José M Carcione

OGS Istituto Nazionale di Oceanografia e di Geofisica Sperimentale · Geophysics

The low-resolution CT scan images obtained from drill core generally struggle with problems such as insufficient pore structure information and incomplete image details. Consequently, predicting the permeability of heterogeneous reservoir cores relies heavily on high-resolution CT scanning images. However, this approach requires a considerable amou...

Permeability is a critical parameter for evaluating reservoir properties, and accurate prediction is an important basis for identifying high-quality reservoirs and geological modeling. However, the strong heterogeneity, complex lithology and diagenesis in the reservoirs of this region pose a major challenge for the accurate assessment of reservoir...

The quality factor Q is a dimensionless measure of the energy loss per cycle of a wave field, and a proper understanding of this factor is important in a variety of fields, from seismology, geophysical prospecting to electrical science. Here, the focus is on viscoelasticity. When interpreting experimental values, several factors must be taken into...

Underground carbonate deposits are widespread worldwide and have considerable hydrocarbon potential. They are generally characterized by a complex microscopic structure that affects the properties of the macroscopic fluid flow and the relevant petrophysical behavior. In recent years, advances in digital technology have helped reveal the microstruct...

The complex seismic responses of heterogeneous reservoirs can be related to the fabric structure, pore/microcrack shape, mineral composition and fluid distribution of the rock in situ. The pore structure refers to the geometric shape, size, spatial distribution and interconnectedness of pores, microcracks and throats. It is closely related to the s...

We develop a modified fluid-saturated thermoporoelastic model by introducing two temperature equations to account for the temperature differences between the solid skeleton and the pore filling. The modified two-temperature-generalized thermoporoelastic (TTG) equation is an extension of the classical single-temperature (ST) Lord-Shulman (LS), Green...

The rheological models of Lomnitz and Jeffreys have been widely used in earthquake seismology (to simulate a nearly constant Q medium) and to describe the creep and relaxation behavior of rocks as a function of time. Other similar models, such as those of Becker, Scott Blair and Kolsky, show similar properties, particularly the Scott Blair model de...

We develop a numerical algorithm for simulation of wave propagation in anisotropic thermoelastic media, established with a generalized Fourier law of heat conduction. The wavefield is computed by using a grid method based on the Fourier differential operator and a first-order explicit Crank-Nicolson algorithm to compute the spatial derivatives and...

We model the acoustics of rocks partially saturated with hydrogen. We compare the acoustic properties of H2 (hydrogen), CO2 (carbon dioxide) and CH4 (methane) and those of rocks saturated with these gases and brine. The gas properties are obtained from the Peng-Robinson equation of state, and we consider the pressure-temperature conditions based on...

Mesoscopic P-wave attenuation in layered, partially saturated thermo-poroelastic media is analyzed by combining the theories of Biot poroelasticity and Lord–Shulman thermoelasticity (BLS). The attenuation is quantified by estimating the quality factor Q. The mesoscopic attenuation effect, commonly referred to as wave-induced fluid flow (WIFF), is t...

Temperature and pressure variations during the geologic diagenesis process can lead to complex pore structures in tight rocks. The effective-medium theory, based on the stress–strain relationship in combination with pore structure parameters, can be used to describe the elastic-wave responses of rocks. In this work, the differential effective mediu...

The nonlinear characteristics of the rock transport properties (permeability and electrical conductivity in this study) as a function of stress are closely related to the geometry of the pore space, which consists of stiff pores, microcracks, or microfractures. We consider two behaviors of the pore space, one linear and the other exponential, relat...

We perform seismic and ultrasonic measurements in carbonate and shaley sandstone samples as a function of differential pressure. The velocities show a strong frequency and pressure dependence. The dispersion disappears with increasing pressure and the squirt flow in turn inhibits the pressure dependence. To model these effects, we combine the Gurev...

