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Journal of Earth Science 2014年第3期25卷 598-604页

作者： Chen Su Zongyu Chen Jiang Chen Yuhong Fei Jingsheng Chen Baoqian Duan Institute of hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

The deformation of aquitard is the main contribution to land subsidence in the North China Plain, and the water released from aquitard compaction may be a large portion of the exploited groundwater. In this study, the consolidation test was employed to understand the mechanics on the drainage and deformation of aquitard. The results suggested the strain of aquitard mainly resulted from the difference of hydraulic head between aquifers. And it was decreased with depth of aquitard at the same hydrodynamic pressure. In contrast with the interbed within aquifers, the aquitard was deformable when it was compressed. The weakly bound water was significantly released when the void ratio was about 0.44–0.45, and the EC of water released from the aquitard was decreased with the compacting process. The data from the consolidation test suggested that the pumping of groundwater from aquifer III might be less contribution to the land subsidence with respect to other aquifers in the future.

关键词： Quaternary aquifer clay consolidation test double layer land subsidence.

Distribution of Arsenic in Sewage Irrigation Area of Pearl River Delta,China

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Journal of Earth Science 2011年第3期22卷 396-410页

作者：黄冠星孙继朝张英荆继红张玉玺刘景涛 The Institute of hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

The aim of the present work is to investigate the distribution of arsenic（As） in sewage ir-rigation area,to deduce the migration and transformation mechanism of As in soil and groundwater,and to infer the source of As in soil and *** study is carried out in a sewage irrigation area of the Pearl River Delta,*** water samples,soil samples,and groundwater samples from sewage irrigation area were analyzed for As and other *** contents in water samples were analyzed by hydride generation-atomic fluorescence spectroscopy,and As fractionation in soil samples was extracted using a seven-step sequential extraction method according to a seven fraction scheme：water soluble,ion exchangeable,bound to carbonate,weakly bound to organic matter,associ-ated with oxides of iron（Fe） and manganese（Mn）,strongly bound to organic matter,and the residual *** water has content of As up to 16.8 μg/L in the study *** has enriched As due to the irrigation of soil with waste water,and the total content of As in soil is about 0.7 times higher than the background *** extraction method reveals that the mean content of residual fraction in soil is more than 70%,releasable fraction（weakly organic fraction,Fe-Mn oxide fraction,and car-bonate fraction） is about 20%-30%,whereas strongly organic and mobile fractions（water soluble and ion exchangeable） are within 0.2%.In the soil profile,the contents of water soluble,ion exchangeable,and carbonate fraction decrease with the depth,whereas the contents of other fractions are irregular with the *** correlation analysis,it is concluded that water soluble fraction is easy to change into ion exchangeable and carbonate fraction,ion exchangeable fraction is easy to change into carbon-ate and Fe-Mn oxide fraction,and carbonate fraction is easy to change into weakly organic and Fe-Mn oxide fraction in the soil of study *** matter and（hydr）oxides of Fe and aluminium（Al） in soil play an imp

关键词： arsenic sewage irrigation area soil groundwater fraction.

A numerical study of non-Darcy flow in EGS heat reservoirs during heat extraction

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Frontiers in Energy 2019年第3期13卷 439-449页

作者： Wenjiong CAO Wenbo HUANG Guoling WEI Yunlong JIN Fangming JIANG laboratory of Advanced Energy Systems Guangdong Key Laboratory of New and Renewable Energy Research and DevelopmentCAS Key Laboratory of Renewable EnergyGuangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China Guangdong hydrogeology Battalion Guangzhou 510510China

Underground non-Darcy fluid flow has been observed and investigated for decades in the petroleum industry. It is deduced by analogy that the fluid flow in enhanced geothermal system (EGS) heat reservoirs may also be in the non-Darcy regime under some conditions. In this paper, a transient 3D model was presented, taking into consideration the non-Darcy fluid flow in EGS heat reservoirs, to simulate the EGS long-term heat extraction process. Then, the non-Darcy flow behavior in water- and supercritical CO2 (SCCO2)-based EGSs was simulated and discussed. It is found that non-Darcy effects decrease the mass flow rate of the fluid injected and reduce the heat extraction rate of EGS as a flow resistance in addition to the Darcy resistance which is imposed to the seepage flow in EGS heat reservoirs. Compared with the water-EGS, the SCCO2-EGS are more prone to experiencing much stronger non-Darcy flow due to the much larger mobility of the SCCO2. The non-Darcy flow in SCCO2- EGSs may thus greatly reduce their heat extraction performance. Further, a criterion was analyzed and proposed to judge the onset of the non-Darcy flow in EGS heat reservoirs. The fluid flow rate and the initial thermal state of the reservoir were taken and the characteristic Forchheimer number of an EGS was calculated. If the calculated Forchheimer number is larger than 0.2, the fluid flow in EGS heat reservoirs experiences non-negligible non-Darcy flow characteristic.

