基于径向谱的位场向下延拓正则参数选取方法  

New regularization parameter selection for potential field downward continuation based on the radial spectrum

作　　者：曾小牛 李夕海[1] 陈鼎新[1,2] 杨晓云[1] 

机构地区：[1]第二炮兵工程大学,陕西西安710025 [2]清华大学自动化系,北京100086

出　　处：《石油地球物理勘探》2015年第4期749-754,7,共6页Oil Geophysical Prospecting

基　　金：国家自然科学基金(41374154)资助

摘　　要：Tikhonov正则算法是解决位场向下延拓不适定性广泛采用的一种有效方法,最优正则参数的选取对下延精度和计算时间都有影响。为了快速、有效地选取正则参数,提出一种基于位场径向平均功率谱的Tikhonov正则参数选取方法。该方法通过建立由径向平均功率谱确定的截止波数和Tikhonov正则低通滤波函数的截止波数的关系来确定正则参数。基于理论重力模型数据及航磁实测数据将新方法同以往普遍采用的L-曲线法、C-范数法进行了正则向下延拓效果的对比实验。实验结果表明,新方法实现简单、物理意义明确,且选取的正则参数优于另外两种经典方法。Downward continuation of potential field data plays an important role in gravity and magnetic data interpretation.Tikhonov regularization method is an effective method for the downward continuation of potential field.The key of this method is regularization parameter selection,which directly affect the precision and the computation time of the downward continuation.In order to effectively choose a regularization parameter,this paper proposes a new selection method based on the radialaverage power spectrum of the potential field.The new method builds the relationship between the two cutoff wavenumbers which are respectively decided by the radial-average power spectrum and the Tikhonov regularization low-pass filter.Tests on theoretical gravity model and real aeromagnetic data shows that the Tikhonov downward continuation precision based on the regularization parameter selection with the proposed method is more accurate than the L-curve and C-norm methods.Moreover,the proposed method is easy to be realized.

关 键 词：向下延拓 Tikhonov正则 径向平均功率谱 L-曲线法 

分 类 号：P631[天文地球—地质矿产勘探]