测井技术2011，Vol.35Issue(2)：130-136,7.
气水模型(T2,D)二维核磁共振测井数值模拟及参数影响分析
Inversion Simulation of (T2 ,D) 2D NMR Logging and Analysis of Observation Parameters Effects in Gas-water Model
摘要
Abstract
One-dimension Nuclear Magnetic Resonance (1D NMR) logging technology is limited in some reservoirs. However, two-dimension Nuclear Magnetic Resonance (2D NMR) not only can give accurate porosity, but also is more advantageous in fluid typing than 1D NMR. First,according to the relaxation mechanism of (T2 ,D) 2D NMR in gradient field, an improved truncated singular value decomposition (TSVD) method is used to realize two-dimension spectrum inversion with diverse gas-bearing models. Then, point to gas saturation models, forward modeling and inversion tests are implemented in detail with different acquisition parameters such as different echo spacing (TE) groups, different magnetic field gradients (G) and different signal to noise ratio (SNR), and the influences of observation parameters above on the inversion accuracy is investigated and analyzed. When the magnetic field gradient (G) is around 3.0 × 103 T/crm in multi-TE activation, the observation and inversion effects are both more suitable, and the observation results and inversion effects of hybrid echo spacing group with long echo spacing and short echo spacing are best in same waiting time (Tw). Furthermore, the noise ratio (SNR) is important effect factor for 2D NMR observation data and inversion accuracy, and the lowest threshold of signal to noise ratio (SNR) is about 150.关键词
二维核磁共振测井/多回波间隔观测模式/扩散系数/横向弛豫时间/含气饱和度/流体模型Key words
two-dimension NMR (2D NMR) logging/ multi-TE activation/ diffuse coefficient (D)/ transverse relaxation time (T2)/ different gas saturation/ fluid model分类
天文与地球科学引用本文复制引用
谭茂金,邹友龙,刘兵开,杨萱..气水模型(T2,D)二维核磁共振测井数值模拟及参数影响分析[J].测井技术,2011,35(2):130-136,7.基金项目
油气资源与探测国家重点实验室开放课题(2009009) （2009009）
中央高校基本科研业务费专项资金(2010ZY28) （2010ZY28）
国家重大专项"大型油气田及煤层气开发"(2011ZX05014-001-001) （2011ZX05014-001-001）
