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Gravity-Driven Listric Growth Fault and sedimentation in the Lagoa do Peixe, Rio Grande do Sul Coastal Plain, Brazil

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Open Journal of Geology 2024年第4期14卷 594-616页

作者： Bruno Silva da Fontoura Adelir José Strieder Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes Instituto de Geociê ncias UFRGS Porto Alegre Brazil Engenharia Geoló gica Centro de Engenharias UFPel Pelotas Brasil HIDROSERV— Servi&#231os Geol&#243gicos e Geof&#237sicos Ltda. Porto Alegre Brazil

High frequency, high resolution GPR surveys are successfully applied to investigate near-surface stratification architecture of sedimentary units in coastal plains and to define their depositional conditions. However, low frequency GPR surveys to investigate fault-related depositional systems at greater depths are scarce. This survey was designed investigate a > 100 km long linear escarpment that controls the northwest margin of the Lagoa do Peixe, an important lagoon in Rio Grande do Sul Coastal Plain (RGSCP, Brazil). The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;no deformational structure is admitted to exist before. The low frequency GPR (50 MHz, RTA antenna) and geological surveys carried out in the RGSCP showed the existence of a large, gravity-driven listric growth fault controlling the Lagoa do Peixe escarpment and hangingwall sedimentation. The radargrams in four subareas along the Lagoa do Peixe Growth Fault could be interpreted following the seismic expression of rift-related depositional systems. The radargrams enabled to distinguish three main lagoonal deposition radarfacies. The lower lagoonal radarfacies is a convex upward unit, thicker close to growth fault;the radarfacies geometry indicates that fault displacement rate surpasses the sedimentation rate, and its upper stratum is aged ~3500 l4C years BP. The second lagoonal radarfacies is a triangular wedge restricted to the lagoon depocenter, whose geometry indicates that fault displacement and the sedimentation rates kept pace. The upper lagoonal radarfacies is being deposited since 1060 ± 70 l4C years BP, under sedimentation rate higher than fault displacement rate. The results indicate that low frequency GPR surveys can help in investigating fault-related depositional systems in coastal zones. They also point to a new approach in dealing with RGSCP stratigraphy.

关键词： GPR (Ground-Penetrating Radar) Growth Fault sedimentation Radarfacies Coastal Plain

Pre-Cryogenian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 899-918页

作者： Peiyuan HU Qingguo ZHAI Guochun ZHAO Peter A.CAWOOD Yue TANG Yiming LIU Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Department of Earth Sciences University of Hong KongPokfulam RoadHong Kong 999077China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China School of Earth Atmosphere&EnvironmentMonash UniversityMelbourneVIC 3800Australia

The composition and geological evolution of pre-Cryogenian material in the Tibetan Plateau and its surrounding areas have played an important role in studying the formation and evolution of early supercontinents on Earth.This paper systematically summarizes the characteristics of pre-Cryogenian sedimentation,paleontology,magmatism,and metamorphism in the Tibetan Plateau and its surrounding areas.Based on existing data,the records of pre-Cryogenian sedimentation and paleontology are mainly concentrated in the Meso-Neoproterozoic,with relatively few records from the Paleoproterozoic or earlier.The oldest geological record is the Hadean detrital zircons in the metamorphosed sedimentary rocks of the Himalaya and Qamdo areas(ca.4.0 Ga).The Tibetan Plateau and surrounding areas preserve records related to the formation and evolution of the Kenor supercraton,and the Columbia,Rodinia,and Gondwana supercontinents.Pre-Cryogenian basements can be divided into three types:Tarim-,Yangtze-,and Lhasa-type.The Tarim-type basement has a paleogeographic affinity with the northern margins of the Australian and Indian continents and lacks detrital zircon age peaks and magmatic-metamorphic records related to the Rodinia assembly(ca.1.3-0.9 Ga).The Yangtze-type basement records volcanic activity related to global cooling in the latest pre-Cryogenian period and contains Meso-Neoproterozoic stromatolite and micropaleoflora fossils,as well as magmaticmetamorphic records related to Rodinia assembly(ca.1.1-1.0 Ga).The Lhasa-type basement is characterized by Neoproterozoic rift-related sediment records(ca.900 Ma)and high-pressure metamorphic events(ca.650 Ma),with a prominent peak of detrital zircon ages of ca.1.2-1.1 Ga.It is likely to have a paleogeographic affinity with the African continent.

