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Provenance and drainage system of the Early Cretaceous volcanic detritus in the Himalaya as constrained by detrital zircon geochronology

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Journal of Palaeogeography 2015年第1期4卷 85-98页

作者： Xiu-Mian Hu Eduardo Garzanti Wei An State Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Department of Earth and Environmental Sciences Università di Milano?BicoccaMilano 20126 Italy

The age range of the major intra-plate volcanic event that affected the northern Indian margin in the Early Cretaceous is here defined precisely by detrital zircon geochronology. U-Pb ages of Early Cretaceous detrital zircons found in the Cretaceous to the Paleocene sandstones cluster mainly between 142 Ma and 123 Ma in the northern Tethys Himalayan unit, and between 140 Ma and 116 Ma in the southern Tethys Himalayan unit. The youngest and oldest detrital zircons within this group indicate that volcanism in the source areas started in the latest Jurassic and ended by the early Albian. Stratigraphic data indicate that volcaniclastic sedimentation began significantly earlier in southern Tibet （Tithonian） than in Nepal （Valangin- ian）, and considerably later in Spiti and Zanskar （Aptian/AIbian） to the west. This apparent westward migration of magmatism was explained with progressive westward propagation of extensional/transtensional tectonic activity and development of fractures cutting deeply across the Indian continental margin crust. However, detrital zircon geochronology provides no indication of heterochroneity in magmatic activity in the source areas from east to west, and thus lends little support to such a scenario. Westward migration of volcaniclastic sedimentation may thus reflect instead the westward progradation of major drainage systems supplying volcanic detritus sourced from the same volcanic centers in the east. Development of multiple radial drainage away from the domal surface uplift associated with magmatic upwelling, as observed for most large igneous provinces around the world, may also explain why U-Pb ages of detrital zircons tend to cluster around 133-132 Ma （the age of the Cornel igneous province） in Tethys Himalayan units, but around 118-117 Ma （the age of the Rajmahal igneous province） in Lesser Himalayan units.

关键词： northern Indian margin Cretaceous Himalayan Orogen volcaniclastic detri-tus drainage system zircon geochronology palaeogeography

Occurrence and Decay of SARS-CoV-2 in Community Sewage drainage systems

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Engineering 2023年第7期26卷 214-219,I0008,I0009页

作者： Qian Dong 蔡俊雄刘艳臣凌海波 Qi Wang Luo-Jing Xiang Shao-Lin Yang Zheng-Sheng Lu Yi Liu Xia Huang 曲久辉 State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Hubei Provincial Academy of Eco-Environmental Sciences Wuhan 430072China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The rapid spread of the coronavirus disease(COVID-19)pandemic in over 200 countries poses a substantial threat to human health.Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which causes COVID-19,can be discharged with feces into the drainage system.However,a comprehensive understanding of the occurrence,presence,and potential transmission of SARS-CoV-2 in sewers,especially in community sewers,is still lacking.This study investigated the virus occurrence by viral nucleic acid testing in vent stacks,septic tanks,and the main sewer outlets of community where confirmed patients had lived during the early days of the epidemic in Wuhan,China.The results indicated that the risk of long-term emission of SARS-CoV-2 to the environment via vent stacks of buildings was low after confirmed patients were hospitalized.SARS-CoV-2 were mainly detected in the liquid phase,as opposed to being detected in aerosols,and its RNA in the sewage of septic tanks could be detected for only four days after confirmed patients were hospitalized.The surveillance of SARS-CoV-2 in sewage could be a sensitive indicator for the possible presence of asymptomatic patients in the community,though the viral concentration could be diluted more than ten times,depending on the sampling site,as indicated by the Escherichia coli test.The comprehensive investigation of the community sewage drainage system is helpful to understand the occurrence characteristics of SARS-CoV-2 in sewage after excretion with feces and the feasibility of sewage surveillance for COVID-19 pandemic monitoring.

关键词： SARS-CoV-2 Transmission risk drainage system Sewage Community

Analysis of COVID-19 clusters involving vertical transmission in residential buildings in Hong Kong region

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Building Simulation 2023年第5期16卷 701-711页

作者： Pengcheng Zhao Department of Mechanical Engineering The University of Hong KongPokfulamHong KongChina

Multiple clusters of coronavirus disease 2019(COVID-19)in Hong Kong have involved vertical transmissions in residential buildings,wherein the flats of confirmed cases were often vertically aligned.Data on the buildings and cases associated with 19 such clusters were retrieved and compared with the corresponding data on the entirety of Hong Kong region.Vertical transmissions usually occurred in old high-rise buildings with small flat areas and low estate prices during winter.In addition,infection occurred frequently among the elderly and among upstairs neighbours of index cases.Virus-laden aerosols may have been transmitted between flats mostly via shared drainpipes,and the vertical distribution of the confirmed cases in a building varied by its drainage system design.For buildings with their entire drainpipes installed indoors,both the upstairs and downstairs neighbours of the index case flats could be infected.By comparison,buildings with their drainage stacks installed outdoors had lower infection risks and demonstrated a clearer pattern of vertical transmission:most infected cases resided upstairs from the index case flats,indicating that the virus spread could be dominated by the stack effect.This study provides valuable data and analysis for developing epidemic control strategies for residential buildings.