关键词： enhanced geothermal system non-Darcy flow heat extraction Reynolds number Forchheimer number

Sustainability of Intensively Exploited Aquifer Systems in the North China Plain: Insights from Multiple Environmental Tracers

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Journal of Earth Science 2014年第3期25卷 605-611页

作者： Aina Su Zongyu Chen Jun Liu Wen Wei Institute of hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

Environmental tracers are proving to be a unique tool for assessing groundwater sustainability, such as characterization of recharge, identification of pathways and sources of contaminants, and prediction of groundwater change in response to excessive abstraction. This paper helps to better understand the groundwater sustainability in the Quaternary aquifer from the tracer data in the North China Plain. Relatively modern ground waters occur in the piedmont plain with 3H-3He age less than 40 a within a depth 100 m. These ground waters are mainly recharged from the local precipitation and irrigation return. The recharge rate estimated by tracers is in the range of 0.24 to 0.32 m/a. Paleowater which is dated from 10 000 a B.P. to more than 35 000 a B.P. by radiocarbon dating is found in highly-confined portions of Quaternary aquifer systems. This indicates that water recharge took place during the past glacial period. The tracers have suggested a slow natural replenishment rates to the central plain. The aquifer has been overexploited currently. Some strategies that can be implemented to promote a sustainable groundwater supply are needed to implement in future.

关键词： sustainability groundwater exploited environmental tracer North China Plain.

Construction of Opening Regional Geological Hazards Risk Assessment System

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Construction of Opening Regional Geological Hazards Risk Ass...

Impacts of Human Activities on the Occurrence of Groundwater Nitrate in an Alluvial Plain: A Multiple Isotopic Tracers Approach

2011 International Conference on Photonics, 3D-Imaging, and Visualization

作者： ZHU Jixiang ZHANG Lizhong ZHOU Xiaoyuan Wang Qian Institute of hydrogeology and Environmental Geology CAGS

ISBN: (纸本)9780819488473

It’s the basis of the regional geological hazard assessment of regional geological hazard risk research, and the result can provide foundation for planning of land and resources, selection of important project site, controlling, monitoring, and forecasting geological disaster, developing contingency measures for disaster, and environmental protection. With the development of GIS technology, methods and models of regional geological hazard assessment have made great progress, it gradually change from the qualitative and semi-quantitative to quantitative, systematic, spatial management. This paper proposed a user-oriented, method- oriented, categoryoriented system of regional geological hazards risk assessment through discusses the key points of geological hazards risk assessment, and the requirements of geological disaster evaluation system development today. The new evaluation system fit varieties types of geological disaster evaluation in different areas, and it owns a very important practical significance.

关键词： GIS geological hazard risk assessment expected loss

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Journal of Earth Science 2013年第1期24卷 111-124页

作者：庞忠和袁利娟黄天明孔彦龙刘记来李义曼 Key laboratory of Engineering Geomechanics Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences China hydrogeology and Engineering Geology Team of Beijing

Nitrate pollution is a severe problem in areas with intensive agricultural activities. This study focuses on nitrate occurrence and its constraints in a selected alluvial fan using chemical data combined with environmental isotopic tracers （180, 3H, and lSN）. Results show that groundwater nitrate in the study area is as high as 258.0 mg/L （hereafter NO3） with an average of 86.8 mg/L against national drinking water limit of 45 mg/L and a regional baseline value of 14.4 mg/L. Outside of the riparian zone, nitrate occurrence is closely related to groundwater circulation and application of chemical *** groundwater nitrate is found in the re- charge area, where nitrate enters into ground- water through vertical infiltration, correspond- ing to high 3H and enriched 1SO in the water. In the riparian zone, on the contrary, the fate of groundwater nitrate is strongly affected by groundwater level. Based on two sampling tran- sects perpendicular to the riverbank, we found that the high level of nitrate corresponds to the deeper water table （25 m） near the urban center, where groundwater is heavily *** nitrate is much lower （〈12.4 mg/L） at localities with a shallow water table （5 m）, which is likely caused by denitrification in the aquifer.

关键词： nitrate alluvial plain environmental isotope fertilizer application groundwater exploitation.

Changes of Precipitation Infiltration Recharge in the Circumstances of Coal Mining Subsidence in the Shen-Dong Coal Field,China

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 993-1003页

作者： ZHANG Fawang SONG Yaxin ZHAO Hongmei HAN Zhantao WANG Dong Institute of hydrogeology and Environmental Geology CAGS Institute of Karst Geology CAGS/Karst Dynamics LaboratoryMinistry of Land and Resources Non-ferrous Metal Geological Survey Center

Coal mining subsidence is a universal environmental-geological problem in mining areas. By selecting the Shen-Dong coal mining subsidence area as the research field, this paper studies the changes in precipitation infiltration recharge in the circumstances of coal mining subsidence by means of field geological investigation and laboratory simulation experiments, which is expected to provide a scientific basis for eco-environmental restoration in the mining area. The results indicate that at the unstable stage of subsidence, three types of subsidence in the Shen-Dong mining area have positive effects on the precipitation infiltration recharge, and the type of full-thickness bedrock subsidence has the greatest influence. In the stable stage of subsidence, the precipitation infiltration process after long- term drought and the moisture migration in the aeration zone undergo three different stages： evaporation-infiltration before precipitation, infiltration-upward infiltration-infiltration during precipitation and evaporation-infiltration after precipitation. During a heavy rainfall infiltration process, the wetting front movement in fine sand, coarse sand and dualistic structure of fine-coarse sand consists of two stages： the stage of wetting front movement during precipitation, in which the wetting front movement distance has linear relationship with the depth, and the stage of wetting front movement after precipitation, in which the wetting front movement distance has the power function relationship with the depth. The wetting front movement velocity is influenced by the rainfall amount and the lithology in the aeration zone. However, as the depth increases, the movement velocity will decay exponentially.

