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Mobility and dynamic erosion process of granular flow:insights from numerical investigation using material point method

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Journal of Mountain Science 2024年第8期21卷 2713-2738页

作者： yu Fangwei su lijun li Xinpo ZHAO yu Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of chinese academy of sciences Beijing 100049China China-Pakistan Joint Research Center on Earth sciences Islamabad 45320Pakistan Center for Excellence in Tibetan Plateau Earth sciences Chinese Academy of SciencesBeijing 100101China College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China

In order to understand the dynamics of granular flow on an erodible base soil,in this paper,a series of material point method-based granular column collapse tests were conducted to investigate numerically the mobility and dynamic erosion process of granular flow subjected to the complex settings,i.e.,the aspect ratio,granular mass,friction and dilatancy resistance,gravity and presence of water.A set of power scaling laws were proposed to describe the final deposit characteristics of granular flow by the relations of the normalized run-out distance and the normalized final height of granular flow against the aspect ratio,being greatly affected by the complex geological settings,e.g.,granular mass,the friction and dilatancy resistance of granular soil,and presence of water in granular *** index of the coefficient of friction of granular soil was defined as a ratio of the target coefficient of friction over the initial coefficient of friction to quantify the scaling extent of friction change(i.e.,friction strengthening or weakening).There is a characteristic aspect ratio of granular column corresponding to the maximum mobility of granular flow with the minimum index of the apparent coefficient of *** index of the repose coefficient of friction of granular flow decreased gradually with the increase in aspect ratio because higher potential energy of granular column at a larger aspect ratio causes a larger kinetic energy of granular soil to weaken the friction of granular soil as a kind of velocity-related friction *** increase in granular mass reduces gradually the indexes of the apparent and repose coefficients of friction of granular soil to enhance the mobility of granular *** mobility of granular flow increases gradually with the decrease in friction angle or increase in dilatancy angle of granular ***,the increase of gravity accelerates granular flow but showing the same final deposit profile without any dependence on ***

关键词： Column collapse Granular flow Granular soil Material point method Mobility Numerical tests

Electrical Characteristics of Tangjiawan Landslide in lixian, Sichuan

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Applied Geophysics 2024年第3期21卷 549-563,619页

作者： Bin li Qiang Xu Qiang Cheng Tian-Xiang liu Jian-hua yu yu-jie su Feng Wang Sichuan Highway Planning SurveyDesign and Research Institute Ltd.SichuanChengdu 610041China Chengdu University of Technology State Key Laboratory of Geohazard Prevention and Geoenvironment ProtectionSichuanChengdu 610059China

A wide range of terrain features and landforms,which are exemplified by intricate geological formations and diverse rock compositions,are found in the western mountainous regions of *** areas frequently encounter geological *** one of the natural disasters,landslides lead to considerable loss of human life and *** mitigation of the losses caused by landslide disasters,a necessary measure for disaster prevention and mitigation involves conducting detailed investigations and monitoring of landslides,which is also the cornerstone of landslide *** study compares and analyzes the feasibility of the magnetotelluric detection method for landslides using the results of engineering geological surveys and landslide *** study aims to address the scientific problem of the validity of using magnetotelluric methods to detect landslide development *** Tangjiawan landslide signal on the left side of the K94+000~K94+145 section of the Wenma Expressway is analyzed by employing engineering geological survey,magnetotelluric detection,landslide monitoring,landslide analysis,and other *** results provide the static electrical characteristics of lithology,structure,and groundwater,as well as the dynamic electrical characteristics of landslide *** study focuses on analyzing the relationship between the methods of magnetotelluric detection and engineering geological surveys and the results of landslide *** workflow and methods for data collection,processing,inversion,interpretation,and analysis using the magnetotelluric method to detect the dynamic development process of landslides are presented in the *** conclusions indicate a strong correlation between the dynamic changes in magnetotelluric wave impedance with the surface displacement of landslides and the dynamic changes in *** use of the magnetotelluric method for landslide detection and monitoring is a fe

关键词： Landslide Magnetotelluric method Geophysics Engineering geology Landslide Monitoring

生物体中氨基酸单体碳稳定同位素测试方法研究

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分析测试学报 2024年第3期43卷 447-454页

作者：梁建鑫尹希杰苏静林锡煌李玉红自然资源部第三海洋研究所分析测试中心福建厦门361005 中国地质调查局舟山海洋地质灾害野外科学观测研究站山东青岛266237

氨基酸作为蛋白质的基本组成单位,是重要的生命物质,其单体碳同位素研究在生物地球化学、生态学、生物体代谢和环境科学等领域具有重要意义。该文优化了海参和海藻氨基酸提取和纯化流程,通过N新戊酰基-O-异丙酯(NPP)方法衍生化后,分别... 详细信息

