Article
Energy & Fuels
Bekele Dejene Mulugeta, Yasuhiro Fujimitsu, Jun Nishijima, Hakim Saibi
Summary: The study analyzed the Aluto-Langano geothermal field using gravity data to define the geometry of the geothermal reservoir and subsurface geological structures. The results showed high Bouguer anomalies and geothermal activity in the area, with a 3-D gravity model revealing the presence of a high-density geological body and a geothermal reservoir.
Article
Geosciences, Multidisciplinary
Yuanyuan Niu, Jiancang Zhuang, Ziyao Xiong
Summary: Prior information is often used in geophysical inversions to address the issue of non-uniqueness in the solution. In this study, two methods for calculating the smoothness of Delaunay Tessellation (DT) based interpolators are compared: the double linear interpolation (DLI) method and the newly proposed quadratic interpolation (QI) method. Through numerical experiments and application to a gravity inversion problem, it is found that the QI method performs slightly better than the DLI method.
SPATIAL STATISTICS
(2023)
Article
Energy & Fuels
Jianwei Zhao, Zhaofa Zeng, Shuai Zhou, Jiahe Yan, Baizhou An
Summary: By using the 3-D gravity focusing inversion method, a high-resolution underground spatial density distribution model of the Gonghe Basin was obtained based on satellite gravity data, combined with previous research results including three-dimensional magnetotelluric imaging and linear inversion of Rayleigh wave group and phase velocity result. The results show widely distributed low density anomalies in the middle crust of the study area, which are speculated to be a low-velocity, high-conductivity partial melting layer in the crust of the Gonghe Basin. This high temperature melt layer may be the main heat source of the hot dry rock geothermal resources in the Gonghe Basin, providing a new basis for further research on the genesis of the hot dry rock geothermal system in the Gonghe Basin.
Article
Geosciences, Multidisciplinary
Yongbo Li, Shi Chen, Bei Zhang, Honglei Li
Summary: Residual Bouguer gravity anomaly inversion is used for imaging local density structures or interpreting near-surface anomalous mass distribution. Reasonable prior information is crucial for obtaining realistic geological inversion results, especially for ill-posed geophysical inversion problems. Recent developments in machine learning technology have provided new solutions for geophysical inversion, reducing the need for prior information and significantly reducing the time consumption for inversion.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Environmental Sciences
Klemen Medved, Oleg Odalovic, Bozo Koler
Summary: Slovenia updated its national Bouguer anomaly map, detecting errors in old data and analyzing the influence of new data. The new gravimetric data has a significant impact on the creation of gravitational anomaly maps for Slovenia.
Article
Geochemistry & Geophysics
Rongzhe Zhang, Haoyuan He, Xintong Dong, Tonglin Li, Cai Liu, Xinze Kang
Summary: This study proposes a 3-D gravity data focusing inversion algorithm based on the supervised descent method (SDM) to overcome the limitations of traditional gravity inversion methods. The method shows good potential for improving the accuracy and efficiency of gravity data inversion.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Geochemistry & Geophysics
Lianzhi Zhang, Guibin Zhang, Yao Liu, Zhenyu Fan
Summary: A novel 3-D gravity inversion method based on encoder-decoder neural networks is proposed in this study, which achieves gravity field feature extraction, feature space transformation, and density structure reconstruction. The method improves accuracy and generalizability while reducing computational time.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geosciences, Multidisciplinary
Guiju Wu, Jian Wang, Bingfei Yu, Hongbo Tan, Jiapei Wang, Xinlin Zhang, Zhengbo Zou
Summary: This study uses the NFG method and 3-D gravity inversion to reveal the complex crustal structure beneath the Yinchuan Basin, providing new insights into the geodynamic processes. The results show the complexity of the upper crustal structure and suggest the locations and focal depth of important faults. These findings lay a scientific foundation for studying the crustal dynamics and seismogenic mechanisms of strong earthquakes.
JOURNAL OF ASIAN EARTH SCIENCES
(2022)
Article
Energy & Fuels
Noah D. Athens, Jef K. Caers
Summary: This study investigates the impact of data and model uncertainty on gravity interpretation in geothermal exploration, using a stochastic approach to analyze gravity data from Dixie Valley geothermal field. Sparse data sampling is shown to affect inversion results, with high data density areas showing more consistent results compared to low data density areas. Data uncertainty has a marked impact on depth-to-basement estimates and modeled fault locations, highlighting the importance of considering uncertainty in geothermal exploration modeling.
Article
Geochemistry & Geophysics
Weiyang Liao, Ronghua Peng, Xiangyun Hu, Wenlong Zhou, Guoshu Huang
Summary: This study utilizes a three-dimensional Gauss-Newton approach to jointly invert magnetotelluric (MT) and controlled-source electromagnetic (CSEM) data for better characterization of subsurface resistivity structures. The results of the joint inversion demonstrate improved model characterization for both conductive and resistive structures, which can be applied for exploration and drilling purposes.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Michael S. Zhdanov, Michael Jorgensen, Le Wan
Summary: This novel approach allows for three-dimensional gravity inversion in the presence of a sediment-basement interface with a strong density contrast. It incorporates known information about the basement depth and uses it as a constraint in the inversion process. The results provide a 3D density model of the top layers of the Earth's crust.
