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The offshore reservoir engineer: A significant benefit to well testing operations

Well testing is both a significant expenditure to oil and gas companies and a vital indicator as to whether the well is financially viable or not. Why then don’t more companies insist on having a reservoir engineer on the rig to provide an on-site management of the process and an immediate interpretation of the test results?

Reservoir engineers are typically involved in the planning phase of the test – before the operations commence – and then in the interpretation of the well test data after the event. But very rarely are they now seen on the rig while testing is underway. Undoubtedly there have been significant improvements in surface read out technology, electronic data acquisition systems and improved data links with onshore. Data can be quickly relayed back to shore, and then on to the office where the reservoir engineer and management can view the information, interpret the data and make decisions on the operation of the test. However, with tests very rarely following the exact plans put in place, there are so many factors that change and fluctuate during the test that a remote view in an office thousands of miles away may not take into account all of the information that an on-site reservoir engineer can see.

OPC reservoir engineers have recently been on offshore rigs to oversee test programs and they suggest the following benefits that their presence brought to the procedures:

Decision-making – Objectives of well tests can develop as the test itself progresses and decisions often need to be made based on analysis of a live data set.

“Ownership” of data offshore. Having a dedicated professional to take responsibility for data collection, transmission and interpretation optimises decision making back in the office and on the rig in real-time.

“Protection” of the data. Prevention of any actions which may unknowingly affect data quality. There is also the benefit of an extra “pair of hands” – particularly important during final build ups.

Responsibility for overseeing sampling. Helping to ensure samples taken are representative of the reservoir.

Communication fail-safe. Should something happen with communication links onshore, the offshore reservoir engineers take responsibility to ensure the test progresses as effectively as possible.

Familiarity with data set. Features of the data can be identified easier due to increased familiarity with the data set and recording of activity which may be missed on well test report “job logs”.

Full conditions. Communication of the full conditions of the test back to onshore management and engineers ensures that no important factors are missed out during interpretation.

Flexibility. “Prescriptive” well test programs can be inflexible if unexpected conditions should arise. There is particular benefit in appraisal/exploration wells where uncertainty is greater.

Well testing can represent a huge proportion of expenditure to companies. This is particularly true of smaller capitalisation public operators, where test results leaked to the markets (intentionally or otherwise) can lead to volatile flows of capital both in and out of the business. Early interpretation and communication of such results to management on-shore can facilitate the proper planning and preparation of releases of information to regulate the flow of capital to and from the business. This can help fund further exploration, appraisal and development.

OPC Managing Director Piers Johnson said “I am a great supporter of having reservoir engineers on the rigs when you are undertaking a well test in uncertain conditions. The ability to take decisions on the spot can really increase the success potential of the well testing program and ensure that any unforeseen problems can be overcome far more easily.”

On-site operational experts
While OPC is well known for the consultancy services we provide from the comfort of an office, a high proportion of the work we undertake is in operational roles on rigs and platforms. We provide expertise through consultants or as a managed project in a wide variety of areas including:

  • Drilling supervision/engineering
  • Well test management/engineering/supervision
  • Completion supervision /engineering
  • Operation and well site geologists