关键词： drainage system high-rise building infection SARS-CoV-2 stack effect ventilation

Urban drainage Network Scheduling Strategy Based on Dynamic Regulation: Optimization Model and Theoretical Research

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Intelligent Automation & Soft Computing 2023年第8期37卷 1293-1309页

作者： Xiaoming Fei College of Environmental Science and Engineering Tongji UniversityShanghai200092China

With the acceleration of urbanization in China,the discharge of domestic sewage and industrial wastewater is increasing,and accidents of sewage spilling out and polluting the environment occur from time to time.Problems such as imperfect facilities and backward control methods are com-mon in the urban drainage network systems in China.Efficient drainage not only strengthens infrastructure such as rain and sewage diversion,pollution source monitoring,transportation,drainage and storage but also urgently needs technical means to monitor and optimize production and operation.Aiming at the optimal control of single-stage pumping stations and the coordinated control between two-stage pumping stations,this paper studies the modelling and optimal control of drainage network systems.Based on the Long Short Term Memory(LSTM)water level prediction model of the sewage pumping stations,and then based on the mechanism analysis of drainage pipe network,the factors that may cause the water level change of pumping station are obtained.Grey correlation analysis is carried out on these influencing factors,and the prediction model is established by taking the factors with a high correlation degree as input.The research results show that compared with the traditional prediction model,the LSTM model not only has higher prediction accuracy but also has better inflection point tracking ability.

关键词： LSTM neural network urban drainage network drainage system scheduling strategy optimization

Variation of hydro-environment during past four decades with underground sponge city planning to control flash floods in Wuhan,China:An overview

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Underground Space 2020年第2期5卷 184-198页

作者： Hui-Long Wu Wen-Chieh Cheng Shui-Long Shen Meng-Ying Lin Arul Arulrajah Department of Civil Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering School of Civil EngineeringXi’an University of Architecture and TechnologyXi’an 710055China Department of Civil and Environmental Engineering College of EngineeringShantou UniversityShantouGuangdong 515063China Department of Civil Engineering School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Civil and Construction Engineering Swinburne University of TechnologyVictoria 3122Australia

This paper presents a review of the variation in the hydro-environment over the past four decades in Wuhan,China,and discusses its close relationship with flash flood events.These flash flood events have inundated underground infrastructures and resulted in significant economic losses and casualties,which are also discussed in relation to various external and internal factors.The external factors are predominantly owing to heavy rainstorms resulting from extreme climate change.The internal factors predominantly include a decrease in wetland areas,changes in topography,and disrepair of drainage systems in urban areas.Since the 1970s,lakes in Wuhan have been significantly reduced in size(by approximately 40%).This reduction in wetland area decreases the water storage capacity in urban areas,and the frequency of large flooding events thus increased from 0.1 event/year to approximately 0.2 event/year.Additionally,the disrepair of drainage systems in urban areas has reduced their ability to resist flood hazards.Changes in topography have also intensified the flood volume per unit time,further burdening the drainage systems.In 2016,Wuhan suffered from several large flooding events that led to some of the most severe economic losses in recorded history.The drainage system at the urban center of Wuhan and proposed flood prevention methods are discussed in detail in this paper.The sponge city(SPC)concept has been attempted in Qingshan District,Wuhan,and its success proved the reliability of the theory.A SPC is believed to reduce the impacts of future flash floods in China and other developed and developing countries.

关键词： Flash flooding Wetland area drainage system Wuhan Sponge city

Towards an optimization design of seepage control：A case study in dam engineering

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Science China(Technological Sciences) 2017年第12期60卷 1903-1916页

作者： LI Xing CHEN YiFeng HU Ran YANG ZhiBing State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

High dams generally suffer from higher seepage risks in their foundations, and seepage control is an important technology for limiting the amount of leakage and improving the stability of the foundations. In this study, a procedure was proposed for optimization design of seepage control system in large-scale hydropower projects, which relies on sufficient characterization of site conditions and proper quantification of the performance of the seepage control system. The proposed procedure was applied to the design of seepage control system in the Mengdigou Hydropower Station consisting of a double-curvature arch dam201 m in height. An optimized layout of the seepage control system, including the extended length of grout curtain, the rows of grouting holes and the spacing of drainage holes, was suggested. The proposed procedure provides a guide with lower risk and higher confidence for performance assessment and optimization design of seepage control systems in high dam engineering.

