基于Gassmann方程的流体替换
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摘要
随着油气勘探开发的不断深入,油气储集体越来越复杂,因而勘探重点由原来的构造油气藏向岩性油气藏、隐蔽型油气藏转移。当今地震勘探技术成为了发现新油气资源的重要手段,岩石物理技术则成为通过了解地下岩石和流体声波响应的最有效途径,而地震岩石物理技术有效地将地震勘探与岩石物理研究紧密地结合起来,定量地描述了岩石和油气间的关系。地震技术是研究隐蔽油气藏的关键技术。岩石物理是地震信号与储层性质之间的桥梁,它可以帮助我们更好的理解岩石和流体性质的地震响应。流体替代分析是岩石物理分析的重要部分,它是流体识别和储层定量研究的工具之一,在AVO分析中起了重要的作用。
本文首先介绍了地震波在含流体介质中的传播理论,在“有效介质理论模型”部分,重点分析了空间平均模型、自适应(自洽)模型和散射理论模型的假设前提与应用条件,论述了双相、多相介质的自适应近似和不同形状包裹体的几何描述以及裂隙介质模型的不同数学表述。在地震岩石物理学的核心内容“多孔介质的流体机制模型”部分,重点论述了Gassmann方程、Biot理论和BISQ模型等多孔介质模型所基于的流体流动机制,对比分析了不同模型的衰减与频散机理。在“速度影响因素分析”部分,集中论述了岩石密度、孔隙度、泥质含量、流体饱和度等因素对地震波速度的影响作用,相关的通用性经验关系模型,以及纵、横波速度关系和岩石各向异性研究等地震岩石物理学实验研究的重要成果。本文在研究区采用地震岩石物理分析的重要技术手段——流体替换。
Gassmann方程是岩石弹性物理研究的重要理论工具,文中利用Gassmann方程推演了流体替换的详细计算过程,得出了等效的速度和密度值,之后通过给出的速度、密度模型图,分别替换了当孔隙度为5%时的两层灰岩的情况。同时分析对比了替换含气/含水的不同孔隙度在替换后替换层段反射振幅变化的不同情况,此时孔隙度越小,振幅越强,替换后的效果就越好。
在实际的储层应用中,本文就研究区内仅ma2井钻遇目的层,而且ma2钻遇的储层物性较差,没有取得良好的油气显示。因此,开展对ma2井的流体替换的研究,有助于外推得到储层物性好的地震响应特征。根据计算所得速度模型,进行流体替换的正演模拟,分析了在不同孔隙度(5%、8%、10%)时的该储层的地震反射特征。最后由实际资料得出随着孔隙度的越大,采用Gassmann方程计算得到的等效速度就越低,其与围岩(灰岩)的物性差异就越大,流体替换后层段的反射振幅也就会越强。最后由实际资料得出随着孔隙度的增大,储层波阻抗降低,与围岩的波阻抗差增大,流体替换后层段的反射振幅也就会逐渐增强。这与实际情况相符,为流体识别提供了依据。
With the oil and gas exploration and the deepening of increasingly complex oil and gas reservoirs, thus the focus from exploration of the structural reservoir to the lithologic reservoir, cover transfer of oil and gas reservoir type. Present-day seismic exploration technology to discover new oil and gas has become an important means of resources, rock physics technology has become the underground through the rock and fluid understanding of sound waves in response to the most effective way, while the seismic rock physics technology effectively and seismic rock physics research combine closely quantitatively describe the rocks and the relationship between oil and gas. Seismic data analysis is one of the key technologies for characterizing subtle reservoirs and monitoring subsurface pore fluids. Fundamental rock physics can help us understand seismic response of rocks and fluid properties. Fluid substitution is an important part of rock physics and is a tool of identifying fluid and quantifying formation, and it also plays an important role in AVO analysis.
Propagation theory of seismic waves in fluid medium has been introduced in the paper firstly. In“Effective-Medium Model”section, the stress was analyzed the assumption and limitations for volume average model, self-consistent model, and scattering theoretic model, expound the self-consistent approximations to two-phase media, heterogeneous media, the geometry description to different shape inclusion, and the mathematic expression to a cracked media. In“Mechanism of Acoustic Propagation in a Fluid Saturated Porous Media”section, the kernel substance of seismic rock physics, emphatically expound Gassmann’s relations, Biot’s theory and BISQ (Biot-squirt) model, and what based on fluid flow mechanism. Comparative analysis attenuation and dispersion mechanism expressed in distinct model. In“Analyzing for Velocity Effects”, many empirical relations was expounded in seismic wave velocity effected from rock density, porosity, clay content, saturation and correlated common empirical relation models, along with V P- V S relations and rock anisotropy research in laboratory.