关键词： precipitation infiltration simulation coal mining subsidence Shen-Dong mining area

Influence of Rain on Tetrachloroethylene's Multiphase Migration in Soil

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Journal of Earth Science 2015年第3期26卷 453-460页

作者： Yong Qian Jingli Shao Zhaoji Zhang Yuhong Fei Chunxiao Wang Xiangxiang Cui Suhua Meng School of Water Resources & Environment China University of Geosciences The Institute of hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Hebei Key laboratory of Groundwater Remediation

For the increasingly serious soil and groundwater pollution by volatile organic compounds, tetrachloroethylene（PCE） was selected as the research object in this study. With the in-situ soil column physical simulation experiments, migration law of PCE in soil under rain conditions was studied by monitoring precipitation and soil parameter as well as sampling and analyzing soil and soil gas, and influence of rain on the multiphase migration process of PCE was preliminarily discussed. Research shows that migrations of PCE and soil moisture were not synchronous, and the rate of the former was speeded up by the latter caused by rain. Preliminary analysis indicates that migration of volatile chlorohydrocarbon in soil was not only driven by soil moisture, but also controlled by the nature of volatility of their own, that is to say, volatilization into gas phase was an important way of migrating and diffusing in pore medium, and the rate of migration and diffusion of gaseous PCE was faster than that of solid, resulting in more abroad distribution of gas phase than that in solid phase.

关键词： volatile organic pollution soil water migration tetrachloroethylene(PCE) gas phase

Aquifer hydraulic conductivity prediction via coupling model of MCMC-ANN

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Journal of Groundwater Science and Engineering 2021年第1期9卷 1-11页

作者： GUI Chun-lei WANG Zhen-xing MA Rong ZUO Xue-feng The Institute of hydrogeology and Environmental Geology Key Laboratory of Groundwater Sciences and EngineeringMNRShijiazhuang 050061China

Grain-size distribution data,as a substitute for measuring hydraulic conductivity(K),has often been used to get K value *** grain-size distribution data of 150 sets of samples being input data,this study combined the Artificial Neural Network technology(ANN)and Markov Chain Monte Carlo method(MCMC),which replaced the Monte Carlo method(MC)of Generalized Likelihood Uncertainty Estimation(GLUE),to establish the GLUE-ANN model for hydraulic conductivity prediction and uncertainty *** means of applying the GLUE-ANN model to a typical piedmont region and central region of North China Plain,and being compared with actually measured values of hydraulic conductivity,the relative error ranges are between 1.55%and 23.53%and between 14.08%and 27.22%respectively,the accuracy of which can meet the requirements of groundwater resources *** global best parameter gained through posterior distribution test indicates that the GLUEANN model,which has satisfying sampling efficiency and optimization capability,is able to reasonably reflect the uncertainty of hydrogeological ***,the influence of stochastic observation error(SOE)in grain-size analysis upon prediction of hydraulic conductivity was discussed,and it is believed that the influence can not be neglected.

关键词： Grain-size distribution Hydraulic conductivity ANN GLUE MCMC Stochastic Observation Error(SOE)

Chemical fractions and potential mobility of lead in soils irrigated by sewage in Pearl River Delta,South China

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Journal of Central South University 2012年第9期19卷 2620-2626页

作者：黄冠星陈宗宇孙继朝刘景涛张玉玺王金翠 Institute of hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

The chemical fractions,i.e.,water soluble(WS),exchangeable(Ex),carbonate(Car),weakly organic(WO),Fe-Mn oxide(FMO),strongly organic(SO),residual(Res) fraction,of Pb in irrigated soils in South China were investigated by a modified Tessier sequential extraction *** results show that the chemical fraction of Pb in soil is mainly the Res fraction and followed by FMO fraction,and the WS,WO,FMO,and SO fractions in topsoils(0-10 cm) are higher than those in subsoils(30-40 cm).The sum of contents of WS and Ex fractions(SWE) in topsoils is significantly positively related with that in subsoils,indicating the strong mobility of Pb in WS and Ex fractions in soils,and the SWE in soils is higher than the German trigger value for the transfer path soil-plant,indicating the high bioavailability of Pb in soils of this ***,SWE and the ratio of WS and Ex fractions(RWE) to the sum of all fractions generally decrease with the soil depth in soil profile and the RWE in soil profile is lower than 0.5%,indicating the low pollution risk for Pb in *** addition,soil particles,pH and Fe2O3 play an important role in the impact of mobility and chemical fractions of Pb in soils.

关键词： chemical fractions mobility lead irrigated soil soil profile