Article
Engineering, Geological
Daming Lin, Renmao Yuan, Xiaoling Lin, Xuechun Lin, Chonghua Lou, Yanyan Cai, Jin Yu, Renke Qiu, Xingju Su, Hui Wang
Summary: This study in South China utilized data from 278 shallow boreholes and 12 geophysical exploration lines to establish a 3D geological-geophysical model of disturbed granite, and found quantitative relationships between disturbed rock mass structure and rock core index, as well as between electrical resistivity and seismic velocity of disturbed granite.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Geochemistry & Geophysics
Liwei Cheng, Manika Prasad, Reinaldo J. Michelena, Ali Tura, Shamima Akther, Petar Vladov Angelov, Rao Narhari Srinivasa
Summary: Multimineral log analysis is a quantitative tool used for geologic and petrophysical reservoir characterization. It estimates rock composition by solving equations that relate log measurements to the petrophysical endpoints of minerals and fluids. The method uses effective medium models to validate and constrain the results, providing independent quality control and realistic rock-physics models.
Article
Geochemistry & Geophysics
Tim Matava, Robert G. Keys, Sverre E. Ohm, Stefano Volterrani
Summary: The study investigates hydrocarbon generation in source rocks using a calibrated rock-physics model to predict P- and S-wave velocities and density. It identifies the increase in porosity as a key indicator of source rock maturity and demonstrates the significant amplitude response of a maturing source rock in seismic data. The research provides insight into kerogen kinetics and reduces exploration risk by correlating seismic response with source rock maturity model.
Article
Acoustics
Qian Xu, Zhong-Qi Wang
Summary: The study focuses on the method for computing the seismic wave spectrum excited by explosive sources. It shows that the main frequency and bandwidth of seismic waves caused by explosions are influenced by factors such as initial detonation pressure, adiabatic expansion of the explosive, and geotechnical parameters. The research also highlights the differences in seismic wave characteristics when detonating explosives in different types of soil.
SHOCK AND VIBRATION
(2021)
Article
Geochemistry & Geophysics
Fuyong Yan, De-Hua Han, Qiuliang Yao
Summary: Compared with isotropic media, transversely isotropic media in P-wave seismic data processing and interpretation involve at least two extra parameters. Previous studies have shown the challenges in estimating anisotropy parameters even with low noise level seismic data. Considering the physical relationships between anisotropy parameters can improve the accuracy of estimates during the inversion process.
Article
Geochemistry & Geophysics
Yanbin He, J. German Rubino, Santiago G. Solazzi, Nicolas D. Barbosa, Marco Favino, Tianning Chen, Jinghuai Gao, Klaus Holliger
Summary: We propose a novel coupled fluid-poroelastic model and numerical upscaling procedure to calculate seismic attenuation and velocity dispersion in porous rocks induced by fluid pressure diffusion in the presence of mesoscopic fluid-saturated voids. The proposed approach shows advantages over purely poroelastic models in modeling fluid-saturated mesoscopic voids, and allows for the effects of different types of fluid pressure diffusion in the seismic characteristics of synthetic samples.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Construction & Building Technology
Yunhuo Zhang, Yunyue Elita Li, Taeseo Ku
Summary: Soil/rock interface detection is a critical task in geological site investigation for underground and tunnel projects, requiring high accuracy both vertically and horizontally. This study introduces a new non-invasive geophysical survey method, autocorrelation, to reduce reliance on reference boreholes and achieve the required resolution. The proposed approach can reasonably estimate soil layers' average Vp above the soil/rock interface and produce reasonable 2D and 3D interface profiles. Due to its self-source feature, this approach is convenient for on-site implementation and can be a promising option for geotechnical and geological site investigation.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2021)
Article
Geochemistry & Geophysics
William J. Shinevar, Oliver Jagoutz, Mark D. Behn
Summary: In this study, a tool called WISTFUL is introduced to help researchers analyze seismic datasets by quantitatively converting upper mantle seismic wave speeds into temperature, density, composition, and related parameters. The tool utilizes a large database, MATLAB functions, scripts, and user interfaces to provide features such as plotting relationships, calculating seismic wave speeds, and inverting temperature. The accuracy and sources of error in the methodology are evaluated through comparison of observed and calculated data.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Article
Geosciences, Multidisciplinary
Parisa Shokouhi, Vrushali Girkar, Jacques Riviere, Srisharan Shreedharan, Chris Marone, C. Lee Giles, Daniel Kifer
