Poroelastic Response Of An Induced Hydraulic Fracture To Water Injection: A Case Study Of The Horstberg Geothermal Reservoir, Germany

The objective of this study is to determine the hydraulic and the corresponding poroelastic response of an induced hydraulic fracture to water injection into the Horstberg geothermal reservoir. The Horstberg geothermal site is based on a mono-borehole concept, i.e. the circulation of cold and warm water occurs only within one single well. This well is completed in a multilayer sandstone reservoir at a depth of approximately 3700 meter. Here, a massive hydraulic fracture has been created by water injection, resulting in a hydraulic connection between the upper and lower reservoir formations (Solling and Detfurth formations within Buntsandstein). The results of 2D benchmark models and a 3D reservoir model illustrate the role of poroelasticity on water injection, fracture deformation, pore pressure and stress redistribution.