Article
Engineering, Marine
Yijie Chen, Zhenwei Guo, Dawei Gao
Summary: The marine controlled-source electromagnetic (CSEM) method is an efficient tool for hydrocarbon exploration. However, the signal quality is easily affected by various types of noise due to the rapid decay of signal amplitudes with increasing offset. In this study, we introduced a new method called symplectic geometry mode decomposition (SGMD) to improve the data quality of marine CSEM by reducing noise. The experiments showed that SGMD outperformed other methods like variational mode decomposition and the sym4 wavelet method.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Geochemistry & Geophysics
Amir Rostami, Noorhana Yahaya, Hassan Soleimani, Muhammad Rauf, Tadiwa E. Nyamasvisva, Afza Shafie, Vahid Khosravi, Menaka Ganeson
Summary: Controlled-source electromagnetics is an efficient technique for exploring deep-water marine hydrocarbon reservoirs, but shallow-water limitations still exist. This work modifies the electromagnetic source to disperse the airwave in shallow water, leading to a better performance in oil delineation compared to conventional methods. Modifications to balance the up-down signals could enhance the target signal delineation magnitude, potentially improving oil detection capability.
JOURNAL OF GEOPHYSICS AND ENGINEERING
(2021)
Article
Engineering, Marine
Yuan Li, Evert Slob, Dieter Werthmuller, Lipeng Wang, Hailong Lu
Summary: Natural gas hydrates have been recognized as an unconventional energy source in recent decades. Marine electromagnetic methods, specifically the classification of acquisition configurations, have been successfully employed to detect their presence. Stationary configurations provide useful data for estimating the boundaries of gas hydrate reservoirs buried beneath the seafloor. CSEM has proven to be a reliable method for decision-making in gas hydrate reservoir appraisal and development.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Geochemistry & Geophysics
Hanbo Chen, Bin Xiong, Yuguo Lu, Qiyun Jiang, Lishan Huang, Shuai Zhou
Summary: In this article, a high-precision forward algorithm for 3-D modeling for MCSEM is proposed, which uses unstructured meshes and local mesh refinement techniques for simulating complex terrains and targets. The application of electric dipole discrete technology enables more realistic electromagnetic field distribution. Absorption boundary conditions and the open-source MUMPS solver are introduced to improve accuracy and efficiency. The proposed algorithm is validated with typical geoelectric models.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Geochemistry & Geophysics
Pengfei Zhang, Xinpeng Pan, Jiawei Liu
Summary: This article proposes a dictionary-learning-based denoising method for marine CSEM, which improves data quality by sparsely representing and reconstructing the contaminated signal. The effectiveness and superiority of the method are demonstrated through experiments.
Article
Geochemistry & Geophysics
Ming Zhang, Colin G. Farquharson, Changsheng Liu
Summary: The paper introduces an improved method for apparent resistivity pseudo-sections to better recognize boundaries. Using an appropriate transmitter-receiver distance can lead to clear identification of vertical boundaries and top and bottom boundaries.
GEOPHYSICAL PROSPECTING
(2021)
Article
Geosciences, Multidisciplinary
Rui Yang, Xuben Wang, Meng Wang, Xianhu Luo, Ming Deng, Jianen Jing, Kai Chen
Summary: The marine controlled-source electromagnetic (MCSEM) method is widely used in gas hydrate exploration. In order to obtain a potential real-time imaging method, a rapid imaging technique for the deployed transmission system has been developed, which can qualitatively identify reservoirs in the apparent resistivity pseudosections by replacing current and electromagnetic field data with rotational invariants and using an approximate formula.
JOURNAL OF APPLIED GEOPHYSICS
(2023)
Article
Engineering, Aerospace
Aaron B. Vaughn, Kent L. Gee, S. Hales Swift, Kevin M. Leete, Alan T. Wall, J. Micah Downing, Michael M. James
Summary: The study investigates the apparent source locations of crackle perception in the noise field of a high-performance military jet aircraft, showing that crackle-related events may be generated by Mach wave radiation and large-scale turbulence structure noise. The propagation angle, derivative skewness, and overall sound pressure level of shock events play a key role in determining the location of crackle generation.