The tight oil/gas reservoirs in China have showed the great exploration prospects and high production potential, with the characteristics of low porosity, low permeability, and significant heterogeneity in formation rocks. It remains a challenge to sort out the relations between reservoir wave responses and rock physical properties, and the further...

We estimate the seismic attenuation of P and S waves in the polar firn and underlying ice by spectral analysis of diving, refracted, and reflected waves from active-source three-component seismic signals obtained in 2010 on the Whillans Ice Stream (WIS), a fast-flowing ice stream in West Antarctica. The resulting quality factors are then successful...

The finite-difference frequency domain (FDFD) method is widely applied for simulating seismic wavefields, and a key to achieving successful FDFD simulation is to construct FDFD coefficients that can effectively suppress numerical dispersion. Among the existing FDFD coefficients for seismic wavefield simulation, adaptive FDFD coefficients that vary...

Geometric heterogeneities in tight reservoir rocks saturated with a fluid mixture may exhibit different scale distribution characteristics. Conventional models of rock physics based on poroelasticity, which usually consider single‐scale pore structure and fluid patches, are inadequate for describing elastic wave responses. A major challenge is to e...

The shale oil reservoir within the Yanchang Formations of Ordos Basin harbors substantial oil and gas resources and has recently emerged as the primary focus of unconventional oil and gas exploration and development. Due to its complex pore and throat structure, pronounced heterogeneity, and tight reservoir characteristics, the techniques for conve...

Petrophysics and fluid-flow simulations are used to build a realistic pre- and post- CO\(_2\) injection geological model for the Utsira formation at the Sleipner field, and the Fourier pseudospectral method is employed to compute synthetic seismograms. The methodology can be used to perform a seismic sensitivity analysis for the detection of carbon...

Seismic wave propagation is affected by wave‐induced local fluid flow between stiff pores and multiscale fractures. To investigate this phenomenon, forced vibration (1–100 Hz) and ultrasonic (10⁶ Hz) measurements are performed on two tight sandstones with complex pore geometry in dry and water‐saturated scenarios. Porosity, permeability, and ultras...

We simulate variations in the P- and S-wave velocities due to CO2 injection in basalt, caused by water replacement and mineralization in the form of carbonate cements. Carbonization can be monitored with seismic data on the basis of changes in velocity. We consider basalts composed of (Fe, Ca and Mg) minerals mainly, and the pore space is assumed t...

Deep carbonate reservoirs are subject to in-situ conditions of high temperature and high pressure. We consider six water-saturated dolomite specimens from these reservoirs and perform ultrasonic experiments to obtain the P- and S-wave waveforms and velocities at different pressure and temperature conditions. The P-wave attenuation is estimated with...

We study the reflection and transmission (R/T) characteristics of inhomo�geneous plane waves at the interface between two dissimilar fluid-saturated thermo�poroelastic media at arbitrary incidence angles. The R/T behaviors are formulated based on the classic Lord-Shulman (LS) and Green-Lindsay (GL) heat-transfer models as well as a generalized LS m...

The theory of wave propagation in non-isothermal porous rocks has been introduced in geophysics in recent years by combining the single-phase-lag (SPL) Lord-Shulman (LS) model of heat conduction with Biot’s poroelasticity theory. However, the theory of SPL thermoporoelasticity is inadequate in describing the lagging behavior of thermal relaxation f...

We develop a numerical algorithm for simulation of wave propagation in anisotropic thermoelastic media, established with a generalized Fourier law of heat conduction. The wavefield is computed by using a grid method based on the Fourier differential operator and a first-order explicit Crank-Nicolson algorithm to compute the spatial derivatives and...

We study the anelastic properties (attenuation and velocity dispersion) of surface waves at an interface between a finite water layer and a porous medium described by Biot theory including the frequency-dependent effects due to mesoscopic flow. A closed-form dispersion equation is derived, based on potential functions and open and sealed boundary c...

