Assessing Risks of Fault Reactivation through Geomechanical Simulation

Extraction of hydrocarbons always leads to changes in the existing subsurface stresses. Our industry is well aware these changes may result in dangerous safety implications and other undesirable consequences, so we all agree it is imperative to be able to predict subsurface stresses accurately and precisely. In addition, they can affect the integrity of the reservoir and thereby oil and gas production. They need to be properly understood and taken into account for reliable reserve estimates, but also for more optimal development strategies.

Safety, reliability, and profitability are three pillars of the oil and gas industry. Geomechanics is critically relevant and important for these three points.

Some applications of geomechanics:

• Fault stability analysis to understand and avoid any triggered seismicity under production conditions
• Caprock integrity or equipment integrity analysis to prevent costly environmental disasters
• Lost returns and wellbore stability analysis for ensuring reliable and efficient drilling processes
• Water injection and stimulation analysis to optimize oil and gas production
• Water disposal and drill cuttings re-injection analysis for efficient waste management

In this paper, we will focus on the fault stability under production application and relate important considerations when combining geological modelling, reservoir flow and geomechanical simulations.