Article
Geochemistry & Geophysics
Yongchao Xue, Qingshuang Jin, Hua Tian
Summary: This paper focuses on a typical tight sandstone gas reservoir in Changqing Oilfield, revealing a strong stress sensitivity and impact of start-up pressure gradient on gas well productivity.
Article
Energy & Fuels
Jie He, Xiangdong Guo, Hongjun Cui, Kaiyu Lei, Yanyun Lei, Lin Zhou, Qinghai Liu, Yushuang Zhu, Linyu Liu
Summary: The study shows that changes in gas viscosity and compressibility with pressure and temperature affect the results in the modified flowing material balance method. When allocating dynamic reserves, it has an important impact on the stable production period and initial decline rate.
Article
Engineering, Geological
Ying Xu, Junjie Xiao, Xing Li, Kaiwen Xia, Jianbing Peng
Summary: Coupled thermal-hydraulic-mechanical triaxial flow-through tests were conducted to investigate the effect of elevated temperatures on the permeability evolution and stress sensitivity of a typical argillaceous sandstone from Zhongjiang Gas field in the Sichuan Basin, China. Experimental results showed that the initial permeability gradually decreased with increasing temperature, with a magnitude of up to 1.5 orders. Stress sensitivity was negatively correlated with temperature levels. The permeability reduction was mainly caused by thermal expansion of illite and pore-filling and throat-clogging effects.
ENGINEERING GEOLOGY
(2023)
Article
Energy & Fuels
Jun Wang, Jiahui Du, Wenpu Li, Xianhui Chen, Huan Zhang, Tao Wang, Zhu Li, Ruiqing Hao
Summary: This paper analyzes different brittleness indices, proposes a new index, and conducts experiments to validate its effectiveness. The results show that the newly proposed index can accurately assess the brittle evolution of rocks under different conditions, and investigate the relationship between rock brittleness and confining and gas pressures. This has important implications for practical engineering.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Engineering, Chemical
Liangbin Dou, Xiongdi Zuo, Le Qu, Yingjian Xiao, Gang Bi, Rui Wang, Ming Zhang
Summary: This paper studied the fracability of tight sandstone reservoirs using a new model that incorporates geomechanics properties and in situ stresses. The new model accurately evaluates the fracability of reservoirs and has a high correlation with production history.
Article
Geosciences, Multidisciplinary
Shuizhen Liu, Jianwei Feng, Josephine Anima Osafo, Guisheng Li, Gang Li
Summary: In this research, a novel geomechanical model was established to predict fractures in ultra-deep reservoirs. By combining the minimum energy dissipation principle, the generalized Hooke's law, and the three-shear energy yield criterion, a constitutive model and failure criterion for rocks were derived. The stress-energy coupling characterization model of fracture density parameter was obtained based on the law of conservation of energy. The model was validated by simulating the distributions of tectonic stress field and fractures in the Keshen anticline.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Physics, Multidisciplinary
Weitao Wu, Xinshan Wei, Xiaohui Zhao, Ning Li, Xiang Lu, Jiawei Chen
Summary: This study determines the controlling factors of gas-bearing properties of tight sandstone in the Sulige Gas Field, based on sealing coring, logging, drilling, gas testing, and laboratory analysis. The distribution of gas saturation shows a downward trend from bottom to top, controlled by factors such as source rock properties and reservoir physical properties. Different gas-bearing patterns can be observed based on the distribution of reservoir and source rock conditions.
FRONTIERS IN PHYSICS
(2022)
Article
Energy & Fuels
Xiangdong Guo, Min Lv, Hongjun Cui, Kaiyu Lei, Yanyun Lei, Yushuang Zhu
Summary: Based on static geology and dynamic production, this study establishes a convenient method for evaluating the controlled reserves of wells in Yan'an gas field. By applying the method to 88 wells, the productivity and parameter characteristics of the wells are evaluated. The modified flow material balance method is more accurate and applicable. This study provides a new method for evaluating the controlled reserves of tight gas sandstone wells and offers reference values for other evaluating methods.
