Description

Designed for you, if you are...

• A well engineer who wants to understand how mud weight recommendations are made and how well trajectory planning can reduce borehole stability problems as well as the likelihood of mechanical well failure in depleting reservoirs due to compaction and faults slip

How we build your confidence

• Examples and case studies from different geological settings
• Exercises to develop some hands-on skills
• Quizzes to test knowledge transfer
• Discussions (Q&A) to help deployment of the learnings

The benefits from attending

• Participants will understand the concepts of stress & strain, tensile & shear failure, and linear elasticity and how that applies to wellbore conditions, covering the risks of borehole instability, fracturing, losses, and mechanical well failure, both under virgin, depleted and re-pressurised reservoir conditions.
• Participants will be able to identify field data to constrain the in-situ stress condition and formations properties, understand the difference between field integrity test and (extended) leak-off tests, construct and interpret pressure-depth plots and Mohr’s circles, and understand the impact of mud weight and well orientation on borehole (in)stability.
• Furthermore, participants will understand how appropriate well trajectory planning can reduce the risk of well failure (unable to produce of re-enter) due to reservoir depletion and re-pressurisation (e.g., due to waterflooding or CO2 storage).

Topics

• Introduction
• Geomechanical project risks
• Workflow, stress in the earth, initial stress
• Vertical principal stress
• Pore pressure basic concepts
• Over-pressure & mechanisms
• Pressure in salt
• Measuring & monitoring
• Minimum & intermediate principal stress
• Pressure-depth plot

• (Principal) stress, Mohr’s circle
• Linear elasticity, Young’s modulus & Passion’s ratio
• Strain, irrecoverable deformations, non-linear behaviour
• Tensile & shear failure, cohesion & friction angle
• Rock mechanical experiments
• Uniaxial deformation, Uni-axial compressibility

• Stuck-pipe mechanisms & prevention
• Stress distribution around the bore hole
• The role of mud weight, examples
• Polar plots: impact of dip angle and azimuth
• Bore hole failure: instability, lost circulation
• Oil-based vs. water-based muds
• Over-pressure & in-fill drilling
• BHS workflow, recommended mud weight

• Field scale geomechanics introduction
• Formation properties from logs
• Offset & other well data
• Modelling, non-linear & failure behaviour
• Reservoir depletion, change of in-situ stress
• Well trajectory planning, in-fill drilling
• Thermal aspects, thermo-elasticity
• Reservoir pressure reflation

• Reservoir compaction & subsidence
• Poro-elasticity & experiments
• Well failure due to reservoir compaction
• Well failure due to slip layers
• Stress on a fault plane, fault reactivation & a-seismic slip
• Reservoir offset: when not to use a Mohr-circle analysis and 3D models
• How to screen for geomechanical risks
• Developing the work plan