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A Simulated Test of Algal Influence of Formation and Deposition of Phosphates

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 417-426页

作者： Liu Zhili Liu Xuexian Fan Yigong Zhu Shixin department of Biology, Nanjing University Tianjin Institute of geology and Mineral Resources,Chinese Academy of geological Sciences department of Biology Nan jing University China

This paper deals with a simulated test of biogenic mineralization made with a blue-green alga species,Spirulina platensix. The data in the experiment were recorded by a computerized surveying system. The influ-ence of algae on the accumulation of phosphorus by changing their microenvironment to promote the forma-tion and deposition of phosphate was studied. The results show that the pH value of cultural liquor rose up to 10 and the redox potential (Eh) may dropby 100-200 mV during the algal logarithmic growth stage, and the cultrual liquor was changed into a mediumwith a weakly reducing condition. At the end of the logarithmic growth stage white deposits of Na_2Ca(CO_3)_2·5H_2O and Ca_2Mg (PO_4)_2·2H_2O were formed on the floor of cultural containers. The test presented a wduableevidence for the theory of biogenic mineralization.

关键词： In A Simulated Test of Algal Influence of Formation and Deposition of Phosphates Test

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山区公路隧道建设灾害预防与控制技术

长沙交通学院学报 2009年第1期25卷 45-52页

作者：李夕兵宫凤强李地元张伟黄炳仁中南大学资源与安全工程学院湖南长沙410083 Rock Mechanics Laboratory Swiss Federal Institute of Technology Lausanne department of geology and Mineral Resources engineering Norwegian University of Science and Technology

以典型山区公路隧道为工程背景,对山区公路隧道在开挖施工、建设过程中所遇到的工程灾害问题进行了系统研究,并对此进行了概述.主要包括4个方面:①建立了公路隧道围岩分级的距离判别分析模型;②研制了能模拟深埋隧道围岩受力情况的组合... 详细信息

以典型山区公路隧道为工程背景,对山区公路隧道在开挖施工、建设过程中所遇到的工程灾害问题进行了系统研究,并对此进行了概述.主要包括4个方面:①建立了公路隧道围岩分级的距离判别分析模型;②研制了能模拟深埋隧道围岩受力情况的组合加载装置,并利用突变理论对洞室屈曲岩爆的发生机理进行了研究;③利用有限差分软件FLAC3D,对富水地段公路隧道进行三维流固耦合分析,在此基础上提出了包括粘贴式集排水系统在内的一系列针对性很强的渗漏水控制技术,并成功地在常吉高速公路相关隧道顺利实施;④提出了推断岩土力学参数概率密度函数的新方法,并对隧道衬砌可靠度进行了相关分析.这些研究内容各自独立又紧密联系,能够在一定程度上对隧道的安全施工和长效运营提供系统的技术保障.

关键词：公路隧道围岩分级岩爆组合加载渗漏水衬砌可靠度

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Imposing Active Sources during High-Frequency Passive Surface-Wave Measurement

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engineering 2018年第5期4卷 685-693页

作者： Feng Cheng Jianghai Xia Chao Shen Yue Hu Zongbo Xu Binbin Mi Subsurface Imaging and Sensing Laboratory Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China School of Earth Sciences Zhejiang University Hangzhou 310027 China School of Measurement and Testing engineering China Jiliang University Hangzhou 310018 China department of Geosciences Boise State University Boise ID 83725 USA

Passive surface-wave utilization has been intensively studied as a means of compensating for the short-age of low-frequency information in active surface-wave measurement, In general, passive surface-wave methods cannot provide phase velocities up to several tens of hertz; thus, active surface-wave methods are often required in order to increase the frequency range, To reduce the amount of field work, we pro-pose a strategy for a high-frequency passive surface-wave survey that imposes active sources during con-tinuous passive surface-wave observation; we call our strategy ＂mixed-source surface-wave （MSW） measurement,＂ Short-duration （within 10 min） passive surface waves and mixed-source surface waves were recorded at three sites with different noise levels： namely, inside a school, along a road, and along a railway, Spectral analysis indicates that the high-frequency energy is improved by imposing active sources during continuous passive surface-wave observation, The spatial autocorrelation （SPAC） method and the multichannel analysis of passive surface waves （MAPS） method based on cross-correlations were performed on the recorded time sequences, The results demonstrate the flexibility and applicability of the proposed method for high-frequency phase velocity analysis, We suggest that it will be constructive to perform MSW measurement in a seismic investigation, rather than exclusively performing either active surface-wave measurement or passive surface-wave measurement,

关键词： Passive surface wave Active surface wave High frequency Mixed-source surface wave Spatial autocorrelation Multichannel analysis of passive surface waves

Machine learning of element geochemical anomalies for adverse geology identification in tunnels

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Journal of Earth Science 2024年