关键词： Tibetan Plateau Pre-Cryogenian sedimentation Fossils Paleogeographic evolution

Prospects of sediment deposition at small watershed scale in the black soil region of Northeast China: A mini review

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Pedosphere 2024年第1期34卷 30-35页

作者： Guanghui ZHANG Yang YANG Yingna LIU Zhiqiang WANG State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Sediment deposition is one of the most significant processes in small watersheds characterized by gentle long hillslopes in the black soil(Mollisol)region of Northeast China, as indicated by severe ephemeral gully and gully erosion on hillslopes and very low sediment concentrations in river systems.Few reviews have been conducted to summarize the related research in this region. The objectives of this review were to identify the potential factors influencing sediment deposition, review related studies, and propose future research needs in the black soil region of Northeast China. Sediment deposition is controlled by the deficit between sediment transport capacity of flow and sediment load. Hence, all factors affecting flow transport capacity and sediment load directly affect sediment deposition. For a specific small watershed, the change in slope gradient along the flow path is the key factor affecting sediment deposition. Shelterbelts, ridge tillage systems, terraces, grass strips, road distribution, ponds and reservoirs, and land-use patterns also influence the spatial distribution and rate of deposition. The trace method has been widely used to quantify sediment deposition in this region. The results of cesium-137(^(137)Cs),lead-210(^(210)Pb), and magnetic susceptibility reveal that serious deposition occurs on the back and foot slopes. Distinct deposition occurs in front of contour shelterbelts. Future studies should focus on the methodology, spatial and temporal variations, dominant influencing factors and their mechanisms, and the potential effects on land productivity within specific small watersheds and across the black soil region. This review provides insights into the sediment deposition process in small watersheds characterized by gentle, long hillslopes.

关键词： Mollisol sedimentation soil and water conservation soil erosion soil redistribution

Cell sedimentation during 3D bioprinting:amini review

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Bio-Design and Manufacturing 2022年第3期5卷 617-626页

作者： Heqi Xu Jiachen Liu Zhengyi Zhang Changxue Xu Department of Industrial Manufacturingand Systems EngineeringTexas Tech UniversityLubbockTX 79409USA School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China

Introduction In the past decade,three-dimensional(3D)bioprinting,which precisely deposits bioink composed of the biological materials and the living cells into delicate structures with the living cells encapsulated,has made numerous important advances in tissue engineering and regenerative medicine[1,2].Depending on the printing mechanism,3D bioprinting technologies are generally categorized into four types:inkjet-based bioprinting,microextrusion-based bioprinting,laser-assisted bioprinting,and stereolithography-based bioprinting[3].

关键词： printing sedimentation precisely

LAZing around: The intricate dance of amyloplast sedimentation and gravity sensing in plants

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Molecular Plant 2023年第12期16卷 1887-1889页

作者： Ning Zhang Songtao Gui Yonghong Wang National Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai'an 271018China institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing100101China institute of Biology Il Faculty of BiologyUniversity of Freiburg79104 FreiburgGermany Signaling Research Centres BIOSS and CIBSS University of Freiburg79104 FreiburgGermany

Gravitropism,the remarkable ability of plants to adjust their growth in response to gravity,is fundamental to their existence on Earth.Pioneering research on gravitropism can date back to the work in the 1880s,notably... 详细信息

关键词： adjust sedimentation Pioneer

Study of gravitational sedimentation of flexible, permeable circular and planktonic particle applying the immersed boundary method

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International Journal of Sediment Research 2023年第5期38卷 643-652页

作者： Rekha Panghal Sudeshna Ghosh Department of Mathematics Amity School of Applied Sciences Amity University Haryana

The gravitational settling of a flexible, permeable circular and planktonic particle drenched in a fluid which is assumed to be Newtonian and incompressible along with being viscous was studied. A mathematical formulation and numerical simulations of the studied problem were done by applying the Immersed Boundary Method(IBM) in a two-dimensional fluid domain. Parametric studies were done for analyzing the impact of varying flexibilities and permeabilities with reference to settling velocity(terminal velocity) and shape deformation of the particle. The terminal velocity and permeability of the particle are directly proportional. It was observed that for fixed permeability, the terminal velocity increases when increasing the flexibility of the particle.

