Citation: | YAO Jun, WANG Chunqi, HUANG Zhaoqin, et al. Digital core construction methods for high stress in deep and ultra-deep oil and gas reservoirs [J]. Petroleum Drilling Techniques,2024, 52(2):38-47. DOI: 10.11911/syztjs.2024039 |
Deep and ultra-deep oil and gas reservoirs buried at significant depths and subjected to ground stresses of 200 MPa, undergo notable changes in the pore microstructure of reservoir rocks. Digital core modeling serves as a crucial tool for pore-scale numerical simulations. However, current digital core reconstruction methods are based on scanning image reconstruction under normal temperature and pressure conditions and thus they fail to reflect the pore structure under high pressure conditions. Therefore, a digital core reconstruction method based on the discrete element method (DEM) was proposed by considering the effect of high stress. Initially, the watershed algorithm was employed to segment computed tomography (CT) images, and the contour database was established by the spherical harmonic analysis method. The Clump template library was established in PFC3D. Then, according to porosity and particle size distribution, the Clump in template library was used to build a discrete element model. After, the accuracy of the model was evaluated via calculations of two-point correlation and linear path correlation function curves. Next, the micromechanical parameters between particles were calibrated, enabling simulation of the digital core under varying stress conditions. Finally, the pore geometry topology of the digital core under different stresses was analyzed, and porosity and permeability were calculated. Bentheim sandstone was taken as an example to construct digital cores under different stresses.. The research results show that high stress leads to reduced pore and throat radius, elongated throats, diminished connectivity, and lower porosity and permeability. The results provide technical support for pore-scale simulations of deep and ultra-deep oil and gas reservoirs..
[1] |
贾承造,庞雄奇. 深层油气地质理论研究进展与主要发展方向[J]. 石油学报,2015,36(12):1457–1469.
JIA Chengzao, PANG Xiongqi. Research processes and main development directions of deep hydrocarbon geological theories[J]. Acta Petrolei Sinica., 2015, 36(12): 1457–1469.
|
[2] |
范家伟,袁野,李绍华,等. 塔里木盆地深层致密油藏地质工程一体化模拟技术[J]. 断块油气田,2022,29(2):194–198.
FAN Jiawei, YUAN Ye, LI Shaohua, et al. Geology-engineering integrated simulation technology of deep tight oil reservoir in Tarim Basin[J]. Fault-Block Oil & Gas Field, 2022, 29(2): 194–198.
|
[3] |
陈建勋. 深层高压碳酸盐岩气藏孔隙结构特征及衰竭开发规律[J]. 特种油气藏,2022,29(5):80–87.
CHEN Jianxun. Pore structure characteristics and natural depletion law of deep high-pressure carbonate gas reservoirs[J]. Special Oil & Gas Reservoirs, 2022, 29(5): 80–87.
|
[4] |
曾义金. 中国石化深层超深层油气井固井技术新进展与发展建议[J]. 石油钻探技术,2023,51(4):66–73.
ZENG Yijin. Novel advancements and development suggestions of cementing technologies for deep and ultra-deep wells of Sinopec[J]. Petroleum Drilling Techniques, 2023, 51(4): 66–73.
|
[5] |
王建云,韩涛,赵宽心,等. 塔深5井超深层钻井关键技术[J]. 石油钻探技术,2022,50(5):27–33.
WANG Jianyun, HAN Tao, ZHAO Kuanxin, et al. Key drilling technologies for the ultra-deep Well Tashen 5[J]. Petroleum Drilling Techniques, 2022, 50(5): 27–33.
|
[6] |
李虹,于海洋,杨海烽,等. 裂缝性非均质致密储层自适应应力敏感性研究[J]. 石油钻探技术,2022,50(3):99–105.
LI Hong, YU Haiyang, YANG Haifeng, et al. Adaptive stress sensitivity study of fractured heterogeneous tight reservoir[J]. Petroleum Drilling Techniques, 2022, 50(3): 99–105.
|
[7] |
孙强,孙志刚,张超. DLH油田低渗砂岩孔隙分形定量表征方法研究[J]. 西南石油大学学报(自然科学版),2023,45(1):105–116.
