Authors: Younessi, A; Rasouli, V

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Younessi, A & Rasouli, V 2008, 'Representing a Rock Engineering System to Analyse Wellbore Instability Due to Fracture Reactivation', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), SHIRMS 2008: Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium, Australian Centre for Geomechanics, Perth, pp. 381-394,

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In drilling practices, as the wellbore is the only route to transfer the produced hydrocarbon to the surface, the instability of the wellbore during drilling and production is a major concern. Sliding failure along the fractures (especially faults) that intersect the wellbore is one of the wellbore instability mechanisms. Here, in comparison with the slope stability, a well known phenomenon in mining and civil industry, during drilling process the drilling mud can penetrate through the discontinuities, and during production, the reservoir depletion causes changes in the horizontal stress magnitudes. Both of these effects could lead to the fracture reactivation and wellbore instability. The rock engineering systems (RES), initially introduced in mining and civil related geomechanics field, is an approach to analyse the interrelationship between the parameters playing in the wellbore failure mechanisms. In this study, after discussing all the failure mechanisms in a wellbore, and identifying all the effective parameters in wellbore instabilities, an interaction matrix is introduced to study the failure mechanism, particularly the sliding failure mechanism. Thereafter, the interaction intensity and dominance of each principal parameter in the system is established to classify the parameters. The other aspect of the systems approach is establishing when positive feedback within the system can occur, which leads to instabilities. The results indicate the ability of this method to analyse the wellbore instability with regard to fracture reactivation mechanism and help to find a better engineering action to mitigate or eliminate instabilities.

Aadnoy, B.S. and Hansen, A.K. (2004) Bounds on in-situ stress magnitudes improve wellbore stability analyses. The IADC/SPE Drilling Conference, Dallas, 2–4 March.
Addis, M.A., Last, N.C. and Yassir, N.A. (1994) The estimation of horizontal stresses at depth in faulted regions and their relationship to pore pressure variation, in Rock mechanics in petroleum engineering, Eurock 1994 proceedings, A.A. Balkema, Rotterdam, pp. 887–895.
Bratton, T., Bornemann, T., Li, Q., Plumb, D., Rasmus, J. and Hess, A. (1999) Logging-while-drilling images for geomechanical, geological and petrophysical interpretations. SPWLA 40th Annual Logging Symposium, Oslo, Norway, paper JJJ.
Chen, X., Chen, X., Tan, C.P. and Haberfield, C.M. (1996) Wellbore stability analysis guidelines for practical well design. The SPE Asia Pacific Oil and Gas Conference, Adelaide, South Australia, 28–31 October.
Cuss, R.J., Rutter, E.H. and Holloway, R.F. (2003) Experimental observations of the mechanics of borehole failure in porous sandstone. International Journal of Rock Mechanics and Mining Sciences, Vol. 40, pp. 747–761.
Dusseault, M.B., Bruno, M.S. and Barrera, J. (2001) Casing shear: causes, cases, cures. The SPE International Oil and Gas Conference, Beijing, 2–6 November.
Hawkes, C.D. and McLellan, P.J. (2002) Coupled modeling of borehole instability and multiphase flow for underbalanced drilling. The IADC/SPE Drilling Conference, Dallas, Texas, 26–28 February.
Hudson, J.A. (1992) Rock engineering systems: theory and practice. Ellis Horwood, Chichester.
Jaeger, J.C. and Cook, N.G.W. (2007) Fundamentals of rock mechanics. Chapman and Hall.
Maury, V. (1994) Rock failure mechanisms identification: a key for wellbore stability and reservoir behavior problem. Eurock 1994, pp. 175–182.
Mazzoccola, D.F. and Hudson, J.A. (1996) A comprehensive method of rock mass characterization for indicating natural slope instability. Quarterly Journal of Engineering Geology, 29, pp. 37–56.
Gil, I.R., Ramos, R., Montgomery, C.T., Ormark, K. and Soerensen, C. (2005) Failure mechanisms in deepwater chalks rock stability as function of pore pressure and water saturation. International Petroleum Technology Conference, Doha, Qatar, 21–23 November.
Moos, D. (2001) Wellbore stability in deep water-handling geomechanical uncertainty. The AADE National Drilling Conference, Drilling Technology – The Next 100 years, Houston, Texas, 27–29 March.
Rhett, D.W. and Risnes, R. (2002) Predicting critical borehole pressure and critical reservoir pore pressure in pressure depleted and repressurized reservoirs. SPE/ISRM Rock Mechanics Conference, Irving, Texas, 20–23 October.
Streit, J.E. and Hillis, R.R. (2004) Estimating fault stability and sustainable fluid pressure for underground storage of CO2 in porous rock. Energy 29, pp. 1445–1456.
Tare, U.A. and Mody, F.K. (2002) Managing borehole stability problems: on the learning, unlearning and relearning curve. The AADE 2002 Technology Conference. Drilling and Completion Fluids and Waste Management, Texas, 2–3 April.
Zhang, J., Bai, M. and Roegiers, J. (2003) Dual-porosity poroelastic analyses of wellbore stability. International Journal of Rock Mechanics and Mining Sciences, Vol. 40, pp. 473–483.

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