Article
Geosciences, Multidisciplinary
Leilei Yang, Longfei Lu, Xiaowei Li, Yansheng Shan, Chenchen Mo, Meng Sun, Jing Hu, Weibin Liu, Baoxing Liang, Jin Xu
Summary: This study investigates the transformation of diagenetic minerals in shale reservoirs in the Da'anzhai Member of the Sichuan Basin. The results show that temperature, pressure, fluid, and lithology are the main factors affecting the transformation, and organic acids play an important role in the conversion in K-rich fluids. These findings provide valuable theoretical support for understanding the diagenesis and formation mechanism of shale reservoirs and for the efficient exploration and development of shale gas.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geochemistry & Geophysics
Yixiu Zhu, Zezhou Li, Lianbo Zeng, Zhenyu Liu, Xinyao Wang
Summary: This paper describes the characteristics of lacustrine fine-grained rock reservoir in the Da'anzhai Member of the Ziliujing Formation in the Sichuan Basin, and discusses the impact of diagenesis on the reservoir quality. The study identifies compaction and cementation as the main factors controlling the physical properties of shale and limestone, and the difference between dissolution and cementation as the main control factor for the formation of different reservoir types.
Article
Energy & Fuels
Rui Zhang, Longxiang Tang
Summary: This study analyzed the oil-bearing characteristics and reservoir physical properties of different lithofacies in the Jurassic Da'anzhai Member. The results showed that shale has better oil-bearing and physical properties compared to shell limestone and peperite. The thick shale of the Da2b layer has the highest potential for shale oil exploration and development.
PETROLEUM SCIENCE AND TECHNOLOGY
(2023)
Article
Energy & Fuels
Peng Yang, Likuan Zhang, Keyu Liu, Binfeng Cao, Jianlei Gao, Guiqiang Qiu
Summary: The second member of the Upper Triassic Xujiahe Formation in the western Sichuan Basin is targeted for tight gas exploration, with poor reservoir properties characterized by low porosity and permeability. The diagenetic evolution includes mechanical and chemical compaction, quartz overgrowths, cementation, dissolution of feldspar, and precipitation of various minerals. Sandstone lithofacies are defined based on texture, composition, diagenetic minerals, and pore types, with lithofacies I showing the best reservoir properties and potential as high-quality reservoir facies in tight sandstone reservoirs.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Chemical
Yang Wang, Yu Fan, Song Li, Zefei Lv, Rui He, Liang Wang
Summary: China's argillaceous limestone reservoir is rich in oil and gas resources, but faces numerous difficulties in hydraulic fracturing. This paper addresses issues such as reservoir heterogeneity, fluid loss, closure pressure, and proppant migration, and establishes optimal fracturing parameters and ceramic particle mixtures. The research achieves favorable stimulation effects with significant increases in daily oil production and fracture length.
Article
Energy & Fuels
Song Li, Yu Fan, Yang Wang, Yuanshou Zhao, Zefei Lv, Zeng Ji, Weihua Chen, Jian Min
Summary: This article introduces the research experiments on volumetric fracturing technology in the limestone reservoir of the Da'anzhai section in central Sichuan. The results of the experiments show that low stress differences, natural fracture development, and low viscosity slippery water are favorable factors for obtaining complex fracture morphology. By optimizing geological description and implementing targeted technological measures, bulk fracturing has been proven to be feasible in the dense limestone reservoir of the Da'anzhai section.
FRONTIERS IN ENERGY RESEARCH
(2023)
Article
Energy & Fuels
Su Chengpeng, Li Rong, Shi Guoshan, Jia Huofu, Song Xiaobo
Summary: Based on field observations and core samples, the reservoir characteristics of the first member of Middle Permian Maokou Formation in the Sichuan Basin were analyzed, revealing a tight carbonate fracture-pore type reservoir with low porosity and permeability. The presence of different clay minerals in the reservoir indicates significant regional variations, with potential sweet spots for high production in the southwestern inner ramp and large contiguous reservoirs with lower production in the eastern outer ramp.
PETROLEUM EXPLORATION AND DEVELOPMENT
(2021)
Article
Geosciences, Multidisciplinary
Qianwen Li, Zhongbao Liu, Feiran Chen, Guangxiang Liu, Dianwei Zhang, Peng Li, Pengwei Wang
Summary: Comprehensive analysis of the Jurassic Da'anzhai Member shale strata in the northeastern Sichuan Basin reveals the organic geochemical characteristics, organic matter provenance, and sedimentary environment. The J(1)da(2) section is identified as the most favorable for hydrocarbon enrichment. The organic matters in the J(1)da shale strata are derived from both terrestrial higher plants and lower aquatic organisms, suggesting a freshwater lacustrine environment overall.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Energy & Fuels
Tianqi Zhou, Chaodong Wu, Xutong Guan, Jialin Wang, Wen Zhu, Bo Yuan
Summary: The study focused on the diagenesis and hydrocarbon charging impact on sandstone reservoir-forming process in Toutunhe Formation. Three diagenetic facies were identified, with only one hydrocarbon emplacing event occurring between 13-8 Ma. Burial pattern and reservoir wettability changes were found to be major controlling factors, influencing oil and gas enrichment.
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
Daiqin Jiang, Pingping Li, Mingjun Zheng, Quan Chen, Wenting Xiong, Huayao Zou
Summary: This study investigates the pore structure characteristics of Da'anzhai shale using various measurement techniques and discusses the impact of different matrix components on the pore structure and reservoir capacity. The results show that the pore system of Da'anzhai shale is composed of mineral-associated pores, organic matter pores, and microfractures. Clay-mineral pores dominate, followed by organic matter pores. The controlling factors of the pore structure are TOC, organic macerals, and clay minerals. This study provides a better understanding of the pore formation mechanism of shale reservoirs, which is significant for gas-bearing evaluations.
Article
Energy & Fuels
Qi-Lu Xu, Bo Liu, Xin-Min Song, Qing-Ping Wang, Xu-Dong Chen, Yang Li, Yu Zhang
Summary: The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. Lacustrine limestone has a higher organic matter conversion rate and a lower hydrocarbon generation threshold than argillaceous source rocks, and can be an effective source rock.
Article
Multidisciplinary Sciences
Jie Tian, Hongqi Liu, Liang Wang, Liqiang Sima, Shiqiong Liu, Xiangjun Liu
Summary: The Da'anzhai Member of the Jurassic Ziliujing formation in central Sichuan is a typical tight-oil reservoir with well-developed fractures in micro- and nano-scale. The study found that the microscopic composition of shelly grains and calcite grains separately control the development of different types of fractures, and established a method to predict fracture characteristics in tight-oil reservoirs using well-logs.
SCIENTIFIC REPORTS
(2021)
Article
Geochemistry & Geophysics
Xianfeng Liu, Yilin Liang, Jinbao Duan, Yanping Luo
Summary: The Maokou Formation in the Sichuan Basin has the potential to become a new field for oil and gas exploration. The Eyeball-shaped limestone in the Maokou Formation has a different hydrocarbon enrichment pattern compared to conventional unconventional shale gas reservoirs and conventional carbonate reservoirs.
Article
Geosciences, Multidisciplinary
Yao Du, Xingzhi Wang, Rongrong Zhao, Chi Chen, Siying Wen, Ruifeng Tang, Qianwen Mo, Jizhi Zhang, Yu Zhang, Shuo He
Summary: This study analyzed the relationship between sedimentary environment and organic matter enrichment of continental shale through petrology and organic and inorganic geochemistry tests of 153 samples. The results showed that different lithologic associations have different contents of organic matter and different paleoenvironmental factors play different leading roles in organic matter enrichment.
FRONTIERS IN EARTH SCIENCE
(2022)