Cu potentials in the Fore-Sudetic Monocline using 4D modeling data

in: Proc. 33rd Gocad Meeting, Nancy, ASGA

Abstract

This work explains a procedure to predict Cu potentials in the ore-Kupferschiefer using 4D modeling and logistic regression (LR) analysis. The predictor variables in the assessments are established from restored horizons that contain the ore-series. Applying flexural-slip to unfold/unfault the 3D model of the Fore-Sudetic Monocline (FSM), we obtained the dilatation parameter and the depth of the Zechstein base at restored times. We found that the positive dilatation outputs and the Zechstein base depth at Late Cretaceous time represent the main structural features related to the Cu mineralization. The positive dilatation outputs may reflect faulting and damaged areas in the rock mass, and hence, relating the fault-fracture systems that drove the fluid circulation from the basement and hosting the early mineralization stages. The Zechstein base depth at Late Cretaceous express the lithostatic pressure that control the hydraulic fracturing during the up-lifting at this time. In the Cu potential modeling, positive dilatation values and the depth of restored Zechstein correspond to predictor variables, and several Cu grades in binary code as targets. Then, we applied LR analysis, available in the free software R, establishing the separating function between mineralized and and non-mineralized locations. The results show more accurate predictions for high Cu-grades when the positive dilatations are taken into account. Keywords: Prospectivity mapping, structural restoration, R, logistic regression, Kupferschiefer.

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BibTeX Reference

@INPROCEEDINGS{,
    author = { Mejia-Herrera, Pablo and Royer, Jean-Jacques },
     title = { Cu potentials in the Fore-Sudetic Monocline using 4D modeling data },
     month = { "sep" },
 booktitle = { Proc. 33rd Gocad Meeting },
      year = { 2013 },
 publisher = { ASGA },
  location = { Nancy },
  abstract = { This work explains a procedure to predict Cu potentials in the ore-Kupferschiefer using 4D modeling and logistic regression (LR) analysis. The predictor variables in the assessments are established from restored horizons that contain the ore-series. Applying flexural-slip to unfold/unfault the 3D model of the Fore-Sudetic Monocline (FSM), we obtained the dilatation parameter and the depth of the Zechstein base at restored times. We found that the positive dilatation outputs and the Zechstein base depth at Late Cretaceous time represent the main structural features related to the Cu mineralization. The positive dilatation outputs may reflect faulting and damaged areas in the rock mass, and hence, relating the fault-fracture systems that drove the fluid circulation from the basement and hosting the early mineralization stages. The Zechstein base depth at Late Cretaceous express the lithostatic pressure that control the hydraulic fracturing during the up-lifting at this time. In the Cu potential modeling, positive dilatation values and the depth of restored Zechstein correspond to predictor variables, and several Cu grades in binary code as targets. Then, we applied LR analysis, available in the free software R, establishing the separating function between mineralized and and non-mineralized locations. The results show more accurate predictions for high Cu-grades when the positive dilatations are taken into account. Keywords: Prospectivity mapping, structural restoration, R, logistic regression, Kupferschiefer. }
}