Summary: Small changes in seismic wave properties can indicate impending frictional failure in laboratory experiments and seismic faults. Deep learning models accurately predict the timing and size of laboratory earthquakes based on wave features, showing potential for seismic hazard assessment and warning. The models developed in this study demonstrate good transferability to unseen datasets, reducing the training time and data required for model development.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Tanner A. Shadoan, Jonathan B. Ajo-Franklin, Yves Guglielmi, Todd Wood, Michelle Robertson, Paul Cook, Florian Soom, Thomas M. Daley, Chet Hopp, Veronica Rodriguez Tribaldos, Pierpaolo Marchesini, Christophe Nussbaum, Jens Birkholzer
Summary: This study conducted a time-lapse seismic experiment to monitor a reactivated fault within the Opalinus clay formation at the Mont Terri Rock Laboratory. The measured changes in P-wave velocity were related to the opening of the fault damage zone, providing insights into changes in permeability within the fault zone. This research is important for predicting, detecting, and preventing CO2 movement.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Engineering, Geological
Feili Wang, Kaiwen Xia, Wei Yao, Shuhong Wang, Chonglang Wang, Zhanguo Xiu
Summary: This study presents an experimental method to simulate slip shear failure along rock discontinuities, conducted by dynamic direct shear experiments using a dynamic shear apparatus combined with a high-speed digital camera. The effects of shear velocity and normal stress on rough rock discontinuities are analyzed, revealing that slip rate is linearly proportional to shear velocity and decreases with increasing normal stress. A dynamic failure criterion is developed considering both surface roughness and dynamic loading, providing a good prediction of the experimental data on the dynamic shear process of rock discontinuities.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Engineering, Geological
Nomqhele Z. Nkosi, Musa S. D. Manzi, Michael Westgate, Dave Roberts, Raymond J. Durrheim, Hiroshi Ogasawara, Martin Ziegler, Michael Rickenbacher, Bennie Liebenberg, Tullis C. Onstott
Summary: This study presents the petrophysical properties of cylindrical core specimens from three boreholes and compares them with downhole petrophysical data. The experimental measurements show that the metasediments exhibit lower densities and seismic velocities than the metabasalts and intrusives. Synthetic seismograms were computed to investigate seismic reflectivity and successfully correlated with the real seismic data.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Geography, Physical
Maria Aurora Natale Castillo, Magdala Tesauro, Mauro Cacace
Summary: Understanding the physical and mechanical properties of the Earth's crust is crucial for assessing its exploitable potential. This study investigates the quantitative relationship between seismic attenuation and viscous rheology of rocks in the transition zone from brittle to ductile deformation. The results demonstrate that shear wave attenuation is more sensitive to strain rate than rock rheology and thermal conditions, allowing for the identification of the average depth of the transition. The findings have implications for tectonically active and geothermal areas.
GLOBAL AND PLANETARY CHANGE
(2022)
Article
Geochemistry & Geophysics
Ilaria Barone, Emanuel Kaestle, Claudio Strobbia, Giorgio Cassiani
Summary: Surface wave tomography is a powerful technique used to retrieve 3D shear-wave velocity models at a regional scale. By applying this technique to 3D active-source data and testing different tomography algorithms, it was found that the Markov chain Monte Carlo (MCMC) algorithm achieved the lowest misfit to the input model. The resulting phase-velocity maps showed good correspondence and highlighted the same geologic structures, leading to the retrieval of a 3D S-wave velocity model through depth inversion of individual dispersion curves.
Article
Geochemistry & Geophysics
Marta Cyz, Leonardo Azevedo
Summary: The purpose of seismic reservoir characterization is to predict the spatial distribution of subsurface rock properties from a set of measurements. This is commonly achieved through a two-step process involving inversion of elastic properties from seismic reflection data and computation of rock properties volumes using calibrated rock physics models. The proposed iterative geostatistical shale rock physics seismic AVA inversion method aims to directly invert seismic reflection data for shale rock properties.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2021)
Article
Geochemistry & Geophysics
Mengqiang Pang, Jing Ba, Li-Yun Fu, Jose M. Carcione, Uti Markus, Lin Zhang
INTERPRETATION-A JOURNAL OF SUBSURFACE CHARACTERIZATION
(2020)
Article
Energy & Fuels
Jose M. Carcione, Davide Gei, Stefano Picotti, M. Shahir Misnan, M. Rashad Amir Rashidi, Zainol Affendi Abu Bakar, Zuhar Zahir Tuan Harith, Nabila Hannah Samsol Bahri, Noorbaizura Hashim
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2020)
Article
Geochemistry & Geophysics
Jia Wei, Li-Yun Fu, Tongcheng Han, Jose M. Carcione
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2020)
Article
Mathematics, Applied
Juan E. Santos, Jose M. Carcione, Jing Ba
Summary: The study demonstrates the existence of a unique solution for wave propagation in linear thermo-poroelastic isotropic media, showing regularity in both space and time variables.
