Well-Testing, In-Situ Fluid Sampling, and Stress Determination Methods for Unconventional Reservoirs
- Mehdi Azari (Halliburton) | Gibran Hashmi (Halliburton) | Farrukh Hamza (Halliburton) | Hoda Tahani (Halliburton)
- Document ID
- International Petroleum Technology Conference
- International Petroleum Technology Conference, 13-15 January, Dhahran, Kingdom of Saudi Arabia
- Publication Date
- Document Type
- Conference Paper
- 2020. International Petroleum Technology Conference
- Unconventional, First in-situ Fluid Sampling, and Stress Determination, Case studies, Well testing
- 19 in the last 30 days
- 98 since 2007
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Traditionally, production potential evaluation of newly drilled wells is determined with a drillstem test (DST) or a wireline formation tester to make decisions. Applying such techniques in unconventional formations is not always that easy owing to extremely tight formations that do not allow significant natural flow. Obtaining representative downhole fluid samples is also a major issue in unconventional wells. Unconventional gas condensate wells produce water for a long period after hydraulically fracturing the formation. Conventional fluid sampling acquires mostly water; surface sampling is not representative because the gas, condensate, and water flow rates change with slugs of fluid flowing to the surface.
To obtain undisturbed fluid samples, a new wireline formation tester technique was developed for unconventional formations. This method uses straddle packers to isolate a section in the wellbore to pump into the formation and create a fracture. Because these tight formations have limited invasion during drilling, they clean up faster during the pumping out period, with the created higher surface area increasing the flow rate. Formation mechanical properties, such as fracture initiation, instantaneous shut-in pressure (ISIP), fracture closure and opening pressures, and fracture extension pressure will all be obtained for this new microfracturing and fluid sampling technique.
Several well testing applications are discussed with corresponding analyses pertaining to unconventional gas and gas condensate wells in addition to some case studies for tight oil formations. The results provided valuable information to optimize production and evaluate reservoir potential. For example, a tight gas well was hydraulically fractured and did not produce after fracture stimulation because of water blockage; therefore, an injection/falloff test was recommended by injecting nitrogen into the formation and analyzing the falloff test. The well test analysis revealed that the early screenout caused an ineffective fracture length. The well was then refractured and has been producing since.
One of the issues with unconventional wells, particularly in tight gas wells, is that the wellbore storage lasts much longer than in standard wells. A downhole shut-in tool, or any test that minimizes the wellbore storage effects, can greatly reduce the duration of such tests and help improve the quality of the analysis results. A new extended diagnostic fracture injection test (DFIT) conducted with a downhole wireline operation that alleviated the problem of high wellbore storage and obtained pressurized pressure volume temperature (PVT) quality samples is also discussed. Because of controlled rates with an injection/falloff test in low-permeability wells, faster flow stabilization can be achieved, resulting in shorter wellbore-storage duration. This technique can obtain well and reservoir information in a shorter period of time than a conventional pressure-buildup test.
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Azari, M., Burleson, J., Soliman, M.Y.. 1996. Testing and Evaluation of Tubing-Conveyed Extreme Overbalanced Perforating. Presented at the SPE Eastern Regional Meeting, Columbus, Ohio, 23-25 October. SPE-37326-MS. https://doi.org/10.2118/37326-MS.
Azari, M., Guoynes, J., Soliman, M.Y.. 1997. Deliverability Enhancement and Well testing of Two Gas Storage Fields in Mt. Simon Formation—Case History. Presented at the SPE Eastern Regional Meeting, Lexington, Kentucky, 22-24 October. SPE-39208-MS. https://doi.org/10.2118/39208-MS.
Azari, M., Asadi, M., Schultz, R.. 1999. Finite Element and Neural Network Modeling of Extreme Overbalance Perforating. Presented at the SPE Mid-Continent Operations Symposium, Oklahoma City, Oklahoma, 28-31 March. SPE-52167-MS. https://doi.org/10.2118/52167-MS.
Azari, M., Hamza, F., Hadibeik, H., Ramakrishna, S., 2019. Well-Testing Challenges in Unconventional and Tight-Gas Formation Reservoirs. SPE Reservoir Engineering & Evaluation J. Preprint. https://dx.doi.org/10.2118/190025-PA.
