Abstract
Inversions of InSAR ground deformation in the Delaware Basin have revealed an aseismic slip on semi-optimally oriented normal faults located close to disposal wells. The slip, occurring over 3–5 years, extends approximately 1 km down-dip, over 10 km along strike, and reaches 25 cm. We develop and calibrate 2D and pseudo-3D coupled pore pressure diffusion and rate-state models with velocity-strengthening friction tailored to this unique height-bounded fault geometry. Pressure diffusion is limited to a high-permeability fault damage zone, and the net influx of fluid is adjusted to match the observed slip. A 1–2 MPa pressure increase initiates slip, with ∼5 MPa additional pressure increase required to produce ∼20 cm slip. Most slip occurs at approximately constant friction. Fault zone permeability must exceed ∼10−13 m2 to match the along-strike extent of slip. Models of the type developed here can be used to operationally manage injection-induced aseismic slip.
Original language | English |
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Article number | e2021GL097330 |
Journal | Geophysical Research Letters |
Volume | 49 |
Issue number | 11 |
DOIs | |
State | Published - 16 Jun 2022 |
Externally published | Yes |
Keywords
- Delaware Mountain group
- aseismic slip
- ground surface deformation
- rate-state friction model
- velocity-strengthening friction
ASJC Scopus subject areas
- Geophysics
- General Earth and Planetary Sciences