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Changes in seismic two-way travel time in the overburden can be attributed to pore pressure changes in the underlying reservoir. Since cap rock permeability is very small, these stress changes occur without drainage on short term, which means that, depending on stress path, pore pressure may also...

CO₂ saturations are estimated at Sleipner using a two‐step imaging workflow. The workflow combines seismic tomography (full‐waveform inversion) and rock physics inversion and is applied to a two‐dimensional seismic line located near the injection point at Sleipner. We use baseline data (1994 vintage...

Measurements of dynamic elastic properties of shale exhibit dispersion at seismic frequencies as well as between seismic and ultrasonic frequencies. We point to various possible dispersion mechanisms, including viscoelasticity of bound water in the narrow pores associated with clays and squirt flow...

Static and dynamic behavior of isotropic or anisotropic media, including rocks, are conveniently described with a second-order stiffness matrix using the Voigt notation, which linearly relates stress changes to strains. However, experimental and field observations indicate that the dynamic stiffness...

The sealing efficiency and fault stability of the reservoir's overburden are essential in both CO₂ storage and hydrocarbon production. This elevates the importance of induced stress and pore pressure change prediction in the proximity of the production or injection zones. The low-permeability nature...

Rocks surrounding a depleting oil or gas reservoir, or an inflating CO₂ storage reservoir, are characterized by extremely low permeability in order to provide seals over geological time. It is well established that pore pressure change in a reservoir leads to stress changes around it, however, it is...

Time-lapse (4D) seismic is an essential tool for monitoring the subsurface in and around producing hydrocarbon or CO₂ storage reservoirs. The seismic time-shifts, in the reservoir as well as in the overburden, depend on the stress changes and strains induced by the subsurface depletion or the...

In the North Sea, around 2000 off-shore wells are scheduled to be plugged-and-abandoned over the upcoming decades, requiring new cost-effective solutions. Among those, bismuth alloy plugs are raising a major interest, as they have high sealing abilities and require less material volume than cement...