关键词： rock foundation seepage control grout curtain drainage system optimization design

drainage and Preliminary Risk of Flooding in an Urban Zone of Eastern Amazon

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Journal of Geoscience and Environment Protection 2023年第5期11卷 1-16页

作者： Taís Silva Sousa Clezio Júnior Teixeira Viegas Helenilza Ferreira Albuquerque Cunha Alan Cavalcanti da Cunha Graduate Program in Environmental Sciences Federal University of Amapá Macapá Brazil Graduate Program in Tropical Biodiversity Federal University of Amapá Macapá Brazil Graduate Program in Biotechnology Federal University of Amapá Macapá Brazil

drainage system is a poorly investigated basic sanitation and urban planning issue in the Amazon, which is often related to flooding processes and public health. The aim of the present research is to correlate Preliminary Risk of Flooding (PRF) to independent variables, based on the following methodology: 1) identifying and classifying risk areas by using the Geographic Information system (GIS) and 2) statistically correlating risk to sanitary and environmental variables. Results have shown that preliminary risk is correlated to, at least, seven sanitary and environmental variables, depending on flood influence area;and there are significant correlations observed in the rainy season interval [probability or significance (p) 0.05]. In conclusion, PRF is higher in the rainy season, but it is spatially influenced by the elevation of terrain, number of flooding points, drainage typology and Environmental Salubrity Index (ESI) of neighborhoods, which directly affect the water quality in nearby groundwater wells (Total Coliforms, nitrate (NO3) and ammonia (NH3)). However, this influence can eventually significantly change in the dry season.

关键词： drainage system Environmental Salubrity Index Groundwater GIS

GIS Spatial-Temporal Modeling of Water systems in Greater Toronto Area, Canada

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Journal of China University of Geosciences 2004年第3期15卷 275-282页

作者： ChengQiuming ZhangGeorge LuCindy KoConnie DepartmentofEarthandAtmosphericScience DepartmentofGeographyYorkWniversityTorontoOnt.M3J1P3Canada OntarioMinistryofEnvironment TorontoCanada

Modeling landscape with high-resolution digital elevation model (DEM) in a geographic information system can provide essential morphological and structural information for modeling surface processes such as geomorphologic process and water systems. This paper introduces several DEM-based spatial analysis processes applied to characterize spatial distribution and their interactions of ground and surface water systems in the Greater Toronto Area (GTA), Canada. The stream networks and drainage basin systems were derived from the DEM with 30 m resolution and the regularities of the surface stream and drainage patterns were modeled from a statistical/multifractal point of view. Together with the elevation and slope of topography, other attributes defined from modeling the stream system, and drainage networks were used to associate geological, hydrological and topographical features to water flow in river systems and the spatial locations of artesian aquifers in the study area. Stream flow data derived from daily flow measurements recorded at river gauging stations for multi-year period were decomposed into 'drainage-area dependent' and 'drainage-area independent' flow components by two-step 'frequency' and 'spatial' analysis processes. The latter component was further demonstrated to relate most likely to the ground water discharge. An independent analysis was conducted to model the distribution of aquifers with information derived from the records of water wells. The focus was given on quantification of the likelihood of ground water discharge to river and ponds through flowing wells, springs and seepages. It has been shown that the Oak Ridges Moraine (ORM) is a unique glacial deposit that serves as a recharge layer and that the aquifers in the ORM underlain by Hilton Tills and later deposits exposed near the steep slope zone of the ridges of ORM provide significant discharge to the surface water systems (river flow and ponds) through flowing wells, springs and seepages. Various statistics (cross- and auto-correlatio

关键词： GIS drainage system water flow precipitation flowing wells prediction.

Quantitative Geomorphological and Hydromorphometric Analysis of drainage Basins of As Sabriyah (Kuwait) Using GIS Techniques

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Journal of Geographic Information system 2021年第2期13卷 166-193页

作者： Adeeba Al-Hurban Fawziyah Al-Ruwaih Ahamd Al-Dughairi Earth and Environmental Sciences Department Faculty of Science Kuwait University Kuwait City Kuwait Department of Geography Faculty of Arabic Language and Social Studies Qassim University Burydah Kingdom of Saudi Arabia

A well-developed drainage network was carved in the study area in a hard calcretized and gypcretized gravelly sand of the Dibdibba Formation (Al-Rukham slope) in pluvial episodes in the post-pleistocene age, and is referred to be paleo-drainage due to the current witnessed aridity. This study aims to investigate the geomorphologic, morphometric, and stratigraphic characteristics of the paleo-drainage system and its role in recharging shallow aquifers. Morphometric analysis was accomplished using GIS and remote sensing techniques. Six vertical pit holes were dug across the area to investigate the stratigraphy and recharging capacity. The drainage system is composed of 10 closely spaced, subparallel, dendritic, elongated, and variant-sloped drainage basins with highest stream order of 5. Water flows NE from Al-Rukham ridge’s crest (60 m a.m.s.l.) downstream in Khor Al-Subiyah coastal flat. The bed rock’s hard resistant nature lowered its infiltration and recharging capacity to the shallow aquifer, whereas the coarse-grained wadi fills deposits increased infiltration capacity of the surface sediments, but the water percolation chance is limited as it eventually directed seaward by the same-directed general topography resulting in limiting potential recharge to the shallow aquifers. This is suggested to oppose the salt water intrusion and thus enhance fresh water quality.

关键词： drainage system Morphometric Characteristics Wadi Fill Deposits Dendritic Pattern Calcretic Gypretic