The significant technique in seismic rock physics analysis-fluid substation. Gassmann equation is an important theoretical tool for researching on rocks elasticity. Deduce the detailed calculation process of fluid substitution by use of Gassmann equation in the paper, and come to the equivalent value of the speed and density. Finally give out the density and velocity model diagram, and replace respectively a two-layer limestone when the porosity of 5% of the cases. At the same time, analysis and comparison of the replacement gas/water content of different porosity in the replacement of the replacement layer after reflection amplitude changes in different situations. At this point the smaller the porosity, the amplitude of the more intense the effect replaced the better.
Reservoir in the actual applications, this article on the study area only when the purpose of drilling wells ma2 layer, and the once-ma2 drilling poor reservoir properties, there is no good for oil and gas show. Therefore, the carrying out of the wells ma2 study fluid replacement helps to extrapolate good reservoir properties have been in response to the characteristics of the earthquake. In accordance with the calculated velocity model for fluid replacement forward modeling, analysis of the different porosity(5%、8%、10%) of the reservoir at the time of the seismic reflection characteristics. Finally, with the actual information to draw the greater the porosity, Gassmann equation calculated using the equivalent speed of the lower, with the surrounding rock (limestone) of the material the greater the difference, after the layer of fluid to replace the reflection amplitude also will be stronger. In the end the actual information to draw with the increasing porosity of the reservoir to lower wave impedance and the surrounding poor increased, after the layer of fluid to replace the reflection amplitude will also gradually. This is in line with the actual situation, in order to provide a basis for fluid identification.
本文首先介绍了地震波在含流体介质中的传播理论,在“有效介质理论模型”部分,重点分析了空间平均模型、自适应(自洽)模型和散射理论模型的假设前提与应用条件,论述了双相、多相介质的自适应近似和不同形状包裹体的几何描述以及裂隙介质模型的不同数学表述。在地震岩石物理学的核心内容“多孔介质的流体机制模型”部分,重点论述了Gassmann方程、Biot理论和BISQ模型等多孔介质模型所基于的流体流动机制,对比分析了不同模型的衰减与频散机理。在“速度影响因素分析”部分,集中论述了岩石密度、孔隙度、泥质含量、流体饱和度等因素对地震波速度的影响作用,相关的通用性经验关系模型,以及纵、横波速度关系和岩石各向异性研究等地震岩石物理学实验研究的重要成果。本文在研究区采用地震岩石物理分析的重要技术手段——流体替换。
Gassmann方程是岩石弹性物理研究的重要理论工具,文中利用Gassmann方程推演了流体替换的详细计算过程,得出了等效的速度和密度值,之后通过给出的速度、密度模型图,分别替换了当孔隙度为5%时的两层灰岩的情况。同时分析对比了替换含气/含水的不同孔隙度在替换后替换层段反射振幅变化的不同情况,此时孔隙度越小,振幅越强,替换后的效果就越好。
在实际的储层应用中,本文就研究区内仅ma2井钻遇目的层,而且ma2钻遇的储层物性较差,没有取得良好的油气显示。因此,开展对ma2井的流体替换的研究,有助于外推得到储层物性好的地震响应特征。根据计算所得速度模型,进行流体替换的正演模拟,分析了在不同孔隙度(5%、8%、10%)时的该储层的地震反射特征。最后由实际资料得出随着孔隙度的越大,采用Gassmann方程计算得到的等效速度就越低,其与围岩(灰岩)的物性差异就越大,流体替换后层段的反射振幅也就会越强。最后由实际资料得出随着孔隙度的增大,储层波阻抗降低,与围岩的波阻抗差增大,流体替换后层段的反射振幅也就会逐渐增强。这与实际情况相符,为流体识别提供了依据。
With the oil and gas exploration and the deepening of increasingly complex oil and gas reservoirs, thus the focus from exploration of the structural reservoir to the lithologic reservoir, cover transfer of oil and gas reservoir type. Present-day seismic exploration technology to discover new oil and gas has become an important means of resources, rock physics technology has become the underground through the rock and fluid understanding of sound waves in response to the most effective way, while the seismic rock physics technology effectively and seismic rock physics research combine closely quantitatively describe the rocks and the relationship between oil and gas. Seismic data analysis is one of the key technologies for characterizing subtle reservoirs and monitoring subsurface pore fluids. Fundamental rock physics can help us understand seismic response of rocks and fluid properties. Fluid substitution is an important part of rock physics and is a tool of identifying fluid and quantifying formation, and it also plays an important role in AVO analysis.
