@article{CacaceBloecherWatanabeetal.2013, author = {Cacace, Mauro and Bl{\"o}cher, Guido and Watanabe, Norihiro and M{\"o}ck, Inga and B{\"o}rsing, Nele and Scheck-Wenderoth, Magdalena and Kolditz, Olaf and H{\"u}nges, Ernst}, title = {Modelling of fractured carbonate reservoirs - outline of a novel technique via a case study from the Molasse Basin, southern Bavaria, Germany}, series = {Environmental earth sciences}, volume = {70}, journal = {Environmental earth sciences}, number = {8}, publisher = {Springer}, address = {New York}, issn = {1866-6280}, doi = {10.1007/s12665-013-2402-3}, pages = {3585 -- 3602}, year = {2013}, abstract = {Fluid flow in low-permeable carbonate rocks depends on the density of fractures, their interconnectivity and on the formation of fault damage zones. The present-day stress field influences the aperture hence the transmissivity of fractures whereas paleostress fields are responsible for the formation of faults and fractures. In low-permeable reservoir rocks, fault zones belong to the major targets. Before drilling, an estimate for reservoir productivity of wells drilled into the damage zone of faults is therefore required. Due to limitations in available data, a characterization of such reservoirs usually relies on the use of numerical techniques. The requirements of these mathematical models encompass a full integration of the actual fault geometry, comprising the dimension of the fault damage zone and of the fault core, and the individual population with properties of fault zones in the hanging and foot wall and the host rock. The paper presents both the technical approach to develop such a model and the property definition of heterogeneous fault zones and host rock with respect to the current stress field. The case study describes a deep geothermal reservoir in the western central Molasse Basin in southern Bavaria, Germany. Results from numerical simulations indicate that the well productivity can be enhanced along compressional fault zones if the interconnectivity of fractures is lateral caused by crossing synthetic and antithetic fractures. The model allows a deeper understanding of production tests and reservoir properties of faulted rocks.}, language = {en} } @article{CherubiniCacaceBloecheretal.2013, author = {Cherubini, Yvonne and Cacace, Mauro and Bl{\"o}cher, Guido and Scheck-Wenderoth, Magdalena}, title = {Impact of single inclined faults on the fluid flow and heat transport - results from 3-D finite element simulations}, series = {Environmental earth sciences}, volume = {70}, journal = {Environmental earth sciences}, number = {8}, publisher = {Springer}, address = {New York}, issn = {1866-6280}, doi = {10.1007/s12665-012-2212-z}, pages = {3603 -- 3618}, year = {2013}, abstract = {The impact of inclined faults on the hydrothermal field is assessed by adding simplified structural settings to synthetic models. This study is innovative in carrying out numerical simulations because it integrates the real 3-D nature of flow influenced by a fault in a porous medium, thereby providing a useful tool for complex geothermal modelling. The 3-D simulations for the coupled fluid flow and heat transport processes are based on the finite element method. In the model, one geological layer is dissected by a dipping fault. Sensitivity analyses are conducted to quantify the effects of the fault's transmissivity on the fluid flow and thermal field. Different fault models are compared with a model where no fault is present to evaluate the effect of varying fault transmissivity. The results show that faults have a significant impact on the hydrothermal field. Varying either the fault zone width or the fault permeability will result in relevant differences in the pressure, velocity and temperature field. A linear relationship between fault zone width and fluid velocity is found, indicating that velocities increase with decreasing widths. The faults act as preferential pathways for advective heat transport in case of highly transmissive faults, whereas almost no fluid may be transported through poorly transmissive faults.}, language = {en} }