Publikasjoner og ansvarsområder
Application of a Bingham viscoplastic model to borehole closure: comparison between two numerical approaches
Several field observations by cement bond logs (a technique used to detect substance behind casing) indicate progressive borehole closure in soft rock such as shale. This study considers the problem of progressive borehole closure in an elasto-viscoplastic rock mass. The behavior of the rock mass is...
Time-dependent closure of a borehole in a viscoplastic rock
Relations between Static and Dynamic Moduli of Sedimentary Rocks
Static moduli of rocks are usually different from the corresponding dynamic moduli. The ratio between them is generally complex and depends on several conditions, including stress state and stress history. Different drainage conditions, dispersion - often associated with pore fluid effects – heterog...
Plug & abandonment of offshore wells: Ensuring long-term well integrity and cost-efficiency
There is an upcoming "P&A wave" of wells that need to be permanently plugged and abandoned, especially in mature, offshore areas such as the North Sea and Gulf of Mexico. It is important to ensure that plugged wells do not leak after abandonment, as there could be several potential lea...
SHALE AS A SEALING BARRIER AROUND DEEP WELLS
The build-up of contact pressure behind casing due to formation creep
Laboratory test for studies on shale barrier formation
Shale Rock Physics
Shale rock physics may be used for improved monitoring of subsurface changes in and around a depleting reservoir. It is shown how rock physics plays a key role in interpreting time-lapse (4D) seismic into geomechanical attributes as changed stresses, strains and pore pressure. This knowledge is of i...
Skempton's A – A key to man-induced subsurface pore pressure changes
Fluid production from or injection into a subsurface reservoir leads to stress pressure changes inside and outside the reservoir. The overburden often consists of low permeability shale, and the undrained pore pressure response may be estimated from Skempton’s empirical equations. The key parameters...