【作者】 解建建；

【导师】 王绪本； 程冰洁；

【作者基本信息】 成都理工大学 ， 地球探测与信息技术， 2011， 硕士

【摘要】 地层中裂缝的渗透性相对较好，裂缝不但是油气的储集空间，而且是油气的运移通道，也就是说，地层中裂缝的发育程度和连通性决定了油气富集程度，因此，寻找构造相对稳定的裂缝发育区是构造岩性油气藏勘探成败的关键。裂缝介质是诱导方位各向异性的主要因素，横波对裂缝各向异性介质相当敏感。当横波进入裂缝各向异性介质时会发生横波分裂现象，会分裂成偏振方向相互垂直的两个横波，它们以不同的速度传播，沿着裂缝传播的横波为快横波S1，垂直裂缝传播的横波为慢横波S2。横波分裂这一现象不但可以用来勘探裂缝的角度，还可以用来探测裂缝的发育密度。因此，利用转换波资料中的横波分裂现象可以方便地研究裂隙介质，探测裂隙型油气藏。论文研究内容主要包括研究裂缝的分类与形成机理、裂缝各向异性介质理论、裂缝检测技术等三个部分。文中简要介绍裂缝的分类及形成机理，并且从数值模拟的角度研究裂缝各向异性特征，进而推导出裂缝发育密度与时差的关系。论文的重点是详细介绍横波分裂分析方法，包括裂缝方位的检测技术及裂缝各向异性的校正技术等两个方面的内容。裂缝检测方法包括：能量比值法、极性反转法、最小二乘拟合法、角度谱扫描法等四种方法；快横波、慢横波分离的两种方法：三角变换法、Alford正交旋转法。在完成这些理论研究后，本文作者从研究各种横波分裂技术的方法的原理入手，重点是Alford正交旋转法，首先，Alford正交旋转法应用于多层HTI（horizontal transverse isotropy）介质理论模型中进行测试，横波分裂技术在理论模型的测试说明：在没有噪声的情况下（高信噪比），浅层与深层裂缝方位角度计算值与理论值相符，浅层与深层横波分裂时间延迟计算值与理论值相符，这验证了Alford正交旋转算法的可行性与精确性,可以通过文中的裂缝技术,较为准确地求取上覆各向异性介质情况下目的层的裂缝方位和发育密度,并能够处理多层各向异性裂缝介质情况下的裂缝方位和密度预测问题。在实际的宽方位3D3C地震资料中,快横波和慢横波的偏振方向、传播速度(或者时间延迟)、频谱与振幅属性均受到裂缝发育的方位角、裂缝发育密度、裂缝中填充流体类型的影响。通过对横波分裂的分析和计算,有助于检测裂缝走向和发育程度、辨别裂缝中填充的流体类型等,实现实际资料多层裂缝介质的方位各向异性校正处理,从而达到提高转换波叠加剖面的分辨率的作用。通过对该技术的研究说明Alford正交旋转技术可以应用于实际资料,能够对裂缝的角度和发育密进行有效的预测,进行横波分裂方位各向异性校正处理,对提高多波多分量资料处理水平、提高裂缝储层预测的可靠性及进一步提高深层致密裂缝型气藏勘探开发效益具有非常重要的意义。更多还原

【Abstract】 Strata in the cracks are relatively good, fracture not only is the reservoir space ofoil and gas. but also is the transportation channel of oil and gas, that is to say, thedegree of fracture development in the ground and connectivity of fracture decide theenrichment degree of oil and gas, therefore, looking for the relatively stabledfracture that development zone is the key factor of looking for oil and gas explorationactivity success or failure.Fractured medium is a kind of typical azimuth anisotropic medium,compressional wave is not sensitive spreading on the fracture anisotropic medium, butshear wave is quite sensitive spreading on the fracture anisotropic medium. The shearhappens split phenomenon when it is spreading into the crack anisotropic medium, itwill split into two waves those polarizations are orthogonal components, they havedifferent speeds the shear wave that spread along the crack is defined quickly shearwaves S1, he shear wave that spread vertical cracks is defined slow shear waves S2.Shear wave split phenomenon not only can be used to predicting angle of crack, butalso can be used to explorate the development dimension of cracks. Therefore, shearwave split phenomenon can be used research fissure medium conveniently mediumconveniently, and detect fissure reservoir.The research contents of this paper mainly includes that research crackclassification and formation mechanism, crack anisotropic medium theory, shearsplitting analysis technology and so on three parts. In this paper we will brieflyintroduce crack classification and formation mechanism and we study crackanisotropic characteristics from numerical simulation, Further we deduced with therelationship of fracture developing density is and time difference. Papers areintroduced in detail is the focus of Shear wave splitting analysis method. IncludingFracture forecast technology and crack anisotropic correction technique in the twoaspects of content. Fracture forecast technology include those as follows.Energy ratio method.Polarity reversal method.the Least Square Fitting method and Angle spectralscanning method etc four methods Separation fast-wave and slow-wave have twomethods including Triangle transformation method and Alford orthogonal rotationmethod After completing these theory research The author from the study method ofshear division of the principle of technology Emphasis is Alford orthogonal rotationmethod Alford orthogonal was applied in the theoretical model, the application oftechnology in theory model explain those when profile without noise: (highsignal-to-noise ratio), the Angle of shallow and deep that we calculate match with thetheoretical the time delay of shallow and deep that we calculate match with thetheoretical it tests and verifies the feasibility and accuracy of Alford orthogonalrotating method.we can use fracture forecast technology to accurately calculating theoverlying anisotropic medium cases objective stratum of fracture azimuth anddevelopment density.we can use fracture forecast technology to accurately calculatefracture azimuth and development density of the objective overlying anisotropicmedium.we can able to deal with fracture azimuth and development density predictionproblem of multi-layer anisotropic.In actual 3D3C wide azimuth seismic data, fast andslow shear waves of polarization direction, propagation speed (or time delay),spectrum by fracture development with amplitude attributes the azimuth, fracturedevelopment density, a crack in the influence of filled fluid type. Based on the sheardivision of the calculation and analysis of attribute, facilitate testing fracture trend anddevelopment level, distinguish a crack in the fluid type filling etc.Finally, we usedshear split technology applied to shear three-component and three dimensional actualdata in sichuan, it can realize that this method can correction fractured mediumazimuth anisotropic of multilayer fractured, so as to improve the resolution of theconverted wave stacked profile.Alford orthogonal rotating can be applied in the actual material, able toeffectively predict crack Angle and development effectively, shear splitting can usedazimuth anisotropic correction processing, this has the extremely vital significance inimproving multi-component material processing level, improving the feasibility ofcrack prediction reliability and reservoir prediction reliability and further improve thedeep density fractured reservoir exploration and further improve the deep densityfractured reservoir exploration and development benefits has the extremely vitalsignificance .更多还原