We analyze the management of the Italian pandemic during the five identified waves. We considered the following problems: (i) The composition of the CTS ("Scientific Technical Committee"), which was composed entirely of doctors, mainly virologists, without mathematical epidemiologists, statisticians, physicists, etc. In fact, a pandemic has a behav...

We consider surface-wave propagations at an interface separating a fluid layer and a double-porosity medium embedded with cracks. The theory is based on a generalization of the Biot-Rayleigh model from spherical cavities to penny-shaped cracks randomly embedded into a host medium, where mesoscopic local fluid flow (LFF) plays an important role. We...

In recent years, the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics, low porosity and low permeability, and weak anomalies for oil and water discriminations, have been the key targets of unconventional oil/gas resource exploration and development in the relevant areas. The...

We estimate the P- and S-wave seismic attenuation in polar firn from spectral analysis of diving-wave first-breaks of three-component active-source seismic observations carried out in 2010 on the Whillans Ice Stream (WIS), a fast-flowing ice stream in West Antarctica. The resulting quality factors are then successfully modeled using a rock-physics...

p>Seismic AVO has a significant potential for fluid identification in time-lapse monitoring of the cyclic recovery of geothermal reservoirs. With this goal, we develop an AVO method based on the reflection and transmission (R/T) of elastic waves at an interface between two fluid-saturated thermo-poroelastic media. The method is applied to the Olkar...

We investigate the anelastic dispersion and attenuation of P- and SV-wave scattering by non-isothermal cracks of finite thickness. The cracks, which are aligned and sparsely embedded in an isotropic medium, induce an initial static stress field (acoustoelasticity) and a nonlinear dependence of the velocities on this stress. Moreover, we describe th...

Fractured-vuggy thermal reservoirs with a complex pore space (stiff pores, cracks and fractures) are a typical geothermal resource for development and utilization in China. The cyclic recovery of such thermal reservoirs involves a complex thermo-hydro-mechanical (THM) coupling process. Insights into the thermoelastic effects of heating-cooling cycl...

Tight reservoirs are distributed in several basins in China, with great exploration prospects and high production potential. These reservoirs have low porosity and permeability and a significant spatial heterogeneity, and this complexity requires new developments on the experimental and theoretical researches of wave propagation. To this purpose, w...

P-wave anelasticity (attenuation and dispersion) of hydrate-bearing sediments depends on several factors, namely the properties of the mineral components, hydrate content and morphology, and fluid saturation. Anelasticity is analyzed with a triple-porosity model (stiff pores, clay micropores and hydrate micropores), by considering hydrate as an add...

We investigate the effect of temperature on the elastic properties of rocks by combining the thermal-damage factor (TDF) with the Gassmann equation. The resulting model is tested in carbonate samples by analyzing the ultrasonic wave velocity. A comparison between the estimated and measured TDF shows that the model quantitatively describes the behav...

The elastic stress–strain relation of deep source rocks must account for the presence of fractures and lamination due to thermally mature kerogen layers. Clay lamination describes the variation in transverse isotropy with a vertical symmetry (VTI) characteristic of shale background, and vertical fractures induce the transverse isotropy with a horiz...

The elastic properties of rocks depend on the mineral constituents, pore structure, saturating fluids, and stress (loading) conditions. To study these properties, we measured ultrasonic P‐ and S‐wave velocities as a function of the differential (confining minus pore) pressure and propose an unrelaxed double‐porosity acoustoelasticity model, which g...

p>Temperature is an important factor for evaluating the seismic response of deep reservoirs. We develop an amplitude variation with offset (AVO) approximation based on the Lord-Shulman (LS) thermoelasticity theory. The model predicts two compressional (P and T) waves (the second is a thermal mode) and a shear (S) wave. The T mode is due to the coup...

p>Temperature is an important factor for evaluating the seismic response of deep reservoirs. We develop an amplitude variation with offset (AVO) approximation based on the Lord-Shulman (LS) thermoelasticity theory. The model predicts two compressional (P and T) waves (the second is a thermal mode) and a shear (S) wave. The T mode is due to the coup...