Article
Geochemistry & Geophysics
M. Weiss, T. Kalscheuer, Z. Ren
Summary: This paper presents a parallel spectral element approach for forward modelling of realistic 3-D land-based controlled-source electromagnetic problems. The method combines the flexibility of the finite element method in using unstructured grids with the accuracy of the spectral method. Complex-shaped structures and topography can be accommodated by using unstructured hexahedral meshes. The method allows for arbitrary distributions of conductivity, magnetic permeability and dielectric permittivity. Numerical examples and convergence studies demonstrate the advantages and trade-offs of the method in terms of computational resources and accuracy.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Yi Zhang, Chunying Gu, Jiayu Yang, Suyi Li
Summary: “”The MVO curve is commonly used to identify electromagnetic anomalies in oil and gas reservoirs. However, it can be challenging to identify high resistance anomalies when multiple emission frequencies are present. In addition, noise reduces the accuracy of manual detection. This paper proposes using bidirectional LSTM to solve the problem of anomaly identification in marine controlled-source electromagnetic data. Different LSTM models were trained and tested, and the bidirectional LSTM model showed the best accuracy, reaching 100% in theoretical data and 79.58% in synthetic noise data.
EXPLORATION GEOPHYSICS
(2023)
Article
Geochemistry & Geophysics
Keiichi Ishizu, Weerachai Siripunvaraporn, Tada-nori Goto, Katsuaki Koike, Takafumi Kasaya, Hisanori Iwamoto
Summary: This study presents a cost-effective 3D marine controlled-source electromagnetic (CSEM) survey method for exploring seafloor massive sulfides (SMS). By using fewer receivers and a line configuration, the survey reduces costs while accurately mapping SMS.
Article
Computer Science, Interdisciplinary Applications
Yat Tin Chow, Fuqun Han, Jun Zou
Summary: In this work, a novel direct sampling method (DSM) is proposed to simultaneously recover the support of two different types of electromagnetic inhomogeneous inclusions using only one or two sets of noisy boundary measurement data. The DSM leverages an almost orthogonality property between the fundamental solutions of the forward problem and proper families of probing functions. Two families of probing functions are introduced to accurately reconstruct the support of inhomogeneous inclusions in parallel and perpendicular directions to the measurement surface. The DSM is computationally efficient, effective with limited measurement data, and robust against reasonable levels of random noise, as demonstrated by extensive numerical experiments.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Mathematics, Applied
Yueyuan Gao, Natsuhiko Yoshinaga
Summary: We investigate crack propagation in an inhomogeneous media using phase-field models. Simulations based on two different surface energy functionals demonstrate that the J-integral reflects the effective inhomogeneous toughness. Furthermore, we propose a regression method to estimate space-dependent fracture toughness from the crack path, which successfully identifies the positions and magnitude of tougher regions, and works for different geometries of inhomogeneity.
PHYSICA D-NONLINEAR PHENOMENA
(2023)
Article
Chemistry, Multidisciplinary
Bin Xiong, Yuguo Lu, Hanbo Chen, Ziyu Cheng, Hao Liu, Yu Han
Summary: This study proposes a new algorithm for a higher-order vector finite element method, which uses two new types of second-order edge elements to solve the electromagnetic field diffusion problem in a 3D anisotropic medium. The algorithm reduces the number of unknowns compared to the traditional quadratic element and demonstrates the same level of accuracy while offering a significant advantage in terms of computational cost.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Electrical & Electronic
Il-Suek Koh
Summary: This article investigates the representation of the dyadic Green's function when an infinitesimal electric dipole and an observation point are located above an infinite planar dielectric interface. A concise and efficient expression is obtained through mathematical transformations and approximations, which is then numerically verified. Analytical evaluations of electric field components are also conducted when both the source point and observation point are on the interface.