SUN Qiang, SUN Zhigang, ZHANG Chao. A study on fractal quantitative characterization method of low permeability sandstone pore in DLH Oilfield[J]. Joumal of Southwest Petroleum University (Seience & Technology Edition), 2023, 45(1): 105–116.
|
[8] |
姚军,黄朝琴,刘文政,等. 深层油气藏开发中的关键力学问题[J]. 中国科学:物理学 力学 天文学,2018,48(4):044701.
YAO Jun, HUANG Zhaoqin, LIU Wenzheng, et al. Key mechanical problems in the development of deep oil and gas reservoirs[J]. SCIENTIA SINICA Physica, Mechanica & Astronomica, 2018, 48(4): 044701.
|
[9] |
李荣强,高莹,杨永飞,等. 基于CT扫描的岩心压敏效应实验研究[J]. 石油钻探技术,2015,43(5):37–43.
LI, Rongqiang, GAO Ying, YANG Yongfei, et al. Experimental study on the pressure sensitive effects of cores based on CT scanning[J]. Petroleum Drilling Techniques, 2015, 43(5): 37–43.
|
[10] |
王晨晨,姚军,杨永飞,等. 基于CT扫描法构建数字岩心的分辨率选取研究[J]. 科学技术与工程,2013,13(4):1049–1052.
WANG Chenchen, YAO Jun, YANG Yongfei, et al. Study on resolution selection for digital rock construction with CT scanning method[J]. Science Technology and Engineering, 2013, 13(4): 1049–1052.
|
[11] |
刘洋,王春生,孙启冀,等. 低渗砂岩储层数字岩心构建及渗流模拟[J]. 断块油气田,2017,24(6):817–821.
LIU Yang, WANG Chunsheng, SUN Qiji, et al. Digital core construction and seepage simulation of low permeability sandstone reservoir[J]. Fault-Block Oil & Gas Field, 2017, 24(6): 817–821.
|
[12] |
姚军,宋文辉,李阳,等. 有机质孔隙对页岩气流动能力影响研究[J]. 中国科学:物理学 力学 天文学,2017,47(9):094702. doi: 10.1360/SSPMA2017-00040
YAO Jun, SONG Wenhui, LI Yang, et al. Study on the influence of organic pores on shale gas flow ability[J]. Scientia Sinaca: Physica, Mechanica & Astronomica, 2017, 47(9): 094702. doi: 10.1360/SSPMA2017-00040
|
[13] |
ØREN P E, BAKKE S. Process based reconstruction of sandstones and prediction of transport properties[J]. Transport in Porous Media, 2002, 46(2): 311–343.
|
[14] |
姚军,赵秀才,衣艳静,等. 数字岩心技术现状及展望[J]. 油气地质与采收率,2005,12(6):52–54.
YAO Jun, ZHAO Xiucai, YI Yanjing, et al. The current situation and prospect on digital core technology[J]. Petroleum Geology and Recovery Efficiency, 2005, 12(6): 52–54.
|
[15] |
YANG Yongfei, LIU Fugui, YAO Jun, et al. Multi-scale reconstruction of porous media from low-resolution core images using conditional generative adversarial networks[J]. Journal of Natural Gas Science and Engineering, 2022, 99: 104411. doi: 10.1016/j.jngse.2022.104411
|
[16] |
杨永飞,刘夫贵,姚军,等. 基于生成对抗网络的页岩三维数字岩芯构建[J]. 西南石油大学学报(自然科学版),2021,43(5):73–83.
YANG Yongfei, LIU Fugui, YAO Jun, et al. Reconstruction of 3D shale digital rock based on generative adversarial network[J]. Journal of Southwest Petroleum University (Science & Technology Edition), 2021, 43(5): 73–83.
|
[17] |
陈林,黎棚武,张绍俊,等. 基于机器学习的岩芯渗透率及裂缝开度预测[J]. 西南石油大学学报(自然科学版),2023,45(4):155–163.
