- Laboratory testing
Standard geomechanical testing of strength, stiffness, compressibility and sonic velocities
- Geomechanical characterization from seismic
Utilize log and seismic data for population of geomechanical properties through rock physics and geomechanical relationships
- Analysis of stress field
Analysis of injection tests data (Minifrac, LOT, XLOT, Step rate tests etc.) and log data for stress field determination
- Reservoir compaction and subsidence analysis
- Wellbore stability and sand prediction analysis
Reservoir compaction and subsidence analysis
NGI perform 2D and 3D geomechanical modelling of reservoir compaction and seafloor subsidence, coupling of field scale model towards 4D seismic interpretation and detailed models for wellbore and fault stability.
We have routines for import of data to our Finite Element Tools (i.e. PLAXIS, Abacus) accounting for detailed geometry and property distribution from seismic horizons and geological model (i.e. RMS or Petrel) along with detailed pore pressures distribution (from reservoir simulator i.e. ECLIPSE simulations).
Example of global 2D analysis of reservoir compaction and subsidence due to depletion
Wellbore stability and sand prediction analysis
NGI provides detailed local-scale analysis for the stability around wells or faults both standalone or based on output (effective stress, strain and pore pressures) from field scale (global) analysis. The local analyses includes effective stress changes resulting from the long term production and pore pressure depletion history of reservoir.
Example of local 2D analysis of wellbore stability and standalone local axisymmetric model for wellbore stability and formation damage.
Examples of output from the analysis are displacements along well trajectory and indentification of critical sections through overburden and faults, and critical reservoir depletion and drawdown for onset of sanding. These are valuable input for detailed planning of well trajectory, and evaluations of casing integrity and completion methods during field development.
Also more specialized analysis can be provided to adress specific challenges arising during production or drilling (i.e. formation damage from drilling).
NGI has equipment for standard and specialized geomechanical tests (triaxial cells, HPHT Setup, shear box and carbon fibre triaxial cell for visualisation of deformation and flow in CT scanner). Fundamental deformation and flow mechanisms can be tested for various stress paths representing loading and flow conditions in the reservoir system or overburden.
All cells are equipped for combined geophysical measurements (axial and radial velocity) which makes this unique for linking geomechanics to geophysics and rock physics. In combination with numerical modelling, we can further explore the fundamental mechanisms on laboratory scale and extend from laboratory scale to field scale.