LWD Formation Pressure Testing Allows Decision-Making While Drilling

Author(s):  
Ulrich Hahne ◽  
Aravindh Kaniappan ◽  
Jos Pragt ◽  
Arno Buysch
2021 ◽  
Author(s):  
Atul Kumar Anurag ◽  
Adel Alkatheeri ◽  
Alvaro Sainz ◽  
Khalid Javid ◽  
Yaxin Liu ◽  
...  

Abstract This paper discusses a holistic combination of advanced formation evaluation techniques with pressure testing and reservoir navigation services to mitigate uncertainty related challenges in real time and successfully drill & place ERD laterals targeting Jurassic carbonate reservoirs. A meticulously planned approach to navigate the well trajectory by tracking the desired properties, informed decision-making while drilling and accurate data acquisition for aiding appropriate selection and placement in-flow control device (ICD) in lower completion design and future reservoir management contributed to the success of these complex wells in carbonate reservoirs. The first well in this study, involved drilling and evaluating a long lateral section as single oil producer targeting a carbonate reservoir. While no tar presence was expected, a combination of density, neutron porosity and nuclear magnetic resonance (NMR) logs while drilling resulted in identifying a deficit NMR porosity when compared to density porosity. Deployment of a formation pressure testing while drilling (FPWD) tool enabled measurement of the formation mobility and validate the presence of a tar. Using the same combination of measurements in the subsequent wells for delineating the tar enabled accurate planning of injection wells on the periphery of the field. Approximately 3 days were saved compared to the first well where the drill string had to be POOH to run-in with FPWD service. Hence, having FPWD tool in the same string helped in confirming the formation mobility in real time to call for critical decision making like changing the well trajectory or calling an early TD. Across all the wells drilled in this field, the formation pressure, mobility and porosity measurements provided valuable input for optimum ICD placement and design. Successful identification of unexpected tar resulted in substantial rig time savings, accurate planning of asset utilization and added confidence in design and placement of lower completions by utilizing LWD data. Benefits of integrated data and services combination became clear for applications involving advanced reservoir characterization and enhanced well placement in complex carbonate reservoirs. From the offset wells, a tar was seen in deeper formations but the integration of LWD NMR and mobility data from this well confirmed the presence of a tar within the zone of interest. The study established a cost-effective workflow for mitigating uncertainties related to tar encountered while drilling extreme ERD laterals in an offshore environment where any lost time results in significant increase in expenditures during the development phase. A systematic approach to tackle these uncertainties along with acquisition of critical data for the design & placement of completion results in optimum production from the reserves.


2004 ◽  
Author(s):  
S. Frank ◽  
V.J. Beales ◽  
S. Dilling ◽  
M. Meister ◽  
J. Lee ◽  
...  

2019 ◽  
Author(s):  
Victor Imomoh ◽  
Chidi Ndokwu ◽  
Kenneth Amadi ◽  
Oluwaseun Toyobo ◽  
Ikechukwu Nwabueze ◽  
...  

2006 ◽  
Author(s):  
Ulrich Hahne ◽  
Jos Pragt ◽  
Martin Leonard Venier ◽  
Matthias Meister ◽  
Jenson Jit-Chang Tan ◽  
...  

2003 ◽  
Author(s):  
M. Meister ◽  
J. Lee ◽  
V. Krueger ◽  
D. Georgi ◽  
R. Chemali

2011 ◽  
Vol 28 (2) ◽  
pp. 478-492 ◽  
Author(s):  
Brian Anderson ◽  
Steve Hancock ◽  
Scott Wilson ◽  
Christopher Enger ◽  
Timothy Collett ◽  
...  

2021 ◽  
Author(s):  
Yamal Askoul ◽  
◽  
Gavin JG Sibbald ◽  
Art Hooker ◽  
John Banks ◽  
...  

The necessity of knowing formation pressure is crucial to classifying pressure regimes for better understanding in well planning and to de-risk potential abnormal pressure conditions before any future field development wells are drilled, consequently minimizing operational cost. Wireline formation pressure testing has been a useful and reliable technology, that has evolved to confront the challenge of ultra-low permeable reservoir conditions by innovating and improving pump capability, accuracy in pressure measurements, automated control and the implantation of Formation Rate Analysis (FRA) intertwined with an Artificial Intelligent tool. In any pressure testing, the key factor is to be able to withdraw volume from the formation to generate a disturbance on formation pore pressure that a pressure gauge can measure. In the past this has been a difficult task in ultra-low permeable zones. The new generation of wireline tools are capable of withdrawing volume from ultra-low permeable reservoirs, with mobilities lower than 0.01mD/cP. This has been made possible by utilizing control of the pump speed down to 0.0003cc/s which then gives the operator the ability to test ultra-tight formations without the need for inflatable packers. By pulling down the pressure at an extremely low rate and using Artificial Intelligence to control the rate by knowing the formation rate, a proportional amount of volume can be extracted without calling it a tight test. During the operation by observing the rate, and making sure the pump is not oscillating, which indicates the formation rate is lower than the lowest rate the pump can withdraw, the test can be validated for formation flow and the pressure transient of the build – up can be analysed to confirm that at least spherical flow is observed. Once reservoir communication has been confirmed and by analysing drawdown and build-up pressure versus volume withdrawn and implementing the FRA equation, the reservoir pressure can be back calculated by considering isothermal compressibility and FRA slope. This paper highlights the best technical approach to quality check and quality control these tests, showing examples of various wells, where the technique has been used to predict a formation pressure, which can be used for further use for field development, drilling optimisation and production profiles. These pressures would never have been possible using static rates and volume.


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