Self-adaptive rock physics modeling method for tight sandstone reservoirs
ZHANG Jinqiang1,2,3, LIU Zhenfeng1,2,3, LIU Xiwu1,2,3, Han Lei1,2,3
1. SINOPEC Petroleum Exploration and Production Research Institute, Beijing 102206, China; 2. State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing 102206, China; 3. State Energy Center for Shale Oil Research and Development, SINOPEC, Beijing 102206, China
Abstract：In traditional rock physics modeling, the mi-neral components are known, and the equivalent elastic modulus of the rock matrix is solved with the Voigt-Reuss-Hill model. In the practice of rock physics modeling for tight sandstone reservoirs, accurate mineral component interpretation cannot be provided due to incomplete logging data. As a result, the accuracy of conventional rock physics modeling is affected. To tackle the problem, we propose a self-adaptive method for the rock physics modeling of tight sandstone reservoirs. The me-thod uses both the Gassmann equation and the criti-cal porosity model to estimate the elastic modulus of the rock matrix. According to the interpreted shale content curves, the upper and lower bounds of elastic moduli of shale and sandy components are estimated with the least square method and Voigt and Reuss models. A simulated annealing algorithm is employed to find the approximate elastic moduli of shale and sandy components. The values are fine-tuned according to the principle of constant P-wave modulus, and finally, the reasonable para-meters for rock physics modeling are obtained. Area M in the southern Ordos Basin is subject to rock physics modeling with this method and the results show that the elastic parameters of shale and tight sandstone can be well distinguished. Shale is cha-racterized by a high P-wave/S-wave velocity ratio and a low P-wave velocity. For sandstone, the P-wave/S-wave velocity ratio and the P-wave velocity decline as the porosity increases.
陈祖庆,杨鸿飞,王静波.基于叠前反演的致密砂岩含气储层识别技术研究[J].天然气技术与经济,2015,9(4):18-22.CHEN Zuqing,YANG Hongfei,WANG Jingbo.Identifying tight sandstone gas reservoir based on prestack inversion[J].Natural Gas Technology and Economy,2015,9(4):18-22.
[2]
张盟勃,史松群,潘玉.叠前反演技术在苏里格地区的应用[J].岩性油气藏,2007,19(4):91-94.ZHANG Mengbo,SHI Songqun,PAN Yu.Application of prestack inversion in Sulige area[J].Lithologic Reservoirs,2007,19(4):91-94.
[3]
蒋学峰.叠前反演技术在致密油甜点预测中的应用[J].石油化工高等学校学报,2018,31(3):76-80.JIANG Xuefeng.Application of pre-stack inversion technology in tight oil dessert prediction[J].Journal of Petrochemical Universities,2018,31(3):76-80.
[4]
王霞,张延庆,于志龙,等.叠前反演结合地质统计模拟预测薄储层[J].石油地球物理勘探,2011,45(5):744-748.WANG Xia,ZHANG Yanqing,YU Zhilong,et al.Thin reservoir prediction by prestack inversion combined with geostatistic simulation[J].Oil Geophysical Prospecting,2011,46(5):744-748.
[5]
汪关妹,张万福, 张宏伟等.致密砂岩气地震预测关键技术及效果[J].石油地球物理勘探,2020,55(增刊):72-79.WANG Guanmei,ZHANG Wanfu,ZHANG Hongwei,et al.Key technology and effect of prediction of tight sandstone gas based on seismic data[J].Oil Geophysical Prospecting,2020,55(S):72-79.
[6]
邹玮,张雷,姜勇,等.叠前反演在西湖凹陷A构造低渗气层边界识别中的应用[J].海洋石油,2015,35(2):46-49.ZOU Wei,ZHANG Lei,JIANG Yong,et al.Application of pre-stack inversion to identification of the boundary of low permeability gas reservoir in Xihu sag[J].Offshore Oil,2015,35(2):46-49.