Article
Geosciences, Multidisciplinary
Andrea Zunino, Alessandro Ghirotto, Egidio Armadillo, Andreas Fichtner
Summary: This study presents a probabilistic strategy for solving the inverse problem of two-dimensional gravity and magnetic anomaly modeling. It accurately infers possible configurations of geological structures in the subsurface and provides uncertainty estimation.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Jean D'Amour Uwiduhaye, Gaetan Sakindi, Hakim Saibi, Biruk Abera Cherkose
Summary: This study utilized Magnetotelluric (MT) data from the Gisenyi geothermal field in Rwanda to establish a 3D electrical resistivity distribution model for investigating deep geologic structures related to geothermal resources. The analysis revealed a conductive region at deeper depths beneath a high-resistivity zone, with patches of high and low resistivity at shallow depths. The study provides insights into subsurface structures related to the geothermal resource in the area.
JOURNAL OF APPLIED GEOPHYSICS
(2021)
Article
Geochemistry & Geophysics
Boxin Zuo, Xiangyun Hu, Lizhe Wang, Yi Cai, Mason Andrew Kass, Marcelo Leao-Santos
Summary: A novel method based on unstructured tetrahedral grids and partial differential equations framework is proposed for 3-D magnetic numerical forward modeling and inversion, allowing for accurate representation of complex geological structures and improving the capability and accuracy of magnetic data interpretation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Adrian Celaya, Bertrand Denel, Yen Sun, Mauricio Araya-Polo, Antony Price
Summary: This paper introduces two algorithms that can invert simulated gravity data to 3D subsurface rock/flow properties. The first algorithm is a data-driven, deep learning (DL)-based approach, while the second algorithm is also data-driven but considers the temporal evolution of surface gravity events. The target application of these algorithms is the prediction of subsurface CO2 plumes for monitoring CO2 sequestration deployments. Both algorithms outperform traditional inversion methods, producing high-resolution 3D subsurface reconstructions in near real-time. Additionally, the proposed methods achieve high scores for predicted plume geometry and data misfit, indicating the effectiveness of combining 4D surface gravity monitoring with DL techniques for monitoring CO2 storage sites.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Energy & Fuels
Luis Salala, Jonathan Argueta, Noel Lopez, Osmany Aparicio, Diana Martinez, Pedro Santos, Arturo Quezada, Oziel Garcia, Jose Erazo, Hiroyuki Yamagishi, Noriyoshi Tsuchiya
Summary: Geothermal systems have significant potential to replace reliance on fossil fuels. El Salvador, being tectonically active, already supplies a significant portion of its electricity demand using volcanic geothermal fields. The study compares different geothermal areas in El Salvador and highlights the controlling factors in the characteristics of geothermal reservoirs.
Article
Energy & Fuels
Lin Jia, Kewen Li, Yun Han, Chi Zhang, Lipeng Zhao
Summary: This study proposes a new approach of retrofitting abandoned oil wells into geothermal wells, and investigates the effects of different parameters on the performance using a numerical model. The results show that the enhanced fracture system significantly improves the efficiency of geothermal energy extraction, and optimal design should control the flow rate and use proppant.
Article
Energy & Fuels
K. H. Kvalsvik, H. Holmberg, R. K. Ramstad, K. Midttomme
Summary: This study proposes a new analytical equation that takes into account the advective heat in fractured rock, improving the accuracy of measuring thermal properties in borehole heat exchangers. The equation is applicable to all thermal response tests and provides a cost-effective alternative to numerical modelling.
Article
Energy & Fuels
Ronald Dipippo
Summary: This paper presents a technique of further preheating the working fluid in geothermal binary plants using extraction turbines, and evaluates the performance at various geofluid temperatures through working equations. The results indicate that this approach can be equally effective in geothermal binary plants as it is in conventional nuclear power plants.
Article
Energy & Fuels
Y. A. Popov, E. M. Chekhonin, E. G. Savelev, D. A. Ostrizhniy, A. B. Shakirov, R. A. Romushkevich, E. A. Babich, B. E. Andreyev, M. Y. Spasennykh, I. A. Sannikova
Summary: This paper describes the results of experimental geothermal studies on the formation surrounding the Savitskaya-300 well in the Volga-Ural oil and gas basin. The study found high thermal heterogeneity and anisotropy in the formation. The paper provides important data on thermal properties and heat flow variations in the well.