关键词： Immersed Boundary Method (IBM) sedimentation Incompressible fluid Flexible particle Permeable particle Settling velocity

Dynamical Demixing of a Binary Mixture Under sedimentation

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Communications in Computational Physics 2023年第1期33卷 1-21页

作者： Andre S.Nunes Rodrigo C.V.Coelho Vasco C.Braz Margarida M.Telo da Gama Nuno A.M.Araujo Centro de F´ısica Te´orica e Computacional Faculdade de CiˆenciasUniversidade de LisboaP-1749-016 LisboaPortugal Departamento de F´ısica Faculdade de CienciasUniversidade de LisboaP-1749-016 LisboaPortugal Electric Ant Lab Science Park 1061098 XGAmsterdamThe Netherlands

We investigate the sedimentation dynamics of a binary mixture,the species of which differ by their Stokes coefficients but are identical otherwise.We analyze the sedimentation dynamics and the morphology of the final deposits using Brownian dynamics simulations for mixtures with a range of sedimentation velocities of both species.In addition,we use the lattice Boltzmann method to study hydrodynamic effects.We found a threshold in the difference of the sedimentation velocities above which the species in the final deposit are segregated.The degree of segregation increases with the difference in the Stokes coefficients or the sedimentation velocities above the threshold.We propose a simple analytical model that captures the main features of the simulated deposits.

关键词： sedimentation Brownian dynamics lattice Boltzmann method

sedimentation of short cylindrical pollutants with mechanical contacts

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Journal of Environmental Sciences 2005年第6期17卷 906-911页

作者： LIN Jian-zhong WANG Ye-long ZHANG Wei-feng Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Institute of Marine and Coastal Sciences Rutgers University New Brunswick New Jersey USA

Lattice Boltzmann method and elastic particle collision model were used to investigate the sedimentation of short cylindrical pollutant particles with mechanical contacts for varying bulk number density ε and terminal Reynolds number ReT. The corresponding experiments were performed as a comparison. The clusters of pollutant particles with an inverted “T” structure were observed, the pollutant particles for high ε and large ReT scattered wider than that for low ε and small ReT. The sedimentation velocities increased suddenly at the initial stage, then decreased drastically, after that swayed around and approached to a steady value. The time to steady state did not depend on ε and ReT. The effect of particle interactions was to hinder the average sedimentation velocity, and hindrance was directly proportional to ε. The orientation distributions of pollutant particles depended on ReT and ε, especially on the former. Both the standard deviations of vertical and horizontal velocity, the former was larger than the latter, were nearly independent on ε and ReT.

关键词： cylindrical pollutant particles sedimentation lattice-Boltzmann simulation experiment mechanical contact

sedimentation OF CIRCULAR PARTICLES IN OLDROYDB FLUID

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Journal of Hydrodynamics 2004年第3期16卷 254-259页

作者： SHAOXue-ming YUZhao-sheng DepartmentofMechanics ZhejiangUniversityHangzhou310027China DepartmentofMechanicalandMechatronicEngineering TheUniversityofSydneyNSW2006Australia

The sedimentation of circular particles in a vertical channel filled withOldroyd ― B fluid was studied by an improved Distributed Lagrange Multiplier/fictitious domain(DLM) method. The sedimenting behaviors of two particles are presented firstly, which shows that,when the particles are dropped in a viscoealstic fluid, the stable configuration is the one wherethe particles are aligned parallel to the flow direction when the Mach number Mis less than 1 andthe elasticity number E is greater than 1. This agrees well with the known experimental in Ref. [1]and simulation results in Ref. [2]. Our simulations also show that, as in Newtonian fluid, thesedimentation of the particles will be accelerated due to the .interaction between particles in aviscoealstic fluid.

关键词： sedimentation circular particle distributed lagrange multiplier/fictitiousdomain (DLM) method visco-elastic fluid