| dc.description.abstract | In hydraulic fracturing stimulation treatments for organic-rich mudrocks, some issues that pose challenges in pre-completions design include selection of intervals for stimulation treatment, and selection of proppants for stimulation design. After the stimulation treatment, a key post-completions issue is the detection of the fracture and evaluation of the fracture performance. The application of petrophysical and geophysical analysis can offer potential solutions to these issues, thereby lead to improvements of both pre-completions and post-completions design of the hydraulic fracturing treatment.
The objectives of this dissertation are (a) to introduce a rock classification workflow, which integrates geologic, petrophysical and geomechanical analysis, for the determination of zones for fracture stimulation treatments, (b) to develop a new technique for characterization of mechanical damage in proppant packs to improve the selection of proppants for stimulation treatment, and (c) to investigate the use of nanoparticles as contrast agents that enhances magnetic susceptibility measurements for the detection of hydraulic fractures after stimulation treatments.
I first demonstrated that the integrated rock classification workflow, which includes geologic attributes of the formation, in-situ stress assessment capturing the effects of anisotropy in organic-rich mudrocks, and also takes into account anisotropic poroelastic coefficients, can improve the selection strategy for completion zones. Next, I introduced the application of the Hertz-Mindlin granular contact model to approximate the effective elastic properties of proppant packs. I used the calibration parameters of the Hertz-Mindlin model to develop correlations for the prediction of weight percentage of crushed proppants. Finally, from laboratory investigations, I demonstrated that superparamagnetic nanoparticles when mixed with proppants enhance the reliability of detecting fractures using magnetic susceptibility measurements. I also presented the sensitivity of the magnetic susceptibility measurements to the composition of proppants, concentration of nanoparticles, and the width of the induced fractures.
The outcomes of this dissertation demonstrate significant contribution of petrophysical and geophysical analysis in achieving better fracture performance from completions design. Better fracture performance can be achieved by improving the strategies for identifying prolific zones for fracture initiation and propagation, achieving good fracture conductivity from the selection of proppants, and analyzing post-fracture performance of hydraulic fracturing treatments. These improvements could in turn result in improved rates and recoveries from organic-rich mudrock formations. | en |