JOURNAL OF PETROLEUM EXPLORATION AND PRODUCTION TECHNOLOGY
(2023)
Article
Energy & Fuels
Jing-Dong Liu, Cun-Jian Zhang, You-Lu Jiang, Guo-Shuai Bai
Summary: This paper presents a method for evaluating overpressure and its effect on natural gas charging in tight sandstone in a compressional basin using the example of the Xujiahe Formation in the northeastern Sichuan Basin. The study reveals that hydrocarbon generation and tectonic compression are the main causes of overpressure. The residual pressure difference between the source rocks and reservoir is the major driving force for tight sandstone gas charging. The research provides important insights into evaluating overpressure and pressure difference, as well as investigating natural gas charging space in compressed basins.
Article
Energy & Fuels
Dongjin Xu, Shihai Chen, Jinfeng Chen, Jinshan Xue, Huan Yang
Summary: The study shows that in hydraulic fracturing operations, fracturing fluid starts to infiltrate from the contact surface between the formation and the fluid, leading to formation damage at different depths over time. Sandstone cores with low permeability are more susceptible to damage compared to high-permeability cores, due to their stronger capability of retaining fracturing fluid.
Article
Geosciences, Multidisciplinary
Ziyi Wang, Nengwu Zhou, Shuangfang Lu, Yancheng Liu, Liming Lin, Yang Liu, Bo Song
Summary: This study investigates the generation, accumulation, and distribution of tight sandstone gas in the Linxing-Shenfu gas fields in the northeastern margin of the Ordos Basin. It utilizes various approaches and data analysis to characterize different types of reservoirs and their formation mechanisms.
MARINE AND PETROLEUM GEOLOGY
(2023)
Review
Green & Sustainable Science & Technology
Minhua Cheng, Wen Xue, Zhi Guo, Meifang Hou, Chenhui Wang
Summary: The geological characteristics of tight gas sandstone reservoirs in the Sulige gas field in the Ordos Basin are summarized, and the challenges and recommendations for the development of the reservoirs are discussed in order to enhance the stable production time of the gas field. The results show that the reservoir properties of tight sandstone gas reservoirs in the Sulige gas field exhibit strong heterogeneity, and increasing the well density in the enrichment area can significantly improve the recovery rate. To achieve long-term stable production, it is necessary to improve the reservoir description technology and implement measures such as replenishing fractures, sidetracking horizontal wells, and re-fracturing.
Article
Energy & Fuels
Hao Shi, Fengpeng Lai, Gongshuai Shi, Yisheng Liang, Yuting Dai
Summary: The study investigates the impact of multiphase flow on bottomhole-pressure estimation and productivity forecast for tight gas wells. The modified Beggs-Brill method shows high accuracy in BHP calculation, and a new productivity model integrating the water blockage effect is validated. Results also reveal a power-law relationship between gas relative permeability, gas-water mass ratio, and gas productivity reduction in water-blockage areas for tight gas wells.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Mechanical
Tianjun Zhang, Xiang Ji, Mingkun Pang, Lei Zhang, Bing Ji, Wen Yang, Hongyu Pan
Summary: The crack evolution characteristics of coal and rock bodies around boreholes were studied using the digital speckle correlation method. Various parameters such as stress threshold, surface deformation field, crack opening and shear, and strain energy density were quantitatively analyzed. The results revealed that the distribution of surface cracks is influenced by the borehole structure and grouting. In the later stages, cracks continue to open and shear, leading to specimen damage. The presence of cohesion reduces the tensile stress intensity factor of cracks, facilitating their connection and penetration.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Energy & Fuels
Steffen Nolte, Reinhard Fink, Bernhard M. Krooss, Ralf Littke
Summary: Gas transport processes in low-permeable sandstones at elevated pore pressures involve a combination of fluid-dynamic and rock-mechanical stress effects. Permeability experiments with gas and volumetric strain measurements were used to assess the interdependency of both processes. The results showed that the modified effective stress laws and a clay-shell pore structure model were effective in describing the interrelated changes in permeability and bulk volume with respect to pore and confining pressure.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)