CHEN Lin, LI Pengwu, ZHANG Shaojun, et al. Prediction method of core permeability and fracture aperture based on machine learning[J]. Journal of Southwest Petroleum University (Science & Technology Edition), 2023, 45(4): 155–163.
|
[18] |
SAENGER E H, LEBEDEV M, URIBE D, et al. Analysis of high-resolution X-ray computed tomography images of Bentheim sandstone under elevated confining pressures[J]. Geophysical Prospecting, 2016, 64(4): 848–859.
|
[19] |
ZHU Linqi, ZHANG Chong, ZHANG Chaomo, et al. Challenges and prospects of digital core-reconstruction researc[J]. Geofluids, 2019, 2019: 7814180.
|
[20] |
FAN Ming, MCCLURE J, HAN Yanhui, et al. Interaction between proppant compaction and single-/multiphase flows in a hydraulic fracture[J]. SPE Journal, 2018, 23(4): 1290–1303. doi: 10.2118/189985-PA
|
[21] |
CUNDALL P A, STRACK O D L. A discrete numerical model for granular assemblies[J]. Géotechnique, 1979, 29(1): 47–65. doi: 10.1680/geot.1979.29.1.47
|
[22] |
ZHENG Junxing, HRYCIW R D. Segmentation of contacting soil particles in images by modified watershed analysis[J]. Computers and Geotechnics, 2016, 73: 142–152. doi: 10.1016/j.compgeo.2015.11.025
|
[23] |
ZHAO Shiwei, ZHAO Jidong. A poly-superellipsoid-based approach on particle morphology for DEM modeling of granular media[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 2019, 43(13): 2147–2169.
|
[24] |
ANDRADE J E, LIM K W, AVILA C F, et al. Granular element method for computational particle mechanics[J]. Computer Methods in Applied Mechanics and Engineering, 2012, 241(): 262–274.
|
[25] |
BOWMAN E T, SOGA K, DRUMMOND W. Particle shape characterisation using Fourier descriptor analysis[J]. Geotechnique, 2001, 51(6): 545–554.
|
[26] |
GARBOCZI E J. Three-dimensional mathematical analysis of particle shape using X-ray tomography and spherical harmonics: application to aggregates used in concrete[J]. Cement and concrete research, 2002, 32(10): 1621–1638.
|
[27] |
WEI Deheng, WANG Jianfeng, ZHAO Budi. A simple method for particle shape generation with spherical harmonics[J]. Powder Technology, 2018, 330: 284–291. doi: 10.1016/j.powtec.2018.02.006
|
[28] |
LI Zechuang, LIU Zhibin. Influence of particle shape on the macroscopic and mesolevel mechanical properties of slip zone soil based on 3D scanning and 3D DEM[J]. Advances in Materials Science and Engineering, 2021, 2021: 1–14.
|
[29] |
LAI Zhengshou, CHEN Qiushi. Characterization and discrete element simulation of grading and shape-dependent behavior of JSC-1A Martian regolith simulant[J]. Granular Matter, 2017, 19(4): 69.
|
[30] |
KHALEGHI K, TALMAN S, SHOKRI A R, et al. A coupled pore-scale modelling approach to capture macro-scale stress-dependent permeability of rocks[R]. URTEC 198264, 2019.
|
[31] |
KAWAMOTO R, ANDÒ E, VIGGIANI G, et al. Level set discrete element method for three-dimensional computations with triaxial case study[J]. Journal of the Mechanics and Physics of Solids, 2016, 91: 1–13.
|
[32] |
KLEIN E, BAUD P, REUSCHLÉ T et al. Mechanical behaviour and failure mode of bentheim sandstone under triaxial compression[J]. Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy, 2001, 26(1/2): 21–25.
|
[33] |
YANG Yongfei, ZHANG Wenjie, GAO Ying, et al. Influence of stress sensitivity on microscopic pore structure and fluid flow in porous media[J]. Journal of Natural Gas Science and Engineering, 2016, 36(part A): 20–31.
|
[34] |
LU Jun, YIN Guangzhi, DENG Bozhi, et al. Permeability characteristics of layered composite coal-rock under true triaxial stress conditions[J]. Journal of Natural Gas Science and Engineering, 2019, 66: 60–76. doi: 10.1016/j.jngse.2019.03.023
|