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

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PETROLEUM SCIENCE 2024年第2期21卷 823-835页

作者： Zhang, Yi Kuang, Hong -Wei Liu, Yong-Qing Shi, Qiang Qi, Ke-Ning Wang, Yu-Chong Qiao, Da -Wei Chen, Xiao-Shuai Wu, Li-Zhi Tian, Meng Chen, Long Wei, Yi Song, Liao-Yuan Li, Jian Wu, Zi-Gang Liu, Yun-Qian Liu, Xuan-Chun Chen, An -Qing Liao, Zhi-Wei Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Chongqing Univ Sch Resources & Safety Engn State Key Lab Coal Mine Disaster Dynam & Control Chongqing 400044 Peoples R China Chongqing Bur Geol & Minerals Explorat Geol Team 205 Chongqing 401121 Peoples R China Chongqing Inst Geol Survey Chongqing 401122 Peoples R China Chengdu Univ Technol Key Lab Deep Time Geog & Environm Reconstruct & Ap Minist Nat Resource Chengdu 610059 Sichuan Peoples R China

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 identi fied, which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable fora 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) Member III black 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 E

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating YANGTZE BLOCK DOUSHANTUO FORMATION ZIRCON GLACIATION Area

Ancient water wells reveal a prolonged drought in the lower Yellow River Area about 2800 years ago

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Science Bulletin 2018年第20期63卷 1324-1327页

作者： Shiyong Yu Xuexiang Chen Xiuling Liu Zhen Fang Junfeng Guo Senyang Zhan Hui Fang Fahu Chen School of Geography Geomaticsand PlanningJiangsu Normal UniversityXuzhou 221116China Joint International Research Laboratory for Environmental and Social Archaeology 5handong Universityfinan 250100China Jinan Municipal Institute of Archaeology jinan 250062China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

Proxy records from the North Atlantic realm reveal that large and rapid cooling known as the Bond events continued into the Holocene [1],repeatedly punctuating what is conventionally thought to have been a relatively stable climate.Given that the Holocene is the most recent interglacial period that has spurred the development of modern societies,scrutinizing climate variabil- ity during this period is important not only for predicting the trend of future climate changes,but also for better understanding the driving forces behind the rise and fall of ancient civilizations.

关键词： water wells drought Yellow River Area

Tectonic analysis and petroleum significance of Cenozoic faults in Dongping-Niuzhong Area in Altyn slope

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Petroleum Exploration and Development 2019年第5期46卷 983-990页

作者： DU Wei CHEN Yan WANG Zhendong BIAN Qing GUO Zhaojie Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationBeijing 100871China School of Earth and Space Sciences Peking UniversityBeijing 100871China Qinghai Oilfield Company PetroChinaDunhuang 736202China

The evolution process and petroleum significance of two groups of fault structures,the NW-SE trending and near EW trending ones in the Cenozoic of Dongping-Niuzhong Area of the Altyn slope,Qaidam Basin,were investigated using high precision 3-D seismic data.The NW-SE faults were generated in Oligocene,causing the formation of a series of folds related to transpression faults in the Niuzhong and Dongping Area.After the Miocene,with the continuous extension of the Altyn Tagh strike-slip fault zone,the EW trending faults began to develop massively in Altyn slope.The activity of near EW trending faults and large-scale uplift of the bedrock in the northern Niuzhong Area shared most of the compression torsion in Niuzhong and Dongping Area,consequently,the activity of NW-SE trending faults weakened significantly after the Miocene.Then good hydrocarbon source rocks developed in the inherited Jurassic sags.The faults were effective pathways for oil and gas migration in Dongping and Niuzhong Areas,and the oil and gas charging time matched well with the formation period of the NW-SE trending faults and their related structures,making the fault-related anticlines favorable targets for oil and gas accumulation.The Niuzhong Area has been less affected by the Cenozoic movement after the Miocene,and thus has better conditions for gas reservoir preservation.

