The effect of gravity on the shape and direction of vertical hydraulic fractures
Saeed SalimzadehCommonwealth Scientific and Industrial Research Organisation (CSIRO), Research Way, Clayton, Vic. 3168, Australia. Email: saeed.salimzadeh@csiro.au
The APPEA Journal 60(2) 668-671 https://doi.org/10.1071/AJ19028
Accepted: 17 February 2020 Published: 15 May 2020
Abstract
Australia has great potential for shale gas development that can reshape the future of energy in the country. Hydraulic fracturing has been proven as an efficient method to improve recovery from unconventional gas reservoirs. Shale gas hydraulic fracturing is a very complex, multi-physics process, and numerical modelling to design and predict the growth of hydraulic fractures is gaining a lot of interest around the world. The initiation and propagation direction of hydraulic fractures are controlled by in-situ rock stresses, local natural fractures and larger faults. In the propagation of vertical hydraulic fractures, the fracture footprint may extend tens to hundreds of metres, over which the in-situ stresses vary due to gravity and the weight of the rock layers. Proppants, which are added to the hydraulic fracturing fluid to retain the fracture opening after depressurisation, add additional complexity to the propagation mechanics. Proppant distribution can affect the hydraulic fracture propagation by altering the hydraulic fracture fluid viscosity and by blocking the hydraulic fracture fluid flow. In this study, the effect of gravitational forces on proppant distribution and fracture footprint in vertically oriented hydraulic fractures are investigated using a robust finite element code and the results are discussed.
Keywords: multiple layers, numerical simulation, shale gas and oil.
Dr Saeed Salimzadeh obtained his PhD in Geomechanics in 2014 from the University of New South Wales (UNSW), Sydney, Australia. He has been a researcher at the Imperial College London, Technical University of Denmark and UNSW. He has been investigating the geomechanical effects and fracture deformation and propagation during subsurface activities in carbon sequestration, reservoir development and production as well as in enhanced geothermal systems. As a Research Scientist at CSIRO Australia, his research focuses on optimising hydraulic fractures for mine preconditioning, in-situ recovery and geothermal systems. |
References
Adachi, J., Siebrits, E., Peirce, A., and Desroches, J. (2007). Computer simulation of hydraulic fractures. International Journal of Rock Mechanics and Mining Sciences 44, 739–757.| Computer simulation of hydraulic fractures.Crossref | GoogleScholarGoogle Scholar |
Economides, M. J., and Nolte, K. G. (2000). ‘Reservoir Stimulation.’ 3rd edn. (Wiley: New York, NY, USA.)
Huang, J., Morris, J. P., Fu, P., Settgast, R. R., Sherman, C. S., and Ryerso, F. J. (2019). Hydraulic-fracture-height growth under the combined influence of stress barriers and natural fractures. SPE Journal 24, 302–318.
| Hydraulic-fracture-height growth under the combined influence of stress barriers and natural fractures.Crossref | GoogleScholarGoogle Scholar |
Jeffrey, R. G., and Mills, K. W. (2000). Hydraulic fracturing applied to inducing longwall coal mine goaf falls. In ‘Pacific Rocks 2000: Rock around the Rim: Proceedings from the Fourth North American Rock Mechanics Symposium, Seattle, USA, 31 July–3 August 2000’. (Ed. J. Girard) pp. 423–430. (A.A. Balkema Publishers: Rotterdam, Netherlands.)
McClure, M. W., and Horne, R. N. (2014). An investigation of stimulation mechanisms in Enhanced Geothermal Systems. International Journal of Rock Mechanics and Mining Sciences 72, 242–260.
| An investigation of stimulation mechanisms in Enhanced Geothermal Systems.Crossref | GoogleScholarGoogle Scholar |
Nejati, M., Paluszny, A., and Zimmerman, R. W. (2015). A disk-shaped domain integral method for the computation of stress intensity factors using tetrahedral meshes. International Journal of Solids and Structures 69–70, 230–251.
| A disk-shaped domain integral method for the computation of stress intensity factors using tetrahedral meshes.Crossref | GoogleScholarGoogle Scholar |
Peters, E., Blöcher, G., Salimzadeh, S., Egberts, P. J. P., and Cacace, M. (2018). Modelling of multi-lateral well geometries for geothermal applications. Advances in Geosciences 45, 209–215.
| Modelling of multi-lateral well geometries for geothermal applications.Crossref | GoogleScholarGoogle Scholar |
Salimzadeh, S., and Nick, H. M. (2019). A coupled model for reactive flow through deformable fractures in Enhanced Geothermal Systems. Geothermics 81, 88–100.
| A coupled model for reactive flow through deformable fractures in Enhanced Geothermal Systems.Crossref | GoogleScholarGoogle Scholar |
Salimzadeh, S., Paluszny, A., and Zimmerman, R. W. (2016). Thermal effects during hydraulic fracturing in low-permeability brittle rocks. In ‘50th US Rock Mechanics/Geomechanics Symposium 2016, Houston, Texas, 26–29 June’. (American Rock Mechanics Association: Alexandria, VA, USA.)
Salimzadeh, S., Grandahl, M., Medetbekova, M., and Nick, H. M. (2019a). A novel radial jet drilling stimulation technique for enhancing heat recovery from fractured geothermal reservoirs. Renewable Energy 139, 395–409.
| A novel radial jet drilling stimulation technique for enhancing heat recovery from fractured geothermal reservoirs.Crossref | GoogleScholarGoogle Scholar |
Salimzadeh, S., Hagerup, E. D., Kadeethum, T., and Nick, H. M. (2019b). The effect of stress distribution on the shape and direction of hydraulic fractures in layered media. Engineering Fracture Mechanics 215, 151–163.
| The effect of stress distribution on the shape and direction of hydraulic fractures in layered media.Crossref | GoogleScholarGoogle Scholar |
