In this paper, an explicit finite element method to analyze the dynamic responses of three-medium coupled systems with any terrain is developed on the basis of the numerical simulation of the continuous conditions on ...In this paper, an explicit finite element method to analyze the dynamic responses of three-medium coupled systems with any terrain is developed on the basis of the numerical simulation of the continuous conditions on the bounda-ries among fluid saturated porous medium, elastic single-phase medium and ideal fluid medium. This method is a very effective one with the characteristic of high calculating speed and small memory needed because the formulae for this explicit finite element method have the characteristic of decoupling, and which does not need to solve sys-tem of linear equations. The method is applied to analyze the dynamic response of a reservoir with considering the dynamic interactions among water, dam, sediment and basement rock. The vertical displacement at the top point of the dam is calculated and some conclusions are given.展开更多
The perfectly matched layer（PML） was first introduced by Berenger as an absorbing boundary condition for electromagnetic wave propagation.In this article,a method is developed to ex-tend the PML to simulating seismi...The perfectly matched layer（PML） was first introduced by Berenger as an absorbing boundary condition for electromagnetic wave propagation.In this article,a method is developed to ex-tend the PML to simulating seismic wave propagation in fluid-saturated porous medium.This non-physical boundary is used at the computational edge of a Forsyte polynomial convolutional differenti-ator（FPCD） algorithm as an absorbing boundary condition to truncate unbounded media.The incor-poration of PML in Biot＇s equations is given.Numerical results show that the PML absorbing bound-ary condition attenuates the outgoing waves effectively and eliminates the reflections adequately.展开更多
According to generalized characteristic theory, a characteristic analysis for stress wave propagation in transversely isotropic fluid-saturated porous media was performed. The characteristic differential equations an...According to generalized characteristic theory, a characteristic analysis for stress wave propagation in transversely isotropic fluid-saturated porous media was performed. The characteristic differential equations and compatibility relations along bicharacteristics were deduced and the analytical expressions for wave surfaces were obtained. The characteristic and shapes of the velocity surfaces and wave surfaces in the transversely isotropic fluid-saturated porous media were discussed in detail. The results also show that the characteristic equations for stress waves in pure solids are particular cases of the characteristic equations for fluid-saturated porous media.展开更多
AVA(Amplitude Versus Angle)技术是基于常规介质模型(均匀各向同性介质模型)发展起来的,由于忽略了储层的孔隙结构和充填流体的影响,造成AVA特征中是部分对地震波能量的吸收和衰减作用反映不足。从振幅特征方程的实际应用出发,建立起...AVA(Amplitude Versus Angle)技术是基于常规介质模型(均匀各向同性介质模型)发展起来的,由于忽略了储层的孔隙结构和充填流体的影响,造成AVA特征中是部分对地震波能量的吸收和衰减作用反映不足。从振幅特征方程的实际应用出发,建立起各参数与常规岩性参数之间的关系。以Gassmann方程与Biot理论为基础,推导出振幅特征方程中弹性参数与常规岩性、储层参数(如:纵波速度、横波速度、密度、孔隙度、流体参数Kf)之间的转化关系式,详细研究饱和流体多孔介质模型中的AVA特征,比较该介质模型与常规介质模型在AVA特征上的差异,并将饱和流体多孔介质AVA技术应用于川西凹陷深层须家河组储层预测,通过多波AVA储层参数的反演研究,为直接利用地震资料进行储层识别并进一步识别其流体特征提供了一种有力手段。展开更多
基金National Natural Scienccs Foundation of China (50178005).
文摘In this paper, an explicit finite element method to analyze the dynamic responses of three-medium coupled systems with any terrain is developed on the basis of the numerical simulation of the continuous conditions on the bounda-ries among fluid saturated porous medium, elastic single-phase medium and ideal fluid medium. This method is a very effective one with the characteristic of high calculating speed and small memory needed because the formulae for this explicit finite element method have the characteristic of decoupling, and which does not need to solve sys-tem of linear equations. The method is applied to analyze the dynamic response of a reservoir with considering the dynamic interactions among water, dam, sediment and basement rock. The vertical displacement at the top point of the dam is calculated and some conclusions are given.
基金supported by the National Natural ScienceFoundation of China (No. 40804008)
文摘The perfectly matched layer（PML） was first introduced by Berenger as an absorbing boundary condition for electromagnetic wave propagation.In this article,a method is developed to ex-tend the PML to simulating seismic wave propagation in fluid-saturated porous medium.This non-physical boundary is used at the computational edge of a Forsyte polynomial convolutional differenti-ator（FPCD） algorithm as an absorbing boundary condition to truncate unbounded media.The incor-poration of PML in Biot＇s equations is given.Numerical results show that the PML absorbing bound-ary condition attenuates the outgoing waves effectively and eliminates the reflections adequately.
文摘According to generalized characteristic theory, a characteristic analysis for stress wave propagation in transversely isotropic fluid-saturated porous media was performed. The characteristic differential equations and compatibility relations along bicharacteristics were deduced and the analytical expressions for wave surfaces were obtained. The characteristic and shapes of the velocity surfaces and wave surfaces in the transversely isotropic fluid-saturated porous media were discussed in detail. The results also show that the characteristic equations for stress waves in pure solids are particular cases of the characteristic equations for fluid-saturated porous media.
文摘AVA(Amplitude Versus Angle)技术是基于常规介质模型(均匀各向同性介质模型)发展起来的,由于忽略了储层的孔隙结构和充填流体的影响,造成AVA特征中是部分对地震波能量的吸收和衰减作用反映不足。从振幅特征方程的实际应用出发,建立起各参数与常规岩性参数之间的关系。以Gassmann方程与Biot理论为基础,推导出振幅特征方程中弹性参数与常规岩性、储层参数(如:纵波速度、横波速度、密度、孔隙度、流体参数Kf)之间的转化关系式,详细研究饱和流体多孔介质模型中的AVA特征,比较该介质模型与常规介质模型在AVA特征上的差异,并将饱和流体多孔介质AVA技术应用于川西凹陷深层须家河组储层预测,通过多波AVA储层参数的反演研究,为直接利用地震资料进行储层识别并进一步识别其流体特征提供了一种有力手段。
