the unified Ordos-North China Basin.The united continental plate of China and the Qinling-Dabie-Sulu Orogenic Belt formed due to convergence and collision between the North China Plate and the Yangtze Plate along two suture zones of the Mianlue and the Shangdan in the terminal Middle Triassic. During the Late Triassic to the Early-Middle Jurassic （stage 2）, the Late Triassic mafic or alkaline rocks and intrusions occurred on the northern and southern margins of North China Craton （NCC） and XMOB, implying that intensified extension happened all over the North China （early phase of stage 2）. Additionally, in the late phase of stage 2, the basic volcanic- filing faulted basins were widely distributed in the northeastern North China during the Early- Middle Jurassic, including a series of smalt- to medium-sized basins with coal-bearing strata and some volcanic rocks in other areas of North China, which was the result of subduction of the Palaeo-Pacific Plate during the Early-Middle Jurassic. An active continental margin with accretionary complex developed in the eastern Heilongjiang of China, Japan and the Far East of Russia at that time. However, in the end of the Early-Middle Jurassic, because of the Yan- shanian orogeny characterized by complicated thrust and fold, the previous unified O

关键词： Mesozoic basin orogenic belt tectonic zone palaeogeography North China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Detrital zircon dating and tracing the provenance of dinosaur bone beds from the Late Cretaceous Wangshi Group in Zhucheng, Shandong, East China

引用

Journal of Palaeogeography 2016年第1期5卷 72-99页

作者： wei An hong-wei kuang Yong-Qing Liu Nan Peng Ke-Min Xu Huan Xu Peng Zhang Ke-Bai Wang Shu-Qing Chen Yan-Xia Zhang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Shandong Institute of Geology Survey Jinan 250000 Shandong China School of Earth Sciences and Resources China University of Geosciences (Beijing) Beijing 100083 China Dinosaur Research Center of Zhucheng Zhucheng 262200 Shandong China

The mass burial of dinosaur bone fossils in the Late Cretaceous Wangshi Group in Zhu- cheng, Shandong Province has been a research focus in recent years. However, the prov- enance of the dinosaur bone fossils and the accurate depositional age of the bone beds remain ambiguous. Through U-Pb dating of detrital zircons collected from six conglom- erate samples from the dinosaur bone beds, we found that the youngest single grain age （YSG） of sample 090414-24-D was 77.3 Ma, representing the maximum depositional age of the dinosaur fossil beds and sediments. This also indicates that the hongtuya Formation was deposited during the Campanian. Dating results revealed an age peak of 120 110 Ma, which corresponds with the peak age of volcanic rocks of the Lower Cretaceous Qingshan Group. The volcanic rocks of the Qingshan Group are mainly exposed in Laiyang, to the north of Zhucheng, although a few also appear to the south and northwest. Through analysis of conglomerate composition and palaeocurrents in the sediments containing the bone beds, we found that the three different data sets of gravel compositions of the con- glomerates were mainly composed of volcanic or pyroclastic rocks. Three different data sets of palaeocurrents suggested that the main sediment source of the Wangshi Group dinosaur bone beds was from the north-northwest of the Basin. Only one data set had a provenance south of the basin. This study revealed that the areas of Laiyang and the Yishu Fault Zone were the main provenance areas of both the dinosaur bone fossils and the sediments of the Wangshi Group in Zhucheng. The southern margin of the Zhucheng Basin may be a secondary source area. This research provides an important basis for judging the deposition time and the sediment source of fossil layers in the Wangshi Group, as well as reconstructing the palaeogeography of the Wangshi Group in the liaolai Basin.

关键词： Dinosaur bone beds Provenance Detrital zircon Geochronology Wangshi GroupShandong Zhucheng

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Manganese carbonate stromatolites of the Ediacaran Doushantuo Formation in Chengkou,northern Yangtze Craton,China

引用

Journal of Palaeogeography 2021年第3期10卷 356-381页

作者： Yi Zhang Jian Li Long Chen Yi wei Qiang Shi Dong-Ge Wang Qing-Ming Wu Liao-Yuan Song Meng Tian hong-wei kuang Yong-Qing Liu Kaarel Mänd Hua-Qing Bai Zi-Liang Liu Yu-Chong Wang Da-wei Qiao Wen-Jun Zhu No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing 402160China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Department of Earth and Atmospheric Sciences University of AlbertaEdmontonAlberta T6G 2E8Canada Department of Geology University of TartuTartu 50411Estonia State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059Sichuan ProvinceChina PetroChina Xinjiang Oilfield Company Karamay 834099Xinjiang Uygur Autonomous RegionChina

