Hydromechanical characterization of a fractured crystalline rock volume during multi-stage hydraulic stimulations at the BedrettoLab


Date

2024-12

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

Multi-stage hydraulic stimulation experiments were conducted at the Bedretto Geothermal Testbed (Switzerland) at a depth of over 1 km to study seismo-hydromechanical processes at the hectometer scale. Eight intervals with a total length of 206 m were stimulated within a densely monitored, fractured granitic rock volume. Geological characterization shows that all intervals contain NE-SW striking, steeply dipping fractures, but the transmissivity and natural inflow vary between intervals. Reactivation pressures estimated from injectivity increases during stimulation indicate shear reactivation rather than hydraulic jacking, suggesting reactivation of pre-existing non-filled fractures. Overall, the seismo-hydromechanical response to stimulation is heterogeneous and indicates channelized flow.

Publication status

published

Editor

Book title

Journal / series

Volume

124

Pages / Article No.

103126

Publisher

Elsevier

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Underground research laboratory (URL); Multi-stage hydraulic stimulation; Enhanced Geothermal System (EGS); Fractured crystalline rock; Hydromechanics; Bedretto Underground Laboratory for Geosciences and Geoenergies

Organisational unit

03953 - Robertsson, Johan / Robertsson, Johan check_circle
03476 - Giardini, Domenico / Giardini, Domenico check_circle
03476 - Giardini, Domenico / Giardini, Domenico check_circle
02818 - Schweiz. Erdbebendienst (SED) / Swiss Seismological Service (SED) check_circle
02334 - BULGG - Bedretto Underground Lab / BULGG - Bedretto Underground Lab

Notes

Funding

182150 - In situ stress variations near faults considering fault zone rock rheology - implications for reservoir stimulation and associated seismicity (SNF)
ETH-06 19-1 - Creating a hierarchy of fracture network in enhanced geothermal systems (EGS) through innovative hydraulic fracturing stimulation (ETHZ)

Related publications and datasets

Is supplemented by: