Proppant Diagenesis in Carbonate-Rich Eagle Ford Shale Fractures
- Ahmed M. Elsarawy (Texas A&M University) | Hisham A. Nasr-El-Din (Texas A&M University)
- Document ID
- Society of Petroleum Engineers
- SPE Drilling & Completion
- Publication Date
- September 2020
- Document Type
- Journal Paper
- 465 - 477
- 2020.Society of Petroleum Engineers
- proppant, fluid interaction, fracturing
- 26 in the last 30 days
- 100 since 2007
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Proppant diagenesis occurs when minerals form on the proppant surface and/or around the embedment crater at high-temperature and/or high-stress conditions (Weaver et al. 2005). It has been used recently to explain low fracture conductivity in the field as well as the long-term downward trend of laboratory-measured American Petroleum Institute conductivity data (Liang et al. 2015). However, researchers disagree about the source of such overgrowth minerals and the involvement of proppant in the process. In addition, the diagenesis process has not been investigated in the case of carbonate-rich shale formations. Therefore, the objectives of this paper are to experimentally investigate the proppant diagenesis process during hydraulic fracturing of the Eagle Ford Shale Formation and to determine the role of the proppant in the process.
Diagenesis was studied after aging a mixture of proppant and formation samples in deionized water for 3 weeks at 325°F and 300 psia. Outcrop cores of the Eagle Ford Shale Formation were crushed and sieved to 50/100 US-mesh size. The ceramic, sand, and resin-coated-sand (RCS) proppants of 20/40 US-mesh size were tested. The proppant surface was studied for mineral overgrowth and/or dissolution before and after aging using scanning electron microscope (SEM) with energy-dispersive X-ray spectroscopy (EDS). The concentration of the cations leached into the solution was measured by analyzing the supernatant samples using inductively coupled plasma (ICP)/optical-emission spectroscopy, while the sulfate-ion concentration was measured using a spectrophotometer. The proppants and the Eagle Ford Shale Formation samples were analyzed after aging separately at the same conditions to explain the sources of the leached ions and the observed overgrowth and/or precipitated minerals.
The Eagle Ford Shale was found to be the source of calcium sulfate and calcium zeolite precipitates because of dissolution/precipitation reactions with water. Only the ceramic proppant was found to induce an additional mineral overgrowth of iron calcium zeolite on its surface. Conversely, the sand and RCS proppants did not encounter any precipitates/overgrowth minerals. These proppants only changed the elemental composition of the precipitated zeolite from the formation/fluid interaction, showing increased silicon and decreased calcium and aluminum concentrations. The proppant dissolution was observed with all types of proppants, as indicated by the presence of silicon ions in the solution after aging. A thermodynamic modeling study was conducted and confirmed the possibility of formation of the observed precipitate and overgrowth minerals at the equilibrium state of the rock and proppant mixture in water. Finally, the breaking and peeling of the phenol formaldehyde resin from the RCS proppant particles at static conditions was observed for the first time (to the best of the authors’ knowledge) using the SEM technique.
The study contributes to the understanding of the scale formation and the mechanisms that damage fracture conductivity in the Eagle Ford Shale. Results impact the choice of fluid and proppant for fracturing optimization and long-term production sustainability in the Eagle Ford Shale reservoirs.
|File Size||20 MB||Number of Pages||13|
Aven, N. K., Weaver, J., Loghry, R. et al. 2013. Long-Term Dynamic Flow Testing of Proppants and Effect of Coatings. Paper presented at the SPE European Formation Damage Conference and Exhibition, Noordwijk, The Netherlands, 5–7 June. SPE-165118-MS. https://doi.org/10.2118/165118-MS.
Becq, D. F., Claude, R., and Sarda, J. P. 1984. High-Strength Proppants Behavior under Extreme Conditions. Paper presented at the SPE Formation Damage Control Symposium, Bakersfield, California, USA, 13–14 February. SPE-12487-MS. https://doi.org/10.2118/12487-MS.
Duenckel, R., Conway, M. W., Eldred, B. et al. 2012. Proppant Diagenesis—Integrated Analyses Provide New Insights into Origin, Occurrence, and Implications for Proppant Performance. SPE J. 27 (2): 131–144. SPE-139875-PA. https://doi.org/10.2118/139875-PA.
Elsarawy, A. M. and Nasr-El-Din, H. A. 2018a. Propped Fracture Conductivity in Shale Reservoirs: A Review of Its Importance and Roles in Fracturing Fluid Engineering. Paper presented at the KSA Annual Technical Symposium and Exhibition, Dhahran, Saudi Arabia, 23–26 April. SPE-192451-MS. https://doi.org/10.2118/192451-MS.
Elsarawy, A. M. and Nasr-El-Din, H. A. 2018b. An Experimental Investigation of Proppant Diagenesis and Proppant-Formation-Fluid Interactions in Hydraulic Fracturing of Eagle Ford Shale. Paper presented at the SPE Trinidad and Tobago Energy Resources Conference, Port of Spain, Trinidad and Tobago, 25–26 June. SPE-191225-MS. https://doi.org/10.2118/191225-MS.
Helgeson, H. C., Kirkham, D. H., and Flowers, G. C. 1981. Theoretical Prediction of the Thermodynamic Behavior of Aqueous Electrolytes at High Pressures and Temperatures—Parts I through IV. Am J Sci 281: 1249–1516. https://doi.org/10.2475/ajs.274.10.1089.