氨基酸作为蛋白质的基本组成单位,是重要的生命物质,其单体碳同位素研究在生物地球化学、生态学、生物体代谢和环境科学等领域具有重要意义。该文优化了海参和海藻氨基酸提取和纯化流程,通过N新戊酰基-O-异丙酯(NPP)方法衍生化后,分别用气相色谱-质谱(GC-MS)和气相色谱-燃烧-同位素比值质谱(GC-C-IRMS)测试其浓度和碳同位素组成。结果显示,15种氨基酸单体的分离效果较好,回收率为46.4%~96.3.,各氨基酸在1.0~16.0µmol/L范围内线性关系良好(r^(2)为0.987~0.999)。15种氨基酸单体衍生物δ^(13.C值的标准偏差均小于0.3.‰(n=10),在0.6~2.0 mmol/L浓度范围内δ^(13.C的平均误差为±0.24‰,方法检出限为0.6 nmol。海参和海藻样品各氨基酸单体δ^(13.C值的范围分别为-3..10‰~-8.58‰和-3..53.~-13.76‰,标准偏差均在0.3.‰以内,可满足生物体氨基酸单体碳同位素的测试精度需求。

关键词：气相色谱-燃烧-同位素比值质谱(GC-C-IRMS) N-新戊酰基-O-异丙酯(NPP) 氨基酸碳稳定同位素

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我国石墨资源供需平衡预测

地质论评 2024年第S1期70卷 109-110页

作者：吴琪吴初国李政苏宇陈从喜王文利自然资源部信息中心北京100812 中国非金属矿工业协会北京100831

石墨具有耐高温性、抗热震性,导电、导热性好,化学性质稳定,能耐酸、耐碱和耐有机溶剂的腐蚀。石墨广泛应用在原子能工业、新材料产业等新兴技术领域。石墨是一种优秀的中子减速剂,被广泛应用于原子反应堆。其中,铀—石墨反应堆是最为... 详细信息

石墨具有耐高温性、抗热震性,导电、导热性好,化学性质稳定,能耐酸、耐碱和耐有机溶剂的腐蚀。石墨广泛应用在原子能工业、新材料产业等新兴技术领域。石墨是一种优秀的中子减速剂,被广泛应用于原子反应堆。其中,铀—石墨反应堆是最为常见和广泛应用的原子反应堆类型之一。

关键词：石墨勘探开发供需形势中国

Enrichment characteristics and exploration directions of deep shale gas of Ordovician-Silurian in the Sichuan Basin and its surrounding areas,China

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Petroleum Exploration and Development 2022年第4期49卷 744-757页

作者： NIE Haikuan li Pei DANG Wei DING Jianghui suN Chuanxiang liU Mi WANG Jin DU Wei ZHANG {3. li Donghui su Haikun State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 102206China Sinopec Petroleum Exploration and Production Research Institute Beijing 102206China School of Earth sciences and Engineering Xi’an Shiyou UniversityXi’an 710300 CNPC Engineering Technology R&D Company limited Beijing 102206China Research Institute of Petroleum Exploration and Development Sinopec Jianghan Oilfield CompanyWuhan 430223China Sinopec East China Company Nanjing 210019China School of Energy Resources China University of GeosciencesBeijing 100083China

The enrichment characteristics of deep shale gas in the Ordovician Wufeng-Silurian Longmaxi formations in the Sichuan Basin and its surrounding areas are investigated through experiments under high temperature and high pressure,including petrophysical properties analyses,triaxial stress test and isothermal adsorption of methane experiment.(1)The deep shale reservoirs drop significantly in porosity and permeability compared with shallower shale reservoirs,and contain mainly free gas.(2)With higher deviatoric stress and axial strain,the deep shale reservoirs have higher difficulty fracturing.(3.Affected by structural location and morphology,fracture characteristics,geofluid activity stages and intensity,deep shale gas reservoirs have more complicated preservation conditions.(4)To achieve the commercial development of deep shale gas reservoirs,deepening geological understanding is the basis,and exploring reservoir simulation technology befitting the geological features is the key.(5)The siliceous shale and limestone-bearing siliceous shale in the Metabolograptus persculptus-Parakidograptus acuminatus zones(LM1-LM3.graptolite zones)are the high-production intervals for deep shale gas and the most favorable landing targets for horizontal *** water areas such as Jiaoshiba,Wulong,Luzhou and Changning with deep shale reservoirs over 10 m thickness are the most favorable areas for deep shale gas *** is recommended to carry out exploration and development practice in deep-water shale gas areas deposited deep with burial depth no more than 5000 m where the geological structure is simple and the shale thickness in the LM1-LM3.graptolite zone is greater than 10 *** is better to increase the lateral length of horizontal wells,and apply techniques including high intensity of perforations,large volume of proppant,far-field and near-wellbore diversions to maximize the stimulated deep reservoir volume.

