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A novel fracture-cavity reservoir outcrop geological knowledge base construction method considering parameter collection and processing, mutual transformation of data-knowledge, application and update

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Petroleum science 2024年第4期21卷 2184-2202页

作者： Qi-Qiang Ren Jin-Liang Gao Peng Zhu Meng-Ping Li jian-Wei Feng Qiang Jin San zhang institute of Sedimentary Geology Chengdu University of Technology PetroChina Research institute of Petroleum Exploration and Development School of Energy Chengdu University of Technology School of Resources and Geosciences China University of Mining and Technology School of Geosciences China University of Petroleum (East China) School of Geosciences Yangtze University

This study endeavors to formulate a comprehensive methodology for establishing a Geological knowledge Base(GkB) tailored to fracture-cavity reservoir outcrops within the North Tarim Basin. The acquisition of quantitative geological parameters was accomplished through diverse means such as outcrop observations, thin section studies, unmanned aerial vehicle scanning, and high-resolution cameras. Subsequently, a three-dimensional digital outcrop model was generated, and the parameters were standardized. An assessment of traditional geological knowledge was conducted to delineate the knowledge framework, content, and system of the GkB. The basic parameter knowledge was extracted using multiscale fine characterization techniques, including core statistics, field observations, and microscopic thin section analysis. key mechanism knowledge was identified by integrating trace elements from filling, isotope geochemical tests, and water-rock simulation experiments. Significant representational knowledge was then extracted by employing various methods such as multiple linear regression, neural network technology, and discriminant classification. Subsequently, an analogy study was performed on the karst fracture-cavity system(kFCS) in both outcrop and underground reservoir settings. The results underscored several key findings:(1) utilization of a diverse range of techniques,including outcrop observations, core statistics, unmanned aerial vehicle scanning, high-resolution cameras, thin section analysis, and electron scanning imaging, enabled the acquisition and standardization of data. This facilitated effective management and integration of geological parameter data from multiple sources and scales.(2) The GkB for fracture-cavity reservoir outcrops, encompassing basic parameter knowledge, key mechanism knowledge, and significant representational knowledge, provides robust data support and systematic geological insights for the intricate and in-depth examination of the genetic

关键词： Geological knowledge base karst fracture-cavity system Mutual transformation of data-knowledge knowledge base content and application Tarim basin

Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China

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Pedosphere 2007年第3期17卷 331-342页

作者： Su Yong-Hong FENG Qi ZHu Gao-Feng SI jian-Hua zhang Yan-Wu Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou730000 （China） School of mathematics and statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids （TDS） in the groundwater showed a great variation, with 62.5% of the samples being brackish （TDS ≥ 1 000 mg L^-l）. The groundwater system showed a gradual hydro-chemical zonation composed of Na^＋ -HCO3^-, Na^＋ -Mg^2＋ -SO4 ^2 -Cl^-, and Na^＋ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^＋, k^＋, Cl^-, SO^4 , and Ca^2＋, but other processes, such as mixing, Na^＋ exchange for Ca^2＋ and Mg^2＋, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词： Ejin Sub-Basin groundwater quality Heihe River human impact water resources development

THE TAIL ESTIMATION FOR THE DISTRIBuTION OF THE SuPREMA OF A P-BRIDGE

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Systems science and Mathematical sciences 1992年第3期5卷 274-286页

作者： zhang jian (institute of Systems science,Academia Sinica,Beijing 100080,China)

Let X1,X2,…be a sequence of independent random vectors which take values in IR2 and Xi～*** the projection pursuit （PP） method,we canconstruct PP type kolmogrov-Smirnov statistics:kn=（?） 1/n1/2|sum from i=1 to n(... 详细信息

Let Xub>1ub>,Xub>2ub>,…be a sequence of independent random vectors which take values in IRup>2up> and Xub>iub>～*** the projection pursuit （PP） method,we canconstruct PP type kolmogrov-Smirnov statistics:kub>nub>=（?） 1/nup>1/2up>|sum from i=1 to n(Iub>|ub>aup>rup>Xub>?ub>（?）t|-P（aup>rup>Xub>1ub>（?）t）)|,where Iub>[·]ub> is the indicator function of the set [·] and P is a probability *** limit distribution of kub>nub> is the distribution for the suprema of a P-bridgewhose index is the set of all half spaces in IRup>2up>.Let{Wub>pub>（[0,（?）]）∶（?）∈[0,1]up>2up>} be atwo parameter Brownish *** main result of this paper is（?）for all λ,provided P is the uniform distribution on [0,kub>1ub>]×[0,kub>2ub>],0kub>iub>uniform distribution on [0,1]up>2up>.

