29 international collaboration in disposal research fs experiment at mont terri birkholzer lbnl
1. Spent Fuel and Waste Science and Technology
International Collaboration in
Disposal Research:
FS Experiment at Mont Terri
Jens Birkholzer
Lawrence Berkeley National Laboratory
SFWST Working Group Meeting
“International Session”
UNLV, Las Vegas, NV
05/24/2017
2. Spent Fuel and
Waste Science and
Technology
Fault Slip Experiment (2015-2016)
Objectives
– Potential for leakage along faults that intersect a sealing formation (e.g.,
triggered by gas pressure buildup, or glacial loading, or nearby earthquakes)
– Risk of induced seismicity
Concept
– Inject water into packed-off intervals in a borehole intersecting a fault
– Stepwise increase fluid pressure Monitor fault permeability, stress and strain
tensors evolution, and induced seismicity
The structure of the Main Fault has
been accessed through gallery
outcrops and fully cored boreholes
4. Spent Fuel and
Waste Science and
Technology
Seismicity Observed During Injection
Injection 2
in the fault
damage zone
Monitoring
across the main
fault interface
Injection
pressure
Monitoring
pressure
Injection
flowrate
m.e.q.
Rupture at the injection source (FOP)
FOP Injection > FOP Monitoring
Interface between fault core and fault
damage zone has weaker properties
Magnitude ~ -2.5
Source radius ~ 1.2m
5. Spent Fuel and
Waste Science and
Technology
Complex Fault Movement
• Alternate slip, no-slip and high-dilatant periods
• ~75% of the movement is aseismic
• Large pressure drop is preceding the earthquake
slip slip
Dilatant
event
slip
6. Spent Fuel and
Waste Science and
Technology
Impact of Fault Slip on Permeability
6
Fault planes reactivated
during the different injection
tests
Injection 1
Injection 2
Injection 3
Injection 4
7. Spent Fuel and
Waste Science and
Technology
Planned Future Work
Fault Permeability Changes Due
to Distant Earthquakes
Long-term Injection and
Permeability Tests
Use Deformation Data to
Estimate Stress Field