[7]
刘建辉,明君,彭刚,等.叠前联合反演技术在渤海中深层储层预测中的应用[J].海洋地质前沿,2017,33(4):62-69.LIU Jianhui,MING Jun,PENG Gang,et al.Application of pre-stack joint inversion to mid-deep reservoir prediction in Bohai Bay[J].Marine Geology Letters,2017,33(4):62-69.
[8]
王斌,陈祥忠,陈娟,等.四川盆地侏罗系致密砂岩弹性特征及岩石物理建模[J].地球物理学报,2020,63(12):4528-4539.WANG Bin,CHEN Xiangzhong,CHEN Juan,et al.Elastic characteristics and petrophysical modeling of the Jurassic tight sandstone in Sichuan Basin[J].Chinese Journal of Geophysics,2020,63(12):4528-4539.
[9]
刘萱,谢占安,张国栋,等.南堡油田叠前反演技术与储层预测[J].天然气工业,2007,27(增刊A):439-442.LIU Xuan,XIE Zhan'an,ZHANG Guodong,et al.Prestack inversion and reservoirs prediction in Nanpu Oilfiled[J].Natural Gas Industry,2007,27(SA):439-442.
Nur A,Mavko G,Dvorkin J,et al.Critical porosity:the key to relating physical properties to porosity in rocks[C].SEG Technical Program Expanded Abstracts,1995,14:145-147.
[12]
Nur A,Marion D,Yin H.Wave velocities in sediments//Shear Waves in Marine Sediments[M].Kluwer Academic Publishers,Dordrecht,1991,131-140.
[13]
Krief M,Garat J,Stellingwerff J,et al.A petrophysical interpretation using the velocities of P and S waves (full-waveform sonic)[J].Log Analyst,1991,31(2):355-369.
[14]
Han D H,Nur A,Morgan D.Effects of porosity and clay content on wave velocities in sandstones[J].Geo-physics,1986,51(10):2093-2107.
[15]
Xu S Y,White R E.A new velocity model for clay-sand mixtures[J].Geophysical Prospecting,1995,43(1):91-118.
[16]
Xu S Y,White R E.A physical model for shear-wave velocity prediction[J].Geophysical Prospecting,1996,44(4):687-717.
[17]
刘浩杰.地震岩石物理研究综述[J].油气地球物理,2009,7(3):1-8.LIU Haojie.Summarization of seismic rock physics research[J].Petroleum Geophysics,2009,7(3):1-8.
[18]
马中高,张金强,蔡月晖,等.大牛地气田二叠系下石盒子组致密砂岩储层含气性识别因子研究[J].石油物探,2012,51(4):414-419.MA Zhonggao,ZHANG Jinqiang,CAI Yuehui,et al.Study on gas identification factor of tight sandstone reservoirs in Lower Shihezi formation from Daniudi Gasfield,Ordos Basin[J].Geophysical Prospecting for Petroleum,2012,51(4):414-419.
[19]
Raymer L L,Hunt E R,Gardner J S.An improved sonic transit time-to-porosity transform[C].21st Annual Logging Symposium of Society of Professitional Well Log Analysts,1980.
[20]
王震宇,刘俊州.岩石物理建模技术在致密砂岩储层预测中的应用——以鄂尔多斯盆地北部H区块为例[J].物探化探计算技术,2019,41(1):34-40 WANG Zhenyu,LIU Junzhou.Application of rock physics modeling in the prediction of tight sandstone reservoir:A case study of H block,Northern Erdos Basin[J].Computing Techniques for Geophysical and Geochemical Exploration,2019,41(1):34-40.
[21]
刘振峰,张金强,韩磊,等.鄂南长7段致密油地震流体识别技术应用实践[J],石油与天然气地质,2018,39(3):541-548.LIU Zhenfeng,ZHANG Jinqiang,HAN Lei,et al.Geophysical fluid recognition for tight oil in Chang 7 Member,south Ordos Basin[J].Oil & Gas Geology,2018,39(3):541-548.