Propagation theory of seismic waves in fluid medium has been introduced in the paper firstly. In“Effective-Medium Model”section, the stress was analyzed the assumption and limitations for volume average model, self-consistent model, and scattering theoretic model, expound the self-consistent approximations to two-phase media, heterogeneous media, the geometry description to different shape inclusion, and the mathematic expression to a cracked media. In“Mechanism of Acoustic Propagation in a Fluid Saturated Porous Media”section, the kernel substance of seismic rock physics, emphatically expound Gassmann’s relations, Biot’s theory and BISQ (Biot-squirt) model, and what based on fluid flow mechanism. Comparative analysis attenuation and dispersion mechanism expressed in distinct model. In“Analyzing for Velocity Effects”, many empirical relations was expounded in seismic wave velocity effected from rock density, porosity, clay content, saturation and correlated common empirical relation models, along with V P- V S relations and rock anisotropy research in laboratory.
The significant technique in seismic rock physics analysis-fluid substation. Gassmann equation is an important theoretical tool for researching on rocks elasticity. Deduce the detailed calculation process of fluid substitution by use of Gassmann equation in the paper, and come to the equivalent value of the speed and density. Finally give out the density and velocity model diagram, and replace respectively a two-layer limestone when the porosity of 5% of the cases. At the same time, analysis and comparison of the replacement gas/water content of different porosity in the replacement of the replacement layer after reflection amplitude changes in different situations. At this point the smaller the porosity, the amplitude of the more intense the effect replaced the better.
Reservoir in the actual applications, this article on the study area only when the purpose of drilling wells ma2 layer, and the once-ma2 drilling poor reservoir properties, there is no good for oil and gas show. Therefore, the carrying out of the wells ma2 study fluid replacement helps to extrapolate good reservoir properties have been in response to the characteristics of the earthquake. In accordance with the calculated velocity model for fluid replacement forward modeling, analysis of the different porosity(5%、8%、10%) of the reservoir at the time of the seismic reflection characteristics. Finally, with the actual information to draw the greater the porosity, Gassmann equation calculated using the equivalent speed of the lower, with the surrounding rock (limestone) of the material the greater the difference, after the layer of fluid to replace the reflection amplitude also will be stronger. In the end the actual information to draw with the increasing porosity of the reservoir to lower wave impedance and the surrounding poor increased, after the layer of fluid to replace the reflection amplitude will also gradually. This is in line with the actual situation, in order to provide a basis for fluid identification.
引文
[1] Gassmann F.Elastic waves through a Peaking of spheres [J].Geophysics, 1951, 16:673-682
[2] Biot M.A.Theory of propagation of elastic waves in a fluid saturated porous solidⅠ:Low frequency range, andⅡ: Higher-frequency range [J]. Journal of the Acoustical Society of America, 1956, 28:168一196
[3] Wyllie M.R.J.Gregory A.R.,Gardner L.W.,Elastic wave velocities in heterogeneous and porous media [J].Geophysics, 1956, 21:41一70
[4] Biot M.A. and Willis D.G,The elastic coefficients of the theory of consolidation [J]. Journal of Appl.Mech, 1957, 24(3):594一601
[5] Gardner G.H.F. Gardner L.W. Gregory A.R., Formation velocity and density—the diagnostic basics for stratigraphic traps [J]. Geophysics, 1974, 39(6):770-780
[6] Brown R.and Korringa J. On the dependence of the elastic properties of a porous rock on the compressibility of the pore fluid [J]. Geophysics, 1975, 40(3):608-616
[7] G Mavko, T Mukerji. Seismic pore space compressibility and Gassmann’s relation, 1995, Geophysics, 60(6):1743-1749
[8] Castagna J P, Batzle M L, Eastwood R L., Relationships between compressional-wave and shear-wave velocities in clastic silicate rocks [J]. Geophysics, 1985, 50(4):571-581
[9] Goodway W, Chen T, Downton J. Improved AVO fluid detection and lithology discrimination using Lame petrophysical parameters from P and S inversion [J]. Expanded Abstracts of 68th Annual International SEG Meeting, 1997, 183-186
[10] Han D., H. Nur A., Morgan D., Effects of porosity and clay content on wave velocities in sandstones [J]. Geophysics, 1986, 51(11):2093-2107
[11] G Mavko, C Chan, T Mukerji Fluid substitution: Estimating changes in V p without knowing Vs , 1995, Geophysics, 60(6):1750-1755
[12] Connolly P., Elastic impedance [J], The Leading Edge, 1999, 18:438-452.
