3D Geometrical modeling of folded layers: a case study from
lead and zinc mine of Anjire, Isfahan, Iran
A. R. Fereshtenejad1,*, M. K. Afshari2, A. Laderian3, H. Safaei4, J. J. Song5
1
2
Graduate student, Seoul National University, Seoul, Korea
Graduate student, Islamic Azad University (Bafgh branch), Iran
3
Department of Civil Engineering, Arak University, Iran
4
5
Department of geology, University of Isfahan, Iran
Department of Energy Systems Engineering, Seoul National University, Seoul, Korea
*a.r_fereshtenejad@snu.ac.kr
Abstract
The first step to determine mechanical and hydraulic properties of rock masses is the evaluation of
geometrical characterizations of discontinuities. Discrete Fracture Network (DFN) models are developed
to model the geometrical properties of discontinuities using the values and statistical law distribution of
these properties extracted from the analysis of core logging and outcrops mapping. Among all properties
of discontinuity, shape is one of the most controversial ones. In previous DFN models, discontinuities were
considered as limited or unlimited planes while in some fields, curve-shaped discontinuities are observable.
Based on previously accomplished researches, planar assumption in rocks containing curve-shaped
discontinuities leads to irreparable errors in subsequent analysis. Curve-shaped discontinuities and reasons
of their creation have not yet been specifically classified. However it is obvious that there are reasons that
could create this kind of discontinuities. Folding is the most common factor in the creation of curve-shaped
discontinuities in mines and engineering works. In this paper, a practical 3D geometrical method is
proposed to model folded layers which noticeably reduces previous generated errors. The modeling method
uses Fourier analysis and Spline function to model folded layers and generates suitable results for
mechanical analysis software. Based on the proposed method, a practical MATLAB script named RocFold
was developed. Finally, to evaluate the applicability and the feasibility of the proposed model and script, a
typical folded structure in Anjire lead and zinc mine in Isfahan province, Iran was applied.
Keywords: Geometrical modeling, Curve-shaped discontinuity, Folded-layer, DFN model, Fourier
analysis.