Abstract
The lower Paleozoic Majiagou Formation reservoir, located in the southern area of the Ordos Basin, is a typical tight carbonate gas reservoir with an average burial depth of about 3000 m, a formation pressure coefficient of 0.8, a porosity of 3.16%, and a permeability of 0.13 mD. The gas production was generally low after hydraulic fracturing at early-stage development, and the proportion of wells with industrial gas capacity is less than 25%. During the fluid discharge phase, the flowback rate was generally low (less than 30%), the bottom hole flow pressure was small (less than 7 MPa), and the flowback pressure difference was large (more than 15 MPa). Because the initial water saturation of tight reservoirs is usually less than the irreducible water saturation, the retention of a large amount of undischarged fracturing fluid in the formation causes the increase of water saturation in the near-well area, resulting in damage to gas permeability. The ‘water trapping effect’ is serious in the near-well area, and no liquid was produced during the later stage of drainage, making it impossible to obtain the true production capacity of the reservoir. In order to improve the effectiveness of fracturing, a soak test after hydraulic fracturing was carried out in the tight carbonate gas reservoir. After 50 days of soaking and pressure diffusion, the fracturing fluid in the near-wellbore area was dispersed to the deep formation by capillary force. As the diffusion area increased, the water saturation in the near-wellbore area was reduced, and the gas permeability was effectively restored. The daily gas production increased from 4,678 m3 to 8,424 m3 after soaking under pressure. The successful trial of this technology has a significant reference for improving the effectiveness of hydraulic fracturing and understanding the true production capacity of tight gas reservoirs .
Copyright 2023, IFEDC Organizing Committee.
This paper was prepared for presentation at the 2023 International Field Exploration and Development Conference in Wuhan, China, 20–22 September 2023.
This paper was selected for presentation by the IFEDC Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper, as presented, have not been reviewed by the IFEDC Technical Team and are subject to correction by the author(s). The material does not necessarily reflect any position of the IFEDC Technical Committee its members. Papers pre-sented at the Conference are subject to publication review by Professional Team of IFEDC Technical Committee. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of IFEDC Organizing Committee is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of IFEDC. Contact email: pa-per@ifedc.org.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Holditch, S.A.: Tight gas sands. J. Pet. Technol. JPT 58(6), 86–93 (2006)
Alkouh, A., McKetta, S., Wattenbarger, R.A.: Estimation of effective- fracture volume using water-flowback and production data for shale-gas wells. J. Can. Pet. Technol. 53(05), 290–303 (2014)
Alotaibi, M.B., Nasralla, R.A., Nasr-El-Din, H.A.: Wettability studies using low salinity water in sandstone reservoirs. SPE Res. Eval. Eng. 14(06), 713–725 (2011). SPE-149942-PA
Bahrami, H., et al.: Effect of water blocking damage on flow efficiency and productivity in tight gas reservoirs. In: Presented at the SPE Production and Operations Symposium, Oklahoma City, Oklahoma, USA, 27–29 March 2011. SPE-142283-MS
Bahrami, H., Rezaee, R., Clennell, B.: Water blocking damage in hydraulically fractured tight sand gas reservoirs: an example from Perth basin, western Australia. J. Petrol. Sci. Eng. 88–89(1), 100–106 (2012)
Lei, Q., et al.: Progress and development directions of shale oil reservoir stimulation technology of China national petroleum corporation. Pet. Explor. Dev. 48(5), 1035–1042 (2021)
Wang, F., et al.: A pressure drop model of post-fracturing shut-in considering the effect of fracturing-fluid imbibition and oil replacement. Pet. Expl. Dev. 48(6), 1250–1257 (2021)
Jeon, J., et al.: Fracturing carbonate reservoirs: Acidising fracturing or fracturing with proppants? Day 2 Thu, August 25, 2016. Beijing, China. SPE, 2016: D022S010R042
Cui, M., et al.: A case study: the first hydraulically fractured well in carbonate reservoirs in Iraq. Day 2 Wed, October 24, 2018. Brisbane, Australia: SPE, 2018: D021S014R003
Azad, M., et al.: Case study of hydraulic fracturing in an offshore carbonate oil reservoir. Pet. Res. 7(4), 419–429 (2022)
Earlougher, R.C.: Advances in well test analysis, vol. 5. New York: Henry L. Doherty Memorial Fund of AIME (1977)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2024 The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
About this paper
Cite this paper
Zhang, B., Xu, Y., Wang, K., Wan, Xh., Jiang, Wx., Wu, Yr. (2024). Technology of Soak After Hydraulic Fracturing to Increase Production in Tight Carbonate Gas Reservoirs. In: Lin, J. (eds) Proceedings of the International Field Exploration and Development Conference 2023. IFEDC 2023. Springer Series in Geomechanics and Geoengineering. Springer, Singapore. https://doi.org/10.1007/978-981-97-0260-2_122
Download citation
DOI: https://doi.org/10.1007/978-981-97-0260-2_122
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-97-0259-6
Online ISBN: 978-981-97-0260-2
eBook Packages: EngineeringEngineering (R0)