Application of 3D Visual Techniques in Daliuta Coal Mine

Mar.2006J. China Univ, of Mining Tech(English Edition)Vol 16 No. 1Application of 3d Visual Techniques inDaliuta Coal mineZHOU Ye"', LiN Ge, GONG Fa-xiong", LIU Shi-lin", Liu Ya-chuanGuangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, Guangdong 510640, ChinaGraduate School of Chinese Academy of Sciences, Beijing 100039, ChinaChina railway Engineering Consulting Group Co Ltd, Beijing 100020, ChinaAbstract: 3D visualization is one of major problems in"Digital Mine"theory and its technological research fieldThrough the observation of 3D geological models, spatial structural information, connected with the information ofproduction management hidden in geological data, could be detected. In order to meet the requirement of more efficientcoal exploration, a case study of geological characters of the Daliuta Coal Mine is presented in which 3D visual modelsof the ground surface and geologic bodies are established on the basis of data models and data structures of 3D geologymodeling. The main conclusions of this study are as follows:(1)Through analysis and organization of spatial discretedata, the drillhole database is designed with the data of the Daliuta mine; the connections amomg drillhole data are realized and displayed in a 3D environment. (2)Combining real data of the Daliuta mine, drillhole visualization is realizedin a 3D environment by using the CoalMiner systemhe ground surface modeling of the Daliuta coal mine adopteda surface-data model and a tin data structure. (4)3D models of coal seams and rock formations of the Daliuta mine areestablished, which provide a method for the simulation of complex surfaces of geologic bodies. In the end, the modelare applied to the Daliuta coal mine and the result shows that better geological effects are obtainedKey words: 3D visualization, 3D geology modelling, TIN, Daliuta coal mine, CoalMinerCLC number: TP 302Introductionoccur almost day-by-day, and bring about great economic loss and seriously threatens the safety of ourlmResearch and realization of 3Various kinds of geological information, espe- techniques of geologic bodies and phenomena permitcially those complicated geological structures andthe expression of mine conformations and variousphenomena distributed in 3D space can be expressed other kinds of property information and allow vastquantitatively and described clearly in a real 3D en- amounts of data to be managed by diagrams andvironment. Coal deposits are 3D geological entitiesmodern technology. As a consequence, the cost ofwhose locations and corresponding parameters needmanpower and material resources is reducedto be confirmexploration. MajIn this paper we use CoalMiner software to carrydrawings, technological data in mine development out 3D visualization practices in the Daliuta Coaland every process of mine development are conMine of the Shendong Company. For the benefit ofnected with 3D spaceAt present, research on 3D geological models isthe coal mining industry we attempt to provide agood example of 3D visualization. CoalMiner is avery comprehensive both at home and abroad, inoftware package for mine information managementcluding data models, visualization treatments and 3D which has the characteristics of real 3D. It is based ontopological relations (2-1. Many scientists app/y 3Ddata modeling, but little thought is given to visualizaMicroMine software and developed to accommodatetion treatments/ 8-31. Investigations by geologists inreal conditions of mines in China. This software canour country show that the nature of 3D visual soft- simulate the geology and exploring conditions ofware will affect practical applications.The level of information in our coal industrylogical modeling based on data from geology, surveying and mine engineering. One of the authors ofinadequate, so the production efficiency is lower than this paper takes part in the Coding of the software andthat in advanced coal countriesof the world [4] Sedeals with the 3D visualization part of the daliutavere geological disasters caused by coal exploitation ProjectReceived 15 May 2005; accepted 10 July 2005H中国煤化工CNMHGorrespondingauthorTel:+86-13710142885,+86-20-85290763;E-mailaddressyaning307@163.comJ.China Univof Mining& Tech(English Edition)Vol 16 No. 12 Geological Settings of research areaRenderingf 3D model2.1 Mine locationmodel in 3Dof stratumethologyThe Daliuta Coal mine is located in shenmusystem incounty, Shanxi province. It is an oversized, modernRenderingechnologyoal mine belonging to the Shenhua Corporation(theof 3D modelD model ofc bodiesof coal bedmine and road locations are shown in Fig. 1).Theentire area of the daliuta mine is 189. 