Research on dynamic reserve calculation technology of metal deposits based on three-dimensional geological model

  As we all know, mineral resources are non-renewable resources, and with the gradual increase of mineral resources development, the global mineral resources are showing the trend of sharp decrease.

Therefore, the conservation of mineral resources has become a global consensus. In the process of development of relevant geographic information technology and improvement of relevant geographic information system concept, the geological and mineral exploration technology has been greatly improved, which has a positive impact on promoting the realization of automated management of geological and mineral resources.

In the rapid development of geographic information technology, three-dimensional geological modeling technology has been gradually derived, and how to reasonably apply this technology to the calculation of solid mineral reserves is the focus of China’s research on the calculation of mineral reserves. The following paper will mainly focus on the dynamic reserve calculation technology of metal deposits based on three-dimensional geological model for in-depth investigation.

  1, the general process of dynamic reserve calculation

  In the process of exploration and mining of geological minerals, serious mineral reserve depletion problems will arise, and no matter what factors cause mineral depletion, it is necessary to reasonably calculate the amount of depletion based on the initial reserves, in the completion of an exploration, it is necessary to reasonably re-model the ore body, the newly shaped model and the calculated reserve value as the basis of subsequent exploration.

After reconstructing the initial reserves, the reserves of the ore body may deviate from the initial reserves to a certain extent, which illustrates the dynamic nature of the ore body reserves. Generally speaking, the dynamic change process of ore body reserves can be divided into three stages: the first stage is the initial reserve calculation, the second stage is the structural or internal structural change of the ore body, and the third stage is the new reserve value resulting from the change of the ore body.

  Among them, the first stage needs to be fully executed based on the various exploration data collected and the reserves calculated. The second stage is a dynamic change in volume, where the volume of the ore body decreases due to the change in mineral reserves, and increases due to the new tip extinction point. The third stage occurs after the ore body shows a variety of changes, the reserves within the mineral re-stacking and superposition, making new changes in reserve values.

  2. Calculation of initial reserves

  After dissecting the surface of the ore body, a number of different cubic elements will be derived, and these cubic elements can be calculated based on the existing samples for the taste interpolation, generally speaking, in the process of calculating the initial reserves, the method that can be used is mainly the weighted average method. This method is mainly for the middle of the unit block has a certain influence on the surrounding sample taste reasonable weighted average calculation, and finally to obtain the corresponding taste value. The specific values obtained are cubic elements, and these cubic elements are added together to obtain the specific values of the initial reserves.

  3、Dynamic update of ore body model with local spatial Boolean operation of mining area and ore body

  3.1 Algorithm flow

  First of all, a mining area surface model is constructed, and after this model is constructed, the spatial Boolean cut calculation with the antibody model is launched, and the new ore body and sub-blocks are calculated. Finally, we can calculate the reserves based on the volume of the sub-blocks themselves, and add up the volume of the volume to obtain the specific mining volume value.

  3.2 3D solid model space Boolean operations

  Boolean is a British mathematician who invented the logical-mathematical calculation method for dealing with the relationship between binary values. This logical algorithm is invoked in graphical operations to combine simple basic shapes to produce new forms. Spatial Boolean operations are performed by merging, differencing, and intersecting two or more objects to obtain a new object form.

  3.3 Spatial indexing properties of the ore body model

  When the ore body model is built, it has maximum and minimum values on each of the three axes XYZ, and these six values form a spatial enclosing box. The ore body is composed of several block segments, and each block segment also has a spatial enclosing box. In this way, all cubic elements of the ore body are spatially indexed according to the enclosing boxes of each block segment.

  3.4 Modeling of the mining area surface

  Using the upper and lower boundaries of the mining area as constrained boundaries, a TIN with boundary constraints is constructed for the discrete points of the top and bottom faces to form a triangular face set of the top and bottom faces. Since the upper and lower boundaries of the mining area have the same number of points, it is easy to build the triangular face piece set. Let the boundary have N points, then the upper and lower boundaries can form N spatial quadrilaterals, and each spatial quadrilaterals can be divided into two triangles according to the diagonal, and all these triangles form the edges of the extraction area.

  4、Dynamic update of ore body model based on inserted local reconstruction

  Generally speaking, before mineral development enterprises develop mineral resources, they need to do the corresponding exploration work, through which the exploration work can fully collect and understand the local mineral resources information, and then based on this information can summarize the data resources of the boundary extinction point, through this data resource, it can effectively realize the re-architecture of the ore body, so as to ensure that the ore body and the specific situation The ore body can then be effectively re-architected to ensure that the ore body conforms to the specific situation. In the original orebody model, a new boundary extinction point is inserted, which will have a partial impact on the orebody, but is not serious, while the reconstructed part of the affected orebody needs to be reconstructed, which not only can effectively reduce the corresponding reconstruction calculation, but also can make the calculation efficiency improved. Usually, the affected part of the ore body mainly includes the surface of the ore body and the internal elements of the ore body, and the reconstruction is mostly carried out for these two parts.

  In the mining of minerals, the relevant enterprises need to conduct a comprehensive inspection of the minerals mined to obtain the actual taste or content of the ore body, after obtaining a series of data, based on these data can be better assay processing, which will make the calculation of the actual reserves of the ore body more appropriate to the actual situation. The data obtained are usually interpolated data, which will have a certain influence on the ore body reserves, but the influence is only local, and in the process of calculating the reserves, only the interpolated values of the body elements in the affected area are needed to calculate.

  5. Conclusion

  Through the analysis of this paper, it is clear that in the process of local reconstruction of the ore body, it is necessary to fully consider both internal and external factors of the ore body, to clearly understand the form of the new tip extinction point and the new samples inside the ore body, to carry out the calculation of the body elements for the affected area, and to filter out the actual body elements that need to be calculated, which effectively reduces the calculation volume and makes the calculation speed significantly faster.

Based on the three-dimensional geological model, the calculation of dynamic reserves of metal deposits can be effectively implemented to accurately summarize the precise content of minerals, which has a positive impact on the development of China’s mineral enterprises.