关键词： Qaidam Basin Altyn slope Cenozoic tectonic analysis strike-slip fault petroleum significance Dongping-Niuzhong Area

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CFD model simulation of bubble surface Area flux in flotation column reactor in presence of minerals

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International Journal of Mining Science and Technology 2018年第6期28卷 999-1007页

作者： A.R.Sarhan J.Naser G.Brooks Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVictoria 3122Australia Department of Mechanical Engineering University of Anbar RamadiAnbar 31001Iraq

Bubble surface Area flux(S_b) is one of the main design parameter in flotation column that typically employed to describe the gas dispersion properties, and it has a strong correlation with the flotation rate constant. There is a limited information available in the literature regarding the effect of particle type,density, wettability and concentration on Sb. In this paper, computational fluid dynamics(CFD) simulations are performed to study the gas–liquid–solid three-phase flow dynamics in flotation column by employing the Eulerian–Eulerian formulation with k-e turbulence model. The model is developed by writing Fortran subroutine and incorporating then into the commercial CFD code AVL FIRE, v.2014.This paper studies the effects of superficial gas velocities and particle type, density, wettability and concentration on Sband bubble concentration in the flotation column. The model has been validated against published experimental data. It was found that the CFD model was able to predict, where the response variable as indicated by R-Square value of 0.98. These results suggest that the developed CFD model is reasonable to describe the flotation column reactor. From the CFD results, it is also found that Sb decreased with increasing solid concentration and hydrophobicity, but increased with increasing superficial gas velocity. For example, approximately 28% reduction in the surface Area flux is observed when coal concentration is increased from 0 to 10%, by volume. While for the same solid concentration and gas flow rate, the bubble surface Area flux is approximately increased by 7% in the presences of sphalerite.A possible explanation for this might be that increasing solid concentration and hydrophobicity promotes the bubble coalescence rate leading to the increase in bubble size. Also, it was found that the bubble concentration would decrease with addition of hydrophobic particle(i.e., coal). For instance, under the same operating conditions, approximately 23% reduction in the bubble concentration is predicted wh

关键词： CFD Froth flotation Bubble surface Area flux Solid properties Bubble concentration

Effect of reduction in Area per pass on strain distribution and microstructure during caliber rolling in twinning-induced plasticity steel

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Journal of Iron and Steel Research(International) 2020年第1期27卷 62-74页

作者： Joong-ki Hwang Sung Jin Kim School of Mechanical Engineering Tongmyong UniversityBusan 48520Republic of Korea Department of Advanced Materials Engineering Sunchon National UniversitySuncheon 57922Republic of Korea

The effects of reduction in Area(RA)per pass during caliber rolling on microstructure and strain distribution of twinninginduced plasticity steel have been investigated to find solutions to make a more homogeneous material along the radial direction for wire rod applications.The steel wires subjected to an average RA per pass of 2.5%(skin pass caliber rolling)and 10.0%(conventional caliber rolling)were analyzed.The skin pass caliber-rolled wire was characterized as a duplex fiber texture of majorand minor.and the textures were almost same at/between center and surface Area,which is totally different from those of conventional caliber rolling and wire drawing.The skin pass caliber rolling led to more homogeneous microstructure and mechanical properties along the radial direction in comparison with the conventional caliber rolling and wire drawing due to the more homogeneous Hall-Petch hardening,dislocation hardening,and texture behavior with Area,resulting in higher formability.

关键词： Twinning-induced plasticity steel Caliber rolling Deformation twin Reduction in Area Skin pass

Spatial-temporal variations of natural suitability of human settlement environment in the Three Gorges Reservoir Area A case study in Fengjie County,China

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Frontiers of Earth Science 2019年第1期13卷 1-17页

作者： Jieqiong LUO Tinggang ZHOU Peijun DU Zhigang XU Key Laboratory for Satellite Mapping Technology and Applications of State Administration of Surveying Mapping and Geoinformation of China Nanjing UniversityNanjing 210023China Jiangsu Provincial Key Labomtory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China Jiangsu Center for CoUabomtive Innovation in Geographical Information Resource Development and Application Nanjing 210023China School of Geographical Sciences Southwest UniversityChongqing 400715China Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education) Chongqing 400715China

With rapid environmental degeneration and socio-economie development,the human settlement environment (HSE)has experienced dramatic changes and attracted attention from different communities.Consequently,the spatial-temporal evaluation of natural suitability of the human settlement environment (NSHSE)has become essential for understanding the patterns and dynamics of HSE,and for coordinating sustainable development among regional populations,resources,and environments.This study aims to explore the spatialtemporal evolution of NSHSE patterns in 1997,2005,and 2009 in Fengjie County near the Three Gorges Reservoir Area (TGRA).A spatially weighted NSHSE model was established by integrating multi-source data (e.g.,census data,meteorological data,remote sensing images,DEM data,and GIS data)into one framework,where the Ordinary Least Squares (OLS)linear regression model was applied to calculate the weights of indices in the NSHSE model.Results show that the trend of natural suitability has been first downward and then upward, which is evidenced by the disparity of NSHSE existing in the south,north,and central Areas of Fengjie County. Results also reveal clustered NSHSE patterns for all 30 townships.Meanwhile,NSHSE has significant influence on population distribution,and 71.49% of the total population is living in moderate and high suitable districts.