80 km and coalreserves are 2 318 million tons, of which 1 527 miltechnologyof 3D modellion tons can be mined. The geological structures inbodies modelthe mine are simple, with flat obliquity in the coalbeds. It has the advantages of shallow embedding andFig 2 Flow chart of modelingeasy exploitation. The mine is largely covered withincompact sedimentary material from the QuaterThe major technologies of 3D models of geonary, with bedrock outcrops in part of the area. The logic bodies (including coalrock formationcoal seam is situated in the Yan'an formation. Thefaults, etc)in mines are as followsaverage thickness of the overburden is 195.24 m after1)3D spatial database, formed from the geomet-more recent washing and denudation 5ric characteristics of geologic bodies, geological investigations and drilling-logs. The appropriate data3D spatial databasesNeimenggu2)The optimized method of interactive-SliceDongshengoutlines, a method to regenerate images, is used toDaliutasimulate the surfaces of geologic bodies. It makes useoftlines of geologic bodysurfaces on neighboring geological exploration pro-geological middle planes, to achieveoutlines. which ultimatelyresult in the rendering of geologic body surfacesTaiyuan cityFrom investigations in earlier literature, the"methodprovinceof interactive-slice outline was proposed, but it israrely used in coal fields to simulate geologic bodiessurfacpecially not in the ways of 3D ore bodyYan anmodeling of coal beds, rock formations and faultsLinfen city1104 Steps of 3D Visualization in DrillholesFig. 1 Map showing the traffic pattern of Daliuta coal mineThe structure of drillhole data is one of theimportant and basic data structures in the 3d visual2.2 Areal geological structuremodeling system, which is often used to express andThe Daliuta mine is located at the Shanbei ramps, store various kinds of engineering information com-at the east limb of the Ordos syncline of the North ing from underground drilling, mine explorationChina platform. The coal seam is a low-pitched so on. In a 3D visual system, the 3D spatial databamonocline, in a generally westward direction, with is often used to manage drillhole dataabout a 10 dip angle and 0.5 %1.7% slope. ThereDrillhole data consists of descriptions of the spa-are a few faults, which extend less than 16 km in a tial drillhole positions and various sample data. BasiNw-SW or Nww-Sww direction /55-800cally, the related information coming from drillingBecause of simple geological structures, the ap- engineering can be stored in the database of the 3Dplication of 3D visualization in the Daliuta mine can visual system with the format of the drillhole dataverify the feasibility of 3D visual technique in coal structure, which will adopt appropriate variables orproperty values to provide expressions of all kinds ofgeological elementsThe drillhole data structure includes two files3 Technical routethe drillhole dahole sampling中国煤化工nd the drilThe formerThe technical method of 3d visual mineincludes HoleCNMH Gates elevashown in Fig. 2tion, drillhole depth and dip angle. The second fileZHOU Ye et alApplication of 3D Visual Techniques in Daliuta Coal Mineludes HolelD, SamplelD, the beginning and end mountain ridges, valley lines and so orlocations of samples, sample length, sample valuesThere are many papers dealing with 3D dataand sample lithologymodeling and data structures. Owing to space limiDuring the process of visualization, the drill- tations, we refer thengfile are linked first with HoleID, i.e. sample data ofvarious geologic bodies are linked with the locations:Data pretreatmentof drillholes; the association between the location of dOthersdrillholes and drillhole sample data is then established. Secondly, the visualization of the Daliuta:mine drillholes, realized with the CoalMiner systemOuter database establishmentwas developed with the aid of microminetralian software package. We can theIt theOuter data were imported into 3Dmodel sy stem in undergroundrilling data in the CoalMiner and make use of3D scan function expediently and observe thehole conditions of the mine3D spatial analysisInteractive enclose the outline o5 3D Visualization in daliuta mineGeologic body I1 General design for 3D visual methodbetween outlines of nci3D visualization of the surface in the daliutaI 3D Solidmine is based on the surface-data model the dataVolume Surface ModelRendering oftructure makes use of tin. to simulate the surfaceshape in the mine area more realistically, an ortho-graphic map is superposed on DEM to create a clear,Fig 3 Flow chart of 3D modeling of geologic bodiesⅤ isible effect5.2 Realization of 3d visualization on the surfaceGeologic bodies in the Daliuta