关键词： deep shale gas enrichment conditions reservoir characteristics exploration direction Ordovician Wufeng Formation Silurian Longmaxi Formation Sichuan Basin

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存储式交通气象传感器数据采集系统

价值工程 2024年第18期43卷 156-158页

作者：姜波李薇丁宇超苏宇云南省交通规划设计研究院股份有限公司陆地交通地质灾害防治技术国家工程研究中心昆明650200

针对交通气象监测等领域对数据采集系统数据安全性与低成本的要求,设计一种基于存储式的气象数据采集系统,系统利用RS485自动收发电路采集前端气象传感器输出的气象监测区域采集时间、能见度、风速、风向、降水、气压、温度、相对湿度... 详细信息

针对交通气象监测等领域对数据采集系统数据安全性与低成本的要求,设计一种基于存储式的气象数据采集系统,系统利用RS485自动收发电路采集前端气象传感器输出的气象监测区域采集时间、能见度、风速、风向、降水、气压、温度、相对湿度等数据信号;以STM3.F103.控芯片进行数据处理,通过FatFS文件系统移植、SPI通信实现数据存储,提升对低信号区域气象灾害的监测和预警能力。试验结果表明,此系统能实时采集、解析、存储气象传感器数据,具有数据存储量大、兼容性强、成本低、稳定性高的优势,便于对交通气象传感器进行长期采集、存储、分析。

关键词：微控制器多通道存储式数据采集

Enrichment mechanism and resource potential of shale-type helium:A case study of Wufeng Formation-Longmaxi Formation in Sichuan Basin

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Science China Earth sciences 2023年第6期66卷 1279-1288页

作者： Haikuan NIE Quanyou liU Wei DANG Pei li Haikun su Hanyong BAO liang XIONG Zhujiang liU Chuanxiang suN peixian ZHANG State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Beijing 102206China Sinopec Key Laboratory of Shale Oil/Gas Exploration and Production Technology Beijing 102206China Petroleum Exploration and Production Research Institute SINOPECBeijing 102206China Institute of Energy Research Peking UniversityBeijing 100871China School of Earth sciences and Engineering Xi’an Shiyou UniversityXi’an 710065China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Research Institute of Exploration and Development Jianghan Oilfield CompanySINOPECWuhan 430223China Research Institute of Exploration and Development Southwest Oil&Gas CompanySINOPECChengdu 610041China Sinopec Exploration Company Chengdu 610041China Research Institute of Exploration and Development East China Petroleum&Gas BranchSINOPECNanjing 210019China

China’s helium resource is highly dependent on overseas ***-rich and U/Th-rich shale reservoirs generally contain helium,and although the helium content is low,the total reserve is ***,the effective development and utilisation of shale-type helium resources is a realistic way to improve the security of helium resources in *** this study,the generation mechanism,helium source and content,migration modes and pathways,controlling factors of enrichment,distribution pattern,and resource potential of the helium were analysed,using the Wufeng-Longmaxi shale in the Sichuan Basin and its ***,countermeasures were proposed for shale-type helium exploration and *** results show that the Wufeng-Longmaxi shale has a high content of U and Th and a good ability to generate *** helium is generated by a typical crustal source of helium and is characterised by self-generation,self-storage,and wide *** helium resource potential is a product of its content and the resources of the associated natural *** continuous supply of helium and effective preservation are the main geological factors that control the enrichment of shale-type *** preliminary evaluation results show that the reserves of helium in proven shale gas reserves are 10.8×10^(8)m^(3.in the Sichuan Basin and its periphery,where the extra-large helium fields are likely to be ***,0.0912×10^(8)m^(3.of helium was produced,along with the annual production of shale *** avoid the waste of helium and to improve the self-supply ability,it is suggested that research on the resource potential,enrichment mechanism,and distribution pattern of shale-type helium should be carried out as soon as possible,and helium extraction techniques for helium-bearing natural gas should be studied.