Carlsen, M. L., Whitson, C. H., Alavian, A., ., 2019. Fluid Sampling in Tight Unconventionals. Presented at Annual Technical Conference and Exhibition, Calgary, Alberta, Canada, 30 September-2 October. https://dx.doi.org/10.2118/196056-MS.
Corredor, J., Hutto, E.Hamza, F.., 2019. Successful Downhole Microfracture, and PVT-Quality Formation Fluid Sampling from an Unconventional Reservoir. Presented at SPE/AAPG/EAGE Unconventional Resources Technology Conference, Denver, Colorado, USA, 22-24 July. https://dx.doi.org/10.15530/urtec-2019-418.
Curtis, M. E., Ambrose, R.J., Sondergeld, C.H.. 2011. Investigating the Microstructure of Gas Shales by FIB/SEM Tomography & STEM Imaging, http://ogs.ou.edu/docs/meetings/OGS-workshop-shales_moving_forward_2011-curtis.pdf (accecssed 28 10 2019).
Desroches, J. and Kurkjian, A.L., 1999. Applications of Wireline Stress Measurements, SPE Res Eval & Eng 2 (5): 451-461. SPE-58086-PA. https://dx.doi.org/10.2118/58086-PA.
Eaton, B.A., 1969. Fracture Gradient Prediction and Its Application in Oilfield Operations, J Pet Technol 21 (10): SPE-2163-MS. https://dx.doi.org/10.2118/2163-PA.
Hashmi, G.M., Kabir, C.S., and Hasan, A.R. 2015a. Estimating Reliable Gas Rate With Transient-Temperature Modeling for Interpreting Early-Time Cleanup Data During Transient Testing. J Pet Sci Eng 133: 285-295. https://doi.org/10.1016/j.petrol.2015.06.001.
Hashmi, G.M., Kabir, C.S., and Hasan, A.R. 2016. Design and Interpretation of Transient Tests at Well’s Inception. J Pet Sci Eng 145: 573-584. https://doi.org/10.1016/j.petrol.2016.06.035.
Jahabani, A. and Aguilera, R. 2008. Well Testing of Tight Gas Reservoirs. J Can Pet Technol 48 (10): 64-70. SPE-130066-PA. https://doi.org/10.2118/130066-PA.
Jin, M., Zhang, W., and Zhang, H. 2013. Integrated Well Test Strategy in Unconventional Tight Gas Reservoirs - Learning and Experiences From an Actual Field Project. Presented at the International Petroleum Technology Conference, Beijing, 26-28 March. IPTC-16950-Abstract. https://doi.org/10.2523/IPTC-16950-Abstract.
Kamal, M. M., Morsy, S., Suleen, F.. 2015. Determination of In Situ Reservoir Absolute Permeability Under Multiphase Flow Conditions Using Transient Well Testing. Presented at the SPE Annual Technical Conference and Exhibition, Houston, 28-30 September. SPE-175012-MS. https://doi.org/10.2118/175012-MS.
Kamal, M.M., Tian, C., and Suleen, F. 2016. Use of Transient Tests to Monitor Progress of Flooding in IOR / EOR Operations. Presented at the SPE Annual Technical Conference and Exhibition, Dubai, UAE, 26-28 September. SPE-181473-MS. https://doi.org/10.2118/181473-MS.
Kunze K.R. and Steiger R.P., 1992. Accurate In-Situ Stress Measurements During Drilling Operations. Presented at the 1992 SPE Annual Technical Conference and Exhibition, Washington D.C., October 4-7. SPE 24593-MS. https://doi.org/10.2118/24593-MS.
Lan, Y., Moghanloo, R.G., and Davudov, D. 2017. Pore Compressibility of Shale Formations. SPE J 22 (6): SPE-185059-PA. https://doi.org/10.2118/185059-PA.
Lee, W. J. 1987. Pressure-Transient Test Design in Tight Gas Formation. J Pet Technol 39 (10): 1185-1195. SPE-17088-PA. https://doi.org/10.2118/17088-PA.
Malik, M., Schwartz, K., Moelhoff, K.. 2014, Microfracturing in Tight Rocks: A Delaware Basin Case Study. Presented at the SPE Unconventional Resources Conference, The Woodlands, Texas, USA, 1-3 April. SPE-169009. https://dx.doi.org/10.2118/169009-MS.