关键词： P-Bridge half space projection pursuit

Mapping the Farming-pastoral Ecotones in China

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Journal of Mountain science 2009年第1期6卷 78-87页

作者： zhang jian WEI Jie CHEN Quangon institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Tourism College Chongqing Normal University Chongqing 400047 China School of PastoralAgricultural science and Technology Lanzhou University Lanzhou 730020 China Graduate university of the Chinese Academy of sciences Beijing 100049 China

Conventional farming-pastoral ecotones methods of delineating were not quantitative and could not fully show their spatial distribution. The present paper attempts to develop quantitative methods for mapping farming-pastoral ecotones in China. Nine indicators, related to temperature, precipitation and altitude aspects, were selected to quantify ecological susceptibility of vegetation （crops and forage）. Methods of analytic hierarchy process （AHP） and expert score ranking combined with fuzzy set theory were applied to assign the weight for each indicator and to define the membership functions. The geographic information system （GIS） was used to manage the spatial database and conduct the spatial analysis. According to the spatial calculation of evaluation model integrated with GIS, the ecological susceptibility of vegetation （crops and forage） was mapped. Three different zones, pastoral area, farming-pastoral ecotones and farming area, were classified by spatial cluster analysis and the maximum likelihood classification for the numeric map of vegetation ecological susceptibility by GIS. This map was validated by the economic statistical result based on the ratio of the output value from animal husbandry in total output value of agriculture by the National Bureau of statistics in China, indicating that the mapping of the farming-pastoral ecotones may be accepted.

关键词： AHP Farming-pastoral ecotone Fuzzyset theory GIS

近断层砂化白云岩隧洞突水涌砂演化过程及防突岩盘安全厚度研究

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岩石力学与工程学报 2024年第3期43卷 639-652页

作者：张延杰董家兴周志强周伦顺米健刘登学云南省滇中引水工程有限公司云南昆明650000 昆明理工大学国土资源工程学院云南昆明650093 昆明理工大学电力工程学院云南昆明650500 云南省水利水电勘测设计研究院云南昆明650021 长江科学院水利部岩土力学与工程重点实验室湖北武汉430010

滇中引水工程砂化白云岩隧洞突水涌砂灾害频发,严重制约工程进度并威胁着施工安全。通过施工跟踪、砂化白云岩隧洞突水涌砂案例统计、理论分析等手段,总结富水洞段突水涌砂的成灾条件及灾变特征;基于小扑隧洞典型近断层段的突水涌砂灾... 详细信息

滇中引水工程砂化白云岩隧洞突水涌砂灾害频发,严重制约工程进度并威胁着施工安全。通过施工跟踪、砂化白云岩隧洞突水涌砂案例统计、理论分析等手段,总结富水洞段突水涌砂的成灾条件及灾变特征;基于小扑隧洞典型近断层段的突水涌砂灾害原型,采用FLAC3D模拟突水涌砂过程渗流场、应力场、位移场的演化,确定突水涌砂灾害的防突岩盘安全厚度临界判据,并建立系统、可行的灾害防控体系。研究结果表明:(1)突水涌砂通常发生在断层发育的富水强烈、剧烈砂化洞段;(2)突水涌砂灾变演化过程中,强烈、剧烈砂化白云岩孔隙水压力均存在漏斗效应,剧烈砂化白云岩渗流量变化与强烈砂化白云岩相比存在时滞性,并且剧烈砂化白云岩的渗流量明显比强烈砂化白云岩小;(3)强烈砂化白云岩隧洞开挖至距离断层4 m时,隧洞围岩应力出现突变现象,剧烈砂化白云岩隧洞开挖至距离断层8~9 m时,呈现出明显的拉应力区域;(4)强烈砂化洞段拱顶最大沉降于开挖至距离断层1 m时出现,而剧烈砂化洞段位移场演化无明显规律;(5)确定了富水砂化白云岩隧洞防突岩盘安全厚度临界判据,通过工程实例计算得到的最小安全厚度与实际工程预留接近。结合综合超前地质预报、富水砂化白云岩隧洞突水涌砂演化过程建立的隧洞施工期突水涌砂防控体系,可为富水砂化白云岩地下工程易发频发的突水涌砂灾害防控提供借鉴。

