(1. 中南大學(xué)地球科學(xué)與信息物理學(xué)院，長沙 410083；
2. 中南大學(xué)有色資源與地質(zhì)災(zāi)害探查湖南省重點(diǎn)實驗室，長沙 410083)
摘 要: 由于實測數(shù)據(jù)包含噪聲和其固有的不完備性，決定了頻率域電磁測深數(shù)據(jù)在數(shù)學(xué)計算上是一個非唯一解的、不穩(wěn)定的問題，這就意味著不同的地電模型可以擬合在同一剖面上的視參數(shù)數(shù)據(jù)。面對這種問題可以通過給定加權(quán)的正則化方法使得病態(tài)逆問題變?yōu)榉�(wěn)定。本研究實現(xiàn)了頻率域線源可控源音頻大地電流法(CSAET法)剖面的二維反演計算。為了使反演過程穩(wěn)定，采用了模型參數(shù)的平滑度約束的方法，并使用自適應(yīng)正則化參數(shù)技術(shù)客觀上調(diào)整了反演參數(shù)。并且在計算過程中利用了伴隨方程近似計算方法，減少了計算靈敏度的耗時。數(shù)值計算表明，利用合成的數(shù)據(jù)可以得到精確的反演結(jié)果。
關(guān)鍵字: CSAET法；線源；二維反演；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
