ACCELERATED BROWNFIELD RE-DEVELOPMENT I: EUROPEAN MAJOR OPERATOR
By Dr Michael Gibson
This first section of the three updated well consultancy articles shows how www.wellideas.co.uk is flexible enough to manage and deliver bespoke well consultancy programs worldwide for a variety of Operators. In this article, www.wellideas.co.uk describes how it managed and delivered a customized / bespoke well brownfield production programme for a major Operator based in the UK with Assets in Norway, Europe, and the UK. A specialised, highly focused team of experts in Production, Reservoir, Seismic, Re-drilling and Well Workover Services comprising a multi-national group of expert personnel with the aim of a) determining how remaining reserves might be accessed using new technology and b) what the capital expenditure was likely to be in utilising this new technology was assembled.
The team took a field-by-field approach, beginning with its understanding of the reservoir (one example, the first figure, shows that the reservoir was comprised of both chalk and sandstone) and then its performance over time in terms of oil production, gas production and water production. An example of a relevant schematic is shown in the second diagram. This allowed personnel to see at what rate water production was rising whilst oil production was falling, and to note the key oil fall-off rates and rise in water production rates, along with any other anomalies. In many cases, oil production had been shut-off some time ago and it therefore had to be investigated whether a full workover might prove beneficial as opposed to any possible intervention.
The options open to the Operator in Terms of Workover were a) Removing the Existing Production Tubing and Re-completing the well; b) Side-tracking existing wells through either slim-hole drilling assemblies or Coiled Tubing; c) Acidizing certain reservoir matrices, d) Fracking certain matrices, e) Water-shut-off, f) Lowering surface back-pressure for example.
With oil and gas currently at such high prices, several Operators are beginning to assess the viability of “Brownfield Re-Development”, literally to see if there are any attractive ways in which remaining reserves can be produced.
Typically, over time, oil production decreases whilst was production increases. The schematic below shows the “production” behaviour of a “classic reservoir”. The key to such a “Brownfield Re-Development Study is to understand the reservoirs and their production performance over time, and to see if there’s any “low hanging fruit” left so that it may be produced economically. This requires specialist teams, and investment, but there have been good results.
This Brownfield Re-Development Project was carried out in Norway, Holland and the UK, with extensive data being made to all delegates, including literally everything from seismic through to production data and experts who had advanced knowledge of modern technology.
Such modern technologies were as follows: –
- Use of New Seismic
- Specialist Production Data Computer Programs for Analysis / Modelling
- Analysis of Original Well Completion Performance
- “Look Ahead” Performance Modelling
- Slim-Hole / Coiled Tubing Drilling
- Modern Water Shut-Off Chemicals
- Velocity Tubes
- How to reduce Surface Back Pressure
- Downhole Technologies as required.
All the fields were analysed in the same way.
They were then compiled per the Operator’s requirements, and all work and data was available electronically.
Finally, at the end of the 6-month contracted period, some 936 billion barrels of “Recoverable Reserves” were established right across the Company’s Asset Portfolio.
In summary, this was an excellent example of creative thinking in terms of a bespoke programme structure in terms of the potential for Brownfield Redevelopment, exceeding, by far the Operator’s expectations. The methodologies utilised are now widely used through the Operator’s other assets.
Who is Dr Michael T. Gibson?
Dr Michael T. Gibson has 40 years in the Oilfield, working initially as a Drilling Engineer when he studied Mechanical and Offshore Engineering at Bachelor’s, Diploma and Master’s, Degree Level at Robert Gordon’s in Aberdeen under the expert tutelage of Professor Blythe McNaughton. He then went on to take a PHD over an 8-year period whilst working offshore as a Drilling Supervisor.
He began teaching / lecturing full-time 15 years ago in many parts of the world for Oil Companies, Drilling Contractors and Universities and has written the vast bulk of Wellideas’ material, ranging from Manuals, Pocket Handbooks, PowerPoints and Videos for the Classroom and Zoom Meetings, through to E-Learning Modules for distance learning.