关键词： natural suitability of human settlement environment ordinary least squares model global and local spatial autocorrelation analyses Three Gorges Reservoir Area (TGRA) Fengjie Cotmty

CFD predictions for hazardous Area classification

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Chinese Journal of Chemical Engineering 2019年第1期27卷 21-31页

作者： Andrey Oliveira de Souza Aurélio Moreira Luiz Ant?nio Tavernard Pereira Neto Ant?nio Carlos Brandao de Araujo Heleno Bispo da Silva Sidinei Kebler da Silva Jose Jailson Nicacio Alves Federal Institute of Education Science and Technology of Paraiba Petrobras-Petróleo Brasileiro S.A. Federal University of Campina Grande

This study aimed to describe a Computational Fluid Dynamics(CFD) procedure using the ANSYS CFX software 16.1 and Design of Experiments for the determination of volume and extension of explosive atmospheres due to fugitive emissions of flammable gases.The multidimensional statistical sampling technique Latin Hypercube was used, which defined 100 simulations of random methane gas leak conditions.The CFD model proved to be robust in predicting the extension and volume of the explosive atmosphere for orifice diameters from 0.1 to2.5 mm, pressure from 0.1 MPa to 12 MPa and temperatures from 0 ℃ to 400 ℃.It was found that the calculation domain must be parameterized 8 m in length for each millimeter of the diameter of the source of release to ensure the predictions.In order not to lose precision for very small diameters, the mesh was parameterized with 50 elements along the orifice diameter.It was proved that gravity does not influence the extension and volume of the explosive atmosphere at sonic emissions.The deviation from the ideal gas behavior in the reservoir,achieved by applying the Soave–Redlich–Kwong equation of state, also has not significantly influenced the extension and volume of the explosive atmosphere.The results showed that the size of the explosive atmosphere varies directly with the diameter of the source emission and reservoir pressure, and inversely with the temperature of the reservoir.The diameter of the source is the parameter that has the major effect on the extension of the explosive atmosphere, followed by the pressure and lastly the temperature of the reservoir.

关键词： Computational Fluid Dynamics Computer simulation Safety Fugitive emissions Classified Area Flammable gas cloud

Message delay time distribution analysis for controller Area network under errors

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Frontiers of Information Technology & Electronic Engineering 2019年第6期20卷 760-772页

作者： Lei-ming ZHANG Yi-chao SUN Yong LEI State Key Laboratory of Fluid Power & Mechatronic Systems Zhejiang University Hangzhou 310027 China

Controller Area network(CAN) is a widely used fieldbus protocol in various industrial applications.To understand the network behavior under errors for the optimal design of networked control systems, the message response time of the CAN network needs to be analyzed. In this study, a novel delay time distribution analysis method for the response messages is proposed when considering errors. In this method the complex message queues are decomposed into typical message patterns and cases. First, a stochastic fault model is developed, and the probability factor is defined to calculate the error distribution. Then the message delay time distribution for the single slave node configuration is analyzed based on the error distribution. Next, based on the delay time distribution analysis of typical patterns and cases, an analysis framework of message delay time distribution for the master/slave configuration is developed. The testbed is constructed and case studies are conducted to demonstrate the proposed methodology under different network configurations. Experimental results show that the delay time distributions calculated by the proposed method agree well with the actual observations.

关键词： Cont roller Area network Message delay Probability dist ribution Errors

Mass transfer Area in a multi-stage high-speed disperser with split packing

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Chinese Journal of Chemical Engineering 2019年第4期27卷 772-780页

作者： Tao Ai Aslam M.Mudassar Ziqi Cai Zhengming Gao State Key Laboratory of Chemical Resource Engineering School of Chemical Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

In this study, the mean droplet diameter in the cavity zone and the total mass transfer Area of a multi-stage highspeed disperser(HSD) reactor with different packing combinations were measured and evaluated. The effects of rotational speed and packing radius, as well as the packing ring radius and numbers, on the mean droplet diameter and the total mass transfer Area were evaluated. A model was established to calculate the mass transfer Area in the cavity zone in the HSD reactor, and it was found that the packings contribute 61%–82% of the total mass transfer Area. A correlation for predicting the mass transfer Area in the packing zone was regressed by the dimensionless analysis method. An enhancement factor based on the mass transfer Area in the packing zone was proposed to evaluate the effect of packing combination on mass transfer Area. Two optimum packing combinations were proposed in consideration of the mean droplet diameter and the enhancement factor.

关键词： High-speed disperser Mean droplet diameter Mass transfer Area Split packing