作者： Ruiqi Shao Peng Lin Zhenhao Xu Fumin Liu Yilong Liu School of Qilu Transportation， Shandong University State Key Laboratory for Tunnel engineering Jinan Institute of Geotechnical and Underground engineering， Shandong University

geological analysis， despite being a long-term method for identifying adverse geology in tunnels， has significant limitations due to its reliance on empirical analysis. The quantitative aspects of geochemical anomalies associated with adverse geology provide a novel strategy for addressing these limitations. However， statistical methods for identifying geochemical anomalies are insufficient for tunnel engineering. In contrast， data mining techniques such as machine learning have demonstrated greater efficacy when applied to geological data. Herein， a method for identifying adverse geology using machine learning of geochemical anomalies is proposed. The method was identified geochemical anomalies in tunnel that were not identified by statistical methods. We by employing robust factor analysis and self-organizing maps to reduce the dimensionality of geochemical data and extract the anomaly elements combination (AEC). Using the AEC sample data， we trained an isolation forest model to identify the multi-element anomalies， successfully. We analyzed the adverse geological features based the multi-element anomalies. This study， therefore， extends the traditional approach of geological analysis in tunnels and demonstrates that machine learning is an effective tool for intelligent geological analysis. Correspondingly， the research offers new insights regarding the adverse geology and the prevention of hazards during the construction of tunnels and underground engineering projects.

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Creation of Data Specification for Geospatial Information in Albania on the Theme:“geology”

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Journal of Environmental Science and engineering(B) 2021年第2期10卷 55-64页

作者： Gëzim Tola Mikel Millja Bardhyl Muceku Standards of Geoinformation Sector State Authority for Geospatial Information(ASIG)Rr.“Papa Gjon PaliⅡ”Nr.3Kati 2Tirana 1001Albania department of Earth Sciences Faculty of Geology and MiningRruga e ElbasanitNr.1TiranaAlbania

The development of technology and the demands of groups of interest for standardized digital geospatial information are increasing *** necessity for referred geospatial information,according to a Referencing Coordinating System and European Standards,through a national GIS(Geographic Information System)system,requires a decision making of national and institutional ***(State Authority for Geospatial Information)is the institution that administrates,implements,and maintains the NSDI(National Spatial Data Infrastructure).It is calculated that 80%of decision-making by public or private institutions uses geospatial data with a well-organized structure that enables ***,standardization of geospatial data by topic is one of the main objectives of implementing the NSDI in *** is a complex task for the standard and the harmonization of geospatial data,which can be a good opportunity for professional *** study shows in detail the methodology for the creation and implementation of data specification for geospatial information in Albania on the theme:geology,adoption of the technical specification of the INSPIRE directive as well as the importance of ASIG as an institution that builds and maintains NSDI in Albania.

关键词： Geospatial data GIS ASIG INSPIRE NSDI

Distribution and Pollution Assessment by Index of Geoaccumulation about the Heavy Metals in Sediments of Dexing Copper Mine Rainwater Network

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Distribution and Pollution Assessment by Index of Geoaccumul...

Optimizing the Interpretation of Sub-surface Resistivity in Relation with Borehole Productivity in Basement Area Applied to Seno Province （Burkina Faso）

作者： Xueping Huang Qiang Fu Jianhua Wang department of Civil engineering and Architecture Nanchang Institute of Technology Intra-organization Service Center Department of Agriculture and Rural Affairs of Jiangxi Province Shenzhen Environmental engineering Technology Center Co. Ltd

The sediment in the rainwater pipe network in Dexing copper mine area was selected as the research *** ICP-MS to determinate the 6 kinds of heavy metals content in sediments at 16 samplings,the measured data were analyzed in comparison with the national standard for soil environmental quality,and the geological accumulation exponential method was used for evaluating the heavy metals in *** results showed that the content of Cu and as exceeded the national grade III soil quality standard in many areas,but the regional difference was not *** content of Cd exceeds the national grade III soil quality standard in some regional samples,and its spatial distribution features were very *** total amount of Cr,Zn and Pb was lower than the national grade III soil quality *** was found that the pollution degree of Cd was the most serious,followed by Cu and As,Cr,Zn and Pb with the assessment by Index of geoaccumulation.