IET MICROWAVES ANTENNAS & PROPAGATION
(2022)
Article
Engineering, Multidisciplinary
Yuri G. Soloveichik, Marina G. Persova, Alexander M. Grif, Anastasia S. Ovchinnikova, Ilya I. Patrushev, Denis V. Vagin, Dmitry S. Kiselev
Summary: This paper proposes a model and numerical method for simulating multiphase multicomponent flow in porous media for hydrocarbon reservoir engineering. The method takes into account the complex structure of reservoirs, operating wells, and various properties of phases. It provides computational efficiency, local mass conservation, and maintains the constraint of phase saturations. The effectiveness of the method is demonstrated through verification and comparison with experimental results.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Physics, Fluids & Plasmas
V. B. Yassinskiy, Yu A. Kuznetsova, S. M. Korobeynikov, D. V. Vagin
Summary: The analysis of electrooptical measurements using the Kerr effect revealed the intensity of the initiation field of the anode streamer at the prebreakdown stage of an electric discharge in water. By conducting computer simulations in a point-to-plane system near the anode tip, the distribution of electric field strength and phase difference was determined. It was discovered that accounting for the nonlinearity of relative permittivity and saturation of polarization increased the field strength near the needle tip and compressed both the strong field region and Kerr fringes. These factors explained the unusual shape of the chronogram and estimated the field strength of the anode streamer appearance to be approximately 40-50 MV/cm.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Marina G. Persova, Yuri G. Soloveichik, George M. Trigubovich, Denis V. Vagin, Alexander M. Grif, Dmitry S. Kiselev, Anastasia P. Sivenkova
Summary: We propose an approach to solve the 3-D inverse problems of airborne time-domain electromagnetic (TD-EM) survey in complex geoelectrical conditions. The geoelectrical model of the geological medium is parameterized using global and local structures, and different types of parameters are used to characterize it. Regularizing terms are employed in the inversion process to control the self-crossing of geometric boundaries and extend the physical parameters. By conducting the inversion in two stages and using local block structures, the position and type of 3-D inhomogeneities under the overburdens can be accurately determined.
JOURNAL OF APPLIED GEOPHYSICS
(2022)
Article
Geochemistry & Geophysics
Marina G. Persova, Yuri G. Soloveichik, Denis V. Vagin, Anastasia P. Sivenkova, Anna S. Kiseleva, Dmitry S. Kiselev, Marina G. Tokareva
Summary: This article presents two approaches for solving airborne electromagnetic problems considering the induced polarization effect - calculating the field directly in the time domain and calculating the EM+IP field in the frequency domain. Both methods allow modeling complex media with topography and 3D heterogeneities, and the results are compared with those of other researchers.
JOURNAL OF ENVIRONMENTAL AND ENGINEERING GEOPHYSICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Yuri G. Soloveichik, Marina G. Persova, Petr A. Domnikov, Yulia I. Koshkina, Dmitry S. Kiselev, Anna S. Kiseleva
Summary: This paper proposes an iterative solver for large sparse systems of linear algebraic equations, which achieves higher accuracy and lower computational time compared to other methods.
COMPUTERS & GEOSCIENCES
(2022)
Article
Engineering, Electrical & Electronic
Marina N. Lyutikova, Sergey M. Korobeynikov, Alexander V. Ridel, Denis V. Vagin, Alexander A. Konovalov
Summary: This study examines the relationship between the insulating properties of oil in high voltage oil-filled equipment and temperature. It is found that ice crystals and water bridges may form during the cooling process, and the cooling method and degree of oil oxidation can affect the breakdown voltage.
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
(2022)
Article
Geosciences, Multidisciplinary
Marina G. Persova, Yuri G. Soloveichik, Jostein K. Kjerstad, Anastasia P. Sivenkova, Anna S. Kiseleva, Dmitry S. Kiselev
Summary: To solve the problem of detecting and delineating marine hydrocarbon deposits, we propose a 2.5D inversion method for electromagnetic data using a differentially normalized method of electrical prospecting. This method parameterizes the geological medium using block structures and takes into account bathymetry as a 3D surface. By minimizing a functional, the coordinates of block boundaries and conductivity inside blocks and layers are determined. The proposed approach is validated through field data inversion in the North Sea, where target bodies are confirmed by well data.
JOURNAL OF APPLIED GEOPHYSICS
(2023)
Article
Engineering, Petroleum
L. M. Gaisina, I. L. Litvinenko, L. R. Magomaeva, A. A. Agayev
Summary: The article examines the impact of the pandemic and the green economy on the development of the oil and gas industry, identifying trends and changes in the sector. It also studies the forecasts and risks associated with the development of the industry in the context of the pandemic and the green economy. The article explores the strategic prospects for the industry as an alternative to the green economy and analyzes the geographic features of the energy transformation.