[13] Wang Z., Fundamentals of seismic rock physics [J]. Geophysics, 2001, 66(2):398-412
[14] B.H.Russell, K.Hedlin Fluid-property discrimination with AVO: A Biot-Gassmann prospective [J]. 2003 Geophysics, 68(1):29-39
[15] Dillon L, Schwedersky G.Guilherme V,et al.A multiscale DHI elastic attributes evaluation [J]. The Leading Edge, 2003, 22(10):1024-1029
[16] B.Gurevich and J.Galvin Fluid substitution, dispersion, and attenuation in fractured and porous reservoirs—insights from new rock physics models [J], 2007, The Leading EDGE, 26(9):1162-1168
[17]贺振华主编:反射地震资料的便宜与反演方法[M],重庆大学出版社,1999
[18]何樵登:地震勘探原理与方法[M]北京:地质出版社,1986
[19]陆基孟:地震勘探原理[M]东营:石油大学出版社,1993
[20]陈颙,黄庭芳:岩石物理学[M].北京大学出版社,2001.
[21]马中高,管路平,贺振华,徐雷鸣:利用模型正演优化地震属性进行储层预测[J],石油学报,2003,24(6):35-39.
[22]王西文:岩性油气藏的储层预测及评价技术研究[J].石油物探,2004,43(6):511-517
[23]刘洋:利用地震资料估算孔隙度和饱和度的一种新方法[J].石油学报,2005,26(2):61—64
[24]金龙,陈小宏,姜香云:利用地震资料定量反演孔隙度和饱和度的新方法[J].石油学报,2006,27(4):63—66
[25]刘国萍,陈小宏,李景叶:弹性波阻抗在时移地震中的应用分析[J].地球物理学进展,2006,21(2):559—563.
[26]王贤,杨永生等:地震正演模型在预测薄储层中的应用[J].新疆地质,2007,25(4):432-434.
[27]李景叶:基于地震资料的储层流体识别[J],石油学报,2008,29(2):235-238.
[28]张秀萍:利用地震正演和属性分析技术预测生物灰岩储层分析[J],石油天然气学报,2008,30(2):88-90.
[29]贺振华,李正文:勘查技术工程学[M].地质出版社,2001.
[30]邹文:基于地震资料的流体识别技术研究[D]成都理工大学博士论文,2008年
[31]殷八斤:AVO技术的理论与实践[M].北京:石油工业出版社,l995.
[32]王炳章:地震岩石物理学及其应用研究[D].成都理工大学博士论文,2008年
[33]马中高:碎屑岩地震岩石物理学特征研究[D],成都理工大学博士论文,2008年
[34]杨东全:岩石物理性质和钻柱涡动机理研究[D].北京:清华大学,1999年
[35]朱广生,陈传仁,桂志先:勘探地震学教程[M].武汉大学出版社,2005.
[36]葛瑞·马沃可,塔潘·木克基等:岩石物理手册-孔隙介质中地震分析工具[M].安徽:中国科学技术大学出版社,2008
[37]郝晓红,王闯,谢春雨:流体替代技术及应用分析[J].海洋石油,2008,9(3)1-5
[38]甘利灯:四维地震技术及其在水驱油藏监测中的应用[D],北京:中国地质大学,2002
[39]王荣东:多相介质地震波场模拟与AVO属性分析[D],北京,中国地质大学,2007
[40]武文来,印兴耀:岩石物理参数与地球物理特征关系研究—以QHD326油田为例[J],石油物探,2008,5(3):235-243
[41]胡作维等:储层砂岩波阻抗及拉梅常数实验研究[J].地球科学与环境学报,2006,28(4),54-57.
