A study of hydraulic fracture height for Achimov formation based on anisotropic geomechanical model (Harvutinskaya area)

Introduction. The development of tight reservoirs is a technological challenge that needs synergetic work. This paper allows the results of the study of anisotropic elastic properties and stress state condition of the Achimov formation (AchS10, AchS12) related to the Harvutinskaya oil field.

Aim. The main goal of this research work was to choose the hydraulic fracture technology based on geomechanical modeling. That takes into account anisotropic elastic properties and stress state to determine the fracture height.

Materials and methods. A complex study program in the well was realized that includes sonic logging data in open hole and a` er hydraulic stimulation, thermometry after mini-hydraulic fracturing and after the main stage of hydraulic fracturing, pulsed neutron gamma ray imaging (NRT—non-radioactive propant), a study of VTI anisotropy, and the last one was a strength profile.

Results. A geomechanical model with anisotropic elastic properties and stresses was introduced. In the result, hydraulic fracture design was performed and validated on real study data from fracture high analysis.

Conclusion. A complex study allowed us to receive a full understanding of the Achimov formation stress state in the Xarvutinskaya area and choose eff ective stimulation technology based on isotropic and anisotropic geomechanical models.

1. Alkhimenkov Yu. A., Bayuk I.O. Applicability of the Thomsen Parameters to fractured carbonate reservoir rocks // Seismic Technologies, № 4, 2013, p. 36–48.

2. Higgings S., Goodwin S., Donald Q., Donald A., Bratton T., Tracy G. Anisotropic stress models improve completion design in the Baxter shale, In Proceedings of SPE ATCE, Denver, 21–24 September, 2008, SPE 115736.

3. Kefei Lu. Gas Shale Anisotropy and Mechanical Property: Laboratory Measurements and Mathematical Modeling. 2016, PhD, University of Houston.

4. King M. Static and dynamic moduli of rocks under pressure, in Somerton, W., and H. Ed. Rock mechanics-theory and practices. In Proceedings of 11th symposium of rock mechanics. 1969, University of Calif., Berkeley, 329–351.

5. Waters G., Lewis R., Bently D. The eff ect of mechanical properties anisotropy in the generation of hydraulic fractures in organic shales. In Proceedings of SPE ATCE, Denver, 2011. 30 Oct–2 Nov, SPE 146776.

6. Higgings S., Goodwin S., Donald Q., Donald A., Bratton T., Tracy G. Anisotropic stress models improve completion design in the Baxter shale, In Proceedings of SPE ATCE, Denver, 2008, 21–24 September, SPE 115736.

7. Zoback M.D., Kohli A.H. Composition, Fabric, Elastic Properties and Anisotropy from Part I — Physical Properties of Unconventional Reservoirs. 2019.

8. Duenckel R.J., Smith H.D., Warren W. et al. 2011. Field Application of a New Proppant Detection Technology. Presented at the SPE Annual Technical Conference and Exhibition, Denver, 30 October–2 November. SPE-146744-MS.