| Title | Effect of Water Saturation on Gas-Accessible Effective Pore Space in Gas Shales |
| Authors | Chen, Lei Liu, Keyu Xu, Liangwei Jiang, Shu Fu, Yonghong Tan, Jingqiang Fan, Yuchen |
| Affiliation | China Univ Petr East China, Shandong Prov Key Lab Deep Oil & Gas, Qingdao 266580, Peoples R China China Univ Petr East China, Sch Geosci, Qingdao 266580, Peoples R China Univ Utah, Energy Geosci Inst, Salt Lake City, UT 84108 USA Peking Univ, Sch Earth & Space Sci, Beijing 100871, Peoples R China China Univ Geosci, Key Lab Tecton & Petr Resources, Minist Educ, Wuhan 430074, Peoples R China Southwest Petr Univ, Sch Geosci & Technol, Chengdu 610500, Peoples R China Cent South Univ, Sch Geosci & Info Phys, Changsha 410012, Peoples R China |
| Keywords | SOUTHERN SICHUAN BASIN ORGANIC-RICH SHALES METHANE ADSORPTION BARNETT SHALE NMR BEHAVIOR SYSTEMS PERMEABILITY HAYNESVILLE EVOLUTION |
| Issue Date | 7-Jul-2022 |
| Publisher | LITHOSPHERE |
| Abstract | The existence and content of water will certainly affect the effective pore space of shales and therefore is a key point for the evaluation of in-situ gas content and gas flow capacity of shale reservoirs. In order to reasonably evaluate the gas storage and flow capacities of water-bearing shale reservoirs, the effect of water on the effective pore space of shales needs to be understood. In this study, the Upper Permian Longtan shale in the southeastern Sichuan Basin, China, was selected as an example to conduct nuclear magnetic resonance cryoporometry (NMRC) measurements under different water saturation levels. The gas-accessible effective pore spaces in shales under different water saturation levels were quantified, and the effect of water saturation on gas-accessible effective pore space in shales was investigated. The results show that water plays an important role in the gas-accessible effective pore space of shales. When the Longtan shale increases from a dry state to a water saturation of 65%, 75%, and 90%, the gas-accessible effective pore volume decreases by 35%-60% (average 46.3%), 50%-70% (average 58.8%), and 65%-82% (average 75.8%), respectively. Water has an effect on the gas-accessible effective pore space regardless of pore size, and the effect is the strongest in the 4-100nm range, which may be mainly due to the high content of clay minerals in the Longtan shale. Our studies are of important theoretical significance and application prospects for accurately evaluating the gas-accessible effective pore space of gas shales under actual geological conditions. |
| URI | http://hdl.handle.net/20.500.11897/669376 |
| ISSN | 1941-8264 |
| DOI | 10.2113/2022/1939833 |
| Indexed | SCI(E) |
| Appears in Collections: | 地球与空间科学学院 |