[42]王家映编著:地球物理反演理论[M].中国地质大学出版社,1998.
[43]李维新,史謌,王红,姚振兴:岩石物理弹性参数规律研究[J].地球物理学进展,2007,22(5),1380-1385.
[44]贺振华,黄德济等:复杂油气藏地震波场特征方法理论及应用[M],四川科学技术出版社,1999
[45]朱广生:地震资料储层预测方法[M].石油大学出版社,1995
[46]万明浩,秦顺亭等:岩石物理性质及其在石油勘探中的应用[M],地质出版社,1994
[47]黄凯,徐群洲,杨晓海等:纵、横波在岩石中的传播速度比及弹性模量与岩石所含流体的关系[J].新疆石油地质,1998,19(5):369-371.
[48]李录明,李正文著:地震勘探原理、方法及解释[M].地质出版社,2007.
[49]石玉梅等:弹性参数在岩性油气藏勘探中的应用_以苏里格气田为例[J].中国石油勘探,2006,11(4):80-84.
[50] Fred J. Hilterman著,孙夕平,赵良武等译:地震振幅解释[M].石油工业出版社,2006
[51]贺振华,黄德济:缝洞储层的地震检测和预测[J],勘探地球物理进展,2003,26(2):79-83.
[52]陈信平,刘素红:浅谈Gassmann方程[J],中国海上油气(地质),1996,10(2):122-127.
[2] Biot M.A.Theory of propagation of elastic waves in a fluid saturated porous solidⅠ:Low frequency range, andⅡ: Higher-frequency range [J]. Journal of the Acoustical Society of America, 1956, 28:168一196
[3] Wyllie M.R.J.Gregory A.R.,Gardner L.W.,Elastic wave velocities in heterogeneous and porous media [J].Geophysics, 1956, 21:41一70
[4] Biot M.A. and Willis D.G,The elastic coefficients of the theory of consolidation [J]. Journal of Appl.Mech, 1957, 24(3):594一601
[5] Gardner G.H.F. Gardner L.W. Gregory A.R., Formation velocity and density—the diagnostic basics for stratigraphic traps [J]. Geophysics, 1974, 39(6):770-780
[6] Brown R.and Korringa J. On the dependence of the elastic properties of a porous rock on the compressibility of the pore fluid [J]. Geophysics, 1975, 40(3):608-616
[7] G Mavko, T Mukerji. Seismic pore space compressibility and Gassmann’s relation, 1995, Geophysics, 60(6):1743-1749
[8] Castagna J P, Batzle M L, Eastwood R L., Relationships between compressional-wave and shear-wave velocities in clastic silicate rocks [J]. Geophysics, 1985, 50(4):571-581
[9] Goodway W, Chen T, Downton J. Improved AVO fluid detection and lithology discrimination using Lame petrophysical parameters from P and S inversion [J]. Expanded Abstracts of 68th Annual International SEG Meeting, 1997, 183-186
[10] Han D., H. Nur A., Morgan D., Effects of porosity and clay content on wave velocities in sandstones [J]. Geophysics, 1986, 51(11):2093-2107
[11] G Mavko, C Chan, T Mukerji Fluid substitution: Estimating changes in V p without knowing Vs , 1995, Geophysics, 60(6):1750-1755
[12] Connolly P., Elastic impedance [J], The Leading Edge, 1999, 18:438-452.
[13] Wang Z., Fundamentals of seismic rock physics [J]. Geophysics, 2001, 66(2):398-412
[14] B.H.Russell, K.Hedlin Fluid-property discrimination with AVO: A Biot-Gassmann prospective [J]. 2003 Geophysics, 68(1):29-39
[15] Dillon L, Schwedersky G.Guilherme V,et al.A multiscale DHI elastic attributes evaluation [J]. The Leading Edge, 2003, 22(10):1024-1029
[16] B.Gurevich and J.Galvin Fluid substitution, dispersion, and attenuation in fractured and porous reservoirs—insights from new rock physics models [J], 2007, The Leading EDGE, 26(9):1162-1168
[17]贺振华主编:反射地震资料的便宜与反演方法[M],重庆大学出版社,1999
[18]何樵登:地震勘探原理与方法[M]北京:地质出版社,1986
[19]陆基孟:地震勘探原理[M]东营:石油大学出版社,1993
[20]陈颙,黄庭芳:岩石物理学[M].北京大学出版社,2001.
