Research On Construction Method Of Block Model For Complicated Ore Body Based On The Octree

3D Geological Modeling is the key issue to achieve "Digital Mine" plan, which must be studied and resolved. After nearly30years’ development,3D geological modeling techniques have became more and more perfect, whatever in Theory or application. The tarsk of3D geological modeling is the reconstruction of various types of geological structure of the distribution, which can well describe the internal space of the geological body, and simulate the trends of the various resources in the development process, thus achieving the three-dimensional visual expression of both geological body external structure and internal components. However, due to the difficult of data obtaining, the complex of geological spatial relationships, and the limited capacity of space analysis, the three-dimensional modeling faces many technical challenges when deal with complex geological bodies.The main study content of this thesis is about the modeling of complex ore bodies, and it focuses on the key technologies of the octree block model in massive data management to speed up the speed of model building and improve the express accuracy about the shape of the complex ore body. In this paper, we have make a in-depth research about the construction method based on octree structure of the complex ore body block model conducted, the main research contents and results are as follows:(1) Based on a comparative analysis of three-dimensional data model, summing up the conclusion that octree structure is an important data structure for building a complex ore body block model. Octree structure has the advantages of high efficiency of compression, simple structure, flexible operation, so it is more suitable to express ore body object, because ore body object often has complex structure and uneven internal properties.(2) Traditional octree block model construction method is well studied and a conclution is got that traditional methods don’t do well in redundant data, speed and accuracy of the model, which may be well improved in this research.(3) An in-depth study is made in linear octree encoding, and a new method to build a linear octree node location codes is proposed on the basis of the traditional coding methods. That is, by calculating the location code of the octree nodes in its elders node, ranging these location code in descending order seniority. By the use of this method, order only related to the depth of the node, which effectively avoid the deficiencies of the traditional linear octree in encoding, and improve the speed of encoding.(4) Making a detailed summary of the build process based on the octree structure of the complex ore body block model, and developed the key algorithms involved to build a complex ore body block model, including the effective management of the block model algorithm, block andwhether the intersection of the surface models of complex ore body detection algorithm, as well as point in the inside and outside of the complex ore body surface model to determine the algorithm.(5) Becaus octree structure has the characteristic of irregular and complex ore body block model of the mass of the data, the Z curve the management octree block model of the concept, design and the irregular space based on the octree structure Zcurve fill algorithm.(6) A in-depth research on the intersect on the surface model of the octree nodes and complex ore body detection algorithm is made, and an accurate judgment whether the intersection of the octree nodes and complex ore body is put forward, namely, by calculating the octree tree node with the OBB tree surrounded by the intersection of the surface of the ore body in the box model facet number and the distribution of precise intersection detection. Designed and implemented the algorithm to calculate the intersection point of the octree nodes and complex ore body surface model of triangular patches.(7) Based on the algorithm of the BSP tree method that determines whether a point is in a complex ore body surface, a more in-depth study is made.In short, the innovation and research significance in this paper can be summed as:(1) A new octree node location codes is roposed, which improves the speed of the linear octree encoding.(2) A massive data management method is developed, which effectively achieved the manage and retrieve in the irregular space Z curves of program.(3) Achieved the efficient conversion between a surface model and a complex ore body block model.Finally, an applicational example is given, which well test the validation of the theory and algorithm.