The fluid term in the Biot-Gassmann equation plays an important role reservoir discrimination. density imbedded term, however, is difficult to estimate because it less sensitive seismic amplitude variations. We combined poroelasticity theory, variation with offset (AVO) inversion, and identification of P- S-wave moduli present a stable physically meaningful method no need for information from prestack data. used theory express as function moduli. use made derivation natural. Then we derived...

Fluid indicators estimated from seismic data play important roles in reservoir characterization and prospect identification. Traditionally, there are a variety of fluid proposed, but they very likely to provide ambiguous results for identification due the fact that their sensitivity is dependent upon mixed effect pore rock porosity. To raise indication, we used effective pore-fluid bulk modulus as indicator. Starting with poroelastic amplitude variation offset (AVO) theory corresponding...

Young’s modulus and Poisson’s ratio are related to quantitative reservoir properties such as porosity, rock strength, mineral total organic carbon content, they can be used infer preferential drilling locations or sweet spots. Conventionally, computed estimated with a physics law in terms of P-wave, S-wave impedances/velocities, density which may directly inverted prestack seismic data. However, the term imbedded is difficult estimate because it less sensitive seismic-amplitude variations,...

Abstract The elastic moduli of subsurface rocks saturated with geofluid often depend on the wave frequency and confining pressure due to wave‐induced fluid flow their significant intrinsic compressibility. Therefore, knowledge pressure‐dependent dispersion is usually used in broad practical scenarios such as discrimination situ abnormal detection. We propose a simple dual‐porosity model describe dependence fluid‐saturated rocks. First, we follow idea Shapiro yield more accurate formulas for...

Summary Due to the significant differences between shale reservoir and conventional sand in many aspects such as types characteristics of minerals, pores fluids, existing rock physics models are no longer applicable for reservoir. In order make a better description gas reservoir, new effective model, which is more suitable was proposed this work. One assumption used that clay considered be background medium, other organic matter, fluids seen inclusions. And well A verify reliability model....

Seismic inversion is an important approach in parameters estimation the fields of geosciences. The low-frequency component model parameter plays role seismic inversion. emergence broadband data acquisition and processing technologies pushing attention low frequency to a new level. With review research status models history contained complex domain, novel Bayesian domain proposed implement parameter. makes full use advantage damped wave domain. kernel function built with inference. Synthetic...

Elastic impedance (EI) and amplitude variation with offset or angle (AVO/AVA) inversion are two cardinal methods to estimate elastic parameters underground reflection seismic data. Conventional EI as a kind of pre-stack post-stack joint method has been widely applied in the industry because its high efficiency stability wavelet extraction; however, robustness extracting conventional is still controversial. The three-term AVO improved lot; it challenging extract reasonable space variant...

The normal-to-tangential fracture compliance ratio is usually used as a fluid indicator (FFI) for identification in fractured reservoirs. With new parameterization weaknesses, we have defined FFI based on azimuthally anisotropic elastic impedance (EI) inversion and rock-physics models. First, derived EI equation with similar expression the isotropic parts to remove exponential correction of that attributable weak anisotropy. Then, built model estimation well-log parameters normal tangential...

A linearized rock physics inversion method is proposed to deal with two important issues, physical model and algorithm, which restrict the accuracy of inversion. In this method, first, complex expanded into Taylor series get first-order approximate expression inverse problem physics; then damped least square used solve directly analytical solution problem. This does not need global optimization or random sampling, but calculates operation, high computational efficiency. The theoretical...

Seismic reservoir prediction plays an important role in oil exploration and development. With the progress of artificial intelligence, many achievements have been made machine learning seismic prediction. However, due to factors such as economic cost, maturity, technical limitations, it is often difficult obtain a large number training samples for learning. In this case, accuracy cannot meet requirements. To overcome shortcoming, we develop new method based on virtual sample generation....

SUMMARY The stress-dependent wave reflection and transmission (R/T) coefficients for the layered transversely isotropic media with a vertical symmetry axis (VTI) are seldom investigated in published literature. To fill this gap, we propose exact formulas plane R/T on welded non-welded boundaries between two distinct VTI half-spaces under effect of initial stress. theory acoustoelasticity is used to describe influence applied stress overall elastic properties represent different boundary...

Seismic amplitude variation with offset (AVO) inversion is well-known as a popular and pragmatic tool used for the prediction of elastic parameters in geosciences. Low frequencies missing from conventional seismic data are conventionally recovered other geophysical information, such well-log data, estimating absolute rock properties, which results biased cases complex heterogeneous geologic targets or plays sparse marine deep stratum. Broadband bring new opportunities to estimate...

Brittleness of rock plays a significant role in exploration and development shale gas reservoirs. Young's modulus Poisson's ratio are the key parameters for evaluating brittleness because their combination relationship can quantitatively characterize brittleness. The high-value anomaly low-value represent high shale. technique pre-stack amplitude variation with angle inversion allows geoscientists to estimate from seismic data. A model constrained basis pursuit method is proposed stably...

Reservoir lithology identification is critical to reservoir characterization, reserves calculation, and geological modeling. The deep learning method a data-driven algorithm for establishing the relationship between lithology-sensitive properties litho-types from large amount of observed data. label inadequate high drilling core recovery costs. Consequently, we propose based on improved adversarial relieve overfitting problem multi-solution caused by labeled data massive learnable parameters...

Stratum quality factors (P-wave and S-wave factors, Qp Qs) have gradually been utilized in the study of physical state crust uppermost mantle, tectonic evolution, hydrogeololgy, gas hydrates, petroleum exploration, etc. Different opinions seismic attenuation mechanism result various approaches to estimate P-wave factors. Considering viscoelasticity underground medium, constitutive matrix Earth medium is written as superposition homogeneous background elastic perturbation viscoelastic medium....

Subsurface fractures within many carbonates and unconventional resources play an important role in the storage movement of fluid. The more reliably detection could be performed, finely reservoir description made. In this paper, we aim to propose a method which uses two tools, fractured anisotropic rock physics effective model AVAZ (amplitude versus incident azimuthal angle) inversion, predict from seismic data. We assume that rock, contains one or sets vertical sub-vertical fractures, shows...