Temperature is an important factor for evaluating the seismic response of deep reservoirs. We develop an amplitude variation with offset (AVO) approximation based on the Lord-Shulman (LS) thermoelasticity theory. The model predicts two compressional (P and T) waves (the second is a thermal mode) and a shear (S) wave. The T mode is due to the coupli...

The prediction of the pore geometrical properties is important in the exploration and development of tight-sandstone hydrocarbon reservoirs. To investigate this topic, we have measured the porosity, permeability, P- and S-wave velocities, electrical conductivity, and axial and radial strains as a function of differential (confining minus pore) pres...

This chapter illustrates the most used numerical methods to solve wave and diffusion equations, including fractional derivatives. To solve the equations, the model is approximated by a numerical mesh. These algorithms are called grid and full-wave equation methods, since the solution implicitly gives the full wave field. Direct methods do not have...

This chapter focuses on the reflection-transmission problem in anisotropic viscoelastic media. In general, the reflected and transmitted waves are inhomogeneous. The reflected wave is homogeneous only when the symmetry axis is perpendicular to the interface. The relevant physical phenomena are not related to the propagation direction (slowness vect...

This chapter considers isotropy and viscoelasticity. Attenuation is introduced in the form of the Boltzmann superposition law, which implies a convolutional relation between stress and strain through the relaxation and creep matrices. Mostly, the analysis is restricted to the one-dimensional case, where some of the consequences of anelasticity beco...

The effects of the space dimension are considered in this chapter, revealing other properties of wave fields. The attenuation vector plays a role at the same level as the wavenumber vector. Snell law, for instance, implies continuity of the tangential components of both vectors at the interface of discontinuity. For inhomogeneous viscoelastic waves...

The combined effect of anisotropy and viscoelasticity is the subject of this chapter, where the first problem is to obtain the time dependence of the relaxation components based on physical grounds. Fine layering has an “exact” description in the long-wavelength limit. The concept of eigenstrain allows us to limit the number of relaxation functions...

Reciprocity is usually applied to concentrated point forces and point receivers. However, reciprocity has a much wider application potential; in many cases, it is not used at its full potential because either a variety of source and receiver types are not considered, or their implementation is not well understood. In this chapter, the reciprocity r...

This chapter explores the analogy between the fields of acoustics and electromagnetism. The two-dimensional Maxwell equations are equivalent to the SH-wave equation based on the Maxwell mechanical model. It is shown that Fresnel formulae can be obtained from the reflection and transmission coefficients of shear waves. The layer problem illustrates...

Wave propagation in anisotropic lossless media is the subject of this chapter. In anisotropic media, the directions of the wavevector and power-flow vector do not coincide. This implies that the phase and energy velocities differ. However, some ideal properties prevail: there is no dissipation, the group-velocity vector is equal to the energy-veloc...

Biot theory is the basis to describe wave propagation in porous media, starting with Terzaghi law, Gassmann equation, and the static approach leading to the concept of effective stress, much used in soil mechanics. The coefficients of the strain energy are obtained by the so-called jacketed and unjacketed experiments. The theory includes anisotropy...

The wave-induced local fluid flow mechanism is relevant to the complex heterogeneity of pore structures in rocks. The analysis of the local fluid flow mechanism is useful for accurately describing the wave propagation characteristics in reservoir rocks. In the exploration and production of hydrocarbon reservoirs, the real stratum may be partially s...

Fracture-induced azimuthal anisotropy of seismic waves has useful applications in the characterization of hydrocarbon reservoirs as well as the overburden. Existing theories face problems estimating the fracture-weakness parameters, identifying the saturating fluid, and constraining the depth model building. To overcome these problems, we have adop...

