کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5786318 | 1640482 | 2017 | 14 صفحه PDF | دانلود رایگان |
- A novel three-dimensional fracture propagation model based on the discrete element method.
- Prediction of hydraulic fracture geometry in the high dip angle shale formation.
- Fracturing tests were performed on large size natural shale specimens.
Strike-slip fault geostress and dipping laminated structures in Lujiaping shale formation typically result in difficultly predicting hydraulic fracture (HF) geometries. In this study, a novel 3D fracture propagation model based on discrete element method (DEM) is established. A series of simulations is performed to illustrate the influence of vertical stress difference (â³Ïv = ÏvâÏh), fluid viscosity, and injection rate, on HF growth geometry in the dipping layered formation. Results reveal that the fracturing fluid can easily infiltrate the dipping bedding plane (BP) interfaces with low net pressure for â³Ïv = 1 MPa. HF height growth is also restricted. With increased â³Ïv, fracture propagation in the vertical direction is enhanced, and a fracture network is formed by VF and partially opened dipping BPs. However, it is likely to create simple VF for â³Ïv = 20 MPa. Appropriately increasing fracturing fluid viscosity and injection rate is conductive to weakening the containment effect of BPs on HF growth by increasing the fluid net pressure. However, no indication is found on whether a higher fracturing fluid viscosity is better. Higher viscosity can reduce the activation of BPs, so a stimulated reservoir volume is not necessarily increased. All these results can serve as theoretical guidance for the optimization of fracturing treatments in Lujiaping shale formation.
Journal: Journal of Structural Geology - Volume 98, May 2017, Pages 53-66