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Science China Earth Sciences 2008年第7期51卷 947-954页

作者： B.E.HOBBS A.ORD csiro Division of exploration and mining P. O. Box 1130 Bentley WA 6102 Australia

This paper presents a research methodology associated with approximately a decade old computa- tional geosciences. To demonstrate how it can be used to investigate the dynamic mechanisms of geological phenomenon, we use as an example the equal-distant distribution of gold deposits in a three-dimensional permeable fault within the Yilgarn Craton, Western Australia. The related numerical results demonstrate that: (1) convective pore-fluid flow in fluid-saturated porous media is the control- ling dynamic mechanism leading to the equal-distant distribution of gold deposits along the fault; (2) the main characteristic of the new methodology is to change the traditionally used empirical, descrip- tive and qualitative methodology into the fundamentally scientific principles based predictive and quantitative methodology. Thus, this new methodology provides a modern scientific research tool for investigating the dynamic mechanisms associated with observed geological phenomena in nature.

关键词： computational geosciences research methodology geological phenomena dynamic mechanisms

Effective loading algorithm associated with explicit dynamic relaxation method for simulating static problems

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Journal of Central South University 2009年第1期16卷 125-130页

作者：赵崇斌彭省临刘亮明 HOBBS B E ORD A Computational Geosciences Research Centre Central South University csiro Division of exploration and mining P. O. Box 1130

Based on the fact that a static problem has an equivalent wave speed of infinity and a dynamic problem has a wave speed of finite value, an effective loading algorithm associated with the explicit dynamic relaxation method was presented to produce meaningful numerical solutions for static problems. The central part of the explicit dynamic relaxation method is to turn a time-independent static problem into an artificial time-dependent dynamic problem. The related numerical testing results demonstrate that: (1) the proposed effective loading algorithm is capable of enabling an applied load in a static problem to be propagated throughout the whole system within a given loading increment, so that the time-independent solution of the static problem can be obtained; (2) the proposed effective loading algorithm can be straightforwardly applied to the particle simulation method for solving a wide range of static problems.

关键词： numerical simulation static systems dynamic relaxation loading algorithm

potential mechanisms of pore-fluid movement from continental lithospheric mantle into upper continental crust

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Journal of Central South University of Technology 2008年第1期15卷 81-88页

作者：赵崇斌彭省临刘亮明 B. E. HOBBS A. ORD Computational Geosciences Research Centre Central South University csiro Division of exploration and mining P. O. Box 1130 Bentley WA 6102 Australia

Through integrating the state of the art scientific knowledge in different research fields, some potential mechanisms of large-scale movements of underground pore-fluids such as H2O and CO2 in the continental lithosphere were presented and discussed. The results show that the generation and propagation of porosity waves are important mechanisms to transport mass and heat fluxes from the continental lithospheric mantle into the lower continental crust; the generation and propagation of porosity waves, pore-fluid flow focusing through lower and middle crustal faults, advection of pore-fluids through the lower and middle crust, and whole-crust convection in some particular cases are important mechanisms to transport mass and heat fluxes from the lower into the upper continental crust; heat and mass transport through convective pore-fluid flow is the most effective mechanism of ore body formation and mineralization in hydrothermal systems; due to heat and mass exchange at the interface between the earth surface, hydrosphere and atmosphere, it is very important to consider the hydro-geological effect of the deep earth pore-fluids such as H2O and CO2 on the global warming and climate change in future investigations.

关键词： underground pore-fluid porosity wave continental crust heat and mass transport

Computational simulation of wave propagation problems in infinite domains

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Science China(Physics,Mechanics & Astronomy) 2010年第8期53卷 1397-1407页

作者： ZHAO ChongBin Computational Geosciences Research Centre Central South UniversityChangsha 410083China csiro Division of exploration and mining P.O.Box 1130BentleyWA 6102Australia

This paper deals with the computational simulation of both scalar wave and vector wave propagation problems in infinite domains. Due to its advantages in simulating complicated geometry and complex material properties, the finite element method is used to simulate the near field of a wave propagation problem involving an infinite domain. To avoid wave reflection and refraction at the common boundary between the near field and the far field of an infinite domain, we have to use some special treatments to this boundary. For a wave radiation problem, a wave absorbing boundary can be applied to the common boundary between the near field and the far field of an infinite domain, while for a wave scattering problem, the dynamic infinite element can be used to propagate the incident wave from the near field to the far field of the infinite domain. For the sake of illustrating how these two different approaches are used to simulate the effect of the far field, a mathematical expression for a wave absorbing boundary of high-order accuracy is derived from a two-dimensional scalar wave radiation problem in an infinite domain, while the detailed mathematical formulation of the dynamic infinite element is derived from a two-dimensional vector wave scattering problem in an infinite domain. Finally, the coupled method of finite elements and dynamic infinite elements is used to investigate the effects of topographical conditions on the free field motion along the surface of a canyon.

