OPC began life as a well testing consultancy in 1987 and whilst growing into a fully integrated subsurface engineering, geosciences and production technology provider, it's no surprise that well testing remains an integral part of the business. OPC are often asked to analyse data from well tests where incorrect methods and been employed to collect the data and generally the test has been rushed and poorly planned. This leads to inconclusive, ambiguous and false reservoir characterization, additional costs, delays and confusion. Ultimately test objectives are not met, resulting in ill-informed business decisions being made regarding further development
Here we would like to provide some detail on some of the most common issues we've observed when an un-integrated approach is taken to testing operations.
Reservoir Engineers interpreting a well test can often be detached from the planning and operations phases with no first-hand knowledge of what occurred during a test. Looking back at a well test report, important details are often missed and the data set may consequently be misinterpreted. In addition to this, operations teams can often be based in a different country to the team planning the well test, resulting in communication issues.
No Clear Objectives
It is essential that all objectives of the well test are well established, clearly communicated and fully understood. A plan as to how the objectives are to be met needs to be fully integrated into the design of the test and discussed beforehand to ensure all stakeholders in the test (particularly operations staff) recognise and understand the reasons behind each action. Due to the uncertainty involved in well testing, the direction of a well test can change as unforeseen or unavoidable factors appear. This can be anything from equipment failure to unexpected reservoir properties. It is important that any forward plan still aims to meet the original objectives and future operations do not cause a conflict, potentially leading to unmet objectives or additional cost. In these situations, due to cost, objectives may be changed or re-prioritised.
For Operators of all sizes, testing is an infrequent and specialist activity and consequently, the operator staff can be less familiar with well testing operations or interpretation. Because of this, only the biggest E&P companies typically retain significant well testing capabilities within their organisation. When it comes to testing, the companies either bring in expertise in the form of contractors or rely on existing and potentially inexperienced staff.