[21]马中高,管路平,贺振华,徐雷鸣:利用模型正演优化地震属性进行储层预测[J],石油学报,2003,24(6):35-39.
[22]王西文:岩性油气藏的储层预测及评价技术研究[J].石油物探,2004,43(6):511-517
[23]刘洋:利用地震资料估算孔隙度和饱和度的一种新方法[J].石油学报,2005,26(2):61—64
[24]金龙,陈小宏,姜香云:利用地震资料定量反演孔隙度和饱和度的新方法[J].石油学报,2006,27(4):63—66
[25]刘国萍,陈小宏,李景叶:弹性波阻抗在时移地震中的应用分析[J].地球物理学进展,2006,21(2):559—563.
[26]王贤,杨永生等:地震正演模型在预测薄储层中的应用[J].新疆地质,2007,25(4):432-434.
[27]李景叶:基于地震资料的储层流体识别[J],石油学报,2008,29(2):235-238.
[28]张秀萍:利用地震正演和属性分析技术预测生物灰岩储层分析[J],石油天然气学报,2008,30(2):88-90.
[29]贺振华,李正文:勘查技术工程学[M].地质出版社,2001.
[30]邹文:基于地震资料的流体识别技术研究[D]成都理工大学博士论文,2008年
[31]殷八斤:AVO技术的理论与实践[M].北京:石油工业出版社,l995.
[32]王炳章:地震岩石物理学及其应用研究[D].成都理工大学博士论文,2008年
[33]马中高:碎屑岩地震岩石物理学特征研究[D],成都理工大学博士论文,2008年
[34]杨东全:岩石物理性质和钻柱涡动机理研究[D].北京:清华大学,1999年
[35]朱广生,陈传仁,桂志先:勘探地震学教程[M].武汉大学出版社,2005.
[36]葛瑞·马沃可,塔潘·木克基等:岩石物理手册-孔隙介质中地震分析工具[M].安徽:中国科学技术大学出版社,2008
[37]郝晓红,王闯,谢春雨:流体替代技术及应用分析[J].海洋石油,2008,9(3)1-5
[38]甘利灯:四维地震技术及其在水驱油藏监测中的应用[D],北京:中国地质大学,2002
[39]王荣东:多相介质地震波场模拟与AVO属性分析[D],北京,中国地质大学,2007
[40]武文来,印兴耀:岩石物理参数与地球物理特征关系研究—以QHD326油田为例[J],石油物探,2008,5(3):235-243
[41]胡作维等:储层砂岩波阻抗及拉梅常数实验研究[J].地球科学与环境学报,2006,28(4),54-57.
[42]王家映编著:地球物理反演理论[M].中国地质大学出版社,1998.
[43]李维新,史謌,王红,姚振兴:岩石物理弹性参数规律研究[J].地球物理学进展,2007,22(5),1380-1385.
[44]贺振华,黄德济等:复杂油气藏地震波场特征方法理论及应用[M],四川科学技术出版社,1999
[45]朱广生:地震资料储层预测方法[M].石油大学出版社,1995
[46]万明浩,秦顺亭等:岩石物理性质及其在石油勘探中的应用[M],地质出版社,1994
[47]黄凯,徐群洲,杨晓海等:纵、横波在岩石中的传播速度比及弹性模量与岩石所含流体的关系[J].新疆石油地质,1998,19(5):369-371.
[48]李录明,李正文著:地震勘探原理、方法及解释[M].地质出版社,2007.
[49]石玉梅等:弹性参数在岩性油气藏勘探中的应用_以苏里格气田为例[J].中国石油勘探,2006,11(4):80-84.
[50] Fred J. Hilterman著,孙夕平,赵良武等译:地震振幅解释[M].石油工业出版社,2006
[51]贺振华,黄德济:缝洞储层的地震检测和预测[J],勘探地球物理进展,2003,26(2):79-83.
[52]陈信平,刘素红:浅谈Gassmann方程[J],中国海上油气(地质),1996,10(2):122-127.