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The geological complexities of shale formations dominated by lamination deposition mechanisms make formation evaluation a challenge for hydraulic fracture operations. Logging While Drilling technologies have evolved to provide valuable information for a reliable approach in anisotropic shales. One of the most frequent considerations is well productivity and how the new technologies and evaluation methods can help to mitigate the uncertainty of the completion and improve fracturing performance. The incorporation of the TIV anisotropy evaluation from LWD azimuthal acoustic measurements can help characterize the impact of the laminations stage by stage or even a more detailed cluster by cluster analysis. Information from the LWD azimuthal sonic tool can help provide a better understanding in regards to the rock mechanical behavior in horizontal shale wells, as well as the brittleness interpretation providing a more realistic approach to the lamination structure of the shale deposition. Quantifying TIV anisotropy is a very important key evaluation factor to optimize the completion program likewise the well productivity. In conjunction with the LWD azimuthal sonic information, the LWD spectral gamma ray measures isotope concentrations (such as Uranium, Potassium, and Thorium) can be confidently integrated into the unconventional petrophysical interpretation calculations of Total Organic Content. This analysis is incorporated with the geomechanical and anisotropy evaluation to select the best fracture placement and design in an unconventional environment. The anisotropic brittleness analysis identifies the zones where the best fracture propagation will be achieved while the petrophysical analysis indicates how productive these fractures should be. Through the geometric fracture simulation the best set of recommendations for the fracturing operation are developed to predict the conductivity area which contributes to the well productivity. This paper will show the impact of the TIV anisotropy into the geomechanical evaluation, beginning with the unique real-time fracture placement methodology leading to an optimization of the anisotropy analysis to generate the best frac design to avoid expensive completion programs and reduce uncertainty on fracture placement evaluation.

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A real-time wellbore stability analysis capability was developed to help an operator reduce high costs of nonproductive time (NPT) in an area prone to stuck pipe, lost borehole assemblies (BHAs), and lost hole sections. A multidisciplinary team created integrated processes for predrill, dynamic real-time, and post-drill modeling to help identify wellbore instability and pore pressure events that cause kicks, tight holes, and stuck pipe incidents. A Predrill wellbore stability model for the proposed well was built based on offset well data. The model enabled the identification of depth intervals and formations where there are potential wellbore stability issues. A multidisciplinary team consisting of geomechanics engineers, pore pressure specialists and drilling optimization engineers provided 24-hour monitoring of drilling parameter trends and analyzed quad-combo logging-while-drilling (LWD) data in real time to determine the health of the wellbore. This enabled calibration of the predrill model in real time, which consequently served as an ahead-of-bit prediction of undrilled sections of the well. Four wells were drilled in this project. The first two wells had lost hole sections resulting from wellbore stability challenges that caused high NPT costs. The new process was instituted on the third well which resulted in no lost time due to troubled hole sections and subsequently resulting in 30% lower well cost due to reduction in expected NPT. The same results were achieved on the fourth well, which demonstrated repeatability of the new process. The predrill model indicated that a pore pressure ramp was expected and that the operator's planned mudweight and casing program posed potential risks of formation fluid influx and hole breakout with resultant cavings falling into the wellbore. During drilling operations the expected pressure ramp was confirmed by an observed increase in connection gas and cavings across the depth intervals identified in the predrill model. This was communicated to the operator and informed their timely decision to increase the mud weight range for the hole interval and to set the casing shallower than planned to avoid potential hole problems. This multidisciplinary approach to address well challenges by integrating technology, tailored expert response, and collaboratively managed delivery helps to reduce uncertainty, improve safety, and increase efficiency of planned wells and depth intervals. The new process comprising predrill, dynamic real-time, and post-drill phases identifies drilling hazards for correct mitigation. Lessons learned during the drilling operations are documented and applied to subsequent wells for continued improvement of operational parameters and best practices.