Thermo-mechanical behavior of a granodiorite from the Liquiñe fractured geothermal system (39°S) in the Southern Volcanic Zone of the Andes

[Display omitted] •Calculate the dynamic and static parameters from uniaxial and triaxial test after different heat treatments ( 150 °C and through the development of sub-critical cracking at constant temperatures between 50–75 °C. Slowest deformed samples also exhibited lower strengths, attributed to the development of sub-critical cracking. The cyclic triaxial loading test indicated that significant mechanical fracture damage was only initiated above 80% of the peak stress regardless of the number of repeated loading cycles at lower stresses. Low-temperature treatment appears to be a conditioning factor, but not the dominant factor in controlling the physical properties of reservoir hosting rocks. Our findings indicate that thermal crack damage is likely important for developing microfracture related permeability at depths between around 2–6 km where the temperature is sufficiently high to induce thermal cracking. At shallower depths, such was previously estimated the reservoir of Liquiñe, thermal crack damage is only generated adjacent to fractures that remain open and circulate the hot fluids but sub-critical cracking ove