Advances in low-field nuclear magnetic resonance (NMR) technologies applied for characterization of

• 作 者: Jian-Chun Guo Hang-Yu Zhou Jie Zeng Kun-Jie Wang Jie Lai Yu-Xuan Liu
• 机 构: State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum Universit
• 出 处: 石油科学（英文版）
• 发表日期: 2020年5期
• 关键词: Low-field NMR Critical review Relaxation theory Unconventional formation

NMR serves as an important technique for probing rock pore space,such as pore structure characterization,fluid identification,and petrophysical property testing,due to the reusability of cores,convenience in sample processing,and time efficiency in laboratory tests.In practice,NMR signal collection is normally achieved through polarized nuclei relaxation which releases crucial relaxation messages for result interpretation.The impetus of this work is to help engineers and researchers with petroleum background obtain new insights into NMR principals and extend existing methodologies for characterization of unconventional formations.This article first gives a brief description of the development history of relaxation theories and models for porous media.Then,the widely used NMR techniques for characterizing petrophysical properties and pore structures are presented.Meanwhile,limitations and deficiencies of them are summarized.Finally,future work on improving these insufficiencies and approaches of enhancement applicability for NMR technologies are discussed.