IRM, LLC, Moscow, Russia

A. Yu. Degterev, Leading Expert in Geological Modeling, Candidate of Engineering Sciences, anton.degterev@irmodel.ru

Gluboky Engineering, LLC, Saint-Petersburg, Russia

S. V. Kuzmin, CEO, Candidate of Engineering Sciences, Full Member of the Academy of Mining Sciences

The article focuses on the pr oblem connected with data averaging in block geomechanical modeling. The influence exerted by the scale effect, when the size of a block in the problems in the resource and block geomechanical modeling is changed, is described. It is shown that, although similar, the problems have an essential difference connected with the influence of the scale effect on the reliability of values obtained for each blocks. Aimed to avoid shifted estimates in rescaling of the initial values into the model blocks, and to eliminate information losses when distributing properties of rocks inside each block during block geomechanical modeling, it is required to update the applied procedure of the initial data rescaling into the model blocks. The possible ways of solving the problem are discussed, and an approach to eliminating adverse effects in the data transfer to the model blocks without any extra unwanted harm is proposed. The approach needs no cardinal change in the general modeling procedure and no essential increase in the resource intensiveness of the modeling. The case-study of a real-life deposit shows the influence of data averaging on the model blocks depending on their size, and describes the use of the proposed procedure which enables preserving basic characteristics of the initial data distribution in each model block, which possesses the initial data, and allows prediction of spatial patterns of these characteristics. The proposed approach can be recommended for application in new and existing block geomechanical models.

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