关键词：隧道工程富水砂化白云岩工程原型流固耦合演化过程防突岩盘安全厚度

丹江流域山区地表水-地下水水化学特征及其影响因素

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环境科学 2024年第4期45卷 2107-2117页

作者：张子燕伏永朋王宁涛谭建民刘亚磊中国地质调查局武汉地质调查中心(中南地质科技创新中心) 武汉430205 中国地质大学地质调查研究院武汉430074

丹江流域是南水北调中线工程重要水源涵养区,深入研究丹江流域水化学特征及其影响因素,对区域水资源保护及合理利用具有重要意义.通过对丹江流域水样采集与分析,综合运用描述性统计、Piper三线图、Gibbs图、离子比例系数法及氢氧同位素... 详细信息

丹江流域是南水北调中线工程重要水源涵养区,深入研究丹江流域水化学特征及其影响因素,对区域水资源保护及合理利用具有重要意义.通过对丹江流域水样采集与分析,综合运用描述性统计、Piper三线图、Gibbs图、离子比例系数法及氢氧同位素的方法,分析丹江流域水化学特征及其影响因素.结果表明,丹江流域水体整体呈弱碱性,主要水化学类型为HCO_(3)-Ca型,中游离子质量浓度及水化学类型变化频繁.流域水体均受大气降水补给,地表水受蒸发作用影响明显,水化学组分受岩石风化溶解、离子交换和人类活动共同影响. Ca^(2+)和Mg^(2+)源于方解石、白云石及石膏等碳酸盐和硫酸盐矿物溶解,农业活动是水中硝酸盐的主要来源.地表水与地下水频繁转化和支流汇入影响是丹江干流空间分布特征差异化的主要原因.

关键词：丹江流域水化学特征同位素岩石风化离子交换

Capelli identity on multiparameter quantum linear groups

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science China mathematics 2018年第2期61卷 253-268页

作者： Naihuan Jing jian zhang Department of mathematics Shanghai University Department of mathematics North Carolina State University institute of mathematics and statistics University of Sao Paulo

A quantum Capelli identity is given on the multiparameter quantum general linear group based on the(p_(ij),u)-condition. The multiparameter quantum Pfaffian of the(p_(ij), u)-quantum group is also introduced and the transformation under the congruent action is given. Generalization to the multiparameter hyper-Pfaffian and relationship with the quantum minors are also investigated.

关键词： multiparameter quantum groups q-determinants quasi-center Capelli identity q-Pfaffians qhyper-Pfaffians

A cluster-based analysis of propagation characteristics in MIMO relay channels based on wideband measurement

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The Journal of China universities of Posts and Telecommunications 2012年第5期19卷 45-50页

作者： NIE Xin zhang jian-hua TIAN Lei zhang Ping Beijing institute of Spacecraft System Engineering Beijing 100094 China Wireless Technology Innovation institute Beijing University of Posts and Telecommunications Beijing 100876 China

In this paper, the characteristics of clusters induced by a variety of propagation mechanisms in the link from the relay station （RS） to the mobile station （MS） are presented. Based on the results of high resolution channel parameter estimation, an automatic framework integrated with the manual intervention is utilized to perform the cluster identification and tracking. The power proportion and angular spread of clusters are investigated in both the line-of-sight （LOS） and non-line-of-sight （NLOS） scenarios. The measurement results indicate that the channel characteristics of clusters are different from the link from the base station to the MS due to the lower height of the RS antennas.

关键词： relay wideband channel measurement cluster statistics propagation mechanism

Lagrangian statistics in isotropic turbulent flows with deterministic and stochastic forcing schemes

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Acta Mechanica Sinica 2015年第1期31卷 25-31页

作者： Jin-Cai Chen Guo-Dong Jin jian zhang LNM Institute of MechanicsChinese Academy of Sciences

Artificial input of energy into the flow is neces sary to create and maintain a statistically stationary isotropic turbulence for sampling in studying the statistics. Due to the nonlinear coupling among different Fourier modes through the triadic interaction, whether or not various forc ing schemes affect the statistics in turbulence is an impor tant and open question. We present detailed comparison of Lagrangian statistics of fluids particles in forced isotropic turbulent flows in 1283, 2563, and 5123 simulations, with Taylorscale Reynolds numbers in the range of 64-171, us ing a deterministic and a stochastic forcing scheme, respec tively. Several Lagrangian statistics are compared, such as velocity and acceleration autocorrelations, and moments of Lagrangian velocity increments. The differences in the La grangian statistics obtained from the two forcing schemes are shown to be small, indicating that the isotropic forcing schemes used have little effects on the Lagrangian statistics in the isotropic turbulence.

关键词： Isotropic turbulence Deterministic forcingscheme Stochastic forcing scheme Lagrangian statisticalquantities