(1. 中南大学地球科学与信息物理学院，长沙 410083；
2. 中南大学有色资源与地质灾害探查湖南省重点实验室，长沙 410083)
摘 要: 由于实测数据包含噪声和其固有的不完备性，决定了频率域电磁测深数据在数学计算上是一个非唯一解的、不稳定的问题，这就意味着不同的地电模型可以拟合在同一剖面上的视参数数据。面对这种问题可以通过给定加权的正则化方法使得病态逆问题变为稳定。本研究实现了频率域线源可控源音频大地电流法(CSAET法)剖面的二维反演计算。为了使反演过程稳定，采用了模型参数的平滑度约束的方法，并使用自适应正则化参数技术客观上调整了反演参数。并且在计算过程中利用了伴随方程近似计算方法，减少了计算灵敏度的耗时。数值计算表明，利用合成的数据可以得到精确的反演结果。
关键字: CSAET法；线源；二维反演；平滑限制
（1. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China;
2. Key Laboratory of Non-ferrous Resources and Geological Detection,
Ministry of Hunan province, Changsha 410083, China）
Abstract:The frequency domain electromagnetic sounding calculation is a mathematically non-unique problem with instability because the observed data contain noise and its inherent incompleteness. Thus different models can fit the data from the same cross-section well. This problem can be solved by using regularization method. This study implements the two-dimensional inversion of frequency domain line source CSAET. The method of model parameters smoothness constraints and adaptive regularization technique was used to stabilize the inversion process. Besides, the adoption of adjoin equation approximate calculation method is more time efficient in the calculation of sensitivity. The numerical calculation results show that the use of synthetic data can contribute to the accurate inversion results.
Key words: CSAET method; line current source; 2D inversion; smoothness-constrained
