Orientation of Hydraulic Fracture Initiation from Perforated Horizontal Wellbores
- Authors
- Andreas Michael (Louisiana State University)
- DOI
- https://doi.org/10.2118/199766-STU
- Document ID
- SPE-199766-STU
- Publisher
- Society of Petroleum Engineers
- Source
- SPE Annual Technical Conference and Exhibition, 30 September - 2 October, Calgary, Alberta, Canada
- Publication Date
- 2019
- Document Type
- Conference Paper
- Language
- English
- ISBN
- 978-1-61399-663-8
- Copyright
- 2019. Society of Petroleum Engineers
- Disciplines
- Keywords
- Downloads
- 19 in the last 30 days
- 6,223 since 2007
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The orientation of hydraulic fractures controls the productivity from hydrocarbon reservoirs. Productivity from low permeability formations is greatly improved having multiple fractures oriented transversely rather than longitudinally, relative to a horizontal wellbore. Analytical approximations from the literature for the longitudinal and transverse fracturing stresses are modified to incorporate pore pressure effects and then used to develop a criterion for the orientation of fractures initiating from perforated wells. The validity of this criterion is assessed numerically and is found to overestimate transverse fracture initiation, which occurs under a narrow range of conditions; when the formation tensile strength is below a critical value and the breakdown pressure within a "window."
In horizontal wells, it is easier to achieve longitudinal fracture initiation, as transverse fracture initiation only occurs over a narrow wellbore pressure-at-breakdown window, while longitudinal fracture initiation occurs at comparatively higher wellbore pressures. The numerical study shows that in contradiction with existing analytical approximations, the tangential stress which induces transverse fracture initiation, is a stronger function of wellbore pressure just as the stress inducing longitudinal fracture initiation is. This reduces the breakdown pressure window for transverse fracture initiation compared to what the derived analytical approximations predict. Furthermore, this creates an additional constraint for transverse fracture initiation; the critical tensile strength value, which determines the maximum tensile strength for which transverse fracture initiation is possible for a given stress state.
The range of the in-situ stress states where transverse fracture initiation is promoted can be visualized in dimensionless plots for perforated wells. This is useful for completion engineers; when targeting low permeability formations, wells must be made to induce multiple transverse fractures. A numerical simulation scheme performed on several stress states demonstrates frequent occurrence of longitudinal fracture initiation, implying that the propagating fracture re-orients in the near-wellbore region to become aligned perpendicular to the least compressive in-situ principal stress. This is the cause of near-wellbore tortuosity, which in turn is a cause completions and production-related problems, such as early screenouts and post-stimulation well underperformance.
| File Size | 1 MB | Number of Pages | 23 |
Balen, R. M., Mens, H.-Z., & Economides, M. J. (1988). Applications of the Net Present Value (NPV) in the Optimization of Hydraulic Fractures. Society of Petroleum Engineers. doi:10.2118/18541-MS.
Barree, R. D., and Miskimins, J. L. (2015). Calculation and Implications of Breakdown Pressures in Directional Wellbore Stimulation. Society of Petroleum Engineers. February 3. doi:10.2118/173356-MS.
Byerlee, J. D. (1978). "Friction of Rocks." Pure and Applied Geophysics PAGEOPH, vol. 116, no. 4-5, 1978, pp. 615-626., doi:10.1007/bf00876528.
Daneshy, A. A. (1973). A Study of Inclined Hydraulic Fractures. Society of Petroleum Engineers. April 1. doi:10.2118/4062-PA.
Deimbacher, F. X., Economides, M. J., and Jensen, O. K. (1993). Generalized Performance of Hydraulic Fractures With Complex Geometry Intersecting Horizontal Wells. Society of Petroleum Engineers. doi:10.2118/25505-MS.
Economides, M., and Martin, A. N. (2010). How To Decide Between Horizontal Transverse, Horizontal Longitudinal, and Vertical Fractured Completions. Society of Petroleum Engineers. doi:10.2118/134424-MS.
El Rabaa, W. (1989). Experimental Study of Hydraulic Fracture Geometry Initiated From Horizontal Wells. Society of Petroleum Engineers. doi:10.2118/19720-MS.
Hossain, M. M., et al. (2000), "Hydraulic Fracture Initiation and Propagation: Roles of Wellbore Trajectory, Perforation and Stress Regimes." Journal of Petroleum Science and Engineering, vol. 27, no. 3-4, pp. 129-149., doi:10.1016/s0920-4105(00)00056-5.
"Itasca Consulting Group." Software | Itasca Consulting Group, www.itascacg.com/software.
Koskella, Dave, et al. "Northside: Observation from an Underground Laboratory: An Integrated Approach to Unlocking Performance in the Niobrara." SPE-GCS, Noble Energy, Inc., 21 Jan. 2015, www.spegcs.org/events/2713/.
Kurdi, M. (2018, September 24). A New Computational Model to Predict Breakdown Pressures in Cased and Perforated Wells in Unconventional Reservoirs. Society of Petroleum Engineers. doi:10.2118/194038-STU.
Lee, H. P., J. E. Olson, J. Holder, J. F. W. Gale, and R. D. Myers (2015). The interaction of propagating opening mode fractures with preexisting discontinuities in shale, J. Geophys. Res. Solid Earth, 120, 169-181, doi:10.1002/2014JB011358.
Michael, A. (2014). Economic Implications Of The Current Geopolitical Forces Vis-à-vis Hydrocarbons On Global Energy Markets. Society of Petroleum Engineers. May 19. doi:10.2118/169832-MS.
Michael, A. (2016). Financial Impact of Price Volatility on the Oilfield Services Sector of the Petroleum Industry. May 10. Society of Petroleum Engineers. doi:10.2118/179962-MS.
Michael, A. (2019). The Net Present Value of a Hydraulic Fracture Treatment. Society of Petroleum Engineers. The Way Ahead, www.spe.org/en/twa/twa-article-detail/?art=5557
Michael, A., and Gupta, I. (2019). Orientation of Fracture Initiation in Poroelastic Media: Application in Unconventional Reservoirs. Society of Petroleum Engineers. doi:10.2118/195494-MS.
Nelson, E. J., et al. (2005). "Transverse Drilling-Induced Tensile Fractures in the West Tuna Area, Gippsland Basin, Australia: Implications for the in Situ Stress Regime." International Journal of Rock Mechanics and Mining Sciences, vol. 42, no. 3, April, pp. 361-371., doi:10.1016/j.ijrmms.2004.12.001.
Rybacki, E., et al. "What Controls the Mechanical Properties of Shale Rocks? â?" Part I: Strength and Young's Modulus." Journal of Petroleum Science and Engineering, vol. 135, 2015, pp. 702-722., doi:10.1016/j.petrol.2015.10.028.
