Investigation of fault-related small-scale fuid fow in geothermal felds by numerical modeling

In this paper, hydrothermal circulations and temperature distributions in geothermal areas with fault zones are investigated.It is shown that existence of the fault zones infuences both the fuid circulation patterns and velocities. Reciprocal infuence of the localfuid circulations and the temperature distribution is demonstrated. A 2-dimensional square porous layer is used for modeling thegeothermal feld. Faults are modeled as vertical porous layers. It is assumed that faults are located inside the geothermal feld and have ahigher permeability than the feld itself. Anisotropic and isotropic models are used to simulate the permeability structure of the faults.Several parametric studies, such as the diferent numbers, sizes, and locations of the faults within a geothermal feld, are conducted. It isdemonstrated that fuid fow pattern and temperature distribution are strongly linked to these parameters.

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