The origin process of manganese ores remains unsolved worldwide.Exploring the origins of stromatolites that contain manganese may be a key to deciphering the sedimentary environments and metallogenic processes of these deposits.However,only a few manganese stromatolites have been discovered and described until now.Microbialites are well developed in the manganese deposits,located near the top of the Ediacaran Doushantuo Formation in Chengkou area of Chongqing,northern Yangtze Craton,but has not been explicitly studied;and whether they are true stromatolites or Epiphyton microbialites remains controversial.Based on field and core observations and thin section microscopy,the characteristics of five types of manganese stromatolites and their growth modes are described in detail in this study.The results show that these stromatolites grew in a biostrome in shoal and lagoon environments and were syngenetic with oncolites and oolites on a carbonate ramp behind the shoal.Manganese stromatolites can be categorized into three forms:(1)stratiform;(2)columnar,which includes branched and columnar types;and(3)stratiform-columnar,which is a transitional type.Based on a criterion that the diameter is less than or greater than 1 mm,columnar stromatolites are further divided into micro-columnar(1 mm)columns,which display synchronous growth and are similar to Pseudogymnosolenaceae.Their shapes are mainly controlled by water depths and hydrodynamic strengths.The greater the water depth,the more columnar the columns tend to be.Excessively strong hydrodynamic conditions decrease the growth rate of stromatolites,and they even stopped growth due to wave damage.Furthermore,pillared laminar textures(not Epiphyton),which consist of dendritic,micro-branched and microcolumnar stromatolites,are a common feature of the larger stratiform,stratiform-columnar and columnar stromatolites.The alternations of laminae with different internal textures record subtle fluctuations in water depths and hydrodynamic strengths,which indic

关键词： Microbialites Manganese stromatolites Ediacaran Doushantuo Formation Yangtze Craton Growth mode

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stromatolite characteristics of Mesoproterozoic Shennongjia Group in the northern margin of Yangtze Block, China

引用

China Geology 2019年第3期2卷 364-381页

作者： hong-wei kuang Zheng-xiu Fan Yong-qing Liu Nan Peng Zhi-cai Zhu Zhen-rui Yang Zhi-xian Wang Hui-liang Yu Quan Zhong Institute of Geology Chinese Academy of Geological SciencesBeijing100037China College of Resources and Environment Yangtze UniversityWuhan430100China Administration of Shennongjia National Park ShengnongjiaHubei442421China

Mesoproterozoic Shennongjia Group in Shennongjia Area can be divided into three subgroups in ascender order. Of which the lower subgroup includes Yingwodong, Dayanping, Macaoyuan, Luanshigou, Dawokeng and kuangshishan formations;the middle subgroup is formed by Yemahe, Wenshuihe and Shicaohe formations;the upper subgroup consists of Songziyuan and Wagangxi formations. Stromatolites developed very well in the carbonate rocks of each subgroup in Shennongjia Group. Based on descriptions of stromatolites macrotypes and their characteristics, this paper studied the formation environments, discussed the relationship among types, sizes, abundance of stromatolites and sedimentary environment, and established the formation and development pattern of stromatolites. As a result, this research also reveals the paleoenvironment and paleoclimate during the period of the Shennongjia Group deposited, which is beneficial to the study of paleoenvironment, paleogeography and paleoclimate, stratigraphic succession and regional correlation of the northern edge of Yangtze block. Stromatolites of Shennongjia Group are mainly conical, columnar, domal, wavy, stratiform and stromatolite reefs. The columnar and conical stromatolites are well developed. Conical stromatolites are mainly monomers, with a variety of pyramidal types, ranging in diameter from a few millimeters to several meters and formed in the high energy subtidal zone and tidal lagoon environment. Most of the columnar stromatolites are medium to small sizes implied a wide and gentle slope environment at that time. Stratiform (including wavy) stromatolites are larger scales and extends far away and distributed most widely in almost every horizon in the carbonate rocks. Stratiform stromatolites can be formed in low energy environments such as subtidal and intertidal zones and supratidal belts. Wavy stromatolites often developed in the hydrodynamic energy condition from weak energy intertidal zone gradually strengthened to the below of the high energy supratidal. Although stroma

关键词： Stromatolite Mesoproterozoic Shennongjia Group Shennongjia Area Northern Margin of Yangtze Craton Geological survey engineering China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Time evolutions of scalar field perturbation in Schwarzschild de-Sitter black hole from Einstein-scalar–Gauss–Bonnet theory

引用

Communications in Theoretical Physics 2024年第1期76卷 76-81页

作者： Cheng Xu Zhen-Hao Yang Xiao-Mei kuang Rui-hong Yue Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou225009China

The scalar-free black hole could be unstable against the scalar field perturbation when it is coupled to a Gauss–Bonnet(GB)invariant in a special form.It is known that the tachyonic instability in this scenario is triggered by the sufficiently strong GB coupling.In this paper,we focus on the time domain analysis of massive scalar field perturbation around the Schwarzschild de-Sitter black hole in Einstein-scalar–Gauss–Bonnet gravity.By analyzing the scalar field propagation,we find that the scalar field will finally grow when the GB coupling is large enough.This could lead to the instability of the background black hole.Furthermore,we demonstrate how the mass of the scalar field and the GB coupling strength affect the onset of tachyonic instability.