关键词： Dexing copper mine rainwater pipe sediment heavy metal pollution risk evaluation Index of geoaccumulation

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Journal of Environmental Science and engineering(B) 2016年第12期5卷 563-580页

作者： Mahamadou Koita Hamma Fabien Yonli Delwende Guy Christian Nikiema department of Civil engineering and Hydraulics the International Institute for Water and Environmental Engineering BP 594 Ouagadougou 01 Burkina Faso department of Physics and Environmental Chemistry the University of Ouaga 1 Pr Joseph K1 ZERBO BP 7021 Ouagadougou 03Burkina Faso

This study aims at identifying possible correlations between shapes, types of geophysical anomalies and borehole productivity according to geological and hydrogeotogical contexts. The methodology adopted was a two-pronged one--the first step sought to：（1） interpret the electrical resistivity values from horizontal profiling and vertical electrical sounding implemented in Seno province that preceded the drilling of 513 boreholes; （ii） interpret data from pumping tests carried out on boreholes having a discharge superior to 1 m3/h （＂positive borehole＂） by using Cooper-Jacob＇s method. In the second step, according to geology, authors tried to identify possible correlations between each of the qualitative geophysical parameters： ~shape of anomaly〉〉, tttype of anomaly〉〉 and ~〈type curve〉〉 on the one hand, and hydrogeological parameters such as discharge, alteration thickness, transmissivity and saturated level on the other. The results of this study have shown that the chances of having a positive borehole in Seno province are higher when the type of anomaly is TCC （80%）, shape of anomaly is ＂W＂ and when type curve is ＂H＂（80%） for all geological formations. Granitic formations are those that record higher discharges while schists record high transmissivity values.

关键词： Basement rocks sub-surface resistivity borehole anomaly productivity Seno province Burkina.

Modeling dissolved organic carbon in temperate forest soils:TRIPLEX-DOC model development and validation

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Modeling dissolved organic carbon in temperate forest soils:...

高砷地下水系统中非岩石圈源的沉积物砷异常（英文）

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： H.Wu C.Peng T.R.Moore D.Hua C.Li Q.Zhu M.Peichl M.A.Arain Z.Guo Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Science department of Biology Sciences Institute of Environment Sciences University of Quebec at Montreal Laboratory for Ecological Forecasting and Global Change College of Forestry Northwest A & F University department of Geography and Global Environmental and Climate Change Centre McGill University Center for Climate Research University of Wisconsin-Madison Institute for the study of Earth Ocean and Space University of New Hampshire department of Forest Ecology and Management Swedish University of Agricultural Sciences School of Geography and Earth Sciences and McMaster Centre for Climate Change McMaster University

Even though dissolved organic carbon(DOC) is the most active carbon(C) cycling in soil organic carbon(SOC) pools, it receives little attention from the global C budget. DOC fluxes are critical to aquatic ecosystem inputs and contribute to the C balance of terrestrial ecosystems, but few ecosystem models have attempted to integrate DOC dynamics into terrestrial C cycling. This study introduces a new process-based model, TRIPLEX-DOC, that is capable of estimating DOC dynamics in forest soils by incorporating both ecological drivers and biogeochemical processes. TRIPLEXDOC was developed from Forest-DNDC, a biogeochemical model simulating C and nitrogen(N) dynamics, coupled with a new DOC process module that predicts metabolic transformations,sorption/desorption, and DOC leaching in forest soils. The model was validated against field observations of DOC concentrations and fluxes at white pine forest stands located in southern Ontario, Canada. The model was able to simulate seasonal dynamics of DOC concentrations and the magnitudes observed within different soil layers, as well as DOC leaching in the age sequence of these forests. Additionally,TRIPLEX-DOC estimated the effect of forest harvestingon DOC leaching, with a significant increase following harvesting,illustrating that land use change is of critical importance in regulating DOC leaching in temperate forests as an important source of C input to aquatic ecosystems.

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Science Bulletin 2023年第15期 1616-1620页

作者：韩龙孙雨芹李曾一段艳华韩双宝张海龙赵美训郑焰 State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and Engineering Southern University of Science and Technology Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and Engineering Southern University of Science and Technology School of Biological Sciences University of East Anglia Center for Hydrogeology and Environmental geology Survey China Geological Survey Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology

世界卫生组织认定无机砷为危害全球公众健康的十大化学物质之一.学术界普遍认为地下水中无机砷源自地层,非人为污染所致,从基岩或经风化搬运形成的松散沉积物含水层中释放进入地下水,但鲜见岩石圈砷异常的报道.本研究对银川平原高砷地...

世界卫生组织认定无机砷为危害全球公众健康的十大化学物质之一.学术界普遍认为地下水中无机砷源自地层,非人为污染所致,从基岩或经风化搬运形成的松散沉积物含水层中释放进入地下水,但鲜见岩石圈砷异常的报道.本研究对银川平原高砷地下水系统中沉积物的物源和砷源开展了定量溯源,构建了基于粒度、无机化学参数(Fe/Al和Si/Al比)及有机碳-13和碳-14的无机物源、有机物源及砷源端元模型,发现沉积物中存在贺兰山和黄河等岩石圈源之外的“过量砷”;结合环青藏高原多个高砷地下水区文献数据分析,发现可通过As/Fe摩尔比大于0.0003识别沉积物砷异常.鉴于砷在地表-地下水交互界面的氧化次生富集,提出该异常源自水圈,可循环进入地下水“再生”.这可解释全球高砷地下水冲洪积平原上游地区无显著岩石圈砷异常之谜.

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