mine include rockof daliuta coal mineformations, coal beds and faults, surrounded by surfaces, including upper and lower surfaces of rockFrom the drillhole orientation in the explorationformations, fault surface intersections with rock for- period to the panel design and ground requisition inmations, etc. Ore bodies surrounded by surfaces are the construction phase of the mine area, all activitiesfilled with voxels in the interiorrequire realistic simulations of the soil surface. The3D visualization of geologic bodies consists of geology departments of mines often use all kinds ofvolume surface rendering and volume rendering, scale relief maps to show topographic relief and geowhich is a kind of 3D rendering technique based on graphical elements and describe corresponding relathe surface rendering and volume rendering of 3D tionships between ground surface and undergroundgeologic bodies. In this 3D rendering technique, the by a contrast map between top and bottom of the3D data model is an mixed data model composed of a mine. The method has some limitations In the firstwire frame, surface and the model entity. A flow place, it has a narrow spatial expressive force; Secchart of the entire model is shown in Fig. 3ondly, it falls short in its general spatial effect; noneAt present, the method of volume surface ren- of the mine maps, geology or relief maps can reflectdering is mainly used in 3D visual systems. This is the full view of the mine. In the third place, it is inef-because the attribute statistic and spatial analysis in ficient and needs to be drawn again after each ex-underground 3D space can't be well explained in amination of the comparative relationship betweenpresent period. The space of mining engineering, in- ground surface and underground of a certain line sec-luding laneway, face and panel, etc, is enclosed bytion. So the 3D visual model using remote sensingsurfaces. The software makes use of the data structure techniques, modern survey and mapping techniquesand visual techniques has practical advantagesTIN is made up of a series of continuous trianThe dEm and doM produced by aerial surveysular surfaces, whose shape and size can be obtained are the data sources for the simulation of the grounddepending on the position and density ofsurface. Because DOM has a data information systempoints or nodes. Compared with the elevation-matrixfar superior than that of ordinary maps and with themethod, tiN can change density of samples with the characteristics of topographic relief shown by DEM,omplexity of hypsographic varieties and determine the mine surface model will exceed traditional maptheir locations. Therefore Tin can avoid redundant ping methodsIV凵中国煤化工 d in this padata on flat landforms and show elevation characters per is an infrareCNMHGed by digitalaccording to characteristic terrain points such as photogrammetylow theJ.China Univ,of Mining & Tech(English Edition)Vol 16 No. 1visual models of the ground surface)5)3D solid models of coal seams and rock formations are produced after a solid treatment with triangular networks. Fig. 6 shows the model of the Daliuta coal seam obtained by CoalMinerFig 4 3D surface model of Daliuta mineFig 6 3D model of coal seam in Daliuta mine mine6.2 Modeling methodOn every slice, the top and bottom borderlinesbetween stratum interfaces are alternately fixed, according to the interzone border shown by differentcolored projection lines of drillhole tracks. Then inthe slice plane, the top and bottom borderlines be-tween every stratum interface are linked to form oneFig 5 Detail part of 3D surface model of Daliuta mineclose contour. Then the nodes on the contour of thesection limits of strata between neighboring slicesSteps in the 3D visual methodology of the sur-are utilized to construct the outer outlines of triangu-face of the Daliuta mine are as follows: 1)importlar networks in each strata, In the end. solid treat-DEM data and doM data into CoalMiner; 2) use ments with the surfaces of triangular networks arDEM data to resample DEM that could show topog. carried out. The so-called solid treatment makes useraphic relief in CoalMiner; 3)superimpose DOM of of the OpenGL 3D engine to do illumination treatthe mining area on the corresponding DEM of the ment and supply color in order to forma visual effectthe 3D visual model of the ground surface(DEM of rock formations(or coal seams)are obtained odground surface; 4)rectify the visual angle to observe of a"body "concept. In the end, 3D surface models ofground surface DOM of ground surface)in CoalMiner.7 Conclusions And Expectations6 Design of 3d visual method for both3D visual techniques can clearly display geo-Rock formation and coal