关键词： black hole perturbation scalar-Einstein-Gauss-Bonnet gravity time domain evolution me

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Design and construction of size-controlled CoO/CS catalysts for Fischer–Tropsch synthesis

引用

Nano Research 2024年第4期17卷 2520-2527页

作者： wei Sun Ting kuang Guiyou wei Yue Li Yaqin Liu Shuai Lyu Yuhua Zhang Jinlin Li Li Wang Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science South-Central Minzu UniversityWuhan 430074China Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China

The use of supported Co-based catalysts is widespread in various catalytic reactions due to their unique structures.The structural sensitivity of these catalysts is closely linked to their particle size and crystal form.Consequently,comprehending the structure–activity relationship requires the development of well-defined Co-based catalysts.Herein,we employed a colloidal wet chemical process and a heterogeneous nucleation method to prepare well-defined Co-based catalysts supported by inert carbon nanospheres.The nanospheres’surface possesses abundant functional groups that efficiently capture metal complexes and facilitate the nucleation and growth of CoO nanoparticles.By adjusting the Co source concentration,solvent molar ratio,and nucleation growth kinetics,we successfully prepared CoO/carbon sphere(CS)catalysts with different particle sizes and crystal forms.The influence of metallic face-centered cubic(fcc)-Co^(0) particle size in the range of 6.6–17.6 nm on the performance of Fischer–Tropsch synthesis(FTS)using well-defined CoO/CS catalysts has been investigated.The result demonstrated that the turnover frequency(TOF)remained constant for CoO/CS catalysts with metallic fcc-Co^(0) particle size larger than 7.7 nm.However,both the selectivity and the activity changed for CoO/CS catalysts with smaller particles(<7.7 nm).Significantly,when metallic fcc-Co^(0) particle size was reduced from 17.6 to 7.7 nm,the cobalt time yield increased to 6.7μmolCO·gCo^(-1)·s^(-1),indicating improved catalytic activity.At the same time,the CH_(4) selectivity decreased to 4.9%,suggesting a higher preference for hydrocarbon production.These findings demonstrate the importance of particle size in Co catalyzed Fischer–Tropsch synthesis.The use of well-defined CoO/CS catalysts offers valuable insights into the structure–activity relationship,leading to a better understanding of Co catalyzed Fischer–Tropsch synthesis.

关键词： Fischer–Tropsch synthesis(FTS) cobalt size effects phase effects carbon nanospheres

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Distributed Matching Theory-Based Task Re-Allocating for Heterogeneous Multi-UAV Edge Computing

引用

China Communications 2024年第1期21卷 260-278页

作者： Yangang Wang Xianglin wei Hai Wang Yongyang Hu kuang Zhao Jianhua Fan College of Communications Engineering Army Engineering University of PLANanjing 210007China The Sixty-Third Research Institute National University of Defense TechnologyNanjing 210007China

Many efforts have been devoted to efficient task scheduling in Multi-Unmanned Aerial Vehicle(UAV)edge computing.However,the heterogeneity of UAV computation resource,and the task re-allocating between UAVs have not been fully considered yet.Moreover,most existing works neglect the fact that a task can only be executed on the UAV equipped with its desired service function(SF).In this backdrop,this paper formulates the task scheduling problem as a multi-objective task scheduling problem,which aims at maximizing the task execution success ratio while minimizing the average weighted sum of all tasks’completion time and energy consumption.Optimizing three coupled goals in a realtime manner with the dynamic arrival of tasks hinders us from adopting existing methods,like machine learning-based solutions that require a long training time and tremendous pre-knowledge about the task arrival process,or heuristic-based ones that usually incur a long decision-making time.To tackle this problem in a distributed manner,we establish a matching theory framework,in which three conflicting goals are treated as the preferences of tasks,SFs and UAVs.Then,a Distributed Matching Theory-based Re-allocating(DiMaToRe)algorithm is put forward.We formally proved that a stable matching can be achieved by our proposal.Extensive simulation results show that Di Ma To Re algorithm outperforms benchmark algorithms under diverse parameter settings and has good robustness.

关键词： edge computing heterogeneity matching theory service function unmanned aerial vehicle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：