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Wellbore Instability, Stuck Pipe and Drilling Problems

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Wellbore Instability (or borehole instability) is a widely recognised cause of non-productive time during drilling, resulting in stuck pipe, sidetracks and poor hole conditions. In the most extreme cases wellbore instability leads to pre-mature well abandonment and to operators walking away from multi-billion barrel oil and gas fields due to pore pressure and wellbore instability problems: 'not being able to drill down to top reservoir'.

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The stresses acting around the well leading to wellbore instability result in rock failure, which commonly manifests itself as overage hole, breakouts, washouts, spalling, cavings, mud losses, and salt creep. This rock failures can lead to packing off, unplanned torque and drag, mud losses, 'wellbore breathing' or ballooning.

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Wellbore instability during drilling is defined largely by two limits: 

  • high wellbore stresses, resulting in compressive rock failure, or

  • low wellbore stresses, resulting in low fracture gradients and mud losses.

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During production, wellbore instability can result in delayed failure of the reservoir sections resulting in shale failure across the productive intervals and in the failure of productive reservoir formations, resulting in sand production or carbonate solids production.

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During production, as the reservoir pressures depleted, the fracture gradients also decrease, leading to excessive mud losses during late-field in-fill drilling programmes.

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Addis & Yassir have global experience of addressing wellbore stability challenges and optimising drilling plans for successful drilling across the globe, in passive basins such as the GoM, North Slope of Alaska, North Sea and NWS Australia, and compressive regions such as Colombian Andes foothills, Canadian Rockies, and PNG, 

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Publications

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  1. Addis, M.A., Khodaverdian, M., Lee, C.A. and Fehler, D.F. 2005. Slotted Boreholes for Improved Well Stability and Sand Management. ARMA/USRMS 05-789. Proc. Alaska Rocks 2005 Conference, the 40th Symposium on Rock Mechanics (USRMS): Rock Mechanics for Energy, Mineral and Infrastructure Development in the Northern Regions, held in Anchorage Alaska, 25-29th June 2005. 

  2. Hennig, A., Yassir, N., Addis, M.A., and Warrington, A. 2002. Pore pressure estimation in an active thrust region and its impact on exploration and drilling. in A.R. Huffman and G.L. Bowers, eds., Pressure Regimes in sedimentary basins and their prediction: AAPG Memoir 76, pp.89-105.

  3. Addis, M.A., Cauley, M.B. and Kuyken, C. 2001. Brent in-fill drilling programme: Lost circulation associated with drilling depleted reservoirs. SPE/IADC 67741, SPE/IADC Drilling Conf., Amsterdam, 27 Feb – 1st March 2000.

  4. Addis, M.A. and Hennig, A. 1998.  Pore pressure evaluation: differentiating between overpressure and wellbore instability. AADE workshop on “Pore Pressure Regimes in Sedimentary Basins”, Del Lago, September 1998.

  5. Addis, M.A., Choi, X. and Gunning, J.1998. The Influence of the Reservoir Stress-Depletion Response on the Lifetime Considerations of Well Completion Design. SPE/ISRM 47289, Proc. Eurock ’98 Conf., Trondheim, Norway, July 1998.

  6. Addis, M.A., Hanssen, T.H., Willoughby, D.R., Yassir, N. and Enever, J. 1998.  A Comparison of Leak-off Test and Extended Leak-off test data for Stress Estimation. SPE/ISRM 47235, Proc. Eurock ’98 Conf., Trondheim, Norway, July 1998.

  7. Addis, M.A.1997.  The Stress - Depletion Response of Reservoirs. SPE 38720, Proc. 72nd SPE Annual Technical Conference & Exhibition, San Antonio, 5-8 October 1997.

  8. Addis, M.A.1997.  Reservoir depletion and its effect on wellbore stability evaluation. NYRocks ‘97 Conference, 36th U.S. Rock Mechanics Symp., June 1997.

  9. Addis, M.A. and Jeffrey, R.G. 1996.  Slimhole Drilling:  Wellbore Stability considerations based on field and laboratory data.  APPEA Journal1996, pp.544-556.

  10.  Enever, J.R., Yassir, N.A., Willoughby, D.R. and Addis, M.A.1996.  Recent experiences with extended leak-off tests for in-situ stress measurement in Australia.  APPEA Journal1996, pp.528-535.

  11. Addis, M.A.1995.  Wellbore stability: better solutions emerge. E&P Journal, June 1995, pp.12-15.

  12. Addis, M.A.,Last, N.R., Boulter, D, Ramisa-Roca, L. and Plumb, R.A. 1993. The quest for borehole stability in the Cusiana field, Colombia.  Oilfield Review, Vol. 5, No. 2/3, April/July 1993, pp.33-43.

  13. Rawlings, C.G., Barton, N.R., Bandis, S.C., Addis, M.A. and Gutierrez, M.S. 1993.  Laboratory and numerical discontinuum modelling of wellbore stability during drilling in low-permeability reservoirs.  SPE Paper 25869, SPE Rocky Mountain Regional Low Permeability Reservoirs Symp., Denver, April 1993.

  14. Addis, M.A. and Wu, B. 1993.  The role of the intermediate stress in wellbore stability:  Evidence from hollow cylinder tests.  U.S. Rock Mechanics Symp:  Rock Mechanics in the 1990s, Madison, Wisconsin, June 1993, B. Haimson (ed.), Vol. 1, pp.57-60.

  15. Ringstad, C., Addis, M.A.,Brevik, I., and Santarelli, F.J. 1993.  Scale effects in hollow cylinder tests.  Scale Effects in Rock Masses, ed. Pinto da Cunha, Balkema.

  16. Addis, M.A.,Barton, N.R., Bandis, S.C. and Henri, J.P. 1990.  Laboratory studies on the stability of vertical and deviated wellbores.  SPE Paper 20406, 65th Annual SPE Conference, New Orleans, September 1990.

  17. McLean, M.R. and Addis, M.A. 1990.  Wellbore stability:  the effect of strength criteria on mud weight recommendations.  SPE Paper 20405, 65th Annual SPE Conference, New Orleans, September 1990.

  18. McLean, M.R. and Addis, M.A.1990.  Wellbore stability:  A review of current methods of analysis and their field application.  IADC/SPE Paper 19941; IADC/SPE Drilling Conference, Houston, February 1990.

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