ABSTRACT
Three dimensional numerical stress field modeling was performed to describe the primary stress field in the Wellenberg area. The model was calibrated using results from hydrofrac stress measurements and analyses of borehole wall breakouts and induced fracturing, as well as geological-tectonic indicators. The numerical model includes the complex geological-tectonic and topographic structure and describes material behavior using a special elasto-plastic material law with smeared discontinuity system and strain-softening for both the matrix and the discontinuities.