Nolte, K. G. and Smith, M.B. 1981. Interpretation of Fracturing Pressures. JPT 33 (09). SPE-8297-MS https://dx.doi.org/10.2118/8297-PA.
Nagarajan, N.R. 2011. Reservoir Fluid Sampling of a Wide Spectrum of Fluid Types Under Different Conditions. Presented at the International Petroleum Technology Conference, Bangkok, Thailand, 15-17 November. IPTC-14360-MS. https://dx.doi.org/10.2523/IPTC-14360-MS.
Nguyen, D.H. and Cramer, D.D. 2013. Diagnostic Fracture Injection Testing Tactics in Unconventional Reservoirs. Presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, Texas, USA, 4-6 February. SPE-163863-MS. https://dx.doi.org/10.2118/163863-MS.
Pankaj, P. and Kumar, V. 2010. Well Testing in Tight Gas Reservoir: Today. Presented at the SPE Oil and Gas India Conference and Exhibition, Mumbai, India, 20-22 January. SPE-129032-MS. https://doi.org/10.2118/129032-MS.
Raaen, A.M. and Brudy, M. 2001. Pump-In/Flowback Tests Reduce the Estimate of Horizontal in-situ Stress Significantly. Presented at the Annual Technical Conference and Exhibition, New Orleans, Louisiana, Sep 30-3 Oct. SPE-71367-MS. https://dx.doi.org/10.2118/71367-MS.
Shahamat, M.S. and Aguilera, R. 2008. Pressure-Transient Test Design in Dual-Porosity Tight Gas Formations. Presented at the CIPC/SPE Gas Technology Symposium 2008 Joint Conference, Calgary, 16-19 June. SPE-115001-MS. https://doi.org/10.2118/115001-MS.
Shlyapobersky, L.. 1988. Field Determination of Fracturing Parameters for Overpressure Calibrated Design of Hydraulic Fracturing. Presented at the SPE Annual Technical Conference and Exhibition, Houston, 2-5 October. SPE-18195. https://dx.doi.org/10.2118/18195-MS.
Soliman, M.Y. 1986. Technique for Considering Fluid Compressibility and Temperature Changes in Mini-Frac Analysis. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana 5-8 October. SPE-15370-MS. https://doi.org/10.2118/15370-MS.
Soliman, M.Y. and Daneshy A.A. 1991. Determination of Fracture Volume and Closure Pressure From Pump-In/Flowback Tests. Presented at the SE Middle East Oil Show, Bahrain, 16-19 November. SPE-21400-MS. https://doi.org/10.2118/21400-MS.
Soliman, M.Y., Azari, M., and Hunt, J.L. 1996. Design and Analysis of Fractured Horizontal Wells in Gas Reservoirs. Presented at the SPE International Petroleum Conference and Exhibition of Mexico, Villahermosa, Mexico, 5-7 March. https://dx.doi.org/10.2118/35343-MS.
Soliman, M.Y., Hunt, J.L., and Azari, M. 1999. Fracturing Horizontal Wells in Gas Reservoirs. SPE Prod & Fac 14 (4): 277-283. SPE-59096-PA. https://doi.org/10.2118/59096-PA.
Soliman, M.Y., Azari, M., Ansah, J.. 2004. Design, Interpretation, and Assessment of Short-Term Pressure-Transient Tests. Presented at the SPE Annual Technical Conference and Exhibition, Houston, 26-29 September. SPE-90837-MS. https://doi.org/10.2118/90837-MS.
Soliman, M.Y., Craig, D.P., Bartko, K.M.. 2005. Post-Closure Analysis To Determine Formation Permeability, Reservoir Pressure, Residual Fracture Properties. Presented at the SPE Middle East Oil and Gas Show and Conference, Manama, Kingdom of Bahrain, 12- 15 March. SPE-93419-MS. https://doi.org/10.2118/93419-MS.
Soliman M.Y. and Gamadi, T.D. 2012. Testing Tight Gas and Unconventional Formations and Determination of Closure Pressure. Presented at the SPE/EAGE European Unconventional Resources Conference and Exhibition, Vienna, Austria, 20-22 March. SPE-150948-MS https://dx.doi.org/10.2118/150948-MS.