Lafollette, R. F. and Carman, P. S. 2010. Proppant Diagenesis: Results So Far. Paper presented at the SPE Unconventional Gas Conference, Pittsburgh, Pennsylvania, USA, 23–25 February. SPE-131782-MS. https://doi.org/10.2118/131782-MS.
Lafollette, R. F. and Carman, P. S. 2011. Long-Term Stability of Proppants Exposed to Harsh Shale Reservoir Conditions. Paper presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, Texas, USA, 24–26 January. SPE-140110-MS. https://doi.org/10.2118/140110-MS.
Lee, D. S., Elsworth, D., Yasuhara, H. et al. 2009. An Evaluation of the Effect of Fracture Diagenesis on Fracture Treatments: Modeled Response. Paper presented at the 43rd US Rock Mechanics Symposium and 4th US-Canada Rock Mechanics Symposium, Asheville, North Carolina, USA, 28 June–1 July. ARMA-09-104.
Lee, D. S., Elsworth, D., Yasuhara, H. et al. 2010. Experiment and Modeling to Evaluate the Effects of Proppant-Pack Diagenesis on Fracture Treatments. J Pet Sci Eng 74: 67–76. https://doi.org/10.1016/j.petrol.2010.08.007.
Liang, F., Sayed, M., Al-Muntasheri, G. et al. 2015. Overview of Existing Proppant Technologies and Challenges. Paper presented at the SPE Middle East Oil and Gas Show and Conference, Manama, Bahrain, 8–11 March. SPE-172763-MS. https://doi.org/10.2118/172763-MS.
McDaniel, B. W. and Hoch, O. F. 1988. Realistic Proppant Conductivity Data Improves Hydraulic Fracturing Treatment Design. J Can Pet Technol 27 (4): 62–68. PETSOC-88-04-10. https://doi.org/10.2118/88-04-10.
Nguyen, P. D., Weaver, J. D., and Rickman, R. D. 2008. Prevention of Geochemical Scaling in Hydraulically Created Fractures: Laboratory and Field Studies. Paper presented at the SPE Eastern Regional/AAPG Eastern Section Joint Meeting, Pittsburgh, Pennsylvania, USA, 11–15 October. SPE-118175-MS. https://doi.org/10.2118/118175-MS.
Penny, G. S. 1987. An Evaluation of the Effects of Environmental Conditions and Fracturing Fluids upon the Long-Term Conductivity of Proppants. Paper presented at the SPE Annual Technical Conference and Exhibition, Dallas, Texas, USA, 27–30 September. SPE-16900-MS. https://doi.org/10.2118/16900-MS.
Raysoni, N. and Weaver, J. 2012. Improved Understanding of Proppant-Formation Interactions for Sustaining Fracture Conductivity. Paper presented at the SPE Saudi Arabia Section Technical Symposium and Exhibition, Al-Khobar, Saudi Arabia, 8–11 April. SPE-160885-MS. https://doi.org/10.2118/160885-MS.
Raysoni, N. and Weaver, J. 2013. Long-Term Hydrothermal Proppant Performance. SPE Prod & Oper 28 (4): 414–426. SPE-150669-PA. https://doi.org/10.2118/150669-PA.
Santos, E. C. D., Silva, J. C. M., and Duarte, H. A. 2016. Pyrite Oxidation Mechanism by Oxygen in Aqueous Medium. J Phys Chem C 120 (5): 2760–2768. https://doi.org/10.1021/acs.jpcc.5b10949.
Weaver, J. D., Nguyen, P. D., Parker, M. A. et al. 2005. Sustaining Fracture Conductivity. Paper presented at the SPE European Formation Damage Conference, Scheveningen, The Netherlands, 25–27 May. SPE-94666-MS. https://doi.org/10.2118/94666-MS.
Weaver, J. D., Parker, M., Van Batenburg, D. et al. 2007. Fracture-Related Diagenesis May Impact Conductivity. SPE J. 12 (3): 272–281. SPE-98236-PA. https://doi.org/10.2118/98236-PA.
Weaver, J. D. and Rickman, R. D. 2010. Productivity Impact from Geochemical Degradation of Hydraulic Fractures. Paper presented at the SPE Deep Gas Conference and Exhibition, Manama, Bahrain, 24–26 January. SPE-130641-MS. https://doi.org/10.2118/130641-MS.
Weaver, J. D., Rickman, R. D, and Luo, H. 2010. Fracture Conductivity Loss Caused by Geochemical Interactions between Man-Made Proppants and Formations. SPE J. 15 (1): 116–124. SPE-118174-PA. https://doi.org/10.2118/118174-PA.
Weaver, J. D., Rickman, R. D, Luo, H. et al. 2009. A Study of Proppant Formation Reactions. Paper presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands, Texas, USA, 20–22 April. SPE-121465-MS. https://doi.org/10.2118/121465-MS.
Weaver, J. D., Van Batenburg, D., and Nguyen, P. D. 2006. Sustaining Conductivity. Paper presented at the SPE International Symposium and Exhibition on Formation Damage Control, Lafayette, Louisiana, USA, 15–17 February. SPE-98236-MS. https://doi.org/10.2118/98236-MS.
Yasuhara, H., Elsworth, D., and Polak, A. 2003. A Mechanistic Model for Compaction of Granular Aggregates Moderated by Pressure Solution. J Geophys Res 108 (B11): 2530. https://doi.org/10.1029/2003JB002536.