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS
(2021)
Article
Geochemistry & Geophysics
Lin Zhang, Jing Ba, Jose M. Carcione
Summary: The theory developed in this study describes wave propagation in porous media with inclusions at multiple scales, derived from differential effective medium theory and Biot-Rayleigh theory for double-porosity media. The theory determines generalized stiffness and density coefficients based on the first principles of strain, kinetic, and dissipation energies, showing that anelasticity depends on various factors such as inclusion size, distribution parameter, mean radius, and variance. Experimental results confirm the model's validity in describing anelasticity observed in laboratory and field measurements.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Mengqiang Pang, Jing Ba, Jose M. Carcione, Erik H. Saenger
Summary: This study aims to characterize tight-oil reservoirs using a dual-porosity-clay parallel network electrical model and Hashin-Shtrikman and differential effective medium equations elastic model. By analyzing rock samples, log data, and microstructures, the effects of porosity and clay content on the elastic and electrical properties are studied to achieve good agreement between predictions and actual production reports.
Article
Energy & Fuels
Juan Santos, Jose Carcione, Jing Ba
Summary: The study focuses on the wave anelasticity of a periodic set of three flat porous layers saturated by two immiscible fluids. Results show higher dissipation and anisotropy compared to a widely used model that ignores the effects of surface tension and viscous flow interference between the fluid phases.
Article
Geochemistry & Geophysics
Enjiang Wang, Jose M. Carcione, Jing Ba
Summary: In this study, a generalized porothermoelasticity theory is developed to simulate wave propagation in partially saturated nonisothermal media. The results show that the strain field in rocks leads to thermal imbalances and the interfacial tension between fluids affects the acoustic properties. The simulated results are consistent with plane-wave analyses, and the GL model can predict higher thermal attenuation and larger velocity dispersion.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Hui Qi, Jing Ba, Jose M. Carcione, Lin Zhang
Summary: Understanding the dependence of rock properties on temperature is crucial for heavy oil reservoirs. A dual-porosity temperature-dependent model has been proposed, combining empirical equations for pore fluids with the David-Zimmerman model, to quantitatively describe wave velocities behavior with temperature variation. The study also reveals a change in trends of P- and S-wave velocities when reaching a viscosity threshold.
Article
Geochemistry & Geophysics
Lin Zhang, Jing Ba, Jose M. Carcione, Chunfang Wu
Summary: Laboratory experiments have shown that seismic attenuation in partially saturated rocks can be significant. We propose a theory based on fractal patches to describe the seismic properties of partially saturated rocks, which leads to an effective frequency-dependent fluid modulus. The theory takes into account various parameters such as the scale range of the patches, the fractal dimension of the self-similar distribution, and the mean radius and variance of the Gaussian distribution. Experimental data on limestone samples support the validity of the proposed theory.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Fansheng Xiong, Jing Ba, Davide Gei, Jose M. Carcione
Summary: Exploration and exploitation of shale oil is a crucial aspect of the oil industry, and using machine learning techniques to establish wave propagation models can improve accuracy and generality. Two deep-neural-network-based wave propagation models are compared, showing that the new ML-based approach has high precision and broad application potential.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Nianqi Li, Wubing Deng, Li-Yun Fu, Jose M. Carcione, Tongcheng Han
Summary: The Lord-Shulman thermoporoelasticity theory is extended to the case of double porosity, considering the effects of local heat flow and local fluid flow. Multiple slow waves are identified and their relationships with heat and fluid flow mechanisms are analyzed. The study also explores the influence of thermophysical properties on wave velocity and attenuation.
Article
Geochemistry & Geophysics
Guangtan Huang, Jing Ba, Davide Gei, Jose M. Carcione
Summary: This paper introduces the application of fracture-induced azimuthal anisotropy of seismic waves in the characterization of hydrocarbon reservoirs and the overburden. By decoupling the fracture weakness parameters and using the azimuthal amplitude variation with angle/offset inversion, these parameters can be estimated and the fluid can be identified. A novel approximation method is proposed, which incorporates fracture density and fluid indicators.
Article
Geochemistry & Geophysics
Yijun Wei, Jing Ba, Jose M. Carcione
Summary: The elastic properties of rocks depend on various factors, including mineral constituents, pore structure, saturating fluids, and stress conditions. A new acoustoelasticity model has been proposed to study these properties, considering the effects of crack closure and squirt-flow mechanism. The behavior of wave velocity variations in rocks is observed to be dominated by crack properties and then transitioning to acoustoelastic effects as pressure increases.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Juan E. Santos, Jose M. Carcione, Gabriela B. Savioli, Jing Ba
Summary: The study focuses on the attenuation and dispersion mechanisms of P waves in porous media, especially considering the effects of capillary pressure and flow interaction between multiphase fluids on P-wave velocity and dissipation factors.