关键词： wave absorbing boundary dynamic infinite element wave propagation infinite domain computational simulation

Numerical modelling of structural controls on fluid flow and mineralization

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Geoscience Frontiers 2011年第3期2卷 449-461页

作者： J.Robinson P.M.Schaubs csiro Earth Sciences and Resource Engineering PO Box 1130BentleyWA 6102Australia

This paper presents the results of a set of numerical models focussing on structural controls on hydrothermal mineralization. We first give an overview of natural phenomena of structurally-controlled ore formation and the background theory and mechanisms for such controls. We then provide the results of a group of simple 2D numerical models validated through comparison with Cu-vein structure observed near the Shilu Copper deposit （Yangchun, Guangdong Province, China） and finally a case study of 3D numerical modelling applied to the Hodgkinson Province in North Queensland （Australia）. Two modelling approaches, discrete deformation modelling and continuum coupled deformation and fluid flow modelling, are involved. The 2D model-derived patterns are remarkably consistent with the Cu-vein structure from the Shilu Copper deposit, and show that both modelling approaches can realistically simulate the mechanical behaviours of shear and dilatant fractures. The continuum coupled deformation and fluid flow model indicates that pattern of the Cu- veins near the Shilu deposit is the result of shear strain localization, development of dilation and fluid focussing into the dilatant fracture segments. The 3D case-study models （with deformation and fluid flow coupling） on the Hodgkinson Province generated a number of potential gold mineralization

关键词： Structural control Dilation Fluid flow Mineralization Numerical modelling Shilu Cu-deposit Hodgkinson Province

An element by element spectral element method for elastic wave modeling

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Progress in Natural Science:Materials International 2006年第1期16卷 21-29页

作者： LIN Weijun1, WANG Xiuming1,2 and ZHANG Hailan 1(1.Institute of Acoustics, Chinese Academy of Sciences, Beijing 100080, China 2. csiro petroleum, ARRC, po box 1130, Technology Park, Bentley, WA 6102, Australia) Institute of Acoustics Chinese Academy of Sciences Beijing 100080 China csiro petroleum ARRC PO BOX 1130 Technology Park Bentley WA 6102 Australia

The spectral element method which combines the advantages of spectral method with those of finite element method, provides an efficient tool in simulating elastic wave equation in complex medium. Based on weak form of elastodynamic equations, mathematical formulations for Legendre spectral element method are presented. The wave field on an element is discretized using high-order La-grange interpolation, and integration over the element is accomplished based upon the Gauss-Lobatto-Legendre integration rule. This results in a diagonal mass matrix which leads to a greatly simplified algorithm. In addition, the element by element technique is introduced in our method to reduce the memory sizes and improve the computation efficiency. Finally, some numerical examples are presented to demonstrate the spectral accuracy and the efficiency. Because of combinations of the finite element scheme and spectral algorithms, this method can be used for complex models, including free surface boundaries and strong heterogeneity.

关键词： spectral element Legendre polynomial elastic wave modeling element by element.

Explainable artificial intelligence models for mineral prospectivity mapping

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Science China Earth Sciences 2024年第9期67卷 2864-2875页

作者： Renguang ZUO Qiuming CHENG Ying XU Fanfan YANG Yihui XIONG Ziye WANG Oliver P.KREUZER State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519000China Corporate Geoscience Group(CGSG) PO Box 5128 Rockingham BeachWA 6969Australia Economic Geology Research Centre(EGRU) College of Science and EngineeringJames Cook UniversityTownsvilleQLD 4811Australia

Mineral prospectivity mapping(MPM)is designed to reduce the exploration search space by combining and analyzing geological prospecting big *** geological big data are too large and complex for humans to effectively handle and *** intelligence(AI)algorithms,which are powerful tools for mining nonlinear mineralization patterns in big data obtained from mineral exploration,have demonstrated excellent performance in ***,AI-driven MPM faces several challenges,including difficult interpretability,poor generalizability,and physical *** this study,based on previous studies,we devised a novel workflow that aims to constructing more transparent and explainable artificial intelligence(XAI)models for MPM by embedding domain knowledge throughout the AI-driven MPM,from input data to model design and model *** newly proposed approach provides strong geological and conceptual leads that guide the entire AI-driven MPM model training process,thereby improving model interpretability and ***,the development of XAI models for MPM is capable of embedding prior and expert knowledge throughout the modeling process,presenting a valuable and promising area for future research designed to improve MPM.

