| 摘要: |
| 提出一种重磁异常非线性反演的直接解法，它是基于迭代法求解一个非线性积分方程。当物性界面起伏分布Δh满足|Δh|<(根号2–1)h时，积分的被积函数可展成Δh的幂级数，考虑Δh高次项的影响，应用简单迭代法可将问题化成相应的线性积分方程，并可用B样条函数求解。在不同磁化方向的ΔT和Za异常上和变密度界面引起的重力异常上实现了模拟反演。精度显著高于线性直接解。在南海东沙群岛地区进行了莫霍面的反演计算，效果良好。 |
| 关键词: 重磁异常反演 非线性积分方程 送代 B样条函数 |
| DOI：10.11693/hyhz200003011011 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，49274212号 |
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| NONLINEAR ITERATIVE INVERSION OF GRAVITY AND MAGNETIC INTERFACES TO TWO DIMENSIONAL ANOMALIES BASED ON B SPLINE FUNCTION |
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WANG Shuo-ru1, YU Zeng-hui2
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1.Department of Marine Geoscience, Ocean University of Qingdao, Qingdao266003;2.Institute of Oceanology, The Chinese Academy of Sciences, Qingdao266071
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| Abstract: |
| Inversion of gravity and magnetic interfaces by gravity and magnetic anomalies, which demonstrates the distribution of subterranean materials, is an important realm in geophysics. In this realm, the common methods are based on Parker formula in frequency domain. For these methods there is the problem of choosing the power number of the relief of interfaces Δh, and to magnetic interfaces they are only applicable under the condition of perpendicular magnetization. In order to avoid the errors caused by frequent Fourier transferring in frequency domain and by omitting the higher power items for linear solutions in space domain, in this article a new nonlinear iterative solution in space domain is presented. It solves the integral equation based on simple and flexible B spline. When the relied of interfaces Δh is in |Δh|<(square root 2–1)h, the effect of the higher power items is considered commonly, whereas it is omitted by other methods. Models and examples show that the method is better than Parker’s formula method and the linear solution in space domain. |
| Key words: Inversion of gravity and magnetic interfaces, Nonlinear integral equation, Interactive B spline function |
