Article
Geosciences, Multidisciplinary
Wenjun Xu, Jinzhou Zhao, Jianguo Xu
Summary: This paper introduces a new Fracability Index (FI) model, which evaluates the potential candidate layers for hydraulic fracturing in unconventional reservoirs by considering the possibilities of complex hydraulic fracture network and large stimulation reservoir volume. The model takes into account essential factors like brittleness, fracture toughness, natural fractures, and in situ stresses, providing a useful tool for selecting the most suitable candidates for fracturing treatments.
NATURAL RESOURCES RESEARCH
(2021)
Article
Energy & Fuels
Qiang Guo, Jing Ba, Cong Luo, Mengqiang Pang
Summary: This study introduces a novel reservoir parameter inversion method for tight sandstone reservoirs, which builds the forward operator to directly invert observed seismic data for reservoir parameters, and iteratively updates pore aspect ratios to address the complex pore structure. By utilizing Bayesian inversion with the prior Gaussian mixture model, the method stabilizes the inversion process and achieves optimal solutions by considering the complex prior distributions of reservoir parameters in different lithofacies.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Energy & Fuels
Mengqiang Pang, Jing Ba, J. M. Carcione, Lin Zhang, Rupeng Ma, Yijun Wei
Summary: This study in a reservoir in the north of the Songliao Basin investigated the microstructure of cores and analyzed their reservoir properties using various methods. The effectiveness of 3D rock-physics templates in estimating the distribution of high-quality tight-oil reservoirs was validated through comparing predicted reservoir properties with well-log data and actual production reports.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Zhiqi Guo, Xiaoying Qin, Cai Liu
Summary: This study proposes a rock-physics-based approach to compute the pore-microfracture indicator (PMI) from elastic properties for pore structure evaluation in tight sandstones. Seismic characterization of pores and microfractures provides valuable information in predicting high-quality tight gas sandstone reservoirs. The computed PMI using seismic data can predict permeable zones and provide valuable information for sweet spot characterization in tight gas sandstone reservoirs.
Article
Geosciences, Multidisciplinary
Mingliyang Cai, Ming Li, Xiaoshuan Zhu, Hao Luo, Qiang Zhang
Summary: This study investigated the rock mechanical properties and in-situ stress characteristics of continental tight oil reservoirs through rock mechanics experiments, acoustic experiments, and finite element simulations. The findings revealed that with increasing confining pressure, tight sandstone samples experience shear ruptures. Additionally, hydraulic fracturing calculations indicated that the in-situ stress state of the target layer meets specific conditions.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Han Jin, Cai Liu, Zhiqi Guo, Yiming Zhang, Cong Niu, Di Wang, Yun Ling
Summary: This study utilized the Chapman theory to simulate the dispersion and attenuation of P-wave velocity in tight gas sandstone. By conducting synthetic seismic AVO modeling, it was found that variations in the amplitudes and phases of the PP reflections can indicate gas saturation in tight sandstone reservoirs. The frequency-dependent AVO inversion method has good potential for evaluating gas saturation in tight gas sandstone reservoirs.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geochemistry & Geophysics
Pu Wang, Yi-an Cui, Jianxin Liu
Summary: Fluid discrimination is challenging for reservoir prediction, especially for tight sandstones. This paper reviews the effective medium models and inversion methods used in seismic exploration and proposes a new inclusion-based rock physics model for tight sandstones. A detailed prediction process for fluid discrimination is given and the effectiveness of the proposed method is demonstrated through field data applications.
SURVEYS IN GEOPHYSICS
(2022)
Article
Geochemistry & Geophysics
Jing Ba, Peng Hu, Wenhui Tan, Tobias M. Muller, Li-Yun Fu
Summary: The study conducted ultrasonic experiments on reservoir rocks from Chang-7 member of Yanchang Formation in Ordos Basin and proposed a method for predicting brittleness based on rock physics model, which is of great significance for oil production. The brittleness mineral analysis was performed using data from multiple scales, and the model accuracy was verified by experimental and seismic data. Ultimately, the brittleness distribution was predicted based on log and seismic data, providing guidance for actual engineering operations.
JOURNAL OF GEOPHYSICS AND ENGINEERING
(2021)
Article
Geosciences, Multidisciplinary
Rupeng Ma, Jing Ba, Jose Carcione, Maxim Lebedev, Changsheng Wang
Summary: The petrophysical properties are important indicators for identifying oil and gas reservoirs. Ultrasonic measurements show that properties with high fluid-sensitivity indicators can successfully distinguish between gas, oil, and water, while siltstones and dolomites can be identified based on data distribution areas.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Yuangui Zhang, Bangrang Di, Feng Gao, Lei Li
Summary: Background porosity has a significant influence on seismic anisotropy and shear wave splitting in fractures. The experimental results show that increasing porosity leads to a decrease in P-wave anisotropy, while shear wave splitting remains nearly constant. These results are consistent with predictions from equivalent medium theories.
APPLIED SCIENCES-BASEL
(2023)
Article
Geochemistry & Geophysics
Xiong Liu, Desheng Zhou, Le Yan, Shun Liu, Yafei Liu
Summary: A model suitable for evaluating a tight sandstone reservoir is established, considering the influence of capillary force, osmotic pressure, production pressure difference, and starting pressure gradient on oil-water replacement rate. Results show that higher relative permeability of water phase, lower relative permeability of oil phase, smaller oil-water viscosity ratio lead to higher oil-water replacement rate.
Article
Environmental Sciences
Yunpu Yang, Lijun Ma, Zhonghui Yao, Yan Feng
Summary: This paper calculates the brittleness indexes of Upper Paleozoic tight sandstone reservoirs in the eastern Ordos Basin using the gray correlation and rock mineral composition methods and analyzes the influence of mineral composition on the brittleness index. The results show that quartz component has a positive correlation with rock porosity, while the relationship between feldspar content and rock porosity is more complicated.
FRESENIUS ENVIRONMENTAL BULLETIN
(2022)
Article
Energy & Fuels
Han Jin, Cai Liu, Zhiqi Guo
Summary: In this study, a seismic inversion method combined with rock physical modeling is developed to directly predict the lithology and pore structure in tight formations. The results from real data applications demonstrate that the proposed method is applicable for the effective characterization of tight gas sandstones.
Article
Geosciences, Multidisciplinary
Jinghuai Gao, Weimin Han, Yanbin He, Haixia Zhao, Hui Li, Yijie Zhang, Zongben Xu
Summary: This paper focuses on deriving wave equations in tight oil/gas media, which have a simpler form and can be used for parameter inversion. The derived equations are validated by numerical results and further investigation on the reflection and transmission properties of tight interlayers is conducted.
SCIENCE CHINA-EARTH SCIENCES
(2021)
Article
Geosciences, Multidisciplinary
Martin Balcewicz, Mirko Siegert, Marcel Gurris, Matthias Ruf, David Krach, Holger Steeb, Erik H. Saenger
Summary: Digital Rock Physics (DRP) has become an integral part of reservoir characterization in the past 30 years due to its non-destructive testing nature. High-resolution X-ray Computed Tomography (XRCT) technology allows for precise imaging of material particles in volume. However, assigning physical properties to specific voxels within the digital twin remains a challenge, requiring a combination of various imaging techniques and geological input properties for optimal spatial segmentation.
FRONTIERS IN EARTH SCIENCE
(2021)