seamsogical information of coal mine and provide technological guarantees for safe and high-efficient mine6.1 3D visual flowexplorations. Through observation of 3D geological1)In CoalMiner, we can slice according to cer- models, spatial structural information connected withtain principles after the 3D drillhole model is estab- production management, hidden in geological data,ished. So-called slices are projection planes cut at a can be detectedfixed interval in the tangential direction of the drill1)Through analysis and organization of discreteholes in the range of the visual drilling modelspatial data, the drillhole database is designed with2)Drillhole tracks within a certain proscribeed the data from the drillholes of the Daliuta mine; asdistance are projected on these slice planes to form a well, the connections among drillhole data are real-row of projection lines of drill tracks. 3D problems ized and displayed in a 3D environmentare solved with 2D methods which use the section2)Combined with 3D visual demands in themethod for reference.Daliuta mine " different modeling methods to differ3)Contour lines of coal seams and rock forma- ent modeling objects"are used in the analysis of extions will be fixed manually and alternately by com- isting modeling methodsputer in CoalMiner;3)TE中国煤化工 the daliuta4)Triangular networks in a tin pattern are coal mine adorformed by contour lines in a 3D environment in data structureTHCNMHGCoalMiner4)3D models of coal seams and rock formationsZHOU Ye etApplication of 3D Visual Techniques in Daliuta Coal Mineof the Daliuta mine are established, which provide a with the update of data;method for the simulation of complex surfaces of2)Develop 3d dynamic forecasting and analytigeologic bodiescal techniques for small fault confluents, visual techThe modeling makes use of 3D visual tech- niques of 3D multi-resource data, 3D dynamic ana-niques to simulate realistically the geology and min- lytical and forecasting techniques of coal geology etcing situation. The application of these models in the3)Develop dynamic evaluation and prognosesDaliuta mine has achieved its objectivesfoBecause of time and money restrictions, the 3d treatment techniques for modern information systemsvisualization project presented here is only a demon- to improve safety levels in geologystration experiment. In order to improve 3D visualtechniques, research and practice need to be directed Acknowledgementsas follows1)Develop automatic modeling and dynamice thank the management of the Beijing Remote SensingCompany and the crew of the Shendong team for their helpupdate techniques of 3D complex objects in mines inorder to update the geological models automaticallyReferences[1 Zhou Z w. 3D Visual Technique in Underground [Master dissertation]. Beijing: Institute of Rs&Gis, Peking University,2000.(InC1[3] Peng JY. Geological Visual Technique Theory[Ph D dissertation]. Chinese Academy of Sciences, 1999.(In Chinese)2 Gorg S P, Cheng Y. Geological Guarantee System for Safe and High-Efficient Mine Exploration. Beijing: Coal Industry Press2001.(In Chinese)4] LiQ Y, Zhu X D, Cao D Y Data model of 3D Geological model. Coal Geology of China, 2000, 12 (3): 57-61(In Chinese5 Zhu X D Study on the 3D Visual Technique of Geological Model Master dissertation]. Beijing: China University of Mining6 Hu JX, Wu L x, Gao W Z, et al. application study on volume visualization technique of 3D geoscience modeling, Journal ofChina Coal Society, 1999, 24(4): 345-349.(In Chinese[7 Guo D Z, Du P J, Sheng Y H. Digital earth and study of 3 dimensional Gis. ACTA GEODAETICA et CARTOGRAPHICASCA,2000,29(3):250-256.( In Chinese)[8] Tang ZS. Visualization of 3D Data Sets. Beijing: Tsinghua University Press, 1999. (In Chinese[9 Yang D B Drawing of Mine Map and Management System Based on GIS [Master dissertation]. Fuxin: Liaoning TechnicaUniversity, 2001.(In Chinese)[10 LiQY, Lin Z, Li C M. The status and development of 3D Gis study Science of Surveying and Mapping, 2000,5(2):47-51.( In Chinese)[11] Wang S M. Regularities of Coal Accumulation and Assessment of Coal Resources in Ordos Basin. Beijing: Coal IndustryPress, 1996.(In Chinese)2 Victor J D, Alan P Delaunay Tetrahedral Data Modelling for 3-D GIS Applications, GIS/LIS93. 1993, 671-678[13 Li DR, LiQQ. Study on a hybrid data structure in 3D GIs. ACTA GEODAETICA et CARTOGRAPHICA SINICA, 1997, 26(2):128-133.( n chinese)[14 Li QQ, Li D R. Research on the conceptual frame of the integration of 3D spatial data model. ACTA GEODAETICA etCARTOGRAPHICA SINICA, 1998, 27(4): 325-330(In Chinese)[15 Cui W. Study of 3D Modelling Method in Daliuta Coal Mine master dissertation]. Beijing: Tsinghua University, 2003(In Chinese)中国煤化工CNMHG