The acoustic-electrical (AE) response of subsurface hydrocarbon reservoirs is highly affected by rock heterogeneity. In particular, the characterization of the microstructure of tight (low-permeability) rocks can be aided by a joint interpretation of AE data. To this purpose, we evaluate cores from a tight-oil reservoir to obtain the rock mineralog...

The Lord-Shulman thermoporoelasticity theory couples the Biot and hyperbolic heat equations to describe wave propagation, modeling explicitly the effects of heat and fluid flows. We extend the theory to the case of double porosity by taking into account both the local heat flow (LHF) and local fluid flow (LFF) due to wave propagation. The plane-wav...

We obtain the amplitude and energy reflection coefficients of seismic waves in porous media with penny-shaped inclusions, based on the generalized Biot-Rayleigh model that takes into account the attenuation due to mesoscopic local fluid flow (LFF). We consider two cases, including a contact between two porous media having either different fluids (g...

The important consequence of the Kramers-Kronig relations (KKrs) is that dissipative behavior in material media inevitably implies the existence of dispersion, i.e., a frequency dependence in the constitutive equations. Basically, the relations are the frequency-domain expression of causality and correspond mathematically to pairs of Hilbert transf...

Thermoelastic attenuation of P waves is due to energy conversion to the heat mode, which is diffusive at low frequencies and wave-like at high frequencies, behaving similarly to the Biot slow mode. The conversion is strong in highly heterogeneous media. We consider a layered medium with a random distribution of thermal properties, specifically the...

We simulate the effects of diagenesis, cementation and compaction on the elastic properties of shales and sandstones with four different petro-elastic theories and a basin-evolution model, based on constant heating and sedimentation rates. We consider shales composed of clay minerals, mainly smectite and illite, depending on the burial depth, and t...

High temperature affects the seismic properties of cracked and faulted reservoirs and can be an indicator for their detection. To this purpose, we study the wave-induced thermal flux (WITF) and develop two exact solutions for the scattering of compressional waves by a circular crack filled with a compressible fluid, where the approach is based on t...

We study the reflection and transmission coefficients of plane waves incident at an interface between two isotropic thermoelastic half spaces and compare them with those of the elastic case. The models include the classical-Biot (B) and extended Lord-Shulman (LS) theories, and predict reflected and transmitted fast-compressional (P), thermal (T) an...

Laboratory experiments on partially saturated rocks show that seismic attenuation can be significant. The main mechanism, wave‐induced local fluid flow (WILFF), is affected by the spatial fluid distribution, especially in conditions of patchy saturation at different spatial scales. We propose a theory to obtain the seismic properties of partially s...

Understanding the dependence of the rock properties on temperature is essential when dealing with heavy oil reservoirs. Reported rock physics models can hardly capture the effect of temperature on wave velocities. We propose a dual-porosity temperature-dependent model based on the coherent potential approximation, combining temperature- and frequen...

Petrophysical seismic inversion, aided by rock physics, aims at estimating reservoir properties based on reflection events, but it is generally based on the Gassmann equation, which precludes its applicability to complex reservoirs. To overcome this problem, we present a methodology based on the double-porosity Biot–Rayleigh (BR) model, which takes...

The absence of shear-wave (S-wave) log data restricts the geophysical characterization and fluid identification of Chang 7 shale-oil reservoirs in Ordos Basin, and we have to make use of suitable rock-physics theories to overcome this problem. We reformulate the Xu-White model by combining the critical-porosity and Maxwell-BISQ models to predict th...

In many cases, multilayered media with flat interfaces are a suitable representation of the geologic features of the crust. In general, the isothermal theory is used, and the transfer-matrix (TM) method is applied to compute the scattering reflection and transmission (R/T) coefficients. We have generalized the TM algorithm to the more general case...

Tight sandstones have low porosity and permeability and strong heterogeneities with microcracks, resulting in small wave impedance contrasts with the surrounding rock and weak fluid-induced seismic effects, which make the seismic characterization for fluid detection and identification difficult. For this purpose, we propose a reformulated modified...