Article
Energy & Fuels
Viren Thakore, Hong Wang, Jy-An Wang, Yarom Polsky, Fei Ren
Summary: This paper focuses on the stability of foam-based fracturing fluid under high temperature and high pressure conditions. It is of significant importance for the development of foam fracturing fluid as an alternative to conventional water-based fracturing fluid in Enhanced Geothermal System (EGS). Experimental results show that with the appropriate selection of surfactants and stabilizing agents, stable foams can be obtained. Analytical models are developed to predict the foam stability for different foam compositions, considering the effects of temperature and pressure.
Article
Energy & Fuels
Hong Chang, Sheng Jiang, Haozhi Jiang, Yunjie Li, Zhengheng Gan, Songying Zhao
Summary: This study compared the bearing performance between phase change energy piles (GPEP) and traditional energy piles (TEP) using indoor modeling tests and theoretical formulas. The results showed that GPEP increased the ultimate bearing capacity of a single pile by about 13% compared to TEP. Additionally, the phase change materials effectively restricted the temperature-drag response of energy piles.
Article
Energy & Fuels
Qiang Zhang, Tiago Alves
Summary: This study investigates the influence of salt structures and faults on the geothermal potential in the Cleaver Bank High, Southern North Sea, using high-quality 3D seismic reflection data and bottom-hole temperature data. The results show that salt structures and faults play a significant role in the geothermal gradient, with higher gradients found on the footwalls of faults. Three potential geothermal exploration targets are identified based on the findings.
Article
Energy & Fuels
Hubert Langevin, Nicolo Giordano, Jasmin Raymond, Louis Gosselin, Martin Bourbonnais
Summary: This study evaluates the efficiency and cost of solar-assisted geothermal systems in a subarctic climate, and offers recommendations for optimizing ground heat exchanger configurations.
Article
Energy & Fuels
Lei Chen, Jinchuan Zhang, Longfei Xu, Shijing Chen, Qianchao Li, Yuhang Sun, Jie Li, Xingxu Zhao
Summary: This study assesses the geothermal water circulation process of a granite geothermal system in the Lancang area, Yunnan using water chemistry and isotope analysis techniques. The results show that the geothermal water originates from atmospheric precipitation and the granite pluton serves as the main heat source. Additionally, the fault system plays an important role in the discharge and mixing of hot and cold water.
Review
Energy & Fuels
Md Azhar, Somenath Mondal, Anh Minh Tang, Akhileshwar K. Singh
Summary: Contemporary geotechnical engineering practice involves the design and construction of structures that encounter thermal cycles. Understanding the effect of temperature on soil mechanical properties is challenging, but there have been significant contributions from numerous studies. However, to date, there is no comprehensive review that provides a holistic development of the subject and its connection to field applications.
Article
Energy & Fuels
Mark White, Yaroslav Vasyliv, Koenraad Beckers, Mario Martinez, Paolo Balestra, Carlo Parisi, Chad Augustine, Gabriela Bran-Anleu, Roland Horne, Laura Pauley, Giorgia Bettin, Theron Marshall, Anastasia Bernat
Summary: The study presents a comprehensive numerical modeling of closed-loop geothermal systems (CLGSs) and develops a publicly accessible web application for feasibility studies. The results suggest that competitive levelized cost of heat (LCOH) can be achieved, but significant reductions in drilling costs are required to achieve competitive levelized cost of electricity (LCOE). A site-based case study for multi-lateral systems and the analysis of permeable wet rock are also provided, indicating the potential for improved power production with higher reservoir permeability and temperature.
Article
Energy & Fuels
Xiaoming Tian, Oleg Volkov, Denis Voskov
Summary: In this study, an efficient and flexible adjoint-based framework is proposed for history matching and forecasting geothermal energy extraction. The framework reduces the parameter space using Principal Component Analysis and speeds up the iteration process using the adjoint method. Operator-based linearization is used for efficient calculation and matrix assembly. The framework is demonstrated to be highly efficient for a heterogeneous reservoir with multiple realizations, generating reliable history-matching results.
Article
Energy & Fuels
Asrillah Asrillah, Agus Abdullah, Klaus Bauer, Ben Norden, Charlotte M. Krawczyk
Summary: At the Gross Scho center dot nebeck geothermal research platform in the NE German Basin, the degree and direction of azimuthal velocity anisotropy caused by sub-vertical fracturing were determined through analysis of 3-D seismic reflection data. The observed anisotropy above the Zechstein salt roughly correlates to fault structures formed by an upwelling salt pillow, while below the salt, the less pronounced anisotropy and interpreted fracturing follow the trend of the regional stress field.
Article
Energy & Fuels
Kyosuke Okamoto, Yusuke Mukuhira, Dian Darisma, Hiroshi Asanuma, Hirokazu Moriya
Summary: Microseismic monitoring is crucial in geothermal development, and manual phase picking for seismic data is time-consuming. Existing deep learning phase pickers may face challenges in geothermal fields due to their unique features. This study focuses on developing a specialized deep learning model for local seismic networks in geothermal fields, allowing automatic hypocenter determinations and revealing subsurface fine structures.