关键词： Artificial intelligence Mineral prospectivity mapping Geological prospecting big data Domain knowledge Interpretability

NUMERICAL GEODYNAMIC MODELLING OF COUPLED MECHANO-THERMO-HYDROLOGICAL PROCESSES AND ITS APPLICATION IN PREDICTIVE exploration IN THE FENGHUANGSHAN ORE FIELD, TONGLING

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Geotectonica et Metallogenia 2005年第2期29卷 164-173页

作者： LIU Liangming PENG Shenglin ZHANG Yanhua Departinent of Geology Central South University Changsha HN 410083 China csiro Division of exploration and mining PO Box 1130 Bentley WA 6102 Australia

Mineralisation is the result of the coupled multi-geodynamic processes in the crust. The coupled mechano-thermo-hydrological （MTH） processes are the basic physical processes that govern the location of the hydrothermal mineralization, which can be simulated in the computer by using of the numerical codes, such as FLAC. The numerical modeling results can be used not only to explain the features of existing ore deposits, but also to predict the fhvorable mineralization locations. This paper has summarized the basic equations describing coupled MHT processes in the water-saturated porous rocks, the principles of FLAC, and its application to the MHT processes related to copper mineralization in the Fenghuangshan ore field. We used the FLAC to simulate the syn-deformation cooling and fluid flowing evolution after the intrusion was emplaced and solidified. The modeling results suggest a most prospective exploration area where the subsequent exploration supported the prediction and the test bore hole disclosed the high quality copper ore bodies in the target, demonstrating a positive role of the numerical MTH modeling in facilitating predictive ore discovery.

关键词： mechano-thermo-hydrological coupling, geodynamics numerical modeling, mineral prediction Fenghuangshan

Sequence Stratigraphic Delineation and Correlation of the Dongying Formation in the Nearshore and Adjacent Sea Areas, Bohai Bay Basin

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Journal of China University of Geosciences 2008年第1期19卷 54-64页

作者：朱红涛杜远生 LiuKeyu 颜佳新徐亚军杨萍刘新宇 Faculty of Earth Resources China University of Geosciences Wuhan 430074 China csiro Petroleum Resources PO Box 1130 Bentley WA 6102 Australia Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Based on the analysis of well logs, seismic data, core studies, the Dongying （东营） Formation along the nearshore and adjacent sea areas, Bohai （渤海） Bay basin has been subdivided into three third-order sequences from base to top： namely, sequences SQ1, SQ2 and SQ3. The three sequences have different wireline （SP） log responses, showing triple-section characteristics with SQ1 being characterized by primarily flat baseline with intercalation of relatively low spontaneous potential, SQ2 generally exhibiting weak or moderate amplitude spontaneous potential with finger-shaped peaks, and SQ3 having relatively high spontaneous potential with funnel-shaped log curves. On the basis of the triple-section characteristics, the stratigraphic sequences can be correlated consistently throughout the entire study area. A stratigraphic and sedimentary model for sequences SQ1 to SQ3 of the Dongying Formation in the study area has been proposed. The accommodation space change in the two sides of the asymmetrical basin was examined and the asymmetrical basin has the feature of the asymmetrical accommodation space change. The asymmetrical physiography is a vital factor to influence the accommodation changes in additional to the lake level change, tectonism and sediment supply. This may have important implications to similar basins in other parts of China or elsewhere.

关键词： Bohai Bay basin Dongying Formation sequence stratigraphy consistent correlation asymmetrical basin.

A Mathematical Calculation Model Using Biomarkers to Quantitatively Determine the Relative Source Proportion of Mixed Oils

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Acta Geologica Sinica(English Edition) 2007年第5期81卷 817-826页

作者： CHEN Jianping DENG Chunping SONG Fuqing ZHANG Dajiang Research Institute of Petroleum exploration and Development PetroChina PO Box 910 Beijing 100083 Key Laboratory of Petroleum Geochemistry of CNPC PO Box 910 Beijing 100083

It is difficult to identify the source（s） of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model, as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three end- members. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods.

关键词： mixed oil biomarker oil source correlation quantitative determination mathematical model