关键词： Shale Helium content Enrichment mechanism Resource potential Sichuan Basin

基于特征优选和机器学习的塔里木盆地东缘绿洲土壤镉元素含量预测及健康风险评价

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环境科学 2024年第8期45卷 4802-4811页

作者：刘靖宇李若怡梁永春刘磊尹芳唐塑何林森张毅长安大学地球科学与资源学院西安710054 中国地质调查局乌鲁木齐自然资源综合调查中心乌鲁木齐830057 中国自然资源航空物探遥感中心北京100083 长安大学土地工程学院西安710054 中国地质调查局西安矿产资源调查中心西安710100

土壤重金属污染对粮食安全、人类健康和土壤生态系统均造成重大威胁.基于塔里木盆地东缘典型绿洲区获取的644个土壤样品,运用多元线性回归(LR)、神经网络(BP)、随机森林(RF)、支持向量机(SVM)和基于径向基函数神经网络(RBF)方法构建土... 详细信息

土壤重金属污染对粮食安全、人类健康和土壤生态系统均造成重大威胁.基于塔里木盆地东缘典型绿洲区获取的644个土壤样品,运用多元线性回归(LR)、神经网络(BP)、随机森林(RF)、支持向量机(SVM)和基于径向基函数神经网络(RBF)方法构建土壤重金属预测模型,利用最优预测结果分析重金属污染的空间分布特征与健康风险.结果表明:①研究区ω(Cd)均值为0.14 mg·kg^(-1),是新疆土壤背景值的1.17倍,是区内土壤重金属污染的主要因子;区内成人和儿童Cd元素致癌风险系数均小于10~(-4),对人类无明显的长期健康风险影响.②对比5种反演模型的预测精度,RF模型验证集R^(2)值为0.763.,在5种模型中最大;且其RMSE、MAE和MBE值在5种模型中最小,土壤Cd元素实测值与RF模型的预测值拟合效果最佳.同时,基于RF模型的研究区土壤Cd含量空间分布预测结果与实测样点插值结果具有较好的一致性.③在土壤Cd元素健康风险预测中,RF模型对成人与儿童的反演精度均优于其他4种模型,预测结果较好;LR模型验证集预测值变化幅度大,预测结果较差.综上,RF模型具有较好的泛化能力和抗过拟合能力,为研究区土壤Cd含量预测和健康风险评价的最优模型.

关键词：镉(Cd) 含量预测健康风险评价机器学习特征优选

基于安全、市场、民生视角的我国自然资源经济形势分析

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中国矿业 2024年第7期33卷 9-15页

作者：吴初国王楠苏宇李政吴琪高宇张必欣仇巍巍自然资源部信息中心北京100036

自然资源经济形势分析是国家宏观经济形势分析的重要支撑。组成“山水林田湖草沙生命共同体”的各门类自然资源之间的复杂联系必然要求自然资源经济形势分析要坚持系统性。在全面推进人与自然和谐共生的现代化进程中,自然资源最主要的... 详细信息

自然资源经济形势分析是国家宏观经济形势分析的重要支撑。组成“山水林田湖草沙生命共同体”的各门类自然资源之间的复杂联系必然要求自然资源经济形势分析要坚持系统性。在全面推进人与自然和谐共生的现代化进程中,自然资源最主要的工作就是为经济安全筑基础,为市场繁荣添活力,为民生大众谋福祉。基于安全、市场、民生三个视角,研究自然资源在供应风险、市场配置和应急保障之间的关系,选取能够及时更新并反映自然资源状况的基础指标及复合指标,构建自然资源经济形势分析指标体系。通过长期趋势分析结合短期形势研判,对2024年上半年自然资源经济形势进行了分析。通过分析可知,当前我国耕地保护形势态势较好,但耕地质量不高,格局分布不合理;矿产品生产较为平稳,重要矿产品对外依存度较高;房地产市场态势下行,民生保障存在结构性矛盾;地质灾害整体偏重,防灾减灾形势严峻等。为此,提出进一步优化耕地质量和分布格局、推动重要矿产增储上产、优化住宅用地供应结构、提升预报预警服务能力等对策建议。

关键词：自然资源经济形势指标体系安全市场民生