Measurement of coupled hydro-mechanical processes in Rock Fractures in Deep Bedrock

Understanding the coupled hydro-mechanical processes in fractures in deep bedrock is of key importance for many important applications, such as Enhanced Geothermal Systems (EGS), unconventional hydrocarbon exploration and mining. In many applications the fluid-injection related induced seismicity is of particular concern.  To address the HM coupled processes in deep fractures, we bring together two major infrastructures and capabilities, namely the ICDP drilled 2,5 km deep scientific investigation borehole COSC-1 in Åre,  whose hydro-mechanical and chemical properties we have carefully investigated and the SIMFIP (Step-Rate Injection Method for Fracture In-Situ Properties) hydro-mechanical measuring method developed at Lawrence Berkeley National Laboratory, USA that allows determining discontinuities hydraulic and mechanical properties and their in situ variations using coupled pressure/deformation measurements in boreholes.

An extensive field campaign was carried out in COSC-1 borehole, Åre, in June 2019. Cutting edge measurements were carried out at depths previously not measured with this technique at carefully selected fractures and the HM response and rock deformation were determined, along with monitoring of the seismic response. The results will be analyzed and modelled with state-of-the-art modeling in order to obtain an improved understanding of the coupled HM processes in deep hydraulically transmissive fractures and related processes such as induced seismicity. The work is done as a collaboration between Uppsala University and Lawrence Berkeley National Laboratory (LBNL), USA, financed by SGU and USDOE, with participants even from Stockholm University and Lund University. 



Senast uppdaterad: 2021-03-26