The discipline of geomechanics is gaining greater recognition in the petroleum industry worldwide. One reason is application of geomechanics is producing significant financial benefits to drilling operations from exploration to field development. Continued success will require delivering actionable information to operational challenges faster, better and at lower cost. Achieving these objectives places significant demands on organizations, technical staff, and software while challenging conventional approaches to solving geomechanics problems associated with over pressure, subsidence, wellbore stability and sand production. Central to creating value through application of geomechanics is a closed loop process that links a mechanical earth model with fit-for-purpose-engineering software, multi-disciplinary teamwork and knowledge management.
This paper describes an integrated geomechanics process and how it benefits operations throughout the field life cycle. Examples illustrate how the process reduces financial risk during drilling and early field development. Benefits of the closed loop approach are contrasted with conventional approaches to the same drilling challenges. Geomechanics will reduce field development risk when reservoir optimization programs incorporate mechanical earth models and establish feedback loops between the model and predicted performance of fracture stimulation and sand management programs.
1. INTRODUCTION
There is a significant financial risk to well construction or field development projects where geomechanics information needed for engineering designs is inaccurate or is absent altogether. Well known examples include the rig cost associated with non-productive time spent combating wellbore instability, lost circulation or well control. Greater expenses are incurred if these issues are not or can not be managed. For example the cost of extra casing strings, tools lost-in-hole, side tracks or loss of the entire well can be attributed to an incomplete geomechanical assessment [1]. Application of a structured geomechanics process has consistently enabled high-technical risk and high-economic risk wells to be drilled and completed below AFE. Knowledge of in-situ stress and rock mechanical properties coupled with engineering software and a mechanism for delivering information to operations are required to design and safely drill a stable borehole with minimum risk.
Risk is defined as the exposure to chance of injury or loss. Here we focus on reducing unexpected financial loss associated with field operations that are based on uncertain geomechanics data. The reduction of financial risk is directly proportional to the quality of information available to decision makers. A structured process for delivering geomechanics information helps to mitigate risk by delivering actionable information in a relevant time frame.
Successful implementation of geomechanics in field operations requires a process for building a mechanical earth model and using it to delivertimely information to decision makers. Constructing a mechanical earth model during the well planning phase and revising it in real time has helped deliver complex wells safely below AFE while accelerating learning about the field. Performing these tasks in a timely manner is placing greater demands on organizations, technical staff, and software while challenging conventional approaches to solving such problems.
This paper describes new technology for applying geomechanics to solve oilfield problems